docs: Note version 0.4.0 release

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

Makefile

@@ -83,7 +83,7 @@ $(OUT)declfunc.lds: src/declfunc.lds.S
 
 $(OUT)klipper.o: $(patsubst %.c, $(OUT)src/%.o,$(src-y)) $(OUT)declfunc.lds
 	@echo "  Linking $@"
-	$(Q)$(CC) $(CFLAGS) -Wl,-r -Wl,-T,$(OUT)declfunc.lds -nostdlib $(patsubst %.c, $(OUT)src/%.o,$(src-y)) -o $@
+	$(Q)$(CC) $(CFLAGS) $(CFLAGS_klipper.o) -Wl,-r -Wl,-T,$(OUT)declfunc.lds -nostdlib $(patsubst %.c, $(OUT)src/%.o,$(src-y)) -o $@
 
 $(OUT)compile_time_request.o: $(OUT)klipper.o ./scripts/buildcommands.py
 	@echo "  Building $@"

config/avrsim.cfg

@@ -1,7 +1,7 @@
 # Support for internal testing with the "simulavr" program.  To use
 # this config, compile the firmware for an AVR atmega644p, disable the
 # AVR watchdog timer, set the MCU frequency to 20000000, and set the
-# serial baud rate to 115200.
+# serial baud rate to 250000.
 
 [stepper_x]
 # Pins: PA5, PA4, PA1
@@ -42,11 +42,11 @@ step_pin: ar19
 dir_pin: ar18
 enable_pin: ar25
 step_distance: .004242
-max_velocity: 200000
-max_accel: 3000
+nozzle_diameter: 0.500
+filament_diameter: 3.500
 heater_pin: ar4
-thermistor_pin: analog1
-thermistor_type: EPCOS 100K B57560G104F
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog1
 control: pid
 pid_Kp: 22.2
 pid_Ki: 1.08
@@ -57,19 +57,17 @@ max_temp: 210
 
 [heater_bed]
 heater_pin: ar3
-thermistor_pin: analog0
-thermistor_type: EPCOS 100K B57560G104F
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog0
 control: watermark
 min_temp: 0
 max_temp: 110
 
 [fan]
 pin: ar14
-hard_pwm: 1
 
 [mcu]
 serial: /tmp/pseudoserial
-baud: 250000
 pin_map: arduino
 
 [printer]

config/example-corexy.cfg

@@ -0,0 +1,84 @@
+# This file serves as documentation for config parameters of corexy
+# style printers. One may copy and edit this file to configure a new
+# corexy printer. Only parameters unique to corexy printers are
+# described here - see the "example.cfg" file for description of
+# common config parameters.
+
+# DO NOT COPY THIS FILE WITHOUT CAREFULLY READING AND UPDATING IT
+# FIRST. Incorrectly configured parameters may cause damage.
+
+# The stepper_x section is used to describe the X axis as well as the
+# stepper controlling the X+Y movement
+[stepper_x]
+step_pin: ar54
+dir_pin: ar55
+enable_pin: !ar38
+step_distance: .01
+endstop_pin: ^ar2
+homing_speed: 50.0
+position_min: 0
+position_endstop: 0
+position_max: 200
+
+# The stepper_y section is used to describe the Y axis as well as the
+# stepper controlling the X-Y movement
+[stepper_y]
+step_pin: ar60
+dir_pin: ar61
+enable_pin: !ar56
+step_distance: .01
+endstop_pin: ^ar15
+homing_speed: 50.0
+position_min: 0
+position_endstop: 0
+position_max: 200
+
+[stepper_z]
+step_pin: ar46
+dir_pin: ar48
+enable_pin: !ar62
+step_distance: .01
+endstop_pin: ^ar19
+position_min: 0.1
+position_endstop: 0.5
+position_max: 200
+
+[extruder]
+step_pin: ar26
+dir_pin: ar28
+enable_pin: !ar24
+step_distance: .0022
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: ar10
+sensor_type: ATC Semitec 104GT-2
+sensor_pin: analog13
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: ar8
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog14
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: ar9
+
+[mcu]
+serial: /dev/ttyACM0
+pin_map: arduino
+
+[printer]
+kinematics: corexy
+#   This option must be "corexy" for corexy printers.
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 25
+max_z_accel: 30

config/example-delta.cfg

@@ -9,8 +9,7 @@
 
 # The stepper_a section describes the stepper controlling the front
 # left tower (at 210 degrees). This section also controls the homing
-# parameters (homing_speed, homing_retract_dist) and maximum tower
-# length (position_max) for all towers.
+# parameters (homing_speed, homing_retract_dist) for all towers.
 [stepper_a]
 step_pin: ar54
 dir_pin: ar55
@@ -19,7 +18,6 @@ step_distance: .01
 endstop_pin: ^ar2
 homing_speed: 50.0
 position_endstop: 297.05
-position_max: 297.55
 
 # The stepper_b section describes the stepper controlling the front
 # right tower (at 330 degrees)
@@ -46,11 +44,11 @@ step_pin: ar26
 dir_pin: ar28
 enable_pin: !ar24
 step_distance: .0022
-max_velocity: 200
-max_accel: 3000
+nozzle_diameter: 0.400
+filament_diameter: 1.750
 heater_pin: ar10
-thermistor_pin: analog13
-thermistor_type: ATC Semitec 104GT-2
+sensor_type: ATC Semitec 104GT-2
+sensor_pin: analog13
 control: pid
 pid_Kp: 22.2
 pid_Ki: 1.08
@@ -60,8 +58,8 @@ max_temp: 250
 
 [heater_bed]
 heater_pin: ar8
-thermistor_pin: analog14
-thermistor_type: EPCOS 100K B57560G104F
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog14
 control: watermark
 min_temp: 0
 max_temp: 130
@@ -69,27 +67,37 @@ max_temp: 130
 # Extruder print fan (omit section if fan not present)
 #[fan]
 #pin: ar9
-#hard_pwm: 1
 
 [mcu]
 serial: /dev/ttyACM0
-baud: 250000
 pin_map: arduino
 
 [printer]
 kinematics: delta
-#   This option must be "delta" for linear delta printers
+#   This option must be "delta" for linear delta printers.
 max_velocity: 300
+#   Maximum velocity (in mm/s) of the toolhead relative to the
+#   print. This limits the velocity of the toolhead relative to the
+#   print - at the extreme end of the print envelope the delta axis
+#   steppers themselves may briefly exceed this speed by up to 3
+#   times. This parameter must be specified.
 max_accel: 3000
+#   Maximum acceleration (in mm/s^2) of the toolhead relative to the
+#   print. This limits the acceleration of the toolhead relative to
+#   the print - at the extreme end of the print envelope the delta
+#   axis steppers may briefly exceed this acceleration by up to 3
+#   times. This parameter must be specified.
 max_z_velocity: 200
 #   For delta printers this limits the maximum velocity (in mm/s) of
 #   moves with z axis movement. This setting can be used to reduce the
 #   maximum speed of up/down moves (which require a higher step rate
-#   than other moves on a delta printer).
+#   than other moves on a delta printer). The default is to use
+#   max_velocity for max_z_velocity.
 delta_arm_length: 333.0
 #   Length (in mm) of the diagonal rods that connect the linear axes
-#   to the print head
+#   to the print head. This parameter must be provided.
 delta_radius: 174.75
 #   Radius (in mm) of the horizontal circle formed by the three linear
 #   axis towers. This parameter may also be calculated as:
 #    delta_radius = smooth_rod_offset - effector_offset - carriage_offset
+#   This parameter must be provided.

config/example.cfg

@@ -1,6 +1,8 @@
 # This file serves as documentation for config parameters. One may
 # copy and edit this file to configure a new cartesian style
-# printer. For delta style printers, see the "example-delta.cfg" file.
+# printer. For delta style printers, see the "example-delta.cfg"
+# file. For corexy/h-bot style printers, see the "example-corexy.cfg"
+# file.
 
 # DO NOT COPY THIS FILE WITHOUT CAREFULLY READING AND UPDATING IT
 # FIRST. Incorrectly configured parameters may cause damage.
@@ -19,27 +21,35 @@
 # the X axis in a cartesian robot
 [stepper_x]
 step_pin: ar29
-#   Step GPIO pin (triggered high)
+#   Step GPIO pin (triggered high). This parameter must be provided.
 dir_pin: !ar28
-#   Direction GPIO pin (high indicates positive direction)
+#   Direction GPIO pin (high indicates positive direction). This
+#   parameter must be provided.
 enable_pin: !ar25
-#   Enable pin (default is enable high; use ! to indicate enable low)
+#   Enable pin (default is enable high; use ! to indicate enable
+#   low). If this parameter is not provided then the stepper motor
+#   driver must always be enabled.
 step_distance: .0225
-#   Distance in mm that each step causes the axis to travel
+#   Distance in mm that each step causes the axis to travel. This
+#   parameter must be provided.
 endstop_pin: ^ar0
-#   Endstop switch detection pin
-homing_speed: 50.0
-#   Maximum velocity (in mm/s) of the stepper when homing
-homing_retract_dist: 5.0
-#   Distance to backoff (in mm) before homing a second time during homing
-homing_positive_dir: False
-#   If true, homes in a positive direction (away from zero)
-homing_stepper_phases: 0
+#   Endstop switch detection pin. This parameter must be provided for
+#   the X, Y, and Z steppers on cartesian style printers.
+#homing_speed: 5.0
+#   Maximum velocity (in mm/s) of the stepper when homing. The default
+#   is 5mm/s.
+#homing_retract_dist: 5.0
+#   Distance to backoff (in mm) before homing a second time during
+#   homing. The default is 5mm.
+#homing_positive_dir: False
+#   If true, homes in a positive direction (away from zero). The
+#   default is False.
+#homing_stepper_phases: 0
 #   One may optionally set this to the number of phases of the stepper
 #   motor driver (which is the number of micro-steps multiplied by
 #   four). When set, the phase of the stepper driver will be used
 #   during homing to improve the accuracy of the endstop switch.
-homing_endstop_accuracy: 0.200
+#homing_endstop_accuracy: 0.200
 #   Sets the expected accuracy (in mm) of the endstop. This represents
 #   the maximum error distance the endstop may trigger (eg, if an
 #   endstop may occasionally trigger 100um early or up to 100um late
@@ -56,12 +66,14 @@ homing_endstop_accuracy: 0.200
 #   phase will be used on all subsequent homes.
 position_min: -0.25
 #   Minimum valid distance (in mm) the user may command the stepper to
-#   move to
+#   move to.  The default is 0mm.
 position_endstop: 0
-#   Location of the endstop (in mm)
+#   Location of the endstop (in mm). This parameter must be provided
+#   for the X, Y, and Z steppers on cartesian style printers.
 position_max: 200
 #   Maximum valid distance (in mm) the user may command the stepper to
-#   move to
+#   move to. This parameter must be provided for the X, Y, and Z
+#   steppers on cartesian style printers.
 
 # The stepper_y section is used to describe the stepper controlling
 # the Y axis in a cartesian robot. It has the same settings as the
@@ -99,84 +111,148 @@ step_pin: ar19
 dir_pin: ar18
 enable_pin: !ar25
 step_distance: .004242
-max_velocity: 200000
+nozzle_diameter: 0.500
+#   Diameter of the nozzle orifice (in mm). This parameter must be
+#   provided.
+filament_diameter: 3.500
+#   Diameter of the raw filament (in mm) as it enters the
+#   extruder. This parameter must be provided.
+#max_extrude_cross_section:
+#   Maximum area of the cross section of an extrusion line (in
+#   mm^2). If a move requests an extrusion rate that would exceed this
+#   value it will cause an error to be returned. The default is: 4.0 *
+#   nozzle_diameter^2
+#max_extrude_only_distance: 50.0
+#   Maximum length (in mm of raw filament) that an extrude only move
+#   may be. If an extrude only move requests a distance greater than
+#   this value it will cause an error to be returned. The default is
+#   50mm.
+#max_extrude_only_velocity:
 #   Maximum velocity (in mm/s) of the extruder motor for extrude only
-#   moves.
-max_accel: 3000
+#   moves. If this is not specified then it is calculated to match the
+#   limit an XY printing move with a max_extrude_cross_section
+#   extrusion would have.
+#max_extrude_only_accel:
 #   Maximum acceleration (in mm/s^2) of the extruder motor for extrude
-#   only moves.
-#
-# The remaining variables describe the extruder heater
-pressure_advance: 0.0
+#   only moves. If this is not specified then it is calculated to
+#   match the limit an XY printing move with a
+#   max_extrude_cross_section extrusion would have.
+#pressure_advance: 0.0
 #   The amount of raw filament to push into the extruder during
 #   extruder acceleration. An equal amount of filament is retracted
 #   during deceleration. It is measured in millimeters per
-#   millimeter/second
+#   millimeter/second. The default is 0, which disables pressure
+#   advance.
+#pressure_advance_lookahead_time: 0.010
+#   A time (in seconds) to "look ahead" at future extrusion moves when
+#   calculating pressure advance. This is used to reduce the
+#   application of pressure advance during cornering moves that would
+#   otherwise cause retraction followed immediately by pressure
+#   buildup. This setting only applies if pressure_advance is
+#   non-zero. The default is 0.010 (10 milliseconds).
+#
+# The remaining variables describe the extruder heater
 heater_pin: ar4
-#   PWM output pin controlling the heater
-thermistor_pin: analog1
-#   Analog input pin connected to thermistor
-thermistor_type: EPCOS 100K B57560G104F
-#   Type of thermistor (see klippy/heater.py for available types)
-pullup_resistor: 4700
-#   The resistance (in ohms) of the pullup attached to the thermistor
+#   PWM output pin controlling the heater. This parameter must be
+#   provided.
+#max_power: 1.0
+#   The maximum power (expressed as a value from 0.0 to 1.0) that the
+#   heater_pin may be set to. The value 1.0 allows the pin to be set
+#   fully enabled for extended periods, while a value of 0.5 would
+#   allow the pin to be enabled for no more than half the time. This
+#   setting may be used to limit the total power output (over extended
+#   periods) to the heater. The default is 1.0.
+sensor_type: EPCOS 100K B57560G104F
+#   Type of sensor - this may be "EPCOS 100K B57560G104F", "ATC
+#   Semitec 104GT-2", or "AD595". This parameter must be provided.
+sensor_pin: analog1
+#   Analog input pin connected to the sensor. This parameter must be
+#   provided.
+#pullup_resistor: 4700
+#   The resistance (in ohms) of the pullup attached to the
+#   thermistor. This parameter is only valid when the sensor is a
+#   thermistor. The default is 4700 ohms.
+#adc_voltage: 5.0
+#   The ADC comparison voltage. This parameter is only valid when the
+#   sensor is an AD595. The default is 5 volts.
 control: pid
-#   Control algorithm (either pid or watermark)
+#   Control algorithm (either pid or watermark). This parameter must
+#   be provided.
 pid_Kp: 22.2
-#   Kp is the "proportional" constant for the pid
+#   Kp is the "proportional" constant for the pid. This parameter must
+#   be provided for PID heaters.
 pid_Ki: 1.08
-#   Ki is the "integral" constant for the pid
+#   Ki is the "integral" constant for the pid. This parameter must be
+#   provided for PID heaters.
 pid_Kd: 114
-#   Kd is the "derivative" constant for the pid
-pid_deriv_time: 2.0
+#   Kd is the "derivative" constant for the pid. This parameter must
+#   be provided for PID heaters.
+#pid_deriv_time: 2.0
 #   A time value (in seconds) over which the derivative in the pid
-#   will be smoothed to reduce the impact of measurement noise
-pid_integral_max: 255
-#   The maximum "windup" the integral term may accumulate
-min_extrude_temp: 170
+#   will be smoothed to reduce the impact of measurement noise. The
+#   default is 2 seconds.
+#pid_integral_max:
+#   The maximum "windup" the integral term may accumulate. The default
+#   is to use the same value as max_power.
+#min_extrude_temp: 170
 #   The minimum temperature (in Celsius) at which extruder move
-#   commands may be issued
+#   commands may be issued. The default is 170 Celsius.
 min_temp: 0
-#   Minimum temperature in Celsius (mcu will shutdown if not met)
+#   Minimum temperature in Celsius (mcu will shutdown if not
+#   met). This parameter must be provided.
 max_temp: 210
 #   Maximum temperature (mcu will shutdown if temperature is above
-#   this value)
+#   this value). This parameter must be provided.
 
 # The heater_bed section describes a heated bed (if present - omit
 # section if not present).
 [heater_bed]
 heater_pin: ar3
-thermistor_pin: analog0
-thermistor_type: EPCOS 100K B57560G104F
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog0
 control: watermark
-max_delta: 2.0
-#   The number of degrees in Celsius above the target temperature
-#   before disabling the heater as well as the number of degrees below
-#   the target before re-enabling the heater.
+#max_delta: 2.0
+#   On 'watermark' controlled heaters this is the number of degrees in
+#   Celsius above the target temperature before disabling the heater
+#   as well as the number of degrees below the target before
+#   re-enabling the heater. The default is 2 degrees Celsius.
 min_temp: 0
 max_temp: 110
 
 # Extruder print fan (omit section if fan not present)
 [fan]
 pin: ar14
-#   PWM output pin controlling the heater
-hard_pwm: 1
+#   PWM output pin controlling the fan. This parameter must be
+#   provided.
+#hard_pwm: 0
 #   Set this value to force hardware PWM instead of software PWM. Set
 #   to 1 to force a hardware PWM at the fastest rate; set to a higher
-#   number (eg, 1024) to force hardware PWM with the given cycle time
-#   in clock ticks.
-kick_start_time: 0.100
+#   number to force hardware PWM with the given cycle time in clock
+#   ticks. The default is 0 which enables software PWM with a cycle
+#   time of 10ms.
+#kick_start_time: 0.100
 #   Time (in seconds) to run the fan at full speed when first enabling
-#   it (helps get the fan spinning)
+#   it (helps get the fan spinning). The default is 0.100 seconds.
 
 # Micro-controller information
 [mcu]
 serial: /dev/ttyACM0
-#   The serial port to connect to the MCU
-baud: 250000
-#   The baud rate to use
+#   The serial port to connect to the MCU. The default is /dev/ttyS0
+#baud: 250000
+#   The baud rate to use. The default is 250000.
 pin_map: arduino
-#   This option may be used to enable Arduino pin name aliases
+#   This option may be used to enable Arduino pin name aliases. The
+#   default is to not enable the aliases.
+#restart_method: arduino
+#   This controls the mechanism the host will use to reset the
+#   micro-controller. The choices are 'arduino', 'rpi_usb', and
+#   'command'. The 'arduino' method (toggle DTR; set baud to 1200) is
+#   common on Arduino boards and clones. The 'rpi_usb' method is
+#   useful on Raspberry Pi boards with micro-controllers powered over
+#   USB - it briefly disables power to all USB ports to accomplish a
+#   micro-controller reset. The 'command' method involves sending a
+#   Klipper command to the micro-controller so that it can reset
+#   itself. The default is 'arduino'.
 custom:
 #   This option may be used to specify a set of custom
 #   micro-controller commands to be sent at the start of the
@@ -187,25 +263,34 @@ custom:
 # The printer section controls high level printer settings
 [printer]
 kinematics: cartesian
-#   This option must be "cartesian" for cartesian printers
+#   This option must be "cartesian" for cartesian printers.
 max_velocity: 500
 #   Maximum velocity (in mm/s) of the toolhead (relative to the
-#   print)
+#   print). This parameter must be specified.
 max_accel: 3000
 #   Maximum acceleration (in mm/s^2) of the toolhead (relative to the
-#   print)
-max_z_velocity: 250
+#   print). This parameter must be specified.
+#max_accel_to_decel:
+#   A pseudo acceleration (in mm/s^2) controlling how fast the
+#   toolhead may go from acceleration to deceleration. It is used to
+#   reduce the top speed of short zig-zag moves (and thus reduce
+#   printer vibration from these moves). The default is half of
+#   max_accel.
+max_z_velocity: 25
 #   For cartesian printers this sets the maximum velocity (in mm/s) of
 #   movement along the z axis. This setting can be used to restrict
-#   the maximum speed of the z stepper motor on cartesian printers.
+#   the maximum speed of the z stepper motor on cartesian
+#   printers. The default is to use max_velocity for max_z_velocity.
 max_z_accel: 30
 #   For cartesian printers this sets the maximum acceleration (in
 #   mm/s^2) of movement along the z axis. It limits the acceleration
-#   of the z stepper motor on cartesian printers.
-motor_off_time: 60
+#   of the z stepper motor on cartesian printers. The default is to
+#   use max_accel for max_z_accel.
+#motor_off_time: 600
 #   Time (in seconds) of idle time before the printer will try to
-#   disable active motors.
-junction_deviation: 0.02
+#   disable active motors. The default is 600 seconds.
+#junction_deviation: 0.02
 #   Distance (in mm) used to control the internal approximated
 #   centripetal velocity cornering algorithm. A larger number will
-#   permit higher "cornering speeds" at the junction of two moves.
+#   permit higher "cornering speeds" at the junction of two moves. The
+#   default is 0.02mm.

config/generic-rambo.cfg

@@ -0,0 +1,90 @@
+# This file contains common pin mappings for RAMBo boards. To use this
+# config, the firmware should be compiled for the AVR atmega2560.
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: PC0
+dir_pin: PL1
+enable_pin: !PA7
+step_distance: .0125
+endstop_pin: ^PB6
+homing_speed: 50
+position_endstop: 0
+position_max: 200
+
+[stepper_y]
+step_pin: PC1
+dir_pin: !PL0
+enable_pin: !PA6
+step_distance: .0125
+endstop_pin: ^PB5
+homing_speed: 50
+position_endstop: 0
+position_max: 200
+
+[stepper_z]
+step_pin: PC2
+dir_pin: PL2
+enable_pin: !PA5
+step_distance: 0.00025
+endstop_pin: ^PB4
+homing_speed: 5
+position_endstop: 0
+position_max: 200
+
+[extruder]
+step_pin: PC3
+dir_pin: PL6
+enable_pin: !PA4
+step_distance: .002
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: PH6
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF0
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: PE5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF2
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: PH5
+
+[mcu]
+serial: /dev/ttyACM0
+custom:
+  # Turn off yellow led
+  set_digital_out pin=PB7 value=0
+  # Stepper micro-step pins
+  set_digital_out pin=PG1 value=1
+  set_digital_out pin=PG0 value=1
+  set_digital_out pin=PK7 value=1
+  set_digital_out pin=PG2 value=1
+  set_digital_out pin=PK6 value=1
+  set_digital_out pin=PK5 value=1
+  set_digital_out pin=PK3 value=1
+  set_digital_out pin=PK4 value=1
+  # Initialize digipot
+  send_spi_message pin=PD7 msg=0487 # X = ~0.75A
+  send_spi_message pin=PD7 msg=0587 # Y = ~0.75A
+  send_spi_message pin=PD7 msg=0387 # Z = ~0.75A
+  send_spi_message pin=PD7 msg=00A5 # E0
+  send_spi_message pin=PD7 msg=017D # E1
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100

config/generic-ramps.cfg

@@ -0,0 +1,74 @@
+# This file contains common pin mappings for RAMPS (v1.3 and later)
+# boards. RAMPS boards typically use a firmware compiled for the AVR
+# atmega2560 (though other AVR chips are also possible).
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: ar54
+dir_pin: ar55
+enable_pin: !ar38
+step_distance: .0125
+endstop_pin: ^ar3
+homing_speed: 50
+position_endstop: 0
+position_max: 200
+
+[stepper_y]
+step_pin: ar60
+dir_pin: !ar61
+enable_pin: !ar56
+step_distance: .0125
+endstop_pin: ^ar14
+homing_speed: 50
+position_endstop: 0
+position_max: 200
+
+[stepper_z]
+step_pin: ar46
+dir_pin: ar48
+enable_pin: !ar62
+step_distance: 0.00025
+endstop_pin: ^ar18
+homing_speed: 5
+position_endstop: 0
+position_max: 200
+
+[extruder]
+step_pin: ar26
+dir_pin: ar28
+enable_pin: !ar24
+step_distance: .002
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: ar10
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog13
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: ar8
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog14
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: ar9
+
+[mcu]
+serial: /dev/ttyACM0
+pin_map: arduino
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100

config/makergear-m2-2012.cfg

@@ -48,12 +48,12 @@ step_pin: PC3
 dir_pin: PL6
 enable_pin: !PA4
 step_distance: .004242
-max_velocity: 200000
-max_accel: 3000
+nozzle_diameter: 0.350
+filament_diameter: 1.750
 pressure_advance: 0.07
 heater_pin: PH6
-thermistor_pin: PF0
-thermistor_type: EPCOS 100K B57560G104F
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF0
 control: pid
 pid_Kp: 7.0
 pid_Ki: 0.1
@@ -63,19 +63,17 @@ max_temp: 210
 
 [heater_bed]
 heater_pin: PE5
-thermistor_pin: PF2
-thermistor_type: EPCOS 100K B57560G104F
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF2
 control: watermark
 min_temp: 0
 max_temp: 100
 
 [fan]
 pin: PH5
-hard_pwm: 1
 
 [mcu]
 serial: /dev/ttyACM0
-baud: 250000
 custom:
   # Nozzle fan
   set_pwm_out pin=PH3 cycle_ticks=1 value=155
@@ -101,6 +99,5 @@ custom:
 kinematics: cartesian
 max_velocity: 500
 max_accel: 3000
-max_z_velocity: 250
+max_z_velocity: 25
 max_z_accel: 30
-motor_off_time: 600

docs/Code_Overview.md

@@ -17,7 +17,7 @@ host architectures. The build arranges for includes of
 src/generic/somefile.h).
 
 The **klippy/** directory contains the C and Python source for the
-host part of the firmware.
+host part of the software.
 
 The **lib/** directory contains external 3rd-party library code that
 is necessary to build some targets.
@@ -54,13 +54,13 @@ functions should never pause, delay, or do any work that lasts more
 than a few micro-seconds. These functions schedule work at specific
 times by scheduling timers.
 
-Timer functions are scheduled by calling sched_timer() (located in
+Timer functions are scheduled by calling sched_add_timer() (located in
 **src/sched.c**). The scheduler code will arrange for the given
 function to be called at the requested clock time. Timer interrupts
 are initially handled in an architecture specific interrupt handler
-(eg, **src/avr/timer.c**), but this just calls sched_timer_kick()
-located in **src/sched.c**. The timer interrupt leads to execution of
-schedule timer functions.  Timer functions always run with interrupts
+(eg, **src/avr/timer.c**) which calls sched_timer_dispatch() located
+in **src/sched.c**. The timer interrupt leads to execution of schedule
+timer functions. Timer functions always run with interrupts
 disabled. The timer functions should always complete within a few
 micro-seconds. At completion of the timer event, the function may
 choose to reschedule itself.
@@ -92,8 +92,8 @@ some functionality in C code.
 Initial execution starts in **klippy/klippy.py**. This reads the
 command-line arguments, opens the printer config file, instantiates
 the main printer objects, and starts the serial connection. The main
-execution of gcode commands is in the process_commands() method in
-**klippy/gcode.py**. This code translates the gcode commands into
+execution of G-code commands is in the process_commands() method in
+**klippy/gcode.py**. This code translates the G-code commands into
 printer object calls, which frequently translate the actions to
 commands to be executed on the micro-controller (as declared via the
 DECL_COMMAND macro in the micro-controller code).
@@ -106,3 +106,106 @@ messages from the micro-controller in the Python code (see
 **klippy/serialhdl.py**). The fourth thread writes debug messages to
 the log (see **klippy/queuelogger.py**) so that the other threads
 never block on log writes.
+
+Code flow of a move command
+===========================
+
+A typical printer movement starts when a "G1" command is sent to the
+Klippy host and it completes when the corresponding step pulses are
+produced on the micro-controller. This section outlines the code flow
+of a typical move command. The [kinematics](Kinematics.md) document
+provides further information on the mechanics of moves.
+
+* Processing for a move command starts in gcode.py. The goal of
+  gcode.py is to translate G-code into internal calls. Changes in
+  origin (eg, G92), changes in relative vs absolute positions (eg,
+  G90), and unit changes (eg, F6000=100mm/s) are handled here. The
+  code path for a move is: `process_data() -> process_commands() ->
+  cmd_G1()`. Ultimately the ToolHead class is invoked to execute the
+  actual request: `cmd_G1() -> ToolHead.move()`
+
+* The ToolHead class (in toolhead.py) handles "look-ahead" and tracks
+  the timing of printing actions. The codepath for a move is:
+  `ToolHead.move() -> MoveQueue.add_move() -> MoveQueue.flush() ->
+  Move.set_junction() -> Move.move()`.
+  * ToolHead.move() creates a Move() object with the parameters of the
+  move (in cartesian space and in units of seconds and millimeters).
+  * MoveQueue.add_move() places the move object on the "look-ahead"
+  queue.
+  * MoveQueue.flush() determines the start and end velocities of each
+  move.
+  * Move.set_junction() implements the "trapezoid generator" on a
+  move. The "trapezoid generator" breaks every move into three parts:
+  a constant acceleration phase, followed by a constant velocity
+  phase, followed by a constant deceleration phase. Every move
+  contains these three phases in this order, but some phases may be of
+  zero duration.
+  * When Move.move() is called, everything about the move is known -
+  its start location, its end location, its acceleration, its
+  start/crusing/end velocity, and distance traveled during
+  acceleration/cruising/deceleration. All the information is stored in
+  the Move() class and is in cartesian space in units of millimeters
+  and seconds. Times are stored relative to the start of the print.
+
+  The move is then handed off to the kinematics classes: `Move.move()
+  -> kin.move()`
+
+* The goal of the kinematics classes is to translate the movement in
+  cartesian space to movement on each stepper. The kinematics classes
+  are in cartesian.py, corexy.py, delta.py, and extruder.py. The
+  kinematic class is given a chance to audit the move
+  (`ToolHead.move() -> kin.check_move()`) before it goes on the
+  look-ahead queue, but once the move arrives in *kin*.move() the
+  kinematic class is required to handle the move as specified. The
+  kinematic classes translate the three parts of each move
+  (acceleration, constant "cruising" velocity, and deceleration) to
+  the associated movement on each stepper. Note that the extruder is
+  handled in its own kinematic class. Since the Move() class specifies
+  the exact movement time and since step pulses are sent to the
+  micro-controller with specific timing, stepper movements produced by
+  the extruder class will be in sync with head movement even though
+  the code is kept separate.
+
+* For efficiency reasons, the stepper pulse times are generated in C
+  code. The code flow is: `kin.move() -> MCU_Stepper.step_const() ->
+  stepcompress_push_const()`, or for delta kinematics:
+  `DeltaKinematics.move() -> MCU_Stepper.step_delta() ->
+  stepcompress_push_delta()`. The MCU_Stepper code just performs unit
+  and axis transformation (seconds to clock ticks and millimeters to
+  step distances), and calls the C code. The C code calculates the
+  stepper step times for each movement and fills an array (struct
+  stepcompress.queue) with the corresponding micro-controller clock
+  counter times (in 64bit integers) for every step. Here the
+  "micro-controller clock counter" value directly corresponds to the
+  micro-controller's hardware counter - it is relative to when the
+  micro-controller was last powered up.
+
+* The next major step is to compress the steps: `stepcompress_flush()
+  -> compress_bisect_add()` (in stepcompress.c). This code generates
+  and encodes a series of micro-controller "queue_step" commands that
+  correspond to the list of stepper step times built in the previous
+  stage. These "queue_step" commands are then queued, prioritized, and
+  sent to the micro-controller (via stepcompress.c:steppersync and
+  serialqueue.c:serialqueue).
+
+* Processing of the queue_step commands on the micro-controller starts
+  in command.c which parses the command and calls
+  `command_queue_step()`. The command_queue_step() code (in stepper.c)
+  just appends the parameters of each queue_step command to a per
+  stepper queue. Under normal operation the queue_step command is
+  parsed and queued at least 100ms before the time of its first
+  step. Finally, the generation of stepper events is done in
+  `stepper_event()`. It's called from the hardware timer interrupt at
+  the scheduled time of the first step. The stepper_event() code
+  generates a step pulse and then reschedules itself to run at the
+  time of the next step pulse for the given queue_step parameters. The
+  parameters for each queue_step command are "interval", "count", and
+  "add". At a high-level, stepper_event() runs the following, 'count'
+  times: `do_step(); next_wake_time = last_wake_time + interval;
+  interval += add;`
+
+The above may seem like a lot of complexity to execute a
+movement. However, the only really interesting parts are in the
+ToolHead and kinematic classes. It's this part of the code which
+specifies the movements and their timings. The remaining parts of the
+processing is mostly just communication and plumbing.

docs/Debugging.md

@@ -1,17 +1,18 @@
-The Klippy host code has some tools to help in debugging the firmware.
+The Klippy host code has some tools to help in debugging.
 
-Translating gcode files to firmware commands
-============================================
+Translating gcode files to micro-controller commands
+====================================================
 
 The Klippy host code can run in a batch mode to produce the low-level
-firmware commands associated with a gcode file. Inspecting these
-low-level firmware commands is useful when trying to understand the
+micro-controller commands associated with a gcode file. Inspecting
+these low-level commands is useful when trying to understand the
 actions of the low-level hardware. It can also be useful to compare
-the difference in firmware commands after a code change.
+the difference in micro-controller commands after a code change.
 
 To run Klippy in this batch mode, there is a one time step necessary
-to generate the firmware "data dictionary". This is done by compiling
-the firmware code to obtain the **out/klipper.dict** file:
+to generate the micro-controller "data dictionary". This is done by
+compiling the micro-controller code to obtain the **out/klipper.dict**
+file:
 
 ```
 make menuconfig
@@ -34,13 +35,13 @@ output. This output can be translated to readable text with:
 ```
 
 The resulting file **test.txt** contains a human readable list of
-firmware commands.
+micro-controller commands.
 
 The batch mode disables certain response / request commands in order
 to function. As a result, there will be some differences between
-actual firmware commands and the above output. The generated data is
-useful for testing and inspection; it is not useful for sending to a
-real micro-controller.
+actual commands and the above output. The generated data is useful for
+testing and inspection; it is not useful for sending to a real
+micro-controller.
 
 Testing with simulavr
 =====================
@@ -74,25 +75,20 @@ cd /patch/to/klipper
 make menuconfig
 ```
 
-and compile the firmware for an AVR atmega644p, disable the AVR
-watchdog timer, and set the MCU frequency to 20000000. Then one can
-compile Klipper (run `make`) and then start the simulation with:
+and compile the micro-controller software for an AVR atmega644p,
+disable the AVR watchdog timer, and set the MCU frequency
+to 20000000. Then one can compile Klipper (run `make`) and then start
+the simulation with:
 
 ```
 PYTHONPATH=/path/to/simulavr/src/python/ ./scripts/avrsim.py -m atmega644 -s 20000000 -b 250000 out/klipper.elf
 ```
 
-It may be necessary to create a python virtual environment to run
-Klippy on the target machine. To do so, run:
-
-```
-virtualenv ~/klippy-env
-~/klippy-env/bin/pip install cffi==1.6.0 pyserial==2.7
-```
-
 Then, with simulavr running in another window, one can run the
 following to read gcode from a file (eg, "test.gcode"), process it
-with Klippy, and send it to Klipper running in simulavr:
+with Klippy, and send it to Klipper running in simulavr (see
+[installation](Installation.md) for the steps necessary to build the
+python virtual environment):
 
 ```
 ~/klippy-env/bin/python ./klippy/klippy.py config/avrsim.cfg -i test.gcode -v
@@ -129,3 +125,26 @@ Klipper source code). To do so, run:
 ```
 ~/klippy-env/bin/python ./klippy/console.py /tmp/pseudoserial 250000
 ```
+
+Generating load graphs
+======================
+
+The Klippy log file (/tmp/klippy.log) stores statistics on bandwidth,
+micro-controller load, and host buffer load. It can be useful to graph
+these statistics after a print.
+
+To generate a graph, a one time step is necessary to install the
+"matplotlib" package:
+
+```
+sudo apt-get update
+sudo apt-get install python-matplotlib
+```
+
+Then graphs can be produced with:
+
+```
+~/klipper/scripts/graphstats.py /tmp/klippy.log loadgraph.png
+```
+
+One can then view the resulting **loadgraph.png** file.

docs/Features.md

@@ -1,5 +1,4 @@
-Klipper is an experimental 3d printer firmware. It has several
-compelling features:
+Klipper has several compelling features:
 
 * High precision stepper movement. Klipper utilizes an application
   processor (such as a low-cost Raspberry Pi) when calculating printer
@@ -7,17 +6,16 @@ compelling features:
   stepper motor, it compresses those events, transmits them to the
   micro-controller, and then the micro-controller executes each event
   at the requested time. Each stepper event is scheduled with a
-  precision of no less than 50 micro-seconds. The software does not
-  use kinematic estimations (such as the Bresenham algorithm) -
-  instead it calculates precise step times based on the physics of
-  acceleration and the physics of the machine kinematics. More precise
-  stepper movement translates to quieter and more stable printer
-  operation.
+  precision of 25 micro-seconds or better. The software does not use
+  kinematic estimations (such as the Bresenham algorithm) - instead it
+  calculates precise step times based on the physics of acceleration
+  and the physics of the machine kinematics. More precise stepper
+  movement translates to quieter and more stable printer operation.
 
 * Best in class performance. Klipper is able to achieve high stepping
   rates on both new and old micro-controllers. Even an old 8bit AVR
-  micro-controller can obtain rates up to 150K steps per second. On
-  more recent ARM micro-controllers, rates over 350K steps per second
+  micro-controller can obtain rates over 175K steps per second. On
+  more recent ARM micro-controllers, rates over 450K steps per second
   are possible. Higher stepper rates enable higher print
   velocities. The stepper event timing remains precise even at high
   speeds which improves overall stability.
@@ -34,16 +32,21 @@ compelling features:
   micro-controller architectures as well.
 
 * Simpler code. Klipper uses a very high level language (Python) for
-  most code. The kinematics algorithms, the gcode parsing, the heating
-  and thermistor algorithms, etc. are all written in Python. This
-  makes it easier to develop new functionality.
+  most code. The kinematics algorithms, the G-code parsing, the
+  heating and thermistor algorithms, etc. are all written in
+  Python. This makes it easier to develop new functionality.
 
-* Advanced features. Klipper implements the "pressure advance"
-  algorithm for extruders. When properly tuned, pressure advance
-  reduces extruder ooze. Klipper also implements a novel "stepper
-  phase endstop" algorithm that can dramatically improve the accuracy
-  of typical endstop switches. When properly tuned it can improve a
-  print's first layer bed adhesion.
+* Advanced features:
+  * Klipper implements the "pressure advance" algorithm for
+    extruders. When properly tuned, pressure advance reduces extruder
+    ooze.
+  * Klipper also implements a novel "stepper phase endstop" algorithm
+    that can dramatically improve the accuracy of typical endstop
+    switches. When properly tuned it can improve a print's first layer
+    bed adhesion.
+  * Support for limiting the top speed of short "zigzag" moves to
+    reduce printer vibration and noise. See the
+    [kinematics](Kinematics.md) document for more information.
 
 To get started with Klipper, read the [installation](Installation.md)
 guide.
@@ -65,12 +68,12 @@ Klipper supports many standard 3d printer features:
   gradually accelerate from standstill to cruising speed and then
   decelerate back to a standstill.
 
-* "Lookahead" support. The incoming stream of G-Code movement commands
-  are queued and analyzed - the acceleration between movements in a
-  similar direction will be optimized to reduce print stalls and
-  improve overall print time.
+* "Look-ahead" support. The incoming stream of G-Code movement
+  commands are queued and analyzed - the acceleration between
+  movements in a similar direction will be optimized to reduce print
+  stalls and improve overall print time.
 
-* Support for both delta printers and cartesian style printers.
+* Support for cartesian, delta, and corexy style printers.
 
 Step Benchmarks
 ===============
@@ -80,6 +83,6 @@ represent total number of steps per second on the micro-controller.
 
 | Micro-controller  | 1 stepper active | 3 steppers active |
 | ----------------- | ---------------- | ----------------- |
-| 20Mhz AVR         | 158.7K           | 103K              |
-| 16Mhz AVR         | 126.9K           | 82K               |
-| Arduino Due (ARM) | 352.9K           | 288K              |
+| 20Mhz AVR         | 177K             | 117K              |
+| 16Mhz AVR         | 140K             | 93K               |
+| Arduino Due (ARM) | 462K             | 406K              |

docs/Firmware_Commands.md

@@ -1,278 +0,0 @@
-This document provides high-level information on common firmware
-commands. It is not an authoritative reference for these commands, nor
-is it an exclusive list of all available firmware commands.
-
-This document may be useful for users needing to configure a set of
-hardware actions that their printer may require at startup (via the
-"custom" field in the printer config file), and it may be useful for
-developers wishing to obtain a high-level feel for available firmware
-commands.
-
-See the [protocol](Protocol.md) document for more information on the
-format of commands and their low-level transmission. The commands here
-are described using their "printf" style syntax - for those unfamiliar
-with that format, just note that where a '%...' sequence is seen it
-should be replaced with an actual integer.
-
-Startup Commands
-================
-
-It may be necessary to take certain one-time actions to configure the
-micro-controller and its peripherals. This section lists common
-commands available for that purpose. Unlike other firmware commands,
-these commands run as soon as they are received by the firmware and
-they do not require any particular setup.
-
-These commands are most useful in the "custom" block of the "mcu"
-section of the printer configuration file. This feature is typically
-used to configure the initial settings of LEDs, to configure
-micro-stepping pins, to configure a digipot, etc.
-
-Several of these commands will take a "pin=%u" parameter. The
-low-level firmware uses integer encodings of the hardware pin numbers,
-but to make things more readable the host will translate human
-readable pin names (eg, "PA3") to their equivalent integer
-encodings. By convention, any parameter named "pin" or that has a
-"_pin" suffix will use pin name translation by the host.
-
-Common startup commands:
-
-* set_digital_out pin=%u value=%c : This command immediately
-  configures the given pin as a digital out GPIO and it sets it to
-  either a low level (value=0) or a high level (value=1). This command
-  may be useful for configuring the initial value of LEDs and for
-  configuring the initial value of stepper driver micro-stepping pins.
-
-* set_pwm_out pin=%u cycle_ticks=%u value=%c : This command will
-  immediately configure the given pin to use hardware based
-  pulse-width-modulation (PWM) with the given number of
-  cycle_ticks. The "cycle_ticks" is the number of MCU clock ticks each
-  power on and power off cycle should last. A cycle_ticks value of 1
-  can be used to request the fastest possible cycle time. The "value"
-  parameter is between 0 and 255 with 0 indicating a full off state
-  and 255 indicating a full on state. This command may be useful for
-  enabling CPU and nozzle cooling fans.
-
-* send_spi_message pin=%u msg=%*s : This command can be used to
-  transmit messages to a serial-peripheral-interface (SPI) component
-  connected to the micro-controller. It has been used to configure the
-  startup settings of AD5206 digipots. The 'pin' parameter specifies
-  the chip select line to use during the transmission. The 'msg'
-  indicates the binary message to transmit to the given chip.
-
-Firmware configuration
-======================
-
-Most commands in the firmware require an initial setup before they can
-be successfully invoked. This section provides a high-level overview
-of the micro-controller configuration process. This section and the
-following sections are likely only of interest to developers
-interested in the internal details of Klipper.
-
-When the host first connects to the firmware it always starts by
-obtaining the firmware's data dictionary (see [protocol](Protocol.md)
-for more information). After the data dictionary is obtained the host
-will check if the firmware is in a "configured" state and configure it
-if not. Configuration involves the following phases:
-
-* get_config : The host starts by checking if the firmware is already
-  configured. The firmware responds to this command with a "config"
-  response message. At micro-controller power-on the firmware always
-  starts in an unconfigured state. It remains in this state until the
-  host completes the configuration processes (by issuing a
-  finalize_config command). If the firmware is already configured (and
-  is configured with the desired settings) from a previous
-  host/firmware session then no further action is needed by the host
-  and the configuration process ends successfully.
-
-* allocate_oids count=%c : This command is issued to inform the
-  firmware the maximum number of object-ids (oid) that the host
-  requires. It is only valid to issue this command once. An oid is an
-  integer identifier allocated to each stepper, each endstop, and each
-  schedulable gpio pin. The host determines in advance the number of
-  oids it will require to operate the hardware and passes this to the
-  firmware so that the firmware may allocate sufficient memory to
-  store a mapping from oid to internal firmware object.
-
-* config_XXX oid=%c ... : By convention any command starting with the
-  "config_" prefix creates a new firmware object and assigns the given
-  oid to it. For example, the config_digital_out command will
-  configure the specified pin as a digital output GPIO and create an
-  internal object that the host can use to schedule changes to the
-  given GPIO. The oid parameter passed into the config command is
-  selected by the host and must be between zero and the maximum count
-  supplied in the allocate_oids command. The config commands may only
-  be run when the firmware is not in a configured state (ie, prior to
-  the host sending finalize_config) and after the allocate_oids
-  command has been sent.
-
-* finalize_config crc=%u : The finalize_config command transitions the
-  firmware from an unconfigured state to a configured state. The crc
-  parameter passed to the firmware is stored in the firmware and
-  provided back to the host in "config" response messages. By
-  convention, the host takes a 32bit CRC of the firmware configuration
-  it will request and at the start of subsequent host/firmware
-  communication sessions it checks that the CRC stored in the firmware
-  exactly matches its desired CRC. If the CRC does not match then the
-  host knows the firmware has not been configured in the state desired
-  by the host.
-
-Common firmware objects
------------------------
-
-This section lists some commonly used config commands.
-
-* config_digital_out oid=%c pin=%u default_value=%c max_duration=%u :
-  This command creates an internal firmware object for the given GPIO
-  'pin'. The pin will be configured in digital output mode and set to
-  an initial value as specified by 'default_value' (0 for low, 1 for
-  high). Creating a digital_out object allows the host to schedule
-  GPIO updates for the given pin at specified times (see the
-  schedule_digital_out command described below). Should the firmware
-  go into shutdown mode then all configured digital_out objects will
-  be set back to their default values. The 'max_duration' parameter is
-  used to implement a safety check - if it is non-zero then it is the
-  maximum number of clock ticks that the host may set the given GPIO
-  to a non-default value without further updates. For example, if the
-  default_value is zero and the max_duration is 16000 then if the host
-  sets the gpio to a value of one then it must schedule another update
-  to the gpio pin (to either zero or one) within 16000 clock
-  ticks. This safety feature can be used with heater pins to ensure
-  the host does not set the heater to a value of one and then go
-  off-line.
-
-* config_pwm_out oid=%c pin=%u cycle_ticks=%u default_value=%c
-  max_duration=%u : This command creates an internal object for
-  hardware based PWM pins that the host may schedule updates for. Its
-  usage is analogous to config_digital_out - see the description of
-  the 'set_pwm_out' and 'config_digital_out' commands for parameter
-  description.
-
-* config_soft_pwm_out oid=%c pin=%u cycle_ticks=%u default_value=%c
-  max_duration=%u : This command creates an internal firmware object
-  for software implemented PWM. Unlike hardware pwm pins, a software
-  pwm object does not require any special hardware support (other than
-  the ability to configure the pin as a digital output GPIO). Because
-  the output switching is implemented in the software of the firmware,
-  it is recommended that the cycle_ticks parameter correspond to a
-  time of 10ms or greater. See the description of the 'set_pwm_out'
-  and 'config_digital_out' commands for parameter description.
-
-* config_analog_in oid=%c pin=%u : This command is used to configure a
-  pin in analog input sampling mode. Once configured, the pin can be
-  sampled at regular interval using the query_analog_in command (see
-  below).
-
-* config_stepper oid=%c step_pin=%c dir_pin=%c min_stop_interval=%u
-  invert_step=%c : This command creates an internal stepper
-  object. The 'step_pin' and 'dir_pin' parameters specify the step and
-  direction pins respectively; this command will configure them in
-  digital output mode. The 'invert_step' parameter specifies whether a
-  step occurs on a rising edge (invert_step=0) or falling edge
-  (invert_step=1). The 'min_stop_interval' implements a safety
-  feature - it is checked when the firmware finishes all moves for a
-  stepper - if it is non-zero it specifies the minimum number of clock
-  ticks since the last step. It is used as a check on the maximum
-  stepper velocity that a stepper may have before stopping.
-
-* config_end_stop oid=%c pin=%c pull_up=%c stepper_oid=%c : This
-  command creates an internal "endstop" object. It is used to specify
-  the endstop pins and to enable "homing" operations (see the
-  end_stop_home command below). The command will configure the
-  specified pin in digital input mode. The 'pull_up' parameter
-  determines whether hardware provided pullup resistors for the pin
-  (if available) will be enabled. The 'stepper_oid' parameter
-  specifies the oid of an associated stepper for the given endstop -
-  it is used during homing operations.
-
-Common commands
-===============
-
-This section lists some commonly used run-time commands. It is likely
-only of interest to developers looking to gain insight into Klippy.
-
-* schedule_digital_out oid=%c clock=%u value=%c : This command will
-  schedule a change to a digital output GPIO pin at the given clock
-  time. To use this command a 'config_digital_out' command with the
-  same 'oid' parameter must have been issued during firmware
-  configuration.
-
-* schedule_pwm_out oid=%c clock=%u value=%c : Schedules a change to a
-  hardware PWM output pin. See the 'schedule_digital_out' and
-  'config_pwm_out' commands for more info.
-
-* schedule_soft_pwm_out oid=%c clock=%u value=%c : Schedules a change
-  to a software PWM output pin. See the 'schedule_digital_out' and
-  'config_soft_pwm_out' commands for more info.
-
-* query_analog_in oid=%c clock=%u sample_ticks=%u sample_count=%c
-  rest_ticks=%u min_value=%hu max_value=%hu : This command sets up a
-  recurring schedule of analog input samples. To use this command a
-  'config_analog_in' command with the same 'oid' parameter must have
-  been issued during firmware configuration. The samples will start as
-  of 'clock' time, it will report on the obtained value every
-  'rest_ticks' clock ticks, it will over-sample 'sample_count' number
-  of times, and it will pause 'sample_ticks' number of clock ticks
-  between over-sample samples. The 'min_value' and 'max_value'
-  parameters implement a safety feature - the firmware will verify the
-  sampled value (after any oversampling) is always between the
-  supplied range. This is intended for use with pins attached to
-  thermistors controlling heaters - it can be used to check that a
-  heater is within a temperature range.
-
-* get_status : This command causes the firmware to generate a "status"
-  response message. The host sends this command once a second to
-  obtain the value of the micro-controller clock and to estimate the
-  drift between host and micro-controller clocks. It enables the host
-  to accurately estimate the micro-controller clock.
-
-Stepper commands
-----------------
-
-* queue_step oid=%c interval=%u count=%hu add=%hi : This command
-  schedules 'count' number of steps for the given stepper, with
-  'interval' number of clock ticks between each step. The first step
-  will be 'interval' number of clock ticks since the last scheduled
-  step for the given stepper. If 'add' is non-zero then the interval
-  will be adjusted by 'add' amount after each step. This command
-  appends the given interval/count/add sequence to a per-stepper
-  queue. There may be hundreds of these sequences queued during normal
-  operation. New sequence are appended to the end of the queue and as
-  each sequence completes its 'count' number of steps it is popped
-  from the front of the queue. This system allows the firmware to
-  queue potentially hundreds of thousands of steps - all with reliable
-  and predictable schedule times.
-
-* set_next_step_dir oid=%c dir=%c : This command specifies the value
-  of the dir_pin that the next queue_step command will use.
-
-* reset_step_clock oid=%c clock=%u : Normally, step timing is relative
-  to the last step for a given stepper. This command resets the clock
-  so that the next step is relative to the supplied 'clock' time. The
-  host usually only sends this command at the start of a print.
-
-* end_stop_home oid=%c clock=%u rest_ticks=%u pin_value=%c : This
-  command is used during stepper "homing" operations. To use this
-  command a 'config_end_stop' command with the same 'oid' parameter
-  must have been issued during firmware configuration. When invoked,
-  the firmware will sample the endstop pin every 'rest_ticks' clock
-  ticks and check if it has a value equal to 'pin_value'. If the value
-  matches then the movement queue for the associated stepper will be
-  cleared and the stepper will come to an immediate halt. The host
-  uses this command to implement homing - the host instructs the
-  endstop to sample for the endstop trigger and then it issues a
-  series of queue_step commands to the stepper to move it towards the
-  endstop. Once the stepper hits the endstop, the trigger will be
-  detected, the movement halted, and the host notified.
-
-### Move queue
-
-Each queue_step command utilizes an entry in the firmware "move
-queue". The firmware allocates this queue when it receives the
-"finalize_config" command, and it reports the number of available
-queue entries in "config" response messages.
-
-It is the responsibility of the host to ensure that there is available
-space in the queue before sending a queue_step command. The host does
-this by calculating when each queue_step command completes and
-scheduling new queue_step commands accordingly.

docs/Installation.md

@@ -1,12 +1,15 @@
-Klipper is currently in an experimental state. These instructions
-assume the software will run on a Raspberry Pi computer in conjunction
-with OctoPrint. Klipper supports Atmel ATmega based micro-controllers
-and Arduino Due (Atmel SAM3x8e ARM micro-controllers) printers.
+These instructions assume the software will run on a Raspberry Pi
+computer in conjunction with OctoPrint. It is recommended that a
+Raspberry Pi 2 or Raspberry Pi 3 computer be used as the host
+machine.
 
-It is recommended that a Raspberry Pi 2 or Raspberry Pi 3 computer be
-used as the host. The software will run on a first generation
-Raspberry Pi, but the combined load of OctoPrint, Klipper, and a web
-cam (if applicable) can overwhelm its CPU leading to print stalls.
+It should be possible to run the Klipper host software on any computer
+running a recent Linux distribution, but doing so will require Linux
+admin knowledge to translate these installation instructions to the
+particulars of that machine.
+
+Klipper currently supports Atmel ATmega based micro-controllers and
+Arduino Due (Atmel SAM3x8e ARM micro-controller) printers.
 
 Prepping an OS image
 ====================
@@ -16,40 +19,29 @@ Raspberry Pi computer. Use OctoPi v0.13.0 or later - see the
 [octopi releases](https://github.com/guysoft/OctoPi/releases) for
 release information. One should verify that OctoPi boots and that the
 OctoPrint web server works. After connecting to the OctoPrint web
-page, follow the prompt to upgrade OctoPrint to v1.3.0 or later.
+page, follow the prompt to upgrade OctoPrint to v1.3.2 or later.
 
 After installing OctoPi and upgrading OctoPrint, ssh into the target
 machine (ssh pi@octopi -- password is "raspberry") and run the
 following commands:
 
-```
-sudo apt-get update
-sudo apt-get install libncurses-dev
-sudo apt-get install avrdude gcc-avr binutils-avr avr-libc # AVR toolchain
-sudo apt-get install bossa-cli libnewlib-arm-none-eabi # ARM toolchain
-```
-
-The host software (Klippy) requires a one-time setup - run as the
-regular "pi" user:
-
-```
-virtualenv ~/klippy-env
-~/klippy-env/bin/pip install cffi==1.6.0 pyserial==3.2.1 greenlet==0.4.10
-```
-
-Building Klipper
-================
-
-To obtain Klipper, run the following command on the target machine:
-
 ```
 git clone https://github.com/KevinOConnor/klipper
-cd klipper/
+./klipper/scripts/install-octopi.sh
 ```
 
+The above will download Klipper, install some system dependencies,
+setup Klipper to run at system startup, and start the Klipper host
+software. It will require an internet connection and it may take a few
+minutes to complete.
+
+Building and flashing the micro-controller
+==========================================
+
 To compile the micro-controller code, start by configuring it:
 
 ```
+cd ~/klipper/
 make menuconfig
 ```
 
@@ -60,54 +52,39 @@ configured, run:
 make
 ```
 
-Ignore any warnings you may see about "misspelled signal handler" (it
-is due to a bug fixed in gcc v4.8.3).
-
-Installing Klipper on an AVR micro-controller
----------------------------------------------
-
-The avrdude package can be used to install the micro-controller code
-on an AVR ATmega chip. The exact syntax of the avrdude command is
-different for each micro-controller. The following is an example
-command for atmega2560 chips:
+Finally, for common micro-controllers, the code can be flashed with:
 
 ```
-example-only$ avrdude -C/etc/avrdude.conf -v -patmega2560 -cwiring -P/dev/ttyACM0 -b115200 -D -Uflash:w:/home/pi/klipper/out/klipper.elf.hex:i
+sudo service klipper stop
+make flash FLASH_DEVICE=/dev/ttyACM0
+sudo service klipper start
 ```
 
-Installing Klipper on an Arduino Due
-------------------------------------
+Configuring Klipper
+===================
 
-Klipper currently uses the Arduino Due USB programming port (it will
-not work when connected to the application USB port). The programming
-port is the USB port closest to the power supply. To flash Klipper to
-the Due connect it to the host machine and run:
-
-```
-stty -F /dev/ttyACM0 1200
-bossac -i -p ttyACM0 -R -e -w -v -b ~/klipper/out/klipper.bin
-```
-
-Setting up the printer configuration
-====================================
-
-It is necessary to configure the printer. This is done by modifying a
-configuration file that resides on the host. Start by copying an
-example configuration and editing it.  For example:
+The Klipper configuration is stored in a text file on the Raspberry
+Pi. Take a look at the example config files in the
+[config directory](../config/). The
+[example.cfg](../config/example.cfg) file contains documentation on
+command parameters and it can also be used as an initial config file
+template. However, for most printers, one of the other config files
+may be a more concise starting point. The next step is to copy and
+edit one of these config files - for example:
 
 ```
 cp ~/klipper/config/example.cfg ~/printer.cfg
-nano printer.cfg
+nano ~/printer.cfg
 ```
 
-Make sure to look at and update each setting that is appropriate for
+Make sure to review and update each setting that is appropriate for
 the hardware.
 
-Configuring OctoPrint to use Klippy
-===================================
+Configuring OctoPrint to use Klipper
+====================================
 
 The OctoPrint web server needs to be configured to communicate with
-the Klippy host software. Using a web-browser, login to the OctoPrint
+the Klipper host software. Using a web browser, login to the OctoPrint
 web page, and navigate to the Settings tab. Then configure the
 following items:
 
@@ -115,40 +92,30 @@ Under "Serial Connection" in "Additional serial ports" add
 "/tmp/printer". Then click "Save".
 
 Enter the Settings tab again and under "Serial Connection" change the
-"Serial Port" setting to "/tmp/printer". Change the Baudrate field to
-250000 (this buad rate field is not related to the firmware baudrate
-and may be safely left at 250000). Unselect the "Not only cancel
-ongoing prints but also disconnect..." checkbox.
+"Serial Port" setting to "/tmp/printer". Unselect the "Not only cancel
+ongoing prints but also disconnect..." checkbox. Click "Save".
 
-Under the "Features" tab, unselect "Enable SD support". Then click
-"Save".
-
-Running the host software
-=========================
-
-The host software is executed by running the following as the regular
-"pi" user:
-
-```
-~/klippy-env/bin/python ~/klipper/klippy/klippy.py ~/printer.cfg -l /tmp/klippy.log < /dev/null > /dev/null 2>&1 &
-```
-
-Once Klippy is running, use a web-browser and navigate to the
-OctoPrint web site. Under the "Connection" tab (on the left of the
-main page) make sure the "Serial Port" is set to "/tmp/printer" and
+From the main page, under the "Connection" section (at the top left of
+the page) make sure the "Serial Port" is set to "/tmp/printer" and
 click "Connect". (If "/tmp/printer" is not an available selection then
 try reloading the page.)
 
 Once connected, navigate to the "Terminal" tab and type "status"
-(without the quotes) into the command entry box and click "Send". If
-the Klippy config file was successfully read, and the micro-controller
-was successfully found and configured, then this command will report
-that the printer is ready. Klippy reports error messages via this
-terminal tab. The "status" command can be used to re-report error
-messages.
+(without the quotes) into the command entry box and click "Send". The
+terminal window will likely report there is an error opening the
+config file - issue a "restart" command in the OctoPrint terminal to
+load the config. A "status" command will report the printer is ready
+if the Klipper config file is successfully read and the
+micro-controller is successfully found and configured. It is not
+unusual to have configuration errors during the initial setup - update
+the printer config file and issue "restart" until "status" reports the
+printer is ready.
 
-In addition to common g-code commands, Klippy supports a few extended
-commands - "status" is an example of one of these commands. Use the
-"help" command to get a list of other extended commands. In
-particular, note the "restart" command - use this command to reload
-the Klippy config file after any changes.
+Klipper reports error messages via the OctoPrint terminal tab. The
+"status" command can be used to re-report error messages. The default
+Klipper startup script also places a log in **/tmp/klippy.log** which
+provides more detailed information.
+
+In addition to common g-code commands, Klipper supports a few extended
+commands - "status" and "restart" are examples of these commands. Use
+the "help" command to get a list of other extended commands.

docs/Kinematics.md

@@ -0,0 +1,293 @@
+This document provides an overview of how Klipper implements robot
+motion (its [kinematics](https://en.wikipedia.org/wiki/Kinematics)).
+The contents may be of interest to both developers interested in
+working on the Klipper software as well as users interested in better
+understanding the mechanics of their machines.
+
+Acceleration
+============
+
+Klipper implements a constant acceleration scheme whenever the print
+head changes velocity - the velocity is gradually changed to the new
+speed instead of suddenly jerking to it. Klipper always enforces
+acceleration between the tool head and the print. The filament leaving
+the extruder can be quite fragile - rapid jerks and/or extruder flow
+changes lead to poor quality and poor bed adhesion. Even when not
+extruding, if the print head is at the same level as the print then
+rapid jerking of the head can cause disruption of recently deposited
+filament. Limiting speed changes of the print head (relative to the
+print) reduces risks of disrupting the print.
+
+It is also important to enforce a maximum acceleration of the stepper
+motors to ensure they do not skip or put excessive stress on the
+machine. Klipper limits the acceleration of each stepper by virtue of
+limiting the acceleration of the print head. Enforcing acceleration at
+the print head naturally also enforces acceleration at the steppers
+that control that print head (the inverse is not always true).
+
+Klipper implements constant acceleration. The key formula for constant
+acceleration is:
+```
+velocity(time) = start_velocity + accel*time
+```
+
+Trapezoid generator
+===================
+
+Klipper uses a traditional "trapezoid generator" to model the motion
+of each move - each move has a start speed, it accelerates to a
+cruising speed at constant acceleration, it cruises at a constant
+speed, and then decelerates to the end speed using constant
+acceleration.
+
+![trapezoid](img/trapezoid.svg.png)
+
+It's called a "trapezoid generator" because a velocity diagram of the
+move looks like a trapezoid.
+
+The cruising speed is always greater than or equal to both the start
+speed and the end speed. The acceleration phase may be of zero
+duration (if the start speed is equal to the cruising speed), the
+cruising phase may be of zero duration (if the move immediately starts
+decelerating after acceleration), and/or the deceleration phase may be
+of zero duration (if the end speed is equal to the cruising speed).
+
+![trapezoids](img/trapezoids.svg.png)
+
+Look-ahead
+==========
+
+The "look-ahead" system is used to determine cornering speeds between
+moves.
+
+Consider the following two moves contained on an XY plane:
+
+![corner](img/corner.svg.png)
+
+In the above situation it is possible to fully decelerate after the
+first move and then fully accelerate at the start of the next move,
+but that is not ideal as all that acceleration and deceleration would
+greatly increase the print time and the frequent changes in extruder
+flow would result in poor print quality.
+
+To solve this, the "look-ahead" mechanism queues multiple incoming
+moves and analyzes the angles between moves to determine a reasonable
+speed that can be obtained during the "junction" between two moves. If
+the next move is nearly in the same direction then the head need only
+slow down a little (if at all).
+
+![lookahead](img/lookahead.svg.png)
+
+However, if the next move forms an acute angle (the head is going to
+travel in nearly a reverse direction on the next move) then only a
+small junction speed is permitted.
+
+![lookahead](img/lookahead-slow.svg.png)
+
+The junction speeds are determined using "approximated centripetal
+acceleration". Best
+[described by the author](https://onehossshay.wordpress.com/2011/09/24/improving_grbl_cornering_algorithm/).
+
+Klipper implements look-ahead between moves contained in the XY plane
+that have similar extruder flow rates. Other moves are relatively rare
+and implementing look-ahead between them is unnecessary.
+
+Key formula for look-ahead:
+```
+end_velocity^2 = start_velocity^2 + 2*accel*move_distance
+```
+
+Smoothed look-ahead
+-------------------
+
+Klipper also implements a mechanism for smoothing out the motions of
+short "zigzag" moves. Consider the following moves:
+
+![zigzag](img/zigzag.svg.png)
+
+In the above, the frequent changes from acceleration to deceleration
+can cause the machine to vibrate which causes stress on the machine
+and increases the noise. To reduce this, Klipper tracks both regular
+move acceleration as well as a virtual "acceleration to deceleration"
+rate. Using this system, the top speed of these short "zigzag" moves
+are limited to smooth out the printer motion:
+
+![smoothed](img/smoothed.svg.png)
+
+Specifically, the code calculates what the velocity of each move would
+be if it were limited to this virtual "acceleration to deceleration"
+rate (half the normal acceleration rate by default). In the above
+picture the dashed gray lines represent this virtual acceleration rate
+for the first move. If a move can not reach its full cruising speed
+using this virtual acceleration rate then its top speed is reduced to
+the maximum speed it could obtain at this virtual acceleration
+rate. For most moves the limit will be at or above the move's existing
+limits and no change in behavior is induced. For short zigzag moves,
+however, this limit reduces the top speed. Note that it does not
+change the actual acceleration within the move - the move continues to
+use the normal acceleration scheme up to its adjusted top-speed.
+
+Generating steps
+================
+
+Once the look-ahead process completes, the print head movement for the
+given move is fully known (time, start position, end position,
+velocity at each point) and it is possible to generate the step times
+for the move. This process is done within "kinematic classes" in the
+Klipper code. Outside of these kinematic classes, everything is
+tracked in millimeters, seconds, and in cartesian coordinate space.
+It's the task of the kinematic classes to convert from this generic
+coordinate system to the hardware specifics of the particular printer.
+
+In general, the code determines each step time by first calculating
+where along the line of movement the head would be if a step is
+taken. It then calculates what time the head should be at that
+position. Determining the time along the line of movement can be done
+using the formulas for constant acceleration and constant velocity:
+
+```
+time = sqrt(2*distance/accel + (start_velocity/accel)^2) - start_velocity/accel
+time = distance/cruise_velocity
+```
+
+Cartesian Robots
+----------------
+
+Generating steps for cartesian printers is the simplest case. The
+movement on each axis is directly related to the movement in cartesian
+space.
+
+Delta Robots
+------------
+
+To generate step times on Delta printers it is necessary to correlate
+the movement in cartesian space with the movement on each stepper
+tower.
+
+To simplify the math, for each stepper tower, the code calculates the
+location of a "virtual tower" that is along the line of movement.
+This virtual tower is chosen at the point where the line of movement
+(extended infinitely in both directions) would be closest to the
+actual tower.
+
+![delta-tower](img/delta-tower.svg.png)
+
+It is then possible to calculate where the head will be along the line
+of movement after each step is taken on the virtual tower.
+
+![virtual-tower](img/virtual-tower.svg.png)
+
+The key formula is Pythagoras's theorem:
+```
+distance_to_tower^2 = arm_length^2 - tower_height^2
+```
+
+One complexity is that if the print head passes the virtual tower
+location then the stepper direction must be reversed. In this case
+forward steps will be taken at the start of the move and reverse steps
+will be taken at the end of the move.
+
+### Delta movements beyond simple XY plane ###
+
+Movement calculation is more complicated if a single move contains
+both XY movement and Z movement. These moves are rare, but they must
+still be handled correctly. A virtual tower along the line of movement
+is still calculated, but in this case the tower is not at a 90 degree
+angle relative to the line of movement:
+
+![xy+z-tower](img/xy+z-tower.svg.png)
+
+The code continues to calculate step times using the same general
+scheme as delta moves within an XY plane, but the slope of the tower
+must also be used in the calculations.
+
+Should the move contain only Z movement (ie, no XY movement at all)
+then the same math is used - just in this case the tower is parallel
+to the line of movement.
+
+### Stepper motor acceleration limits ###
+
+With delta kinematics it is possible for a move that is accelerating
+in cartesian space to require an acceleration on a particular stepper
+motor greater than the move's acceleration. This can occur when a
+stepper arm is more horizontal than vertical and the line of movement
+is near that stepper's tower.
+
+Klipper does enforce a maximum ceiling on stepper acceleration that is
+three times the maximum acceleration of a move in cartesian
+space. (Similarly, the maximum velocity of the stepper is limited to
+three times the maximum move velocity.) In order to enforce this
+limit, moves at the extreme edge of the build envelope (where a
+stepper arm may be nearly horizontal) will have a lower maximum
+acceleration and velocity.
+
+Extruder kinematics
+-------------------
+
+Klipper implements extruder motion in its own kinematic class. Since
+the timing and speed of each print head movement is fully known for
+each move, it's possible to calculate the step times for the extruder
+independently from the step time calculations of the print head
+movement.
+
+Basic extruder movement is simple to calculate. The step time
+generation uses the same constant acceleration and constant velocity
+formulas that cartesian robots use.
+
+### Pressure advance ###
+
+Experimentation has shown that it's possible to improve the modeling
+of the extruder beyond the basic extruder formula. In the ideal case,
+as an extrusion move progresses, the same volume of filament should be
+deposited at each point along the move and there should be no volume
+extruded after the move. Unfortunately, it's common to find that the
+basic extrusion formulas cause too little filament to exit the
+extruder at the start of extrusion moves and for excess filament to
+extrude after extrusion ends. This is often referred to as "ooze".
+
+![ooze](img/ooze.svg.png)
+
+The "pressure advance" system attempts to account for this by using a
+different model for the extruder. Instead of naively believing that
+each mm^3 of filament fed into the extruder will result in that amount
+of mm^3 immediately exiting the extruder, it uses a model based on
+pressure. Pressure increases when filament is pushed into the extruder
+(as in [Hooke's law](https://en.wikipedia.org/wiki/Hooke%27s_law)) and
+the pressure necessary to extrude is dominated by the flow rate
+through the nozzle orifice (as in
+[Poiseuille's law](https://en.wikipedia.org/wiki/Poiseuille_law)). The
+key idea is that the relationship between filament, pressure, and flow
+rate can be modeled using a linear coefficient:
+```
+extra_filament = pressure_advance_coefficient * extruder_velocity
+```
+
+See the [pressure advance](Pressure_Advance.md) document for
+information on how to find this pressure advance coefficient.
+
+Once configured, Klipper will push in an additional amount of filament
+during acceleration. The higher the desired filament flow rate, the
+more filament must be pushed in during acceleration to account for
+pressure. During head deceleration the extra filament is retracted
+(the extruder will have a negative velocity).
+
+![pressure-advance](img/pressure-advance.svg.png)
+
+One may notice that the pressure advance algorithm can cause the
+extruder motor to make sudden velocity changes. This is tolerated
+based on the idea that the majority of the inertia in the system is in
+changing the extruder pressure. As long as the extruder pressure does
+not change rapidly the sudden changes in extruder motor velocity are
+tolerated.
+
+One area where sudden velocity changes become problematic is during
+small changes in head speed due to cornering.
+
+![pressure-cornering](img/pressure-cornering.svg.png)
+
+To prevent this, the Klipper pressure advance code utilizes the move
+look-ahead queue to detect intermittent speed changes. During a
+deceleration event the code finds the maximum upcoming head speed
+within a configurable time window. The pressure is then only adjusted
+to this found maximum. This can greatly reduce (or even completely
+eliminate) pressure changes during cornering.

docs/MCU_Commands.md

@@ -0,0 +1,294 @@
+This document provides information on the low-level micro-controller
+commands that are sent from the Klipper "host" software and processed
+by the Klipper micro-controller software. This document is not an
+authoritative reference for these commands, nor is it an exclusive
+list of all available commands.
+
+This document may be useful for users needing to configure a set of
+hardware actions that their printer may require at startup (via the
+"custom" field in the printer config file), and it may be useful for
+developers wishing to obtain a high-level feel for low-level commands.
+
+See the [protocol](Protocol.md) document for more information on the
+format of commands and their transmission. The commands here are
+described using their "printf" style syntax - for those unfamiliar
+with that format, just note that where a '%...' sequence is seen it
+should be replaced with an actual integer. For example, a description
+with "count=%c" could be replaced with the text "count=10".
+
+Startup Commands
+================
+
+It may be necessary to take certain one-time actions to configure the
+micro-controller and its peripherals. This section lists common
+commands available for that purpose. Unlike most micro-controller
+commands, these commands run as soon as they are received and they do
+not require any particular setup.
+
+These commands are most useful in the "custom" block of the "mcu"
+section of the printer configuration file. This feature is typically
+used to configure the initial settings of LEDs, to configure
+micro-stepping pins, to configure a digipot, etc.
+
+Several of these commands will take a "pin=%u" parameter. The
+low-level micro-controller software uses integer encodings of the
+hardware pin numbers, but to make things more readable the host will
+translate human readable pin names (eg, "PA3") to their equivalent
+integer encodings. By convention, any parameter named "pin" or that
+has a "_pin" suffix will use pin name translation by the
+host. Similarly, several commands take time parameters specified in
+clock ticks. One can specify a value for these parameters in seconds
+using the "TICKS()" macro - for example "cycle_ticks=TICKS(0.001)"
+would result in "cycle_ticks=16000" on a micro-controller with a 16Mhz
+clock.
+
+Common startup commands:
+
+* `set_digital_out pin=%u value=%c` : This command immediately
+  configures the given pin as a digital out GPIO and it sets it to
+  either a low level (value=0) or a high level (value=1). This command
+  may be useful for configuring the initial value of LEDs and for
+  configuring the initial value of stepper driver micro-stepping pins.
+
+* `set_pwm_out pin=%u cycle_ticks=%u value=%c` : This command will
+  immediately configure the given pin to use hardware based
+  pulse-width-modulation (PWM) with the given number of
+  cycle_ticks. The "cycle_ticks" is the number of MCU clock ticks each
+  power on and power off cycle should last. A cycle_ticks value of 1
+  can be used to request the fastest possible cycle time. The "value"
+  parameter is between 0 and 255 with 0 indicating a full off state
+  and 255 indicating a full on state. This command may be useful for
+  enabling CPU and nozzle cooling fans.
+
+* `send_spi_message pin=%u msg=%*s` : This command can be used to
+  transmit messages to a serial-peripheral-interface (SPI) component
+  connected to the micro-controller. It has been used to configure the
+  startup settings of AD5206 digipots. The 'pin' parameter specifies
+  the chip select line to use during the transmission. The 'msg'
+  indicates the binary message to transmit to the given chip.
+
+Low-level micro-controller configuration
+========================================
+
+Most commands in the micro-controller require an initial setup before
+they can be successfully invoked. This section provides an overview of
+the configuration process. This section and the following sections are
+likely only of interest to developers interested in the internal
+details of Klipper.
+
+When the host first connects to the micro-controller it always starts
+by obtaining a data dictionary (see [protocol](Protocol.md) for more
+information). After the data dictionary is obtained the host will
+check if the micro-controller is in a "configured" state and configure
+it if not. Configuration involves the following phases:
+
+* `get_config` : The host starts by checking if the micro-controller
+  is already configured. The micro-controller responds to this command
+  with a "config" response message. The micro-controller software
+  always starts in an unconfigured state at power-on. It remains in
+  this state until the host completes the configuration processes (by
+  issuing a finalize_config command). If the micro-controller is
+  already configured from a previous session (and is configured with
+  the desired settings) then no further action is needed by the host
+  and the configuration process ends successfully.
+
+* `allocate_oids count=%c` : This command is issued to inform the
+  micro-controller of the maximum number of object-ids (oid) that the
+  host requires. It is only valid to issue this command once. An oid
+  is an integer identifier allocated to each stepper, each endstop,
+  and each schedulable gpio pin. The host determines in advance the
+  number of oids it will require to operate the hardware and passes
+  this to the micro-controller so that it may allocate sufficient
+  memory to store a mapping from oid to internal object.
+
+* `config_XXX oid=%c ...` : By convention any command starting with
+  the "config_" prefix creates a new micro-controller object and
+  assigns the given oid to it. For example, the config_digital_out
+  command will configure the specified pin as a digital output GPIO
+  and create an internal object that the host can use to schedule
+  changes to the given GPIO. The oid parameter passed into the config
+  command is selected by the host and must be between zero and the
+  maximum count supplied in the allocate_oids command. The config
+  commands may only be run when the micro-controller is not in a
+  configured state (ie, prior to the host sending finalize_config) and
+  after the allocate_oids command has been sent.
+
+* `finalize_config crc=%u` : The finalize_config command transitions
+  the micro-controller from an unconfigured state to a configured
+  state. The crc parameter passed to the micro-controller is stored
+  and provided back to the host in "config" response messages. By
+  convention, the host takes a 32bit CRC of the configuration it will
+  request and at the start of subsequent communication sessions it
+  checks that the CRC stored in the micro-controller exactly matches
+  its desired CRC. If the CRC does not match then the host knows the
+  micro-controller has not been configured in the state desired by the
+  host.
+
+Common micro-controller objects
+-------------------------------
+
+This section lists some commonly used config commands.
+
+* `config_digital_out oid=%c pin=%u default_value=%c
+  max_duration=%u` : This command creates an internal micro-controller
+  object for the given GPIO 'pin'. The pin will be configured in
+  digital output mode and set to an initial value as specified by
+  'default_value' (0 for low, 1 for high). Creating a digital_out
+  object allows the host to schedule GPIO updates for the given pin at
+  specified times (see the schedule_digital_out command described
+  below). Should the micro-controller software go into shutdown mode
+  then all configured digital_out objects will be set back to their
+  default values. The 'max_duration' parameter is used to implement a
+  safety check - if it is non-zero then it is the maximum number of
+  clock ticks that the host may set the given GPIO to a non-default
+  value without further updates. For example, if the default_value is
+  zero and the max_duration is 16000 then if the host sets the gpio to
+  a value of one then it must schedule another update to the gpio pin
+  (to either zero or one) within 16000 clock ticks. This safety
+  feature can be used with heater pins to ensure the host does not
+  enable the heater and then go off-line.
+
+* `config_pwm_out oid=%c pin=%u cycle_ticks=%u default_value=%c
+  max_duration=%u` : This command creates an internal object for
+  hardware based PWM pins that the host may schedule updates for. Its
+  usage is analogous to config_digital_out - see the description of
+  the 'set_pwm_out' and 'config_digital_out' commands for parameter
+  description.
+
+* `config_soft_pwm_out oid=%c pin=%u cycle_ticks=%u default_value=%c
+  max_duration=%u` : This command creates an internal micro-controller
+  object for software implemented PWM. Unlike hardware pwm pins, a
+  software pwm object does not require any special hardware support
+  (other than the ability to configure the pin as a digital output
+  GPIO). Because the output switching is implemented in the
+  micro-controller software, it is recommended that the cycle_ticks
+  parameter correspond to a time of 10ms or greater. See the
+  description of the 'set_pwm_out' and 'config_digital_out' commands
+  for parameter description.
+
+* `config_analog_in oid=%c pin=%u` : This command is used to configure
+  a pin in analog input sampling mode. Once configured, the pin can be
+  sampled at regular interval using the query_analog_in command (see
+  below).
+
+* `config_stepper oid=%c step_pin=%c dir_pin=%c min_stop_interval=%u
+  invert_step=%c` : This command creates an internal stepper
+  object. The 'step_pin' and 'dir_pin' parameters specify the step and
+  direction pins respectively; this command will configure them in
+  digital output mode. The 'invert_step' parameter specifies whether a
+  step occurs on a rising edge (invert_step=0) or falling edge
+  (invert_step=1). The 'min_stop_interval' implements a safety
+  feature - it is checked when the micro-controller finishes all moves
+  for a stepper - if it is non-zero it specifies the minimum number of
+  clock ticks since the last step. It is used as a check on the
+  maximum stepper velocity that a stepper may have before stopping.
+
+* `config_end_stop oid=%c pin=%c pull_up=%c stepper_count=%c` : This
+  command creates an internal "endstop" object. It is used to specify
+  the endstop pins and to enable "homing" operations (see the
+  end_stop_home command below). The command will configure the
+  specified pin in digital input mode. The 'pull_up' parameter
+  determines whether hardware provided pullup resistors for the pin
+  (if available) will be enabled. The 'stepper_count' parameter
+  specifies the maximum number of steppers that this endstop may need
+  to halt during a homing operation (see end_stop_home below).
+
+Common commands
+===============
+
+This section lists some commonly used run-time commands. It is likely
+only of interest to developers looking to gain insight into Klipper.
+
+* `schedule_digital_out oid=%c clock=%u value=%c` : This command will
+  schedule a change to a digital output GPIO pin at the given clock
+  time. To use this command a 'config_digital_out' command with the
+  same 'oid' parameter must have been issued during micro-controller
+  configuration.
+
+* `schedule_pwm_out oid=%c clock=%u value=%c` : Schedules a change to
+  a hardware PWM output pin. See the 'schedule_digital_out' and
+  'config_pwm_out' commands for more info.
+
+* `schedule_soft_pwm_out oid=%c clock=%u value=%c` : Schedules a
+  change to a software PWM output pin. See the 'schedule_digital_out'
+  and 'config_soft_pwm_out' commands for more info.
+
+* `query_analog_in oid=%c clock=%u sample_ticks=%u sample_count=%c
+  rest_ticks=%u min_value=%hu max_value=%hu` : This command sets up a
+  recurring schedule of analog input samples. To use this command a
+  'config_analog_in' command with the same 'oid' parameter must have
+  been issued during micro-controller configuration. The samples will
+  start as of 'clock' time, it will report on the obtained value every
+  'rest_ticks' clock ticks, it will over-sample 'sample_count' number
+  of times, and it will pause 'sample_ticks' number of clock ticks
+  between over-sample samples. The 'min_value' and 'max_value'
+  parameters implement a safety feature - the micro-controller
+  software will verify the sampled value (after any oversampling) is
+  always between the supplied range. This is intended for use with
+  pins attached to thermistors controlling heaters - it can be used to
+  check that a heater is within a temperature range.
+
+* `get_status` : This command causes the micro-controller to generate
+  a "status" response message. The host sends this command once a
+  second to obtain the value of the micro-controller clock and to
+  estimate the drift between host and micro-controller clocks. It
+  enables the host to accurately estimate the micro-controller clock.
+
+Stepper commands
+----------------
+
+* `queue_step oid=%c interval=%u count=%hu add=%hi` : This command
+  schedules 'count' number of steps for the given stepper, with
+  'interval' number of clock ticks between each step. The first step
+  will be 'interval' number of clock ticks since the last scheduled
+  step for the given stepper. If 'add' is non-zero then the interval
+  will be adjusted by 'add' amount after each step. This command
+  appends the given interval/count/add sequence to a per-stepper
+  queue. There may be hundreds of these sequences queued during normal
+  operation. New sequence are appended to the end of the queue and as
+  each sequence completes its 'count' number of steps it is popped
+  from the front of the queue. This system allows the micro-controller
+  to queue potentially hundreds of thousands of steps - all with
+  reliable and predictable schedule times.
+
+* `set_next_step_dir oid=%c dir=%c` : This command specifies the value
+  of the dir_pin that the next queue_step command will use.
+
+* `reset_step_clock oid=%c clock=%u` : Normally, step timing is
+  relative to the last step for a given stepper. This command resets
+  the clock so that the next step is relative to the supplied 'clock'
+  time. The host usually only sends this command at the start of a
+  print.
+
+* `stepper_get_position oid=%c` : This command causes the
+  micro-controller to generate a "stepper_position" response message
+  with the stepper's current position. The position is the total
+  number of steps generated with dir=1 minus the total number of steps
+  generated with dir=0.
+
+* `end_stop_home oid=%c clock=%u rest_ticks=%u pin_value=%c` : This
+  command is used during stepper "homing" operations. To use this
+  command a 'config_end_stop' command with the same 'oid' parameter
+  must have been issued during micro-controller configuration. When
+  this command is invoked, the micro-controller will sample the
+  endstop pin every 'rest_ticks' clock ticks and check if it has a
+  value equal to 'pin_value'. If the value matches then the movement
+  queue for the associated stepper will be cleared and the stepper
+  will come to an immediate halt. The host uses this command to
+  implement homing - the host instructs the endstop to sample for the
+  endstop trigger and then it issues a series of queue_step commands
+  to move a stepper towards the endstop. Once the stepper hits the
+  endstop, the trigger will be detected, the movement halted, and the
+  host notified.
+
+### Move queue
+
+Each queue_step command utilizes an entry in the micro-controller
+"move queue". This queue is allocated when it receives the
+"finalize_config" command, and it reports the number of available
+queue entries in "config" response messages.
+
+It is the responsibility of the host to ensure that there is available
+space in the queue before sending a queue_step command. The host does
+this by calculating when each queue_step command completes and
+scheduling new queue_step commands accordingly.

docs/Overview.md

@@ -1,18 +1,35 @@
-See [installation](Installation.md) for information on compiling,
-installing, and running Klipper. Read [features](Features.md) for a
-high-level description of useful capabilities. The history of releases
-is available at [releases](Releases.md).
+Welcome to the Klipper documentation. There are two parts to Klipper -
+code that runs on a micro-controller and code that runs on a "host"
+machine. The host code is intended to run on a low-cost
+general-purpose machine such as a Raspberry Pi, while the
+micro-controller code is intended to run on commodity micro-controller
+chips. Read [features](Features.md) for reasons to use Klipper. See
+[installation](Installation.md) to get started with Klipper.
+
+The Klipper configuration is stored in a simple text file on the host
+machine. The [config/example.cfg](../config/example.cfg) file serves
+as a reference for the config file. The
+[Pressure Advance](Pressure_Advance.md) document contains information
+on tuning the pressure advance config.
+
+The [kinematics](Kinematics.md) document provides some technical
+details on how Klipper implements motion.
+
+The history of Klipper releases is available at
+[releases](Releases.md).
+
+Developer Documentation
+=======================
 
 There are also several documents available for developers interested
-in understanding how Klipper works:
+in understanding how Klipper works. Start with the
+[code overview](Code_Overview.md) document - it provides information
+on the structure and layout of the Klipper code.
 
-See [code overview](Code_Overview.md) for information on the structure
-and layout of the Klipper code.
-
-See [protocol](Protocol.md) for information on the messaging protocol
-between host and firmware. See also
-[firmware commands](Firmware_Commands.md) for a high-level description
-of common commands implemented in the firmware.
+See [protocol](Protocol.md) for information on the low-level messaging
+protocol between host and micro-controller. See also
+[MCU commands](MCU_Commands.md) for a description of low-level
+commands implemented in the micro-controller software.
 
 See [debugging](Debugging.md) for information on how to test and debug
 Klipper.

docs/Pressure_Advance.md

@@ -0,0 +1,74 @@
+This document provides information on tuning the "pressure advance"
+configuration variables for a particular nozzle and filament. The
+pressure advance feature can be helpful in reducing ooze. For more
+information on how pressure advance is implemented see the
+[kinematics](Kinematics.md) document.
+
+Tuning pressure advance
+=======================
+
+Pressure advance does two useful things - it reduces ooze during
+non-extrude moves and it reduces blobbing during cornering. This guide
+uses the second feature (reducing blobbing during cornering) as a
+mechanism for measuring and tuning the pressure advance configuration.
+
+Start by changing the extruder section of the config file so that
+pressure_advance is set to 0.0. (Make sure to issue a RESTART command
+after each update to the config file so that the new configuration
+takes effect.) Then print at least 10 layers of a large hollow square
+at high speed (eg, 100mm/s). See
+[docs/prints/square.stl](prints/square.stl) file for an STL file that
+one may use. While the object is printing, make a note of which
+direction the head is moving during external perimeters. What many
+people see here is blobbing occurring at the corners - extra filament
+at the corner in the direction the head travels followed by a possible
+lack of filament on the side immediately after that corner:
+
+![corner-blob](img/corner-blob.jpg)
+
+This blobbing is the result of pressure in the extruder being released
+as a blob when the head slows down to corner.
+
+The next step is to set pressure_advance_lookahead_time to 0.0, slowly
+increase pressure_advance (eg, start with 0.05), and reprint the test
+object. (Be sure to issue RESTART between each config change.) The
+goal is to attempt to eliminate the blobbing during cornering. (With
+pressure advance, the extruder will retract when the head slows down,
+thus countering the pressure buildup and ideally eliminate the
+blobbing.) If a test run is done with a pressure_advance setting that
+is too high, one typically sees a dimple in the corner followed by
+possible blobbing after the corner (too much filament is retracted
+during slow down and then too much filament is extruded during the
+following speed up after cornering):
+
+![corner-dimple](img/corner-dimple.jpg)
+
+The goal is to find the smallest pressure_advance value that results
+in good quality corners:
+
+![corner-good](img/corner-good.jpg)
+
+Typical pressure_advance values are between 0.05 and 0.20 (the high
+end usually only with bowden extruders).
+
+Once a good pressure_advance value is found, return
+pressure_advance_lookahead_time to its default (0.010). This parameter
+controls how far in advance to check if a head slow-down is
+immediately followed by a speed-up - it reduces pointless pressure
+changes in the head. It's possible to tune this - higher values will
+decrease the number of pressure changes in the nozzle at the expense
+of permitting more blobbing during cornering. (Tuning this value is
+unlikely to impact ooze.) The default of 10ms should work well on most
+printers.
+
+Although this tuning exercise directly improves the quality of
+corners, it's worth remembering that a good pressure advance
+configuration can reduce ooze throughout the print.
+
+Finally, once pressure_advance is tuned in Klipper, it may still be
+useful to configure a small retract value in the slicer (eg, 0.75mm)
+and to utilize the slicer's "wipe on retract option" if available.
+These slicer settings may help counteract ooze caused by filament
+cohesion (filament pulled out of the nozzle due to the stickiness of
+the plastic). It is recommended to disable the slicer's "z-lift on
+retract" option.

docs/Protocol.md

@@ -1,8 +1,9 @@
-The Klipper transmission protocol can be thought of, at a high level,
-as a series of command and response strings that are compressed,
-transmitted over a serial line, and then processed at the receiving
-side. An example series of commands in uncompressed human-readable
-format might look like:
+The Klipper messaging protocol is used for low-level communication
+between the Klipper host software and the Klipper micro-controller
+software. At a high level the protocol can be thought of as a series
+of command and response strings that are compressed, transmitted, and
+then processed at the receiving side. An example series of commands in
+uncompressed human-readable format might look like:
 
 ```
 set_digital_out pin=86 value=1
@@ -12,34 +13,35 @@ queue_step oid=7 interval=7458 count=10 add=331
 queue_step oid=7 interval=11717 count=4 add=1281
 ```
 
-See the [firmware commands](Firmware_Commands.md) document for
-information on available commands. See the [debugging](Debugging.md)
-document for information on how to translate a G-Code file into its
-corresponding human-readable firmware commands.
+See the [mcu commands](MCU_Commands.md) document for information on
+available commands. See the [debugging](Debugging.md) document for
+information on how to translate a G-Code file into its corresponding
+human-readable micro-controller commands.
 
-This page provides a high-level description of the Klipper
-transmission protocol itself. It describes how messages are declared,
-encoded in binary format (the "compression" scheme), and transmitted.
+This page provides a high-level description of the Klipper messaging
+protocol itself. It describes how messages are declared, encoded in
+binary format (the "compression" scheme), and transmitted.
 
 The goal of the protocol is to enable an error-free communication
-channel between the host and firmware that is low-latency,
-low-bandwidth, and low-complexity for the firmware.
+channel between the host and micro-controller that is low-latency,
+low-bandwidth, and low-complexity for the micro-controller.
 
-Firmware Interface
-==================
+Micro-controller Interface
+==========================
 
 The Klipper transmission protocol can be thought of as a
 [RPC](https://en.wikipedia.org/wiki/Remote_procedure_call) mechanism
-between firmware and host. The firmware declares the commands that the
-host may invoke along with the response messages that it can
-generate. The host uses that information to command the firmware to
-perform actions and to interpret the results.
+between micro-controller and host. The micro-controller software
+declares the commands that the host may invoke along with the response
+messages that it can generate. The host uses that information to
+command the micro-controller to perform actions and to interpret the
+results.
 
 Declaring commands
 ------------------
 
-The firmware declares a "command" by using the DECL_COMMAND() macro in
-the C code. For example:
+The micro-controller software declares a "command" by using the
+DECL_COMMAND() macro in the C code. For example:
 
 ```
 DECL_COMMAND(command_set_digital_out, "set_digital_out pin=%u value=%c");
@@ -48,11 +50,11 @@ DECL_COMMAND(command_set_digital_out, "set_digital_out pin=%u value=%c");
 The above declares a command named "set_digital_out". This allows the
 host to "invoke" this command which would cause the
 command_set_digital_out() C function to be executed in the
-firmware. The above also indicates that the command takes two integer
-parameters. When the command_set_digital_out() C code is executed, it
-will be passed an array containing these two integers - the first
-corresponding to the 'pin' and the second corresponding to the
-'value'.
+micro-controller. The above also indicates that the command takes two
+integer parameters. When the command_set_digital_out() C code is
+executed, it will be passed an array containing these two integers -
+the first corresponding to the 'pin' and the second corresponding to
+the 'value'.
 
 In general, the parameters are described with printf() style syntax
 (eg, "%u"). The formatting directly corresponds to the human-readable
@@ -63,64 +65,61 @@ documentation. In this example, the "%c" is also used as documentation
 to indicate the expected integer is 1 byte in size (the declared
 integer size does not impact the parsing or encoding).
 
-At firmware compile time, the build will collect all commands declared
-with DECL_COMMAND(), determine their parameters, and arrange for them
-to be callable.
+The micro-controller build will collect all commands declared with
+DECL_COMMAND(), determine their parameters, and arrange for them to be
+callable.
 
 Declaring responses
 -------------------
 
-To send information from the firmware to the host a "response" is
-generated. These are both declared and transmitted using the sendf() C
-macro. For example:
+To send information from the micro-controller to the host a "response"
+is generated. These are both declared and transmitted using the
+sendf() C macro. For example:
 
 ```
 sendf("status clock=%u status=%c", sched_read_time(), sched_is_shutdown());
 ```
 
 The above transmits a "status" response message that contains two
-integer parameters ("clock" and "status"). At firmware compile time
-the build automatically finds all sendf() calls and generates encoders
-for them. The first parameter of the sendf() function describes the
+integer parameters ("clock" and "status"). The micro-controller build
+automatically finds all sendf() calls and generates encoders for
+them. The first parameter of the sendf() function describes the
 response and it is in the same format as command declarations.
 
 The host can arrange to register a callback function for each
 response. So, in effect, commands allow the host to invoke C functions
-in the firmware and responses allow the firmware to invoke code in the
-host.
+in the micro-controller and responses allow the micro-controller
+software to invoke code in the host.
 
-The firmware should only invoke sendf() from command or task handlers,
-and it should not be invoked from interrupts or timers. The firmware
-does not need to issue a sendf() in response to a received command, it
-is not limited in the number of times sendf() may be invoked, and it
-may invoke sendf() at any time from a task handler.
+The sendf() macro should only be invoked from command or task
+handlers, and it should not be invoked from interrupts or timers. The
+code does not need to issue a sendf() in response to a received
+command, it is not limited in the number of times sendf() may be
+invoked, and it may invoke sendf() at any time from a task handler.
 
 ### Output responses
 
-To simplify debugging, the firmware also has an output() C
-function. For example:
+To simplify debugging, there is also has an output() C function. For
+example:
 
 ```
 output("The value of %u is %s with size %u.", x, buf, buf_len);
 ```
 
 The output() function is similar in usage to printf() - it is intended
-to generate and format arbitrary messages for human consumption. It is
-a wrapper around sendf() and as with sendf() it should not be called
-from interrupts or timers.
+to generate and format arbitrary messages for human consumption.
 
 Declaring constants
 -------------------
 
-The firmware can also define constants to be exported.  For example,
-the following:
+Constants can also be exported. For example, the following:
 
 ```
 DECL_CONSTANT(SERIAL_BAUD, 250000);
 ```
 
 would export a constant named "SERIAL_BAUD" with a value of 250000
-from the firmware to the host.
+from the micro-controller to the host.
 
 Low-level message encoding
 ==========================
@@ -132,9 +131,9 @@ the transmission system.
 Message Blocks
 --------------
 
-All data sent from host to firmware and vice-versa are contained in
-"message blocks". A message block has a two byte header and a three
-byte trailer.  The format of a message block is:
+All data sent from host to micro-controller and vice-versa are
+contained in "message blocks". A message block has a two byte header
+and a three byte trailer. The format of a message block is:
 
 ```
 <1 byte length><1 byte sequence><n-byte content><2 byte crc><1 byte sync>
@@ -162,10 +161,11 @@ present in the message block content.
 Message Block Contents
 ----------------------
 
-Each message block sent from host to firmware contains a series of
-zero or more message commands in its contents. Each command starts
-with a Variable Length Quantity (VLQ) encoded integer command-id
-followed by zero or more VLQ parameters for the given command.
+Each message block sent from host to micro-controller contains a
+series of zero or more message commands in its contents. Each command
+starts with a [Variable Length Quantity](#variable-length-quantities)
+(VLQ) encoded integer command-id followed by zero or more VLQ
+parameters for the given command.
 
 As an example, the following four commands might be placed in a single
 message block:
@@ -184,21 +184,22 @@ and encoded into the following eight VLQ integers:
 ```
 
 In order to encode and parse the message contents, both the host and
-firmware must agree on the command ids and the number of parameters
-each command has. So, in the above example, both the host and firmware
-would know that "id_set_digital_out" is always followed by two
-parameters, and "id_get_config" and "id_get_status" have zero
-parameters. The host and firmware share a "data dictionary" that maps
-the command descriptions (eg, "set_digital_out pin=%u value=%c") to
-their integer command-ids. When processing the data, the parser will
-know to expect a specific number of VLQ encoded parameters following a
-given command id.
+micro-controller must agree on the command ids and the number of
+parameters each command has. So, in the above example, both the host
+and micro-controller would know that "id_set_digital_out" is always
+followed by two parameters, and "id_get_config" and "id_get_status"
+have zero parameters. The host and micro-controller share a "data
+dictionary" that maps the command descriptions (eg, "set_digital_out
+pin=%u value=%c") to their integer command-ids. When processing the
+data, the parser will know to expect a specific number of VLQ encoded
+parameters following a given command id.
 
-The message contents for blocks sent from firmware to host follow the
-same format. The identifiers in these messages are "response ids", but
-they serve the same purpose and follow the same encoding rules. In
-practice, message blocks sent from the firmware to the host never
-contain more than one response in the message block contents.
+The message contents for blocks sent from micro-controller to host
+follow the same format. The identifiers in these messages are
+"response ids", but they serve the same purpose and follow the same
+encoding rules. In practice, message blocks sent from the
+micro-controller to the host never contain more than one response in
+the message block contents.
 
 ### Variable Length Quantities
 
@@ -230,60 +231,62 @@ the length as a VLQ encoded integer followed by the contents itself:
 ```
 
 The command descriptions found in the data dictionary allow both the
-host and firmware to know which command parameters use simple VLQ
-encoding and which parameters use string encoding.
+host and micro-controller to know which command parameters use simple
+VLQ encoding and which parameters use string encoding.
 
 Data Dictionary
 ===============
 
 In order for meaningful communications to be established between
-firmware and host, both sides must agree on a "data dictionary". This
-data dictionary contains the integer identifiers for commands and
-responses along with their descriptions.
+micro-controller and host, both sides must agree on a "data
+dictionary". This data dictionary contains the integer identifiers for
+commands and responses along with their descriptions.
 
-At compile time the firmware build uses the contents of DECL_COMMAND()
-and sendf() macros to generate the data dictionary. The build
+The micro-controller build uses the contents of DECL_COMMAND() and
+sendf() macros to generate the data dictionary. The build
 automatically assigns unique identifiers to each command and
-response. This system allows both the host and firmware code to
-seamlessly use descriptive human-readable names while still using
+response. This system allows both the host and micro-controller code
+to seamlessly use descriptive human-readable names while still using
 minimal bandwidth.
 
 The host queries the data dictionary when it first connects to the
-firmware. Once the host downloads the data dictionary from the
-firmware, it uses that data dictionary to encode all commands and to
-parse all responses from the firmware. The host must therefore handle
-a dynamic data dictionary. However, to keep the firmware simple, the
-firmware always uses its static (compiled in) data dictionary.
+micro-controller. Once the host downloads the data dictionary from the
+micro-controller, it uses that data dictionary to encode all commands
+and to parse all responses from the micro-controller. The host must
+therefore handle a dynamic data dictionary. However, to keep the
+micro-controller software simple, the micro-controller always uses its
+static (compiled in) data dictionary.
 
 The data dictionary is queried by sending "identify" commands to the
-firmware. The firmware will respond to each identify command with an
-"identify_response" message. Since these two commands are needed prior
-to obtaining the data dictionary, their integer ids and parameter
-types are hard-coded in both the firmware and the host. The
-"identify_response" response id is 0, the "identify" command id
-is 1. Other than having hard-coded ids the identify command and its
-response are declared and transmitted the same way as other commands
-and responses. No other command or response is hard-coded.
+micro-controller. The micro-controller will respond to each identify
+command with an "identify_response" message. Since these two commands
+are needed prior to obtaining the data dictionary, their integer ids
+and parameter types are hard-coded in both the micro-controller and
+the host. The "identify_response" response id is 0, the "identify"
+command id is 1. Other than having hard-coded ids the identify command
+and its response are declared and transmitted the same way as other
+commands and responses. No other command or response is hard-coded.
 
 The format of the transmitted data dictionary itself is a zlib
-compressed JSON string. The firmware compile process generates the
-string, compresses it, and stores it in the text section of the
-firmware. The data dictionary can be much larger than the maximum
-message block size - the host downloads it by sending multiple
-identify commands requesting progressive chunks of the data
+compressed JSON string. The micro-controller build process generates
+the string, compresses it, and stores it in the text section of the
+micro-controller flash. The data dictionary can be much larger than
+the maximum message block size - the host downloads it by sending
+multiple identify commands requesting progressive chunks of the data
 dictionary. Once all chunks are obtained the host will assemble the
 chunks, uncompress the data, and parse the contents.
 
 In addition to information on the communication protocol, the data
-dictionary also contains firmware version, constants (as defined by
-DECL_CONSTANT), and static strings.
+dictionary also contains the software version, constants (as defined
+by DECL_CONSTANT), and static strings.
 
 Static Strings
 --------------
 
 To reduce bandwidth the data dictionary also contains a set of static
-strings known to the firmware. This is useful when sending messages
-from firmware to host. For example, if the firmware were to run:
+strings known to the micro-controller. This is useful when sending
+messages from micro-controller to host. For example, if the
+micro-controller were to run:
 
 ```
 shutdown("Unable to handle command");
@@ -296,22 +299,22 @@ to their associated human-readable strings.
 Message flow
 ============
 
-Message commands sent from host to firmware are intended to be
-error-free. The firmware will check the CRC and sequence numbers in
-each message block to ensure the commands are accurate and
-in-order. The firmware always processes message blocks in-order -
-should it receive a block out-of-order it will discard it and any
-other out-of-order blocks until it receives blocks with the correct
-sequencing.
+Message commands sent from host to micro-controller are intended to be
+error-free. The micro-controller will check the CRC and sequence
+numbers in each message block to ensure the commands are accurate and
+in-order. The micro-controller always processes message blocks
+in-order - should it receive a block out-of-order it will discard it
+and any other out-of-order blocks until it receives blocks with the
+correct sequencing.
 
 The low-level host code implements an automatic retransmission system
-for lost and corrupt message blocks sent to the firmware. To
-facilitate this, the firmware transmits an "ack message block" after
-each successfully received message block. The host schedules a timeout
-after sending each block and it will retransmit should the timeout
-expire without receiving a corresponding "ack". In addition, if the
-firmware detects a corrupt or out-of-order block it may transmit a
-"nak message block" to facilitate fast retransmission.
+for lost and corrupt message blocks sent to the micro-controller. To
+facilitate this, the micro-controller transmits an "ack message block"
+after each successfully received message block. The host schedules a
+timeout after sending each block and it will retransmit should the
+timeout expire without receiving a corresponding "ack". In addition,
+if the micro-controller detects a corrupt or out-of-order block it may
+transmit a "nak message block" to facilitate fast retransmission.
 
 An "ack" is a message block with empty content (ie, a 5 byte message
 block) and a sequence number greater than the last received host
@@ -326,15 +329,15 @@ in the event of transmission latency. The timeout, retransmit,
 windowing, and ack mechanism are inspired by similar mechanisms in
 [TCP](https://en.wikipedia.org/wiki/Transmission_Control_Protocol).
 
-In the other direction, message blocks sent from firmware to host are
-designed to be error-free, but they do not have assured
+In the other direction, message blocks sent from micro-controller to
+host are designed to be error-free, but they do not have assured
 transmission. (Responses should not be corrupt, but they may go
-missing.) This is done to keep the implementation in the firmware
-simple. There is no automatic retransmission system for responses -
-the high-level code is expected to be capable of handling an
-occasional missing response (usually by re-requesting the content or
-setting up a recurring schedule of response transmission). The
-sequence number field in message blocks sent to the host is always one
-greater than the last received sequence number of message blocks
-received from the host. It is not used to track sequences of response
-message blocks.
+missing.) This is done to keep the implementation in the
+micro-controller simple. There is no automatic retransmission system
+for responses - the high-level code is expected to be capable of
+handling an occasional missing response (usually by re-requesting the
+content or setting up a recurring schedule of response
+transmission). The sequence number field in message blocks sent to the
+host is always one greater than the last received sequence number of
+message blocks received from the host. It is not used to track
+sequences of response message blocks.

docs/README.md

@@ -0,0 +1,2 @@
+Welcome to the Klipper documentation. The
+[overview document](Overview.md) is a good starting point.

docs/Releases.md

@@ -1,6 +1,26 @@
 History of Klipper releases. Please see
 [installation](Installation.md) for information on installing Klipper.
 
+Klipper 0.4.0
+=============
+
+Available on 20170503. Major changes in this release:
+
+* Improved installation on Raspberry Pi machines. Most of the install
+  is now scripted.
+* Support for corexy kinematics
+* Documentation updates: New Kinematics document, new Pressure Advance
+  tuning guide, new example config files, and more
+* Stepper performance improvements (20Mhz AVRs over 175K steps per
+  second, Arduino Due over 460K)
+* Support for automatic micro-controller resets. Support for resets
+  via toggling USB power on Raspberry Pi.
+* The pressure advance algorithm now works with look-ahead to reduce
+  pressure changes during cornering.
+* Support for limiting the top speed of short zigzag moves
+* Support for AD595 sensors
+* Several bug fixes and code cleanups
+
 Klipper 0.3.0
 =============
 

docs/Todo.md

@@ -1,5 +1,5 @@
-Klipper is currently in an experimental state. There are several
-features still to be implemented.  In no particular order:
+There are several features still to be implemented in Klipper. In no
+particular order:
 
 Host user interaction
 =====================
@@ -9,13 +9,6 @@ Host user interaction
   find the error) and errors written to the log can be non-obvious to
   a user.
 
-* Improve startup:
-
- * Provide startup scripts so that Klippy can startup at system
-   bootup.
-
- * Allow loading of a new config without having to restart the mcu.
-
 * Improve gcode interface:
 
  * Provide a better way to handle print nozzle z offsets. The M206
@@ -28,12 +21,6 @@ Host user interaction
 
 * Improve logging:
 
- * Automatically roll Klippy log files. The default log file should
-   have the current date in the log file name.
-
- * Report the Klippy git version in log file. Log the contents of the
-   config file at startup.
-
  * Possibly collate and report the statistics messages in the log in a
    more friendly way.
 
@@ -44,12 +31,12 @@ Host user interaction
 Safety features
 ===============
 
-* Support loading a valid step range into the firmware after
-  homing. This would provide a sanity check in the firmware that would
-  reduce the risk of the host commanding a stepper motor past its
-  valid step range. To maintain high efficiency in the firmware, the
-  firmware would only need to check periodically (eg, every 100ms)
-  that the stepper is in range.
+* Support loading a valid step range into the micro-controller
+  software after homing. This would provide a sanity check in the
+  micro-controller that would reduce the risk of the host commanding a
+  stepper motor past its valid step range. To maintain high
+  efficiency, the micro-controller would only need to check
+  periodically (eg, every 100ms) that the stepper is in range.
 
  * Possibly support periodically querying the endstop switches and use
    multiple step ranges depending on the switch state. This would
@@ -61,17 +48,14 @@ Safety features
   can be useful to detect a sensor failure (eg, thermistor short) that
   could otherwise cause the PID to command excessive heating.
 
-* Possibly implement host based checking on the ratio between extrude
-  amount and head movement.
- * Enforce acceleration and speed limits on extruder stepper motor.
-
 Testing features
 ================
 
 * Complete the host based simulator. It's possible to compile the
-  firmware for a "host simulator", but that simulator doesn't do
-  anything currently. It would be useful to expand the code to support
-  more error checks, kinematic simulations, and improved logging.
+  micro-controller for a "host simulator", but that simulator doesn't
+  do anything currently. It would be useful to expand the code to
+  support more error checks, kinematic simulations, and improved
+  logging.
 
 Documentation
 =============
@@ -81,20 +65,15 @@ Documentation
 * Add documentation describing how to perform bed-leveling accurately
   in Klipper. Improve description of stepper phase based bed leveling.
 
-* Document the kinematic formulas in Klippy. Document how acceleration
-  and jerk limits are enforced.
-
-* Document how one can tune the pressure advance setting.
-
 Hardware features
 =================
 
-* Port firmware to more architectures:
+* Port to additional micro-controller architectures:
  * Beagle Bone Black PRU
  * Smoothieboard / NXP LPC1769 (ARM cortex-M3)
  * Unix based scheduling; Unix based real-time scheduling
 
-* Support for additional kinematics: scara, corexy, etc.
+* Support for additional kinematics: scara, etc.
 
 * Support shared motor enable GPIO lines.
 
@@ -108,11 +87,6 @@ Hardware features
   it would also be useful to handle panels already hardwired to the
   micro-controller.)
 
-* The raspberry pi has the ability to cut power to its USB ports. This
-  feature is useful for resetting micro-controllers that are powered
-  over USB. It would be useful to have a high-level command interface
-  in Klippy to request a micro-controller reset via this mechanism.
-
 * Possibly support printers using multiple micro-controllers.
 
 Misc features

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docs/prints/square.scad

@@ -0,0 +1,14 @@
+// Test square
+//
+// Generate STL using OpenSCAD:
+//   openscad square.scad -o square.stl
+
+square_width = 5;
+square_size = 60;
+square_height = 5;
+
+difference() {
+  cube([square_size, square_size, square_height]);
+  translate([square_width, square_width, -1])
+    cube([square_size-2*square_width, square_size-2*square_width, square_height+2]);
+}

docs/prints/square.stl

@@ -0,0 +1,226 @@
+solid OpenSCAD_Model
+  facet normal -1 0 0
+    outer loop
+      vertex 0 0 0
+      vertex 0 60 5
+      vertex 0 60 0
+    endloop
+  endfacet
+  facet normal -1 -0 0
+    outer loop
+      vertex 0 60 5
+      vertex 0 0 0
+      vertex 0 0 5
+    endloop
+  endfacet
+  facet normal 0 0 1
+    outer loop
+      vertex 60 60 5
+      vertex 55 55 5
+      vertex 60 0 5
+    endloop
+  endfacet
+  facet normal 0 0 1
+    outer loop
+      vertex 60 60 5
+      vertex 5 55 5
+      vertex 55 55 5
+    endloop
+  endfacet
+  facet normal 0 0 1
+    outer loop
+      vertex 5 55 5
+      vertex 0 60 5
+      vertex 5 5 5
+    endloop
+  endfacet
+  facet normal -0 0 1
+    outer loop
+      vertex 0 60 5
+      vertex 5 55 5
+      vertex 60 60 5
+    endloop
+  endfacet
+  facet normal -0 0 1
+    outer loop
+      vertex 55 5 5
+      vertex 60 0 5
+      vertex 55 55 5
+    endloop
+  endfacet
+  facet normal -0 0 1
+    outer loop
+      vertex 5 5 5
+      vertex 60 0 5
+      vertex 55 5 5
+    endloop
+  endfacet
+  facet normal 0 0 1
+    outer loop
+      vertex 5 5 5
+      vertex 0 0 5
+      vertex 60 0 5
+    endloop
+  endfacet
+  facet normal 0 0 1
+    outer loop
+      vertex 0 0 5
+      vertex 5 5 5
+      vertex 0 60 5
+    endloop
+  endfacet
+  facet normal 1 -0 0
+    outer loop
+      vertex 60 0 5
+      vertex 60 60 0
+      vertex 60 60 5
+    endloop
+  endfacet
+  facet normal 1 0 0
+    outer loop
+      vertex 60 60 0
+      vertex 60 0 5
+      vertex 60 0 0
+    endloop
+  endfacet
+  facet normal 0 1 -0
+    outer loop
+      vertex 60 60 0
+      vertex 0 60 5
+      vertex 60 60 5
+    endloop
+  endfacet
+  facet normal 0 1 0
+    outer loop
+      vertex 0 60 5
+      vertex 60 60 0
+      vertex 0 60 0
+    endloop
+  endfacet
+  facet normal 0 0 -1
+    outer loop
+      vertex 60 0 0
+      vertex 55 5 0
+      vertex 60 60 0
+    endloop
+  endfacet
+  facet normal 0 0 -1
+    outer loop
+      vertex 60 0 0
+      vertex 5 5 0
+      vertex 55 5 0
+    endloop
+  endfacet
+  facet normal -0 0 -1
+    outer loop
+      vertex 5 5 0
+      vertex 0 0 0
+      vertex 5 55 0
+    endloop
+  endfacet
+  facet normal 0 0 -1
+    outer loop
+      vertex 0 0 0
+      vertex 5 5 0
+      vertex 60 0 0
+    endloop
+  endfacet
+  facet normal 0 0 -1
+    outer loop
+      vertex 55 55 0
+      vertex 60 60 0
+      vertex 55 5 0
+    endloop
+  endfacet
+  facet normal 0 0 -1
+    outer loop
+      vertex 5 55 0
+      vertex 60 60 0
+      vertex 55 55 0
+    endloop
+  endfacet
+  facet normal 0 0 -1
+    outer loop
+      vertex 5 55 0
+      vertex 0 60 0
+      vertex 60 60 0
+    endloop
+  endfacet
+  facet normal 0 0 -1
+    outer loop
+      vertex 0 60 0
+      vertex 5 55 0
+      vertex 0 0 0
+    endloop
+  endfacet
+  facet normal 0 -1 0
+    outer loop
+      vertex 0 0 0
+      vertex 60 0 5
+      vertex 0 0 5
+    endloop
+  endfacet
+  facet normal 0 -1 -0
+    outer loop
+      vertex 60 0 5
+      vertex 0 0 0
+      vertex 60 0 0
+    endloop
+  endfacet
+  facet normal 1 -0 0
+    outer loop
+      vertex 5 5 5
+      vertex 5 55 0
+      vertex 5 55 5
+    endloop
+  endfacet
+  facet normal 1 0 0
+    outer loop
+      vertex 5 55 0
+      vertex 5 5 5
+      vertex 5 5 0
+    endloop
+  endfacet
+  facet normal -1 0 0
+    outer loop
+      vertex 55 5 0
+      vertex 55 55 5
+      vertex 55 55 0
+    endloop
+  endfacet
+  facet normal -1 -0 0
+    outer loop
+      vertex 55 55 5
+      vertex 55 5 0
+      vertex 55 5 5
+    endloop
+  endfacet
+  facet normal 0 1 -0
+    outer loop
+      vertex 55 5 0
+      vertex 5 5 5
+      vertex 55 5 5
+    endloop
+  endfacet
+  facet normal 0 1 0
+    outer loop
+      vertex 5 5 5
+      vertex 55 5 0
+      vertex 5 5 0
+    endloop
+  endfacet
+  facet normal 0 -1 0
+    outer loop
+      vertex 5 55 0
+      vertex 55 55 5
+      vertex 5 55 5
+    endloop
+  endfacet
+  facet normal 0 -1 -0
+    outer loop
+      vertex 55 55 5
+      vertex 5 55 0
+      vertex 55 55 0
+    endloop
+  endfacet
+endsolid OpenSCAD_Model

klippy/cartesian.py

@@ -13,21 +13,19 @@ class CartKinematics:
         self.steppers = [stepper.PrinterStepper(
             printer, config.getsection('stepper_' + n), n)
                          for n in ['x', 'y', 'z']]
-        self.max_z_velocity = config.getfloat('max_z_velocity', 9999999.9)
-        self.max_z_accel = config.getfloat('max_z_accel', 9999999.9)
+        self.max_z_velocity = config.getfloat(
+            'max_z_velocity', 9999999.9, above=0.)
+        self.max_z_accel = config.getfloat(
+            'max_z_accel', 9999999.9, above=0.)
         self.need_motor_enable = True
         self.limits = [(1.0, -1.0)] * 3
-    def set_max_jerk(self, max_xy_halt_velocity, max_accel):
+    def set_max_jerk(self, max_xy_halt_velocity, max_velocity, max_accel):
         self.steppers[0].set_max_jerk(max_xy_halt_velocity, max_accel)
         self.steppers[1].set_max_jerk(max_xy_halt_velocity, max_accel)
         self.steppers[2].set_max_jerk(0., self.max_z_accel)
-    def build_config(self):
-        for stepper in self.steppers:
-            stepper.build_config()
     def set_position(self, newpos):
         for i in StepList:
-            s = self.steppers[i]
-            s.mcu_stepper.set_position(int(newpos[i]*s.inv_step_dist + 0.5))
+            self.steppers[i].mcu_stepper.set_position(newpos[i])
     def home(self, homing_state):
         # Each axis is homed independently and in order
         for axis in homing_state.get_axes():
@@ -58,7 +56,7 @@ class CartKinematics:
             homing_state.home(
                 list(coord), homepos, [s], s.homing_speed/2.0, second_home=True)
             # Set final homed position
-            coord[axis] = s.position_endstop + s.get_homed_offset()*s.step_dist
+            coord[axis] = s.position_endstop + s.get_homed_offset()
             homing_state.set_homed_position(coord)
     def motor_off(self, move_time):
         self.limits = [(1.0, -1.0)] * 3
@@ -102,46 +100,33 @@ class CartKinematics:
     def move(self, move_time, move):
         if self.need_motor_enable:
             self._check_motor_enable(move_time, move)
-        inv_accel = 1. / move.accel
-        inv_cruise_v = 1. / move.cruise_v
         for i in StepList:
-            if not move.axes_d[i]:
+            axis_d = move.axes_d[i]
+            if not axis_d:
                 continue
             mcu_stepper = self.steppers[i].mcu_stepper
             mcu_time = mcu_stepper.print_to_mcu_time(move_time)
-            step_pos = mcu_stepper.commanded_position
-            inv_step_dist = self.steppers[i].inv_step_dist
-            step_offset = step_pos - move.start_pos[i] * inv_step_dist
-            steps = move.axes_d[i] * inv_step_dist
-            move_step_d = move.move_d / abs(steps)
+            start_pos = move.start_pos[i]
+            axis_r = abs(axis_d) / move.move_d
+            accel = move.accel * axis_r
+            cruise_v = move.cruise_v * axis_r
 
             # Acceleration steps
-            accel_multiplier = 2.0 * move_step_d * inv_accel
             if move.accel_r:
-                #t = sqrt(2*pos/accel + (start_v/accel)**2) - start_v/accel
-                accel_time_offset = move.start_v * inv_accel
-                accel_sqrt_offset = accel_time_offset**2
-                accel_steps = move.accel_r * steps
-                count = mcu_stepper.step_sqrt(
-                    mcu_time - accel_time_offset, accel_steps, step_offset
-                    , accel_sqrt_offset, accel_multiplier)
-                step_offset += count - accel_steps
+                accel_d = move.accel_r * axis_d
+                mcu_stepper.step_const(
+                    mcu_time, start_pos, accel_d, move.start_v * axis_r, accel)
+                start_pos += accel_d
                 mcu_time += move.accel_t
             # Cruising steps
             if move.cruise_r:
-                #t = pos/cruise_v
-                cruise_multiplier = move_step_d * inv_cruise_v
-                cruise_steps = move.cruise_r * steps
-                count = mcu_stepper.step_factor(
-                    mcu_time, cruise_steps, step_offset, cruise_multiplier)
-                step_offset += count - cruise_steps
+                cruise_d = move.cruise_r * axis_d
+                mcu_stepper.step_const(
+                    mcu_time, start_pos, cruise_d, cruise_v, 0.)
+                start_pos += cruise_d
                 mcu_time += move.cruise_t
             # Deceleration steps
             if move.decel_r:
-                #t = cruise_v/accel - sqrt((cruise_v/accel)**2 - 2*pos/accel)
-                decel_time_offset = move.cruise_v * inv_accel
-                decel_sqrt_offset = decel_time_offset**2
-                decel_steps = move.decel_r * steps
-                count = mcu_stepper.step_sqrt(
-                    mcu_time + decel_time_offset, decel_steps, step_offset
-                    , decel_sqrt_offset, -accel_multiplier)
+                decel_d = move.decel_r * axis_d
+                mcu_stepper.step_const(
+                    mcu_time, start_pos, decel_d, cruise_v, -accel)

klippy/chelper.py

@@ -1,12 +1,17 @@
 # Wrapper around C helper code
 #
-# Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import os, logging
 import cffi
 
-COMPILE_CMD = "gcc -Wall -g -O -shared -fPIC -o %s %s"
+
+######################################################################
+# c_helper.so compiling
+######################################################################
+
+COMPILE_CMD = "gcc -Wall -g -O2 -shared -fPIC -o %s %s"
 SOURCE_FILES = ['stepcompress.c', 'serialqueue.c', 'pyhelper.c']
 DEST_LIB = "c_helper.so"
 OTHER_FILES = ['list.h', 'serialqueue.h', 'pyhelper.h']
@@ -16,31 +21,22 @@ defs_stepcompress = """
         , uint32_t queue_step_msgid, uint32_t set_next_step_dir_msgid
         , uint32_t invert_sdir, uint32_t oid);
     void stepcompress_free(struct stepcompress *sc);
-    void stepcompress_push(struct stepcompress *sc, double step_clock
+    int stepcompress_reset(struct stepcompress *sc, uint64_t last_step_clock);
+    int stepcompress_set_homing(struct stepcompress *sc, uint64_t homing_clock);
+    int stepcompress_queue_msg(struct stepcompress *sc, uint32_t *data, int len);
+
+    int stepcompress_push(struct stepcompress *sc, double step_clock
         , int32_t sdir);
-    int32_t stepcompress_push_factor(struct stepcompress *sc
-        , double steps, double step_offset
-        , double clock_offset, double factor);
-    int32_t stepcompress_push_sqrt(struct stepcompress *sc
-        , double steps, double step_offset
-        , double clock_offset, double sqrt_offset, double factor);
-    int32_t stepcompress_push_delta_const(struct stepcompress *sc
-        , double clock_offset, double dist, double start_pos
-        , double inv_velocity, double step_dist, double height
-        , double closestxy_d, double closest_height2, double movez_r);
-    int32_t stepcompress_push_delta_accel(struct stepcompress *sc
-        , double clock_offset, double dist, double start_pos
-        , double accel_multiplier, double step_dist, double height
-        , double closestxy_d, double closest_height2, double movez_r);
-    void stepcompress_reset(struct stepcompress *sc, uint64_t last_step_clock);
-    void stepcompress_queue_msg(struct stepcompress *sc
-        , uint32_t *data, int len);
-    uint32_t stepcompress_get_errors(struct stepcompress *sc);
+    int32_t stepcompress_push_const(struct stepcompress *sc, double clock_offset
+        , double step_offset, double steps, double start_sv, double accel);
+    int32_t stepcompress_push_delta(struct stepcompress *sc
+        , double clock_offset, double move_sd, double start_sv, double accel
+        , double height, double startxy_sd, double arm_d, double movez_r);
 
     struct steppersync *steppersync_alloc(struct serialqueue *sq
         , struct stepcompress **sc_list, int sc_num, int move_num);
     void steppersync_free(struct steppersync *ss);
-    void steppersync_flush(struct steppersync *ss, uint64_t move_clock);
+    int steppersync_flush(struct steppersync *ss, uint64_t move_clock);
 """
 
 defs_serialqueue = """
@@ -65,7 +61,6 @@ defs_serialqueue = """
     void serialqueue_set_baud_adjust(struct serialqueue *sq, double baud_adjust);
     void serialqueue_set_clock_est(struct serialqueue *sq, double est_clock
         , double last_ack_time, uint64_t last_ack_clock);
-    void serialqueue_flush_ready(struct serialqueue *sq);
     void serialqueue_get_stats(struct serialqueue *sq, char *buf, int len);
     int serialqueue_extract_old(struct serialqueue *sq, int sentq
         , struct pull_queue_message *q, int max);
@@ -73,6 +68,7 @@ defs_serialqueue = """
 
 defs_pyhelper = """
     void set_python_logging_callback(void (*func)(const char *));
+    double get_monotonic(void);
 """
 
 # Return the list of file modification times
@@ -88,14 +84,14 @@ def get_mtimes(srcdir, filelist):
     return out
 
 # Check if the code needs to be compiled
-def check_build_code(srcdir):
-    src_times = get_mtimes(srcdir, SOURCE_FILES + OTHER_FILES)
-    obj_times = get_mtimes(srcdir, [DEST_LIB])
+def check_build_code(srcdir, target, sources, cmd, other_files=[]):
+    src_times = get_mtimes(srcdir, sources + other_files)
+    obj_times = get_mtimes(srcdir, [target])
     if not obj_times or max(src_times) > min(obj_times):
-        logging.info("Building C code module")
-        srcfiles = [os.path.join(srcdir, fname) for fname in SOURCE_FILES]
-        destlib = os.path.join(srcdir, DEST_LIB)
-        os.system(COMPILE_CMD % (destlib, ' '.join(srcfiles)))
+        logging.info("Building C code module %s" % (target,))
+        srcfiles = [os.path.join(srcdir, fname) for fname in sources]
+        destlib = os.path.join(srcdir, target)
+        os.system(cmd % (destlib, ' '.join(srcfiles)))
 
 FFI_main = None
 FFI_lib = None
@@ -106,7 +102,8 @@ def get_ffi():
     global FFI_main, FFI_lib, pyhelper_logging_callback
     if FFI_lib is None:
         srcdir = os.path.dirname(os.path.realpath(__file__))
-        check_build_code(srcdir)
+        check_build_code(srcdir, DEST_LIB, SOURCE_FILES, COMPILE_CMD
+                         , OTHER_FILES)
         FFI_main = cffi.FFI()
         FFI_main.cdef(defs_stepcompress)
         FFI_main.cdef(defs_serialqueue)
@@ -119,3 +116,20 @@ def get_ffi():
             "void(const char *)", logging_callback)
         FFI_lib.set_python_logging_callback(pyhelper_logging_callback)
     return FFI_main, FFI_lib
+
+
+######################################################################
+# hub-ctrl hub power controller
+######################################################################
+
+HC_COMPILE_CMD = "gcc -Wall -g -O2 -o %s %s -lusb"
+HC_SOURCE_FILES = ['hub-ctrl.c']
+HC_SOURCE_DIR = '../lib/hub-ctrl'
+HC_TARGET = "hub-ctrl"
+HC_CMD = "sudo %s/hub-ctrl -h 0 -P 2 -p %d"
+
+def run_hub_ctrl(enable_power):
+    srcdir = os.path.dirname(os.path.realpath(__file__))
+    hubdir = os.path.join(srcdir, HC_SOURCE_DIR)
+    check_build_code(hubdir, HC_TARGET, HC_SOURCE_FILES, HC_COMPILE_CMD)
+    os.system(HC_CMD % (hubdir, enable_power))

klippy/console.py

@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 # Script to implement a test console with firmware over serial port
 #
-# Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import sys, optparse, os, re, logging
@@ -16,6 +16,7 @@ class KeyboardReader:
         self.reactor = reactor
         self.fd = sys.stdin.fileno()
         util.set_nonblock(self.fd)
+        self.mcu_freq = 0
         self.pins = None
         self.data = ""
         reactor.register_fd(self.fd, self.process_kbd)
@@ -24,49 +25,51 @@ class KeyboardReader:
         self.eval_globals = {}
     def connect(self, eventtime):
         self.ser.connect()
+        self.ser.handle_default = self.handle_default
+        self.mcu_freq = self.ser.msgparser.get_constant_float('CLOCK_FREQ')
+        mcu = self.ser.msgparser.get_constant('MCU')
+        self.pins = pins.get_pin_map(mcu)
         self.reactor.unregister_timer(self.connect_timer)
         return self.reactor.NEVER
+    def output(self, msg):
+        sys.stdout.write("%s\n" % (msg,))
+        sys.stdout.flush()
+    def handle_default(self, params):
+        self.output(self.ser.msgparser.format_params(params))
     def update_evals(self, eventtime):
-        f = int(self.ser.msgparser.config.get('CLOCK_FREQ', 1))
-        c = self.ser.get_clock(eventtime)
-        self.eval_globals['freq'] = f
-        self.eval_globals['clock'] = int(c)
+        self.eval_globals['freq'] = self.mcu_freq
+        self.eval_globals['clock'] = self.ser.get_clock(eventtime)
     def set_pin_map(self, parts):
-        mcu = self.ser.msgparser.config['MCU']
-        self.pins = pins.map_pins(parts[1], mcu)
+        mcu = self.ser.msgparser.get_constant('MCU')
+        self.pins = pins.get_pin_map(mcu, parts[1])
     def set_var(self, parts):
         val = parts[2]
-        try:
-            val = int(val)
-        except ValueError:
         try:
             val = float(val)
         except ValueError:
             pass
         self.eval_globals[parts[1]] = val
-    def lookup_pin(self, value):
-        if self.pins is None:
-            self.pins = pins.mcu_to_pins(self.ser.msgparser.config['MCU'])
-        return self.pins[value]
     def translate(self, line, eventtime):
         evalparts = re_eval.split(line)
         if len(evalparts) > 1:
             self.update_evals(eventtime)
             try:
                 for i in range(1, len(evalparts), 2):
-                    evalparts[i] = str(eval(evalparts[i], self.eval_globals))
+                    e = eval(evalparts[i], self.eval_globals)
+                    if type(e) == type(0.):
+                        e = int(e)
+                    evalparts[i] = str(e)
             except:
-                print "Unable to evaluate: ", line
+                self.output("Unable to evaluate: %s" % (line,))
                 return None
             line = ''.join(evalparts)
-            print "Eval:", line
-        if self.pins is None and self.ser.msgparser.config:
-            self.pins = pins.mcu_to_pins(self.ser.msgparser.config['MCU'])
+            self.output("Eval: %s" % (line,))
         if self.pins is not None:
             try:
-                line = pins.update_command(line, self.pins).strip()
+                line = pins.update_command(
+                    line, self.mcu_freq, self.pins).strip()
             except:
-                print "Unable to map pin: ", line
+                self.output("Unable to map pin: %s" % (line,))
                 return None
         if line:
             parts = line.split()
@@ -76,7 +79,7 @@ class KeyboardReader:
         try:
             msg = self.ser.msgparser.create_command(line)
         except msgproto.error, e:
-            print "Error:", e
+            self.output("Error: %s" % (str(e),))
             return None
         return msg
     def process_kbd(self, eventtime):

klippy/corexy.py

@@ -0,0 +1,146 @@
+# Code for handling the kinematics of corexy robots
+#
+# Copyright (C) 2017  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import logging
+import stepper, homing
+
+StepList = (0, 1, 2)
+
+class CoreXYKinematics:
+    def __init__(self, printer, config):
+        self.steppers = [stepper.PrinterStepper(
+            printer, config.getsection('stepper_' + n), n)
+                         for n in ['x', 'y', 'z']]
+        self.steppers[0].mcu_endstop.add_stepper(self.steppers[1].mcu_stepper)
+        self.steppers[1].mcu_endstop.add_stepper(self.steppers[0].mcu_stepper)
+        self.max_z_velocity = config.getfloat(
+            'max_z_velocity', 9999999.9, above=0.)
+        self.max_z_accel = config.getfloat(
+            'max_z_accel', 9999999.9, above=0.)
+        self.need_motor_enable = True
+        self.limits = [(1.0, -1.0)] * 3
+    def set_max_jerk(self, max_xy_halt_velocity, max_velocity, max_accel):
+        self.steppers[0].set_max_jerk(max_xy_halt_velocity, max_accel)
+        self.steppers[1].set_max_jerk(max_xy_halt_velocity, max_accel)
+        self.steppers[2].set_max_jerk(0., self.max_z_accel)
+    def set_position(self, newpos):
+        pos = (newpos[0] + newpos[1], newpos[0] - newpos[1], newpos[2])
+        for i in StepList:
+            self.steppers[i].mcu_stepper.set_position(pos[i])
+    def home(self, homing_state):
+        # Each axis is homed independently and in order
+        for axis in homing_state.get_axes():
+            s = self.steppers[axis]
+            self.limits[axis] = (s.position_min, s.position_max)
+            # Determine moves
+            if s.homing_positive_dir:
+                pos = s.position_endstop - 1.5*(
+                    s.position_endstop - s.position_min)
+                rpos = s.position_endstop - s.homing_retract_dist
+                r2pos = rpos - s.homing_retract_dist
+            else:
+                pos = s.position_endstop + 1.5*(
+                    s.position_max - s.position_endstop)
+                rpos = s.position_endstop + s.homing_retract_dist
+                r2pos = rpos + s.homing_retract_dist
+            # Initial homing
+            homepos = [None, None, None, None]
+            homepos[axis] = s.position_endstop
+            coord = [None, None, None, None]
+            coord[axis] = pos
+            homing_state.home(list(coord), homepos, [s], s.homing_speed)
+            # Retract
+            coord[axis] = rpos
+            homing_state.retract(list(coord), s.homing_speed)
+            # Home again
+            coord[axis] = r2pos
+            homing_state.home(
+                list(coord), homepos, [s], s.homing_speed/2.0, second_home=True)
+            if axis == 2:
+                # Support endstop phase detection on Z axis
+                coord[axis] = s.position_endstop + s.get_homed_offset()
+                homing_state.set_homed_position(coord)
+    def motor_off(self, move_time):
+        self.limits = [(1.0, -1.0)] * 3
+        for stepper in self.steppers:
+            stepper.motor_enable(move_time, 0)
+        self.need_motor_enable = True
+    def _check_motor_enable(self, move_time, move):
+        if move.axes_d[0] or move.axes_d[1]:
+            self.steppers[0].motor_enable(move_time, 1)
+            self.steppers[1].motor_enable(move_time, 1)
+        if move.axes_d[2]:
+            self.steppers[2].motor_enable(move_time, 1)
+        need_motor_enable = False
+        for i in StepList:
+            need_motor_enable |= self.steppers[i].need_motor_enable
+        self.need_motor_enable = need_motor_enable
+    def query_endstops(self, print_time):
+        endstops = [(s, s.query_endstop(print_time)) for s in self.steppers]
+        return [(s.name, es.query_endstop_wait()) for s, es in endstops]
+    def _check_endstops(self, move):
+        end_pos = move.end_pos
+        for i in StepList:
+            if (move.axes_d[i]
+                and (end_pos[i] < self.limits[i][0]
+                     or end_pos[i] > self.limits[i][1])):
+                if self.limits[i][0] > self.limits[i][1]:
+                    raise homing.EndstopMoveError(
+                        end_pos, "Must home axis first")
+                raise homing.EndstopMoveError(end_pos)
+    def check_move(self, move):
+        limits = self.limits
+        xpos, ypos = move.end_pos[:2]
+        if (xpos < limits[0][0] or xpos > limits[0][1]
+            or ypos < limits[1][0] or ypos > limits[1][1]):
+            self._check_endstops(move)
+        if not move.axes_d[2]:
+            # Normal XY move - use defaults
+            return
+        # Move with Z - update velocity and accel for slower Z axis
+        self._check_endstops(move)
+        z_ratio = move.move_d / abs(move.axes_d[2])
+        move.limit_speed(
+            self.max_z_velocity * z_ratio, self.max_z_accel * z_ratio)
+    def move(self, move_time, move):
+        if self.need_motor_enable:
+            self._check_motor_enable(move_time, move)
+        sxp = move.start_pos[0]
+        syp = move.start_pos[1]
+        move_start_pos = (sxp + syp, sxp - syp, move.start_pos[2])
+        exp = move.end_pos[0]
+        eyp = move.end_pos[1]
+        axes_d = ((exp + eyp) - move_start_pos[0],
+                  (exp - eyp) - move_start_pos[1], move.axes_d[2])
+        for i in StepList:
+            axis_d = axes_d[i]
+            if not axis_d:
+                continue
+            mcu_stepper = self.steppers[i].mcu_stepper
+            mcu_time = mcu_stepper.print_to_mcu_time(move_time)
+            start_pos = move_start_pos[i]
+            axis_r = abs(axis_d) / move.move_d
+            accel = move.accel * axis_r
+            cruise_v = move.cruise_v * axis_r
+
+            # Acceleration steps
+            if move.accel_r:
+                accel_d = move.accel_r * axis_d
+                mcu_stepper.step_const(
+                    mcu_time, start_pos, accel_d, move.start_v * axis_r, accel)
+                start_pos += accel_d
+                mcu_time += move.accel_t
+            # Cruising steps
+            if move.cruise_r:
+                cruise_d = move.cruise_r * axis_d
+                mcu_stepper.step_const(
+                    mcu_time, start_pos, cruise_d, cruise_v, 0.)
+                start_pos += cruise_d
+                mcu_time += move.cruise_t
+            # Deceleration steps
+            if move.decel_r:
+                decel_d = move.decel_r * axis_d
+                mcu_stepper.step_const(
+                    mcu_time, start_pos, decel_d, cruise_v, -accel)

klippy/delta.py

@@ -1,6 +1,6 @@
 # Code for handling the kinematics of linear delta robots
 #
-# Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import math, logging
@@ -8,40 +8,61 @@ import stepper, homing
 
 StepList = (0, 1, 2)
 
+# Slow moves once the ratio of tower to XY movement exceeds SLOW_RATIO
+SLOW_RATIO = 3.
+
 class DeltaKinematics:
     def __init__(self, printer, config):
+        self.config = config
         self.steppers = [stepper.PrinterStepper(
             printer, config.getsection('stepper_' + n), n)
                          for n in ['a', 'b', 'c']]
-        self.need_motor_enable = True
-        self.max_z_velocity = config.getfloat('max_z_velocity', 9999999.9)
-        radius = config.getfloat('delta_radius')
-        arm_length = config.getfloat('delta_arm_length')
+        self.need_motor_enable = self.need_home = True
+        self.max_velocity = self.max_z_velocity = self.max_accel = 0.
+        radius = config.getfloat('delta_radius', above=0.)
+        arm_length = config.getfloat('delta_arm_length', above=radius)
         self.arm_length2 = arm_length**2
-        self.max_xy2 = min(radius, arm_length - radius)**2
         self.limit_xy2 = -1.
         tower_height_at_zeros = math.sqrt(self.arm_length2 - radius**2)
-        self.max_z = self.steppers[0].position_max
+        self.max_z = max([s.position_endstop for s in self.steppers])
         self.limit_z = self.max_z - (arm_length - tower_height_at_zeros)
+        logging.info(
+            "Delta max build height %.2fmm (radius tapered above %.2fmm)" % (
+                self.max_z, self.limit_z))
         sin = lambda angle: math.sin(math.radians(angle))
         cos = lambda angle: math.cos(math.radians(angle))
         self.towers = [
             (cos(210.)*radius, sin(210.)*radius),
             (cos(330.)*radius, sin(330.)*radius),
             (cos(90.)*radius, sin(90.)*radius)]
-    def set_max_jerk(self, max_xy_halt_velocity, max_accel):
-        # XXX - this sets conservative values
+        # Find the point where an XY move could result in excessive
+        # tower movement
+        half_min_step_dist = min([s.step_dist for s in self.steppers]) * .5
+        def ratio_to_dist(ratio):
+            return (ratio * math.sqrt(self.arm_length2 / (ratio**2 + 1.)
+                                      - half_min_step_dist**2)
+                    + half_min_step_dist)
+        self.slow_xy2 = (ratio_to_dist(SLOW_RATIO) - radius)**2
+        self.very_slow_xy2 = (ratio_to_dist(2. * SLOW_RATIO) - radius)**2
+        self.max_xy2 = min(radius, arm_length - radius,
+                           ratio_to_dist(4. * SLOW_RATIO) - radius)**2
+        logging.info(
+            "Delta max build radius %.2fmm (moves slowed past %.2fmm and %.2fmm)"
+            % (math.sqrt(self.max_xy2), math.sqrt(self.slow_xy2),
+               math.sqrt(self.very_slow_xy2)))
+        self.set_position([0., 0., 0.])
+    def set_max_jerk(self, max_xy_halt_velocity, max_velocity, max_accel):
+        self.max_velocity = max_velocity
+        max_z_velocity = self.config.getfloat(
+            'max_z_velocity', max_velocity, above=0.)
+        self.max_z_velocity = min(max_velocity, max_z_velocity)
+        self.max_accel = max_accel
         for stepper in self.steppers:
             stepper.set_max_jerk(max_xy_halt_velocity, max_accel)
-    def build_config(self):
-        for stepper in self.steppers:
-            stepper.build_config()
-        self.set_position([0., 0., 0.])
     def _cartesian_to_actuator(self, coord):
-        return [int((math.sqrt(self.arm_length2
+        return [math.sqrt(self.arm_length2
                           - (self.towers[i][0] - coord[0])**2
-                               - (self.towers[i][1] - coord[1])**2) + coord[2])
-                    * self.steppers[i].inv_step_dist + 0.5)
+                          - (self.towers[i][1] - coord[1])**2) + coord[2]
                 for i in StepList]
     def _actuator_to_cartesian(self, pos):
         # Based on code from Smoothieware
@@ -78,13 +99,14 @@ class DeltaKinematics:
         pos = self._cartesian_to_actuator(newpos)
         for i in StepList:
             self.steppers[i].mcu_stepper.set_position(pos[i])
+        self.limit_xy2 = -1.
     def home(self, homing_state):
         # All axes are homed simultaneously
         homing_state.set_axes([0, 1, 2])
-        s = self.steppers[0] # Assume homing parameters same for all steppers
-        self.limit_xy2 = self.max_xy2
+        s = self.steppers[0] # Assume homing speed same for all steppers
+        self.need_home = False
         # Initial homing
-        homepos = [0., 0., s.position_endstop, None]
+        homepos = [0., 0., self.max_z, None]
         coord = list(homepos)
         coord[2] = -1.5 * math.sqrt(self.arm_length2-self.max_xy2)
         homing_state.home(list(coord), homepos, self.steppers, s.homing_speed)
@@ -96,15 +118,14 @@ class DeltaKinematics:
         homing_state.home(list(coord), homepos, self.steppers
                           , s.homing_speed/2.0, second_home=True)
         # Set final homed position
-        coord = [(s.mcu_stepper.commanded_position + s.get_homed_offset())
-                 * s.step_dist
+        coord = [s.mcu_stepper.get_commanded_position() + s.get_homed_offset()
                  for s in self.steppers]
         homing_state.set_homed_position(self._actuator_to_cartesian(coord))
     def motor_off(self, move_time):
         self.limit_xy2 = -1.
         for stepper in self.steppers:
             stepper.motor_enable(move_time, 0)
-        self.need_motor_enable = True
+        self.need_motor_enable = self.need_home = True
     def _check_motor_enable(self, move_time):
         for i in StepList:
             self.steppers[i].motor_enable(move_time, 1)
@@ -115,127 +136,90 @@ class DeltaKinematics:
     def check_move(self, move):
         end_pos = move.end_pos
         xy2 = end_pos[0]**2 + end_pos[1]**2
-        if xy2 > self.limit_xy2 or end_pos[2] < 0.:
-            if self.limit_xy2 < 0.:
+        if xy2 <= self.limit_xy2 and not move.axes_d[2]:
+            # Normal XY move
+            return
+        if self.need_home:
             raise homing.EndstopMoveError(end_pos, "Must home first")
-            raise homing.EndstopMoveError(end_pos)
+        limit_xy2 = self.max_xy2
         if end_pos[2] > self.limit_z:
-            if end_pos[2] > self.max_z or xy2 > (self.max_z - end_pos[2])**2:
+            limit_xy2 = min(limit_xy2, (self.max_z - end_pos[2])**2)
+        if xy2 > limit_xy2 or end_pos[2] < 0. or end_pos[2] > self.max_z:
             raise homing.EndstopMoveError(end_pos)
         if move.axes_d[2]:
-            move.limit_speed(self.max_z_velocity, 9999999.9)
+            move.limit_speed(self.max_z_velocity, move.accel)
+            limit_xy2 = -1.
+        # Limit the speed/accel of this move if is is at the extreme
+        # end of the build envelope
+        extreme_xy2 = max(xy2, move.start_pos[0]**2 + move.start_pos[1]**2)
+        if extreme_xy2 > self.slow_xy2:
+            r = 0.5
+            if extreme_xy2 > self.very_slow_xy2:
+                r = 0.25
+            max_velocity = self.max_velocity
+            if move.axes_d[2]:
+                max_velocity = self.max_z_velocity
+            move.limit_speed(max_velocity * r, self.max_accel * r)
+            limit_xy2 = -1.
+        self.limit_xy2 = min(limit_xy2, self.slow_xy2)
     def move(self, move_time, move):
+        if self.need_motor_enable:
+            self._check_motor_enable(move_time)
         axes_d = move.axes_d
-        move_d = movexy_d = move.move_d
+        move_d = move.move_d
         movexy_r = 1.
         movez_r = 0.
-        inv_movexy_d = 1. / movexy_d
+        inv_movexy_d = 1. / move_d
         if not axes_d[0] and not axes_d[1]:
-            if not axes_d[2]:
-                return
+            # Z only move
             movez_r = axes_d[2] * inv_movexy_d
-            movexy_d = movexy_r = inv_movexy_d = 0.
+            movexy_r = inv_movexy_d = 0.
         elif axes_d[2]:
+            # XY+Z move
             movexy_d = math.sqrt(axes_d[0]**2 + axes_d[1]**2)
             movexy_r = movexy_d * inv_movexy_d
             movez_r = axes_d[2] * inv_movexy_d
             inv_movexy_d = 1. / movexy_d
 
-        if self.need_motor_enable:
-            self._check_motor_enable(move_time)
-
         origx, origy, origz = move.start_pos[:3]
 
-        accel_t = move.accel_t
-        cruise_end_t = accel_t + move.cruise_t
+        accel = move.accel
+        cruise_v = move.cruise_v
         accel_d = move.accel_r * move_d
-        cruise_end_d = accel_d + move.cruise_r * move_d
-
-        inv_cruise_v = 1. / move.cruise_v
-        inv_accel = 1. / move.accel
-        accel_time_offset = move.start_v * inv_accel
-        accel_multiplier = 2.0 * inv_accel
-        accel_offset = move.start_v**2 * 0.5 * inv_accel
-        decel_time_offset = move.cruise_v * inv_accel + cruise_end_t
-        decel_offset = move.cruise_v**2 * 0.5 * inv_accel + cruise_end_d
+        cruise_d = move.cruise_r * move_d
+        decel_d = move.decel_r * move_d
 
         for i in StepList:
-            # Find point on line of movement closest to tower
+            # Calculate a virtual tower along the line of movement at
+            # the point closest to this stepper's tower.
             towerx_d = self.towers[i][0] - origx
             towery_d = self.towers[i][1] - origy
-            closestxy_d = (towerx_d*axes_d[0] + towery_d*axes_d[1])*inv_movexy_d
-            tangentxy_d2 = towerx_d**2 + towery_d**2 - closestxy_d**2
-            closest_height2 = self.arm_length2 - tangentxy_d2
-
-            # Calculate accel/cruise/decel portions of move
-            reversexy_d = closestxy_d + math.sqrt(closest_height2)*movez_r
-            accel_up_d = cruise_up_d = decel_up_d = 0.
-            accel_down_d = cruise_down_d = decel_down_d = 0.
-            if reversexy_d <= 0.:
-                accel_down_d = accel_d
-                cruise_down_d = cruise_end_d
-                decel_down_d = move_d
-            elif reversexy_d >= movexy_d:
-                accel_up_d = accel_d
-                cruise_up_d = cruise_end_d
-                decel_up_d = move_d
-            elif reversexy_d < accel_d * movexy_r:
-                accel_up_d = reversexy_d * move_d * inv_movexy_d
-                accel_down_d = accel_d
-                cruise_down_d = cruise_end_d
-                decel_down_d = move_d
-            elif reversexy_d < cruise_end_d * movexy_r:
-                accel_up_d = accel_d
-                cruise_up_d = reversexy_d * move_d * inv_movexy_d
-                cruise_down_d = cruise_end_d
-                decel_down_d = move_d
-            else:
-                accel_up_d = accel_d
-                cruise_up_d = cruise_end_d
-                decel_up_d = reversexy_d * move_d * inv_movexy_d
-                decel_down_d = move_d
+            vt_startxy_d = (towerx_d*axes_d[0] + towery_d*axes_d[1])*inv_movexy_d
+            tangentxy_d2 = towerx_d**2 + towery_d**2 - vt_startxy_d**2
+            vt_arm_d = math.sqrt(self.arm_length2 - tangentxy_d2)
+            vt_startz = origz
 
             # Generate steps
             mcu_stepper = self.steppers[i].mcu_stepper
             mcu_time = mcu_stepper.print_to_mcu_time(move_time)
-            step_pos = mcu_stepper.commanded_position
-            step_dist = self.steppers[i].step_dist
-            height = step_pos*step_dist - origz
-            if accel_up_d > 0.:
-                count = mcu_stepper.step_delta_accel(
-                    mcu_time - accel_time_offset, accel_up_d,
-                    accel_offset, accel_multiplier, step_dist,
-                    height, closestxy_d, closest_height2, movez_r)
-                height += count * step_dist
-            if cruise_up_d > 0.:
-                count = mcu_stepper.step_delta_const(
-                    mcu_time + accel_t, cruise_up_d,
-                    -accel_d, inv_cruise_v, step_dist,
-                    height, closestxy_d, closest_height2, movez_r)
-                height += count * step_dist
-            if decel_up_d > 0.:
-                count = mcu_stepper.step_delta_accel(
-                    mcu_time + decel_time_offset, decel_up_d,
-                    -decel_offset, -accel_multiplier, step_dist,
-                    height, closestxy_d, closest_height2, movez_r)
-                height += count * step_dist
-            if accel_down_d > 0.:
-                count = mcu_stepper.step_delta_accel(
-                    mcu_time - accel_time_offset, accel_down_d,
-                    accel_offset, accel_multiplier, -step_dist,
-                    height, closestxy_d, closest_height2, movez_r)
-                height += count * step_dist
-            if cruise_down_d > 0.:
-                count = mcu_stepper.step_delta_const(
-                    mcu_time + accel_t, cruise_down_d,
-                    -accel_d, inv_cruise_v, -step_dist,
-                    height, closestxy_d, closest_height2, movez_r)
-                height += count * step_dist
-            if decel_down_d > 0.:
-                count = mcu_stepper.step_delta_accel(
-                    mcu_time + decel_time_offset, decel_down_d,
-                    -decel_offset, -accel_multiplier, -step_dist,
-                    height, closestxy_d, closest_height2, movez_r)
+            if accel_d:
+                mcu_stepper.step_delta(
+                    mcu_time, accel_d, move.start_v, accel,
+                    vt_startz, vt_startxy_d, vt_arm_d, movez_r)
+                vt_startz += accel_d * movez_r
+                vt_startxy_d -= accel_d * movexy_r
+                mcu_time += move.accel_t
+            if cruise_d:
+                mcu_stepper.step_delta(
+                    mcu_time, cruise_d, cruise_v, 0.,
+                    vt_startz, vt_startxy_d, vt_arm_d, movez_r)
+                vt_startz += cruise_d * movez_r
+                vt_startxy_d -= cruise_d * movexy_r
+                mcu_time += move.cruise_t
+            if decel_d:
+                mcu_stepper.step_delta(
+                    mcu_time, decel_d, cruise_v, -accel,
+                    vt_startz, vt_startxy_d, vt_arm_d, movez_r)
 
 
 ######################################################################

klippy/extruder.py

@@ -3,45 +3,127 @@
 # Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import logging
+import math, logging
 import stepper, heater, homing
 
+EXTRUDE_DIFF_IGNORE = 1.02
+
 class PrinterExtruder:
     def __init__(self, printer, config):
+        self.config = config
         self.heater = heater.PrinterHeater(printer, config)
         self.stepper = stepper.PrinterStepper(printer, config, 'extruder')
-        self.pressure_advance = config.getfloat('pressure_advance', 0.)
-        self.max_e_velocity = config.getfloat('max_velocity')
-        self.max_e_accel = config.getfloat('max_accel')
+        self.nozzle_diameter = config.getfloat('nozzle_diameter', above=0.)
+        filament_diameter = config.getfloat(
+            'filament_diameter', minval=self.nozzle_diameter)
+        filament_area = math.pi * (filament_diameter * .5)**2
+        max_cross_section = config.getfloat(
+            'max_extrude_cross_section', 4. * self.nozzle_diameter**2
+            , above=0.)
+        self.max_extrude_ratio = max_cross_section / filament_area
+        self.max_e_dist = config.getfloat(
+            'max_extrude_only_distance', 50., minval=0.)
+        self.max_e_velocity = self.max_e_accel = None
+        self.pressure_advance = config.getfloat(
+            'pressure_advance', 0., minval=0.)
+        self.pressure_advance_lookahead_time = 0.
+        if self.pressure_advance:
+            self.pressure_advance_lookahead_time = config.getfloat(
+                'pressure_advance_lookahead_time', 0.010, minval=0.)
         self.need_motor_enable = True
         self.extrude_pos = 0.
-    def build_config(self):
-        self.heater.build_config()
+    def set_max_jerk(self, max_xy_halt_velocity, max_velocity, max_accel):
+        self.max_e_velocity = self.config.getfloat(
+            'max_extrude_only_velocity', max_velocity * self.max_extrude_ratio
+            , above=0.)
+        self.max_e_accel = self.config.getfloat(
+            'max_extrude_only_accel', max_accel * self.max_extrude_ratio
+            , above=0.)
         self.stepper.set_max_jerk(9999999.9, 9999999.9)
-        self.stepper.build_config()
     def motor_off(self, move_time):
         self.stepper.motor_enable(move_time, 0)
         self.need_motor_enable = True
     def check_move(self, move):
+        move.extrude_r = move.axes_d[3] / move.move_d
+        move.extrude_max_corner_v = 0.
         if not self.heater.can_extrude:
             raise homing.EndstopMoveError(
                 move.end_pos, "Extrude below minimum temp")
-        if (not move.do_calc_junction
-            and not move.axes_d[0] and not move.axes_d[1]
-            and not move.axes_d[2]):
-            # Extrude only move - limit accel and velocity
-            move.limit_speed(self.max_e_velocity, self.max_e_accel)
+        if not move.is_kinematic_move or move.extrude_r < 0.:
+            # Extrude only move (or retraction move) - limit accel and velocity
+            if abs(move.axes_d[3]) > self.max_e_dist:
+                raise homing.EndstopMoveError(
+                    move.end_pos, "Extrude move too long")
+            inv_extrude_r = 1. / abs(move.extrude_r)
+            move.limit_speed(self.max_e_velocity * inv_extrude_r
+                             , self.max_e_accel * inv_extrude_r)
+        elif (move.extrude_r > self.max_extrude_ratio
+              and move.axes_d[3] > self.nozzle_diameter*self.max_extrude_ratio):
+            logging.debug("Overextrude: %s vs %s" % (
+                move.extrude_r, self.max_extrude_ratio))
+            raise homing.EndstopMoveError(
+                move.end_pos, "Move exceeds maximum extrusion cross section")
+    def calc_junction(self, prev_move, move):
+        extrude = move.axes_d[3]
+        prev_extrude = prev_move.axes_d[3]
+        if extrude or prev_extrude:
+            if not extrude or not prev_extrude:
+                # Extrude move to non-extrude move - disable lookahead
+                return 0.
+            if ((move.extrude_r > prev_move.extrude_r * EXTRUDE_DIFF_IGNORE
+                 or prev_move.extrude_r > move.extrude_r * EXTRUDE_DIFF_IGNORE)
+                and abs(move.move_d * prev_move.extrude_r - extrude) >= .001):
+                # Extrude ratio between moves is too different
+                return 0.
+            move.extrude_r = prev_move.extrude_r
+        return move.max_cruise_v2
+    def lookahead(self, moves, flush_count, lazy):
+        lookahead_t = self.pressure_advance_lookahead_time
+        if not lookahead_t:
+            return flush_count
+        # Calculate max_corner_v - the speed the head will accelerate
+        # to after cornering.
+        for i in range(flush_count):
+            move = moves[i]
+            if not move.decel_t:
+                continue
+            cruise_v = move.cruise_v
+            max_corner_v = 0.
+            sum_t = lookahead_t
+            for j in range(i+1, flush_count):
+                fmove = moves[j]
+                if not fmove.max_start_v2:
+                    break
+                if fmove.cruise_v > max_corner_v:
+                    if (not max_corner_v
+                        and not fmove.accel_t and not fmove.cruise_t):
+                        # Start timing after any full decel moves
+                        continue
+                    if sum_t >= fmove.accel_t:
+                        max_corner_v = fmove.cruise_v
+                    else:
+                        max_corner_v = max(
+                            max_corner_v, fmove.start_v + fmove.accel * sum_t)
+                    if max_corner_v >= cruise_v:
+                        break
+                sum_t -= fmove.accel_t + fmove.cruise_t + fmove.decel_t
+                if sum_t <= 0.:
+                    break
+            else:
+                if lazy:
+                    return i
+            move.extrude_max_corner_v = max_corner_v
+        return flush_count
     def move(self, move_time, move):
         if self.need_motor_enable:
             self.stepper.motor_enable(move_time, 1)
             self.need_motor_enable = False
         axis_d = move.axes_d[3]
-        extrude_r = abs(axis_d) / move.move_d
-        inv_accel = 1. / (move.accel * extrude_r)
-
-        start_v = move.start_v * extrude_r
-        cruise_v = move.cruise_v * extrude_r
-        end_v = move.end_v * extrude_r
+        axis_r = abs(axis_d) / move.move_d
+        accel = move.accel * axis_r
+        start_v = move.start_v * axis_r
+        cruise_v = move.cruise_v * axis_r
+        end_v = move.end_v * axis_r
         accel_t, cruise_t, decel_t = move.accel_t, move.cruise_t, move.decel_t
         accel_d = move.accel_r * axis_d
         cruise_d = move.cruise_r * axis_d
@@ -55,25 +137,19 @@ class PrinterExtruder:
         if (axis_d >= 0. and (move.axes_d[0] or move.axes_d[1])
             and self.pressure_advance):
             # Increase accel_d and start_v when accelerating
-            move_extrude_r = move.extrude_r
+            pressure_advance = self.pressure_advance * move.extrude_r
             prev_pressure_d = start_pos - move.start_pos[3]
-            if accel_t:
-                npd = move.cruise_v * move_extrude_r * self.pressure_advance
+            if accel_d:
+                npd = move.cruise_v * pressure_advance
                 extra_accel_d = npd - prev_pressure_d
                 if extra_accel_d > 0.:
                     accel_d += extra_accel_d
                     start_v += extra_accel_d / accel_t
                     prev_pressure_d += extra_accel_d
             # Update decel and retract parameters when decelerating
-            if decel_t:
-                if move.corner_min:
-                    npd = move.corner_max*move_extrude_r * self.pressure_advance
-                    extra_decel_d = prev_pressure_d - npd
-                    if move.end_v > move.corner_min:
-                        extra_decel_d *= ((move.cruise_v - move.end_v)
-                                          / (move.cruise_v - move.corner_min))
-                else:
-                    npd = move.end_v * move_extrude_r * self.pressure_advance
+            emcv = move.extrude_max_corner_v
+            if decel_d and emcv < move.cruise_v:
+                npd = max(emcv, move.end_v) * pressure_advance
                 extra_decel_d = prev_pressure_d - npd
                 if extra_decel_d > 0.:
                     extra_decel_v = extra_decel_d / decel_t
@@ -87,7 +163,7 @@ class PrinterExtruder:
                         decel_t = decel_d = 0.
                     elif end_v < 0.:
                         # Split decel phase into decel and retraction
-                        retract_t = -end_v * inv_accel
+                        retract_t = -end_v / accel
                         retract_d = -end_v * 0.5 * retract_t
                         decel_t -= retract_t
                         decel_d = decel_v * 0.5 * decel_t
@@ -96,53 +172,41 @@ class PrinterExtruder:
                         decel_d -= extra_decel_d
 
         # Prepare for steps
-        inv_step_dist = self.stepper.inv_step_dist
-        step_dist = self.stepper.step_dist
         mcu_stepper = self.stepper.mcu_stepper
         mcu_time = mcu_stepper.print_to_mcu_time(move_time)
-        step_pos = mcu_stepper.commanded_position
-        step_offset = step_pos - start_pos * inv_step_dist
 
         # Acceleration steps
-        accel_multiplier = 2.0 * step_dist * inv_accel
         if accel_d:
-            #t = sqrt(2*pos/accel + (start_v/accel)**2) - start_v/accel
-            accel_time_offset = start_v * inv_accel
-            accel_sqrt_offset = accel_time_offset**2
-            accel_steps = accel_d * inv_step_dist
-            count = mcu_stepper.step_sqrt(
-                mcu_time - accel_time_offset, accel_steps, step_offset
-                , accel_sqrt_offset, accel_multiplier)
-            step_offset += count - accel_steps
+            mcu_stepper.step_const(mcu_time, start_pos, accel_d, start_v, accel)
+            start_pos += accel_d
             mcu_time += accel_t
         # Cruising steps
         if cruise_d:
-            #t = pos/cruise_v
-            cruise_multiplier = step_dist / cruise_v
-            cruise_steps = cruise_d * inv_step_dist
-            count = mcu_stepper.step_factor(
-                mcu_time, cruise_steps, step_offset, cruise_multiplier)
-            step_offset += count - cruise_steps
+            mcu_stepper.step_const(mcu_time, start_pos, cruise_d, cruise_v, 0.)
+            start_pos += cruise_d
             mcu_time += cruise_t
         # Deceleration steps
         if decel_d:
-            #t = cruise_v/accel - sqrt((cruise_v/accel)**2 - 2*pos/accel)
-            decel_time_offset = decel_v * inv_accel
-            decel_sqrt_offset = decel_time_offset**2
-            decel_steps = decel_d * inv_step_dist
-            count = mcu_stepper.step_sqrt(
-                mcu_time + decel_time_offset, decel_steps, step_offset
-                , decel_sqrt_offset, -accel_multiplier)
-            step_offset += count - decel_steps
+            mcu_stepper.step_const(mcu_time, start_pos, decel_d, decel_v, -accel)
+            start_pos += decel_d
             mcu_time += decel_t
         # Retraction steps
         if retract_d:
-            #t = sqrt(2*pos/accel + (start_v/accel)**2) - start_v/accel
-            accel_time_offset = retract_v * inv_accel
-            accel_sqrt_offset = accel_time_offset**2
-            accel_steps = -retract_d * inv_step_dist
-            count = mcu_stepper.step_sqrt(
-                mcu_time - accel_time_offset, accel_steps, step_offset
-                , accel_sqrt_offset, accel_multiplier)
+            mcu_stepper.step_const(
+                mcu_time, start_pos, -retract_d, retract_v, accel)
+            start_pos -= retract_d
+        self.extrude_pos = start_pos
 
-        self.extrude_pos = start_pos + accel_d + cruise_d + decel_d - retract_d
+# Dummy extruder class used when a printer has no extruder at all
+class DummyExtruder:
+    def set_max_jerk(self, max_xy_halt_velocity, max_velocity, max_accel):
+        pass
+    def motor_off(self, move_time):
+        pass
+    def check_move(self, move):
+        raise homing.EndstopMoveError(
+            move.end_pos, "Extrude when no extruder present")
+    def calc_junction(self, prev_move, move):
+        return move.max_cruise_v2
+    def lookahead(self, moves, flush_count, lazy):
+        return flush_count

klippy/fan.py

@@ -5,30 +5,27 @@
 # This file may be distributed under the terms of the GNU GPLv3 license.
 
 FAN_MIN_TIME = 0.1
+PWM_CYCLE_TIME = 0.010
 
 class PrinterFan:
     def __init__(self, printer, config):
-        self.printer = printer
-        self.config = config
-        self.mcu_fan = None
-        self.last_fan_value = 0
+        self.last_fan_value = 0.
         self.last_fan_time = 0.
-        self.kick_start_time = config.getfloat('kick_start_time', 0.1)
-    def build_config(self):
-        pin = self.config.get('pin')
-        hard_pwm = self.config.getint('hard_pwm', 128)
-        self.mcu_fan = self.printer.mcu.create_pwm(pin, hard_pwm, 0)
+        self.kick_start_time = config.getfloat('kick_start_time', 0.1, minval=0.)
+        pin = config.get('pin')
+        hard_pwm = config.getint('hard_pwm', 0)
+        self.mcu_fan = printer.mcu.create_pwm(pin, PWM_CYCLE_TIME, hard_pwm, 0.)
     # External commands
     def set_speed(self, print_time, value):
-        value = max(0, min(255, int(value*255. + 0.5)))
+        value = max(0., min(1., value))
         if value == self.last_fan_value:
             return
         mcu_time = self.mcu_fan.print_to_mcu_time(print_time)
         mcu_time = max(self.last_fan_time + FAN_MIN_TIME, mcu_time)
-        if (value and value < 255
+        if (value and value < 1.
             and not self.last_fan_value and self.kick_start_time):
             # Run fan at full speed for specified kick_start_time
-            self.mcu_fan.set_pwm(mcu_time, 255)
+            self.mcu_fan.set_pwm(mcu_time, 1.)
             mcu_time += self.kick_start_time
         self.mcu_fan.set_pwm(mcu_time, value)
         self.last_fan_time = mcu_time

klippy/gcode.py

@@ -3,7 +3,7 @@
 # Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import os, re, logging, collections, time
+import os, re, logging, collections
 import homing
 
 # Parse out incoming GCode and find and translate head movements
@@ -23,7 +23,7 @@ class GCodeParser:
         self.bytes_read = 0
         self.input_log = collections.deque([], 50)
         # Command handling
-        self.gcode_handlers = {}
+        self.gcode_handlers = self.build_handlers(False)
         self.is_printer_ready = False
         self.need_ack = False
         self.toolhead = self.heater_nozzle = self.heater_bed = self.fan = None
@@ -33,50 +33,47 @@ class GCodeParser:
         self.last_position = [0.0, 0.0, 0.0, 0.0]
         self.homing_add = [0.0, 0.0, 0.0, 0.0]
         self.axis2pos = {'X': 0, 'Y': 1, 'Z': 2, 'E': 3}
-        self.build_handlers()
-    def build_config(self):
-        self.toolhead = self.printer.objects['toolhead']
-        self.heater_nozzle = None
-        extruder = self.printer.objects.get('extruder')
-        if extruder:
-            self.heater_nozzle = extruder.heater
-        self.heater_bed = self.printer.objects.get('heater_bed')
-        self.fan = self.printer.objects.get('fan')
-    def build_handlers(self):
-        handlers = ['G1', 'G4', 'G20', 'G21', 'G28', 'G90', 'G91', 'G92',
-                    'M18', 'M82', 'M83', 'M105', 'M110', 'M112', 'M114', 'M206',
-                    'HELP', 'QUERY_ENDSTOPS', 'RESTART', 'CLEAR_SHUTDOWN',
-                    'STATUS']
-        if self.heater_nozzle is not None:
-            handlers.extend(['M104', 'M109', 'PID_TUNE'])
-        if self.heater_bed is not None:
-            handlers.extend(['M140', 'M190'])
-        if self.fan is not None:
-            handlers.extend(['M106', 'M107'])
-        if not self.is_printer_ready:
+    def build_handlers(self, is_ready):
+        handlers = self.all_handlers
+        if not is_ready:
             handlers = [h for h in handlers
                         if getattr(self, 'cmd_'+h+'_when_not_ready', False)]
-        self.gcode_handlers = dict((h, getattr(self, 'cmd_'+h))
-                                   for h in handlers)
-        for h, f in self.gcode_handlers.items():
+        gcode_handlers = dict((h, getattr(self, 'cmd_'+h)) for h in handlers)
+        for h, f in gcode_handlers.items():
             aliases = getattr(self, 'cmd_'+h+'_aliases', [])
-            self.gcode_handlers.update(dict([(a, f) for a in aliases]))
+            gcode_handlers.update(dict([(a, f) for a in aliases]))
+        return gcode_handlers
     def stats(self, eventtime):
         return "gcodein=%d" % (self.bytes_read,)
     def set_printer_ready(self, is_ready):
         if self.is_printer_ready == is_ready:
             return
         self.is_printer_ready = is_ready
-        self.build_handlers()
-        if is_ready and self.is_fileinput and self.fd_handle is None:
+        self.gcode_handlers = self.build_handlers(is_ready)
+        if not is_ready:
+            # Printer is shutdown (could be running in a background thread)
+            return
+        # Lookup printer components
+        self.toolhead = self.printer.objects.get('toolhead')
+        self.heater_nozzle = None
+        extruder = self.printer.objects.get('extruder')
+        if extruder:
+            self.heater_nozzle = extruder.heater
+        self.heater_bed = self.printer.objects.get('heater_bed')
+        self.fan = self.printer.objects.get('fan')
+        if self.is_fileinput and self.fd_handle is None:
             self.fd_handle = self.reactor.register_fd(self.fd, self.process_data)
     def motor_heater_off(self):
-        if self.toolhead is not None:
+        if self.toolhead is None:
+            return
         self.toolhead.motor_off()
+        print_time = self.toolhead.get_last_move_time()
         if self.heater_nozzle is not None:
-            self.heater_nozzle.set_temp(0., 0.)
+            self.heater_nozzle.set_temp(print_time, 0.)
         if self.heater_bed is not None:
-            self.heater_bed.set_temp(0., 0.)
+            self.heater_bed.set_temp(print_time, 0.)
+        if self.fan is not None:
+            self.fan.set_speed(print_time, 0.)
     def dump_debug(self):
         logging.info("Dumping gcode input %d blocks" % (
             len(self.input_log),))
@@ -109,10 +106,15 @@ class GCodeParser:
             handler = self.gcode_handlers.get(cmd, self.cmd_default)
             try:
                 handler(params)
+            except error, e:
+                self.respond_error(str(e))
             except:
                 logging.exception("Exception in command handler")
                 self.toolhead.force_shutdown()
                 self.respond_error('Internal error on command:"%s"' % (cmd,))
+                if self.is_fileinput:
+                    self.printer.request_exit('exit_eof')
+                    break
             self.ack()
     def process_data(self, eventtime):
         data = os.read(self.fd, 4096)
@@ -136,7 +138,7 @@ class GCodeParser:
             self.fd_handle = self.reactor.register_fd(self.fd, self.process_data)
         if not data and self.is_fileinput:
             self.motor_heater_off()
-            self.printer.request_exit_eof()
+            self.printer.request_exit('exit_eof')
     # Response handling
     def ack(self, msg=None):
         if not self.need_ack or self.is_fileinput:
@@ -159,6 +161,27 @@ class GCodeParser:
         if len(lines) > 1:
             self.respond_info("\n".join(lines[:-1]))
         self.respond('!! %s' % (lines[-1].strip(),))
+    # Parameter parsing helpers
+    def get_int(self, name, params, default=None):
+        if name in params:
+            try:
+                return int(params[name])
+            except ValueError:
+                raise error("Error on '%s': unable to parse %s" % (
+                    params['#original'], params[name]))
+        if default is not None:
+            return default
+        raise error("Error on '%s': missing %s" % (params['#original'], name))
+    def get_float(self, name, params, default=None):
+        if name in params:
+            try:
+                return float(params[name])
+            except ValueError:
+                raise error("Error on '%s': unable to parse %s" % (
+                    params['#original'], params[name]))
+        if default is not None:
+            return default
+        raise error("Error on '%s': missing %s" % (params['#original'], name))
     # Temperature wrappers
     def get_temp(self):
         if not self.is_printer_ready:
@@ -175,17 +198,32 @@ class GCodeParser:
     def bg_temp(self, heater):
         if self.is_fileinput:
             return
-        eventtime = time.time()
+        eventtime = self.reactor.monotonic()
         while self.is_printer_ready and heater.check_busy(eventtime):
-            self.toolhead.reset_motor_off_time(eventtime)
+            print_time = self.toolhead.get_last_move_time()
             self.respond(self.get_temp())
             eventtime = self.reactor.pause(eventtime + 1.)
     def set_temp(self, heater, params, wait=False):
+        temp = self.get_float('S', params, 0.)
+        if heater is None:
+            if temp > 0.:
+                self.respond_error("Heater not configured")
+            return
         print_time = self.toolhead.get_last_move_time()
-        temp = float(params.get('S', '0'))
+        try:
             heater.set_temp(print_time, temp)
+        except heater.error, e:
+            self.respond_error(str(e))
+            return
         if wait:
             self.bg_temp(heater)
+    def set_fan_speed(self, speed):
+        if self.fan is None:
+            if speed:
+                self.respond_info("Fan not configured")
+            return
+        print_time = self.toolhead.get_last_move_time()
+        self.fan.set_speed(print_time, speed)
     # Individual command handlers
     def cmd_default(self, params):
         if not self.is_printer_ready:
@@ -196,20 +234,34 @@ class GCodeParser:
             logging.debug(params['#original'])
             return
         self.respond('echo:Unknown command:"%s"' % (cmd,))
+    all_handlers = [
+        'G1', 'G4', 'G20', 'G28', 'G90', 'G91', 'G92',
+        'M82', 'M83', 'M18', 'M105', 'M104', 'M109', 'M112', 'M114', 'M115',
+        'M140', 'M190', 'M106', 'M107', 'M206', 'M400',
+        'IGNORE', 'QUERY_ENDSTOPS', 'PID_TUNE', 'RESTART', 'FIRMWARE_RESTART',
+        'STATUS', 'HELP']
     cmd_G1_aliases = ['G0']
     def cmd_G1(self, params):
         # Move
+        try:
             for a, p in self.axis2pos.items():
                 if a in params:
                     v = float(params[a])
-                if not self.absolutecoord or (p>2 and not self.absoluteextrude):
+                    if (not self.absolutecoord
+                        or (p>2 and not self.absoluteextrude)):
                         # value relative to position of last move
                         self.last_position[p] += v
                     else:
                         # value relative to base coordinate position
                         self.last_position[p] = v + self.base_position[p]
             if 'F' in params:
-            self.speed = float(params['F']) / 60.
+                speed = float(params['F']) / 60.
+                if speed <= 0.:
+                    raise ValueError()
+                self.speed = speed
+        except ValueError, e:
+            self.last_position = self.toolhead.get_position()
+            raise error("Unable to parse move '%s'" % (params['#original'],))
         try:
             self.toolhead.move(self.last_position, self.speed)
         except homing.EndstopError, e:
@@ -218,16 +270,13 @@ class GCodeParser:
     def cmd_G4(self, params):
         # Dwell
         if 'S' in params:
-            delay = float(params['S'])
+            delay = self.get_float('S', params)
         else:
-            delay = float(params.get('P', '0')) / 1000.
+            delay = self.get_float('P', params, 0.) / 1000.
         self.toolhead.dwell(delay)
     def cmd_G20(self, params):
         # Set units to inches
         self.respond_error('Machine does not support G20 (inches) command')
-    def cmd_G21(self, params):
-        # Set units to millimeters
-        pass
     def cmd_G28(self, params):
         # Move to origin
         axes = []
@@ -257,12 +306,11 @@ class GCodeParser:
         self.absolutecoord = False
     def cmd_G92(self, params):
         # Set position
-        mcount = 0
-        for a, p in self.axis2pos.items():
-            if a in params:
-                self.base_position[p] = self.last_position[p] - float(params[a])
-                mcount += 1
-        if not mcount:
+        offsets = { p: self.get_float(a, params)
+                    for a, p in self.axis2pos.items() if a in params }
+        for p, offset in offsets.items():
+            self.base_position[p] = self.last_position[p] - offset
+        if not offsets:
             self.base_position = list(self.last_position)
     def cmd_M82(self, params):
         # Use absolute distances for extrusion
@@ -284,10 +332,6 @@ class GCodeParser:
     def cmd_M109(self, params):
         # Set Extruder Temperature and Wait
         self.set_temp(self.heater_nozzle, params, wait=True)
-    cmd_M110_when_not_ready = True
-    def cmd_M110(self, params):
-        # Set Current Line Number
-        pass
     def cmd_M112(self, params):
         # Emergency Stop
         self.toolhead.force_shutdown()
@@ -302,6 +346,12 @@ class GCodeParser:
             self.last_position[0], self.last_position[1],
             self.last_position[2], self.last_position[3],
             kinpos[0], kinpos[1], kinpos[2]))
+    cmd_M115_when_not_ready = True
+    def cmd_M115(self, params):
+        # Get Firmware Version and Capabilities
+        kw = {"FIRMWARE_NAME": "Klipper"
+              , "FIRMWARE_VERSION": self.printer.software_version}
+        self.ack(" ".join(["%s:%s" % (k, v) for k, v in kw.items()]))
     def cmd_M140(self, params):
         # Set Bed Temperature
         self.set_temp(self.heater_bed, params)
@@ -310,19 +360,25 @@ class GCodeParser:
         self.set_temp(self.heater_bed, params, wait=True)
     def cmd_M106(self, params):
         # Set fan speed
-        print_time = self.toolhead.get_last_move_time()
-        self.fan.set_speed(print_time, float(params.get('S', '255')) / 255.)
+        self.set_fan_speed(self.get_float('S', params, 255.) / 255.)
     def cmd_M107(self, params):
         # Turn fan off
-        print_time = self.toolhead.get_last_move_time()
-        self.fan.set_speed(print_time, 0)
+        self.set_fan_speed(0.)
     def cmd_M206(self, params):
         # Set home offset
-        for a, p in self.axis2pos.items():
-            if a in params:
-                v = float(params[a])
-                self.base_position[p] += self.homing_add[p] - v
-                self.homing_add[p] = v
+        offsets = { p: self.get_float(a, params)
+                    for a, p in self.axis2pos.items() if a in params }
+        for p, offset in offsets.items():
+            self.base_position[p] += self.homing_add[p] - offset
+            self.homing_add[p] = offset
+    def cmd_M400(self, params):
+        # Wait for current moves to finish
+        self.toolhead.wait_moves()
+    cmd_IGNORE_when_not_ready = True
+    cmd_IGNORE_aliases = ["G21", "M110", "M21"]
+    def cmd_IGNORE(self, params):
+        # Commands that are just silently accepted
+        pass
     cmd_QUERY_ENDSTOPS_help = "Report on the status of each endstop"
     cmd_QUERY_ENDSTOPS_aliases = ["M119"]
     def cmd_QUERY_ENDSTOPS(self, params):
@@ -340,23 +396,29 @@ class GCodeParser:
     cmd_PID_TUNE_aliases = ["M303"]
     def cmd_PID_TUNE(self, params):
         # Run PID tuning
-        heater = int(params.get('E', '0'))
+        heater = self.get_int('E', params, 0)
         heater = {0: self.heater_nozzle, -1: self.heater_bed}[heater]
-        temp = float(params.get('S', '60'))
+        if heater is None:
+            self.respond_error("Heater not configured")
+        temp = self.get_float('S', params)
         heater.start_auto_tune(temp)
         self.bg_temp(heater)
-    cmd_CLEAR_SHUTDOWN_when_not_ready = True
-    cmd_CLEAR_SHUTDOWN_help = "Clear a firmware shutdown and restart"
-    def cmd_CLEAR_SHUTDOWN(self, params):
-        if self.toolhead is None:
-            self.cmd_default(params)
-            return
-        self.printer.mcu.clear_shutdown()
-        self.printer.request_restart()
+    def prep_restart(self):
+        if self.is_printer_ready:
+            self.respond_info("Preparing to restart...")
+            self.motor_heater_off()
+            self.toolhead.dwell(0.500)
+            self.toolhead.wait_moves()
     cmd_RESTART_when_not_ready = True
     cmd_RESTART_help = "Reload config file and restart host software"
     def cmd_RESTART(self, params):
-        self.printer.request_restart()
+        self.prep_restart()
+        self.printer.request_exit('restart')
+    cmd_FIRMWARE_RESTART_when_not_ready = True
+    cmd_FIRMWARE_RESTART_help = "Restart firmware, host, and reload config"
+    def cmd_FIRMWARE_RESTART(self, params):
+        self.prep_restart()
+        self.printer.request_exit('firmware_restart')
     cmd_STATUS_when_not_ready = True
     cmd_STATUS_help = "Report the printer status"
     def cmd_STATUS(self, params):
@@ -371,8 +433,11 @@ class GCodeParser:
         if not self.is_printer_ready:
             cmdhelp.append("Printer is not ready - not all commands available.")
         cmdhelp.append("Available extended commands:")
-        for cmd in self.gcode_handlers:
+        for cmd in sorted(self.gcode_handlers):
             desc = getattr(self, 'cmd_'+cmd+'_help', None)
             if desc is not None:
                 cmdhelp.append("%-10s: %s" % (cmd, desc))
         self.respond_info("\n".join(cmdhelp))
+
+class error(Exception):
+    pass

klippy/heater.py

@@ -5,84 +5,110 @@
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import math, logging, threading
 
-# Mapping from name to Steinhart-Hart coefficients
-Thermistors = {
+# Available sensors
+Sensors = {
+    # Common thermistors and their Steinhart-Hart coefficients
     "EPCOS 100K B57560G104F": (
+        "thermistor",
         0.000722136308968056, 0.000216766566488498, 8.92935804531095e-08),
     "ATC Semitec 104GT-2": (
+        "thermistor",
         0.000809651054275124, 0.000211636030735685, 7.07420883993973e-08),
+    # Linear style conversion chips and their gain/offset
+    "AD595": ("linear", 300.0 / 3.022, 0.),
 }
 
 SAMPLE_TIME = 0.001
 SAMPLE_COUNT = 8
 REPORT_TIME = 0.300
+PWM_CYCLE_TIME = 0.100
 KELVIN_TO_CELCIUS = -273.15
 MAX_HEAT_TIME = 5.0
 AMBIENT_TEMP = 25.
-PWM_MAX = 255
+PID_PARAM_BASE = 255.
+
+class error(Exception):
+    pass
 
 class PrinterHeater:
+    error = error
     def __init__(self, printer, config):
-        self.printer = printer
-        self.config = config
-        self.mcu_pwm = self.mcu_adc = None
-        self.thermistor_c = config.getchoice('thermistor_type', Thermistors)
-        self.pullup_r = config.getfloat('pullup_resistor', 4700.)
-        self.min_extrude_temp = config.getfloat('min_extrude_temp', 170.)
-        self.can_extrude = (self.min_extrude_temp <= 0.)
+        self.name = config.section
+        sensor_params = config.getchoice('sensor_type', Sensors)
+        self.is_linear_sensor = (sensor_params[0] == 'linear')
+        if self.is_linear_sensor:
+            adc_voltage = config.getfloat('adc_voltage', 5., above=0.)
+            self.sensor_coef = sensor_params[1] * adc_voltage, sensor_params[2]
+        else:
+            pullup = config.getfloat('pullup_resistor', 4700., above=0.)
+            self.sensor_coef = sensor_params[1:] + (pullup,)
+        self.min_temp = config.getfloat('min_temp', minval=0.)
+        self.max_temp = config.getfloat('max_temp', above=self.min_temp)
+        self.min_extrude_temp = config.getfloat(
+            'min_extrude_temp', 170., minval=self.min_temp, maxval=self.max_temp)
+        self.max_power = config.getfloat('max_power', 1., above=0., maxval=1.)
+        self.can_extrude = (self.min_extrude_temp <= 0.
+                            or printer.mcu.is_fileoutput())
         self.lock = threading.Lock()
         self.last_temp = 0.
         self.last_temp_time = 0.
         self.target_temp = 0.
-        self.control = None
+        algos = {'watermark': ControlBangBang, 'pid': ControlPID}
+        algo = config.getchoice('control', algos)
+        heater_pin = config.get('heater_pin')
+        sensor_pin = config.get('sensor_pin')
+        if algo is ControlBangBang and self.max_power == 1.:
+            self.mcu_pwm = printer.mcu.create_digital_out(
+                heater_pin, MAX_HEAT_TIME)
+        else:
+            self.mcu_pwm = printer.mcu.create_pwm(
+                heater_pin, PWM_CYCLE_TIME, 0, MAX_HEAT_TIME)
+        self.mcu_adc = printer.mcu.create_adc(sensor_pin)
+        adc_range = [self.calc_adc(self.min_temp), self.calc_adc(self.max_temp)]
+        self.mcu_adc.set_minmax(SAMPLE_TIME, SAMPLE_COUNT,
+                                minval=min(adc_range), maxval=max(adc_range))
+        self.mcu_adc.set_adc_callback(REPORT_TIME, self.adc_callback)
+        self.control = algo(self, config)
         # pwm caching
         self.next_pwm_time = 0.
         self.last_pwm_value = 0
-    def build_config(self):
-        heater_pin = self.config.get('heater_pin')
-        thermistor_pin = self.config.get('thermistor_pin')
-        self.mcu_pwm = self.printer.mcu.create_pwm(heater_pin, 0, MAX_HEAT_TIME)
-        self.mcu_adc = self.printer.mcu.create_adc(thermistor_pin)
-        min_adc = self.calc_adc(self.config.getfloat('max_temp'))
-        max_adc = self.calc_adc(self.config.getfloat('min_temp'))
-        self.mcu_adc.set_minmax(
-            SAMPLE_TIME, SAMPLE_COUNT, minval=min_adc, maxval=max_adc)
-        self.mcu_adc.set_adc_callback(REPORT_TIME, self.adc_callback)
-        algos = {'watermark': ControlBangBang, 'pid': ControlPID}
-        self.control = self.config.getchoice('control', algos)(self, self.config)
-        if self.printer.mcu.is_fileoutput():
-            self.can_extrude = True
     def set_pwm(self, read_time, value):
-        if value:
         if self.target_temp <= 0.:
-                return
-            if (read_time < self.next_pwm_time
-                and abs(value - self.last_pwm_value) < 15):
-                return
-        elif not self.last_pwm_value:
+            value = 0.
+        if ((read_time < self.next_pwm_time or not self.last_pwm_value)
+            and abs(value - self.last_pwm_value) < 0.05):
+            # No significant change in value - can suppress update
             return
         pwm_time = read_time + REPORT_TIME + SAMPLE_TIME*SAMPLE_COUNT
         self.next_pwm_time = pwm_time + 0.75 * MAX_HEAT_TIME
         self.last_pwm_value = value
-        logging.debug("pwm=%d@%.3f (%.3f)" % (value, read_time, pwm_time))
+        logging.debug("%s: pwm=%.3f@%.3f (from %.3f@%.3f [%.3f])" % (
+            self.name, value, pwm_time,
+            self.last_temp, self.last_temp_time, self.target_temp))
         self.mcu_pwm.set_pwm(pwm_time, value)
     # Temperature calculation
     def calc_temp(self, adc):
-        r = self.pullup_r * adc / (1.0 - adc)
+        if self.is_linear_sensor:
+            gain, offset = self.sensor_coef
+            return adc * gain + offset
+        c1, c2, c3, pullup = self.sensor_coef
+        r = pullup * adc / (1.0 - adc)
         ln_r = math.log(r)
-        c1, c2, c3 = self.thermistor_c
         temp_inv = c1 + c2*ln_r + c3*math.pow(ln_r, 3)
         return 1.0/temp_inv + KELVIN_TO_CELCIUS
     def calc_adc(self, temp):
         if temp is None:
             return None
-        c1, c2, c3 = self.thermistor_c
+        if self.is_linear_sensor:
+            gain, offset = self.sensor_coef
+            return (temp - offset) / gain
+        c1, c2, c3, pullup = self.sensor_coef
         temp -= KELVIN_TO_CELCIUS
         temp_inv = 1./temp
         y = (c1 - temp_inv) / (2*c3)
         x = math.sqrt(math.pow(c2 / (3.*c3), 3.) + math.pow(y, 2.))
         r = math.exp(math.pow(x-y, 1./3.) - math.pow(x+y, 1./3.))
-        return r / (self.pullup_r + r)
+        return r / (pullup + r)
     def adc_callback(self, read_time, read_value):
         temp = self.calc_temp(read_value)
         with self.lock:
@@ -93,6 +119,9 @@ class PrinterHeater:
         #logging.debug("temp: %.3f %f = %f" % (read_time, read_value, temp))
     # External commands
     def set_temp(self, print_time, degrees):
+        if degrees and (degrees < self.min_temp or degrees > self.max_temp):
+            raise error("Requested temperature (%.1f) out of range (%.1f:%.1f)"
+                        % (degrees, self.min_temp, self.max_temp))
         with self.lock:
             self.target_temp = degrees
     def get_temp(self):
@@ -113,7 +142,7 @@ class PrinterHeater:
 class ControlBangBang:
     def __init__(self, heater, config):
         self.heater = heater
-        self.max_delta = config.getfloat('max_delta', 2.0)
+        self.max_delta = config.getfloat('max_delta', 2.0, above=0.)
         self.heating = False
     def adc_callback(self, read_time, temp):
         if self.heating and temp >= self.heater.target_temp+self.max_delta:
@@ -121,9 +150,9 @@ class ControlBangBang:
         elif not self.heating and temp <= self.heater.target_temp-self.max_delta:
             self.heating = True
         if self.heating:
-            self.heater.set_pwm(read_time, PWM_MAX)
+            self.heater.set_pwm(read_time, self.heater.max_power)
         else:
-            self.heater.set_pwm(read_time, 0)
+            self.heater.set_pwm(read_time, 0.)
     def check_busy(self, eventtime):
         return self.heater.last_temp < self.heater.target_temp-self.max_delta
 
@@ -135,11 +164,11 @@ class ControlBangBang:
 class ControlPID:
     def __init__(self, heater, config):
         self.heater = heater
-        self.Kp = config.getfloat('pid_Kp')
-        self.Ki = config.getfloat('pid_Ki')
-        self.Kd = config.getfloat('pid_Kd')
-        self.min_deriv_time = config.getfloat('pid_deriv_time', 2.)
-        imax = config.getint('pid_integral_max', PWM_MAX)
+        self.Kp = config.getfloat('pid_Kp') / PID_PARAM_BASE
+        self.Ki = config.getfloat('pid_Ki') / PID_PARAM_BASE
+        self.Kd = config.getfloat('pid_Kd') / PID_PARAM_BASE
+        self.min_deriv_time = config.getfloat('pid_deriv_time', 2., above=0.)
+        imax = config.getfloat('pid_integral_max', heater.max_power, minval=0.)
         self.temp_integ_max = imax / self.Ki
         self.prev_temp = AMBIENT_TEMP
         self.prev_temp_time = 0.
@@ -159,10 +188,10 @@ class ControlPID:
         temp_integ = self.prev_temp_integ + temp_err * time_diff
         temp_integ = max(0., min(self.temp_integ_max, temp_integ))
         # Calculate output
-        co = int(self.Kp*temp_err + self.Ki*temp_integ - self.Kd*temp_deriv)
+        co = self.Kp*temp_err + self.Ki*temp_integ - self.Kd*temp_deriv
         #logging.debug("pid: %f@%.3f -> diff=%f deriv=%f err=%f integ=%f co=%d" % (
         #    temp, read_time, temp_diff, temp_deriv, temp_err, temp_integ, co))
-        bounded_co = max(0, min(PWM_MAX, co))
+        bounded_co = max(0., min(self.heater.max_power, co))
         self.heater.set_pwm(read_time, bounded_co)
         # Store state for next measurement
         self.prev_temp = temp
@@ -198,12 +227,12 @@ class ControlAutoTune:
             self.heating = True
             self.check_peaks()
         if self.heating:
-            self.heater.set_pwm(read_time, PWM_MAX)
+            self.heater.set_pwm(read_time, self.heater.max_power)
             if temp < self.peak:
                 self.peak = temp
                 self.peak_time = read_time
         else:
-            self.heater.set_pwm(read_time, 0)
+            self.heater.set_pwm(read_time, 0.)
             if temp > self.peak:
                 self.peak = temp
                 self.peak_time = read_time
@@ -217,8 +246,8 @@ class ControlAutoTune:
             return
         temp_diff = self.peaks[-1][0] - self.peaks[-2][0]
         time_diff = self.peaks[-1][1] - self.peaks[-3][1]
-        pwm_diff = PWM_MAX - 0
-        Ku = 4. * (2. * pwm_diff) / (abs(temp_diff) * math.pi)
+        max_power = self.heater.max_power
+        Ku = 4. * (2. * max_power) / (abs(temp_diff) * math.pi)
         Tu = time_diff
 
         Kp = 0.6 * Ku
@@ -226,8 +255,9 @@ class ControlAutoTune:
         Td = 0.125 * Tu
         Ki = Kp / Ti
         Kd = Kp * Td
-        logging.info("Autotune: raw=%f/%d Ku=%f Tu=%f  Kp=%f Ki=%f Kd=%f" % (
-            temp_diff, pwm_diff, Ku, Tu, Kp, Ki, Kd))
+        logging.info("Autotune: raw=%f/%f Ku=%f Tu=%f  Kp=%f Ki=%f Kd=%f" % (
+            temp_diff, max_power, Ku, Tu,
+            Kp * PID_PARAM_BASE, Ki * PID_PARAM_BASE, Kd * PID_PARAM_BASE))
     def check_busy(self, eventtime):
         if self.heating or len(self.peaks) < 12:
             return True
@@ -253,17 +283,17 @@ class ControlBumpTest:
     def adc_callback(self, read_time, temp):
         self.temp_samples[read_time] = temp
         if not self.state:
-            self.set_pwm(read_time, 0)
+            self.set_pwm(read_time, 0.)
             if len(self.temp_samples) >= 20:
                 self.state += 1
         elif self.state == 1:
             if temp < self.target_temp:
-                self.set_pwm(read_time, PWM_MAX)
+                self.set_pwm(read_time, self.heater.max_power)
                 return
-            self.set_pwm(read_time, 0)
+            self.set_pwm(read_time, 0.)
             self.state += 1
         elif self.state == 2:
-            self.set_pwm(read_time, 0)
+            self.set_pwm(read_time, 0.)
             if temp <= (self.target_temp + AMBIENT_TEMP) / 2.:
                 self.dump_stats()
                 self.state += 1

klippy/klippy.py

@@ -6,6 +6,9 @@
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import sys, optparse, ConfigParser, logging, time, threading
 import gcode, toolhead, util, mcu, fan, heater, extruder, reactor, queuelogger
+import msgproto
+
+message_ready = "Printer is ready"
 
 message_startup = """
 The klippy host software is attempting to connect.  Please
@@ -19,17 +22,26 @@ command to reload the config and restart the host software.
 Printer is halted
 """
 
+message_protocol_error = """
+This type of error is frequently caused by running an older
+version of the firmware on the micro-controller (fix by
+recompiling and flashing the firmware).
+Once the underlying issue is corrected, use the "RESTART"
+command to reload the config and restart the host software.
+Protocol error connecting to printer
+"""
+
 message_mcu_connect_error = """
-This is an unrecoverable error.  Please manually restart the
-micro-controller and then issue the "RESTART" command to
-restart the host software.
+Once the underlying issue is corrected, use the
+"FIRMWARE_RESTART" command to reset the firmware, reload the
+config, and restart the host software.
 Error configuring printer
 """
 
 message_shutdown = """
-Once the underlying issue is corrected, the "CLEAR_SHUTDOWN"
-command can be used to clear the firmware flag and restart
-the host software.
+Once the underlying issue is corrected, use the
+"FIRMWARE_RESTART" command to reset the firmware, reload the
+config, and restart the host software.
 Printer is shutdown
 """
 
@@ -40,26 +52,47 @@ class ConfigWrapper:
     def __init__(self, printer, section):
         self.printer = printer
         self.section = section
-    def get_wrapper(self, parser, option, default):
+    def get_wrapper(self, parser, option, default
+                    , minval=None, maxval=None, above=None, below=None):
         if (default is not self.sentinel
             and not self.printer.fileconfig.has_option(self.section, option)):
             return default
         self.printer.all_config_options[
             (self.section.lower(), option.lower())] = 1
         try:
-            return parser(self.section, option)
+            v = parser(self.section, option)
         except self.error, e:
             raise
         except:
             raise self.error("Unable to parse option '%s' in section '%s'" % (
                 option, self.section))
+        if minval is not None and v < minval:
+            raise self.error(
+                "Option '%s' in section '%s' must have minimum of %s" % (
+                    option, self.section, minval))
+        if maxval is not None and v > maxval:
+            raise self.error(
+                "Option '%s' in section '%s' must have maximum of %s" % (
+                    option, self.section, maxval))
+        if above is not None and v <= above:
+            raise self.error(
+                "Option '%s' in section '%s' must be above %s" % (
+                    option, self.section, above))
+        if below is not None and v >= below:
+            raise self.error(
+                "Option '%s' in section '%s' must be below %s" % (
+                    option, self.section, below))
+        return v
     def get(self, option, default=sentinel):
         return self.get_wrapper(self.printer.fileconfig.get, option, default)
-    def getint(self, option, default=sentinel):
-        return self.get_wrapper(self.printer.fileconfig.getint, option, default)
-    def getfloat(self, option, default=sentinel):
+    def getint(self, option, default=sentinel, minval=None, maxval=None):
         return self.get_wrapper(
-            self.printer.fileconfig.getfloat, option, default)
+            self.printer.fileconfig.getint, option, default, minval, maxval)
+    def getfloat(self, option, default=sentinel
+                 , minval=None, maxval=None, above=None, below=None):
+        return self.get_wrapper(
+            self.printer.fileconfig.getfloat, option, default
+            , minval, maxval, above, below)
     def getboolean(self, option, default=sentinel):
         return self.get_wrapper(
             self.printer.fileconfig.getboolean, option, default)
@@ -73,10 +106,28 @@ class ConfigWrapper:
     def getsection(self, section):
         return ConfigWrapper(self.printer, section)
 
+class ConfigLogger():
+    def __init__(self, cfg, bglogger):
+        self.lines = ["===== Config file ====="]
+        cfg.write(self)
+        self.lines.append("=======================")
+        data = "\n".join(self.lines)
+        logging.info(data)
+        bglogger.set_rollover_info("config", data)
+    def write(self, data):
+        self.lines.append(data.strip())
+
 class Printer:
-    def __init__(self, conffile, input_fd, is_fileinput=False):
+    def __init__(self, conffile, input_fd, startup_state
+                 , is_fileinput=False, version="?", bglogger=None):
         self.conffile = conffile
+        self.startup_state = startup_state
+        self.software_version = version
+        self.bglogger = bglogger
+        if bglogger is not None:
+            bglogger.set_rollover_info("config", None)
         self.reactor = reactor.Reactor()
+        self.objects = {}
         self.gcode = gcode.GCodeParser(self, input_fd, is_fileinput)
         self.stats_timer = self.reactor.register_timer(self.stats)
         self.connect_timer = self.reactor.register_timer(
@@ -88,23 +139,25 @@ class Printer:
         self.run_result = None
         self.fileconfig = None
         self.mcu = None
-        self.objects = {}
     def set_fileoutput(self, debugoutput, dictionary):
         self.debugoutput = debugoutput
         self.dictionary = dictionary
-    def stats(self, eventtime):
+    def stats(self, eventtime, force_output=False):
         if self.need_dump_debug:
             # Call dump_debug here so it is executed in the main thread
             self.gcode.dump_debug()
             self.need_dump_debug = False
+        toolhead = self.objects.get('toolhead')
+        if toolhead is None or self.mcu is None:
+            return
+        is_active, thstats = toolhead.stats(eventtime)
+        if not is_active and not force_output:
+            return
         out = []
         out.append(self.gcode.stats(eventtime))
-        toolhead = self.objects.get('toolhead')
-        if toolhead is not None:
-            out.append(toolhead.stats(eventtime))
-        if self.mcu is not None:
+        out.append(thstats)
         out.append(self.mcu.stats(eventtime))
-        logging.info("Stats %.0f: %s" % (eventtime, ' '.join(out)))
+        logging.info("Stats %.1f: %s" % (eventtime, ' '.join(out)))
         return eventtime + 1.
     def load_config(self):
         self.fileconfig = ConfigParser.RawConfigParser()
@@ -112,24 +165,23 @@ class Printer:
         if not res:
             raise ConfigParser.Error("Unable to open config file %s" % (
                 self.conffile,))
+        if self.bglogger is not None:
+            ConfigLogger(self.fileconfig, self.bglogger)
         self.mcu = mcu.MCU(self, ConfigWrapper(self, 'mcu'))
-        if self.fileconfig.has_section('fan'):
-            self.objects['fan'] = fan.PrinterFan(
-                self, ConfigWrapper(self, 'fan'))
+        if self.debugoutput is not None:
+            self.mcu.connect_file(self.debugoutput, self.dictionary)
         if self.fileconfig.has_section('extruder'):
             self.objects['extruder'] = extruder.PrinterExtruder(
                 self, ConfigWrapper(self, 'extruder'))
+        if self.fileconfig.has_section('fan'):
+            self.objects['fan'] = fan.PrinterFan(
+                self, ConfigWrapper(self, 'fan'))
         if self.fileconfig.has_section('heater_bed'):
             self.objects['heater_bed'] = heater.PrinterHeater(
                 self, ConfigWrapper(self, 'heater_bed'))
         self.objects['toolhead'] = toolhead.ToolHead(
             self, ConfigWrapper(self, 'printer'))
-    def build_config(self):
-        for oname in sorted(self.objects.keys()):
-            self.objects[oname].build_config()
-        self.gcode.build_config()
-        self.mcu.build_config()
-    def validate_config(self):
+        # Validate that there are no undefined parameters in the config file
         valid_sections = dict([(s, 1) for s, o in self.all_config_options])
         for section in self.fileconfig.sections():
             section = section.lower()
@@ -147,17 +199,17 @@ class Printer:
             self.load_config()
             if self.debugoutput is None:
                 self.reactor.update_timer(self.stats_timer, self.reactor.NOW)
-            else:
-                self.mcu.connect_file(self.debugoutput, self.dictionary)
             self.mcu.connect()
-            self.build_config()
-            self.validate_config()
             self.gcode.set_printer_ready(True)
-            self.state_message = "Printer is ready"
+            self.state_message = message_ready
         except ConfigParser.Error, e:
             logging.exception("Config error")
             self.state_message = "%s%s" % (str(e), message_restart)
             self.reactor.update_timer(self.stats_timer, self.reactor.NEVER)
+        except msgproto.error, e:
+            logging.exception("Protocol error")
+            self.state_message = "%s%s" % (str(e), message_protocol_error)
+            self.reactor.update_timer(self.stats_timer, self.reactor.NEVER)
         except mcu.error, e:
             logging.exception("MCU error during connect")
             self.state_message = "%s%s" % (str(e), message_mcu_connect_error)
@@ -170,6 +222,10 @@ class Printer:
         self.reactor.unregister_timer(self.connect_timer)
         return self.reactor.NEVER
     def run(self):
+        systime = time.time()
+        monotime = self.reactor.monotonic()
+        logging.info("Start printer at %s (%.1f %.1f)" % (
+            time.asctime(time.localtime(systime)), systime, monotime))
         try:
             self.reactor.run()
         except:
@@ -179,7 +235,7 @@ class Printer:
     def get_state_message(self):
         return self.state_message
     def note_shutdown(self, msg):
-        if self.state_message == 'Running':
+        if self.state_message == message_ready:
             self.need_dump_debug = True
         self.state_message = "Firmware shutdown: %s%s" % (
             msg, message_shutdown)
@@ -191,15 +247,22 @@ class Printer:
     def disconnect(self):
         try:
             if self.mcu is not None:
-                self.stats(time.time())
+                self.stats(self.reactor.monotonic(), force_output=True)
                 self.mcu.disconnect()
         except:
             logging.exception("Unhandled exception during disconnect")
-    def request_restart(self):
-        self.run_result = "restart"
-        self.reactor.end()
-    def request_exit_eof(self):
-        self.run_result = "exit_eof"
+    def firmware_restart(self):
+        try:
+            if self.mcu is not None:
+                self.stats(self.reactor.monotonic(), force_output=True)
+                self.mcu.microcontroller_restart()
+                self.mcu.disconnect()
+        except:
+            logging.exception("Unhandled exception during firmware_restart")
+    def get_startup_state(self):
+        return self.startup_state
+    def request_exit(self, result="exit"):
+        self.run_result = result
         self.reactor.end()
 
 
@@ -250,11 +313,22 @@ def main():
     else:
         logging.basicConfig(level=debuglevel)
     logging.info("Starting Klippy...")
+    software_version = util.get_git_version()
+    if bglogger is not None:
+        lines = ["Args: %s" % (sys.argv,),
+                 "Git version: %s" % (repr(software_version),),
+                 "CPU: %s" % (util.get_cpu_info(),),
+                 "Python: %s" % (repr(sys.version),)]
+        lines = "\n".join(lines)
+        logging.info(lines)
+        bglogger.set_rollover_info('versions', lines)
 
     # Start firmware
+    res = 'startup'
     while 1:
         is_fileinput = debuginput is not None
-        printer = Printer(conffile, input_fd, is_fileinput)
+        printer = Printer(
+            conffile, input_fd, res, is_fileinput, software_version, bglogger)
         if debugoutput:
             proto_dict = read_dictionary(options.read_dictionary)
             printer.set_fileoutput(debugoutput, proto_dict)
@@ -264,6 +338,11 @@ def main():
             time.sleep(1.)
             logging.info("Restarting printer")
             continue
+        elif res == 'firmware_restart':
+            printer.firmware_restart()
+            time.sleep(1.)
+            logging.info("Restarting printer")
+            continue
         elif res == 'exit_eof':
             printer.disconnect()
         break

klippy/mcu.py

@@ -1,9 +1,9 @@
 # Multi-processor safe interface to micro-controller
 #
-# Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import sys, zlib, logging, time, math
+import sys, os, zlib, logging, math
 import serialhdl, pins, chelper
 
 class error(Exception):
@@ -19,139 +19,181 @@ def parse_pin_extras(pin, can_pullup=False):
         pin = pin[1:].strip()
     return pin, pullup, invert
 
+STEPCOMPRESS_ERROR_RET = -989898989
+
 class MCU_stepper:
-    def __init__(self, mcu, step_pin, dir_pin, min_stop_interval, max_error):
+    def __init__(self, mcu, step_pin, dir_pin):
         self._mcu = mcu
-        self._oid = mcu.create_oid()
-        step_pin, pullup, invert_step = parse_pin_extras(step_pin)
-        dir_pin, pullup, self._invert_dir = parse_pin_extras(dir_pin)
-        self._mcu_freq = mcu.get_mcu_freq()
-        min_stop_interval = int(min_stop_interval * self._mcu_freq)
-        max_error = int(max_error * self._mcu_freq)
-        self.commanded_position = 0
+        self._oid = mcu.create_oid(self)
+        self._step_pin, pullup, self._invert_step = parse_pin_extras(step_pin)
+        self._dir_pin, pullup, self._invert_dir = parse_pin_extras(dir_pin)
+        self._commanded_pos = 0
+        self._step_dist = self._inv_step_dist = 1.
+        self._velocity_factor = self._accel_factor = 0.
         self._mcu_position_offset = 0
-        mcu.add_config_cmd(
-            "config_stepper oid=%d step_pin=%s dir_pin=%s"
-            " min_stop_interval=%d invert_step=%d" % (
-                self._oid, step_pin, dir_pin, min_stop_interval, invert_step))
-        mcu.register_stepper(self)
-        self._step_cmd = mcu.lookup_command(
-            "queue_step oid=%c interval=%u count=%hu add=%hi")
-        self._dir_cmd = mcu.lookup_command(
-            "set_next_step_dir oid=%c dir=%c")
-        self._reset_cmd = mcu.lookup_command(
-            "reset_step_clock oid=%c clock=%u")
-        ffi_main, self.ffi_lib = chelper.get_ffi()
-        self._stepqueue = ffi_main.gc(self.ffi_lib.stepcompress_alloc(
-            max_error, self._step_cmd.msgid
-            , self._dir_cmd.msgid, self._invert_dir, self._oid),
-                                      self.ffi_lib.stepcompress_free)
+        self._mcu_freq = self._min_stop_interval = 0.
+        self._reset_cmd = self._get_position_cmd = None
+        self._ffi_lib = self._stepqueue = None
         self.print_to_mcu_time = mcu.print_to_mcu_time
+    def set_min_stop_interval(self, min_stop_interval):
+        self._min_stop_interval = min_stop_interval
+    def set_step_distance(self, step_dist):
+        self._step_dist = step_dist
+        self._inv_step_dist = 1. / step_dist
+    def build_config(self):
+        self._mcu_freq = self._mcu.get_mcu_freq()
+        self._velocity_factor = 1. / (self._mcu_freq * self._step_dist)
+        self._accel_factor = 1. / (self._mcu_freq**2 * self._step_dist)
+        max_error = self._mcu.get_max_stepper_error()
+        min_stop_interval = max(0., self._min_stop_interval - max_error)
+        self._mcu.add_config_cmd(
+            "config_stepper oid=%d step_pin=%s dir_pin=%s"
+            " min_stop_interval=TICKS(%.9f) invert_step=%d" % (
+                self._oid, self._step_pin, self._dir_pin,
+                min_stop_interval, self._invert_step))
+        self._mcu.register_stepper(self)
+        step_cmd = self._mcu.lookup_command(
+            "queue_step oid=%c interval=%u count=%hu add=%hi")
+        dir_cmd = self._mcu.lookup_command(
+            "set_next_step_dir oid=%c dir=%c")
+        self._reset_cmd = self._mcu.lookup_command(
+            "reset_step_clock oid=%c clock=%u")
+        self._get_position_cmd = self._mcu.lookup_command(
+            "stepper_get_position oid=%c")
+        ffi_main, self._ffi_lib = chelper.get_ffi()
+        max_error = int(max_error * self._mcu_freq)
+        self._stepqueue = ffi_main.gc(self._ffi_lib.stepcompress_alloc(
+            max_error, step_cmd.msgid, dir_cmd.msgid,
+            self._invert_dir, self._oid),
+                                      self._ffi_lib.stepcompress_free)
     def get_oid(self):
         return self._oid
-    def get_invert_dir(self):
-        return self._invert_dir
     def set_position(self, pos):
-        self._mcu_position_offset += self.commanded_position - pos
-        self.commanded_position = pos
-    def set_mcu_position(self, pos):
-        self._mcu_position_offset = pos - self.commanded_position
+        if pos >= 0.:
+            steppos = int(pos * self._inv_step_dist + 0.5)
+        else:
+            steppos = int(pos * self._inv_step_dist - 0.5)
+        self._mcu_position_offset += self._commanded_pos - steppos
+        self._commanded_pos = steppos
+    def get_commanded_position(self):
+        return self._commanded_pos * self._step_dist
     def get_mcu_position(self):
-        return self.commanded_position + self._mcu_position_offset
-    def note_stepper_stop(self):
-        self.ffi_lib.stepcompress_reset(self._stepqueue, 0)
+        return self._commanded_pos + self._mcu_position_offset
+    def note_homing_start(self, homing_clock):
+        ret = self._ffi_lib.stepcompress_set_homing(
+            self._stepqueue, homing_clock)
+        if ret:
+            raise error("Internal error in stepcompress")
+    def note_homing_finalized(self):
+        ret = self._ffi_lib.stepcompress_set_homing(self._stepqueue, 0)
+        if ret:
+            raise error("Internal error in stepcompress")
+        ret = self._ffi_lib.stepcompress_reset(self._stepqueue, 0)
+        if ret:
+            raise error("Internal error in stepcompress")
+    def note_homing_triggered(self):
+        params = self._mcu.serial.send_with_response(
+            self._get_position_cmd.encode(self._oid),
+            'stepper_position', self._oid)
+        pos = params['pos']
+        if self._invert_dir:
+            pos = -pos
+        self._mcu_position_offset = pos - self._commanded_pos
     def reset_step_clock(self, mcu_time):
         clock = int(mcu_time * self._mcu_freq)
-        self.ffi_lib.stepcompress_reset(self._stepqueue, clock)
+        ret = self._ffi_lib.stepcompress_reset(self._stepqueue, clock)
+        if ret:
+            raise error("Internal error in stepcompress")
         data = (self._reset_cmd.msgid, self._oid, clock & 0xffffffff)
-        self.ffi_lib.stepcompress_queue_msg(self._stepqueue, data, len(data))
+        ret = self._ffi_lib.stepcompress_queue_msg(
+            self._stepqueue, data, len(data))
+        if ret:
+            raise error("Internal error in stepcompress")
     def step(self, mcu_time, sdir):
         clock = mcu_time * self._mcu_freq
-        self.ffi_lib.stepcompress_push(self._stepqueue, clock, sdir)
+        ret = self._ffi_lib.stepcompress_push(self._stepqueue, clock, sdir)
+        if ret:
+            raise error("Internal error in stepcompress")
         if sdir:
-            self.commanded_position += 1
+            self._commanded_pos += 1
         else:
-            self.commanded_position -= 1
-    def step_sqrt(self, mcu_time, steps, step_offset, sqrt_offset, factor):
-        clock = mcu_time * self._mcu_freq
-        mcu_freq2 = self._mcu_freq**2
-        count = self.ffi_lib.stepcompress_push_sqrt(
-            self._stepqueue, steps, step_offset, clock
-            , sqrt_offset * mcu_freq2, factor * mcu_freq2)
-        self.commanded_position += count
-        return count
-    def step_factor(self, mcu_time, steps, step_offset, factor):
-        clock = mcu_time * self._mcu_freq
-        count = self.ffi_lib.stepcompress_push_factor(
-            self._stepqueue, steps, step_offset, clock, factor * self._mcu_freq)
-        self.commanded_position += count
-        return count
-    def step_delta_const(self, mcu_time, dist, start_pos
-                         , inv_velocity, step_dist
-                         , height, closestxy_d, closest_height2, movez_r):
-        clock = mcu_time * self._mcu_freq
-        count = self.ffi_lib.stepcompress_push_delta_const(
-            self._stepqueue, clock, dist, start_pos
-            , inv_velocity * self._mcu_freq, step_dist
-            , height, closestxy_d, closest_height2, movez_r)
-        self.commanded_position += count
-        return count
-    def step_delta_accel(self, mcu_time, dist, start_pos
-                         , accel_multiplier, step_dist
-                         , height, closestxy_d, closest_height2, movez_r):
-        clock = mcu_time * self._mcu_freq
-        mcu_freq2 = self._mcu_freq**2
-        count = self.ffi_lib.stepcompress_push_delta_accel(
-            self._stepqueue, clock, dist, start_pos
-            , accel_multiplier * mcu_freq2, step_dist
-            , height, closestxy_d, closest_height2, movez_r)
-        self.commanded_position += count
-        return count
-    def get_errors(self):
-        return self.ffi_lib.stepcompress_get_errors(self._stepqueue)
+            self._commanded_pos -= 1
+    def step_const(self, mcu_time, start_pos, dist, start_v, accel):
+        inv_step_dist = self._inv_step_dist
+        step_offset = self._commanded_pos - start_pos * inv_step_dist
+        count = self._ffi_lib.stepcompress_push_const(
+            self._stepqueue, mcu_time * self._mcu_freq, step_offset,
+            dist * inv_step_dist, start_v * self._velocity_factor,
+            accel * self._accel_factor)
+        if count == STEPCOMPRESS_ERROR_RET:
+            raise error("Internal error in stepcompress")
+        self._commanded_pos += count
+    def step_delta(self, mcu_time, dist, start_v, accel
+                   , height_base, startxy_d, arm_d, movez_r):
+        inv_step_dist = self._inv_step_dist
+        height = self._commanded_pos - height_base * inv_step_dist
+        count = self._ffi_lib.stepcompress_push_delta(
+            self._stepqueue, mcu_time * self._mcu_freq, dist * inv_step_dist,
+            start_v * self._velocity_factor, accel * self._accel_factor,
+            height, startxy_d * inv_step_dist, arm_d * inv_step_dist, movez_r)
+        if count == STEPCOMPRESS_ERROR_RET:
+            raise error("Internal error in stepcompress")
+        self._commanded_pos += count
 
 class MCU_endstop:
     error = error
     RETRY_QUERY = 1.000
-    def __init__(self, mcu, pin, stepper):
+    def __init__(self, mcu, pin):
         self._mcu = mcu
-        self._oid = mcu.create_oid()
-        self._stepper = stepper
-        stepper_oid = stepper.get_oid()
-        pin, pullup, self._invert = parse_pin_extras(pin, can_pullup=True)
+        self._oid = mcu.create_oid(self)
+        self._steppers = []
+        self._pin, self._pullup, self._invert = parse_pin_extras(
+            pin, can_pullup=True)
         self._cmd_queue = mcu.alloc_command_queue()
-        mcu.add_config_cmd(
-            "config_end_stop oid=%d pin=%s pull_up=%d stepper_oid=%d" % (
-                self._oid, pin, pullup, stepper_oid))
-        self._home_cmd = mcu.lookup_command(
-            "end_stop_home oid=%c clock=%u rest_ticks=%u pin_value=%c")
-        mcu.register_msg(self._handle_end_stop_state, "end_stop_state"
-                         , self._oid)
-        self._query_cmd = mcu.lookup_command("end_stop_query oid=%c")
+        self._home_cmd = self._query_cmd = None
         self._homing = False
-        self._min_query_time = 0.
+        self._min_query_time = self._mcu_freq = 0.
         self._next_query_clock = self._home_timeout_clock = 0
-        self._mcu_freq = mcu.get_mcu_freq()
-        self._retry_query_ticks = int(self._mcu_freq * self.RETRY_QUERY)
+        self._retry_query_ticks = 0
         self._last_state = {}
+        mcu.add_init_callback(self._init_callback)
         self.print_to_mcu_time = mcu.print_to_mcu_time
+    def add_stepper(self, stepper):
+        self._steppers.append(stepper)
+    def build_config(self):
+        self._mcu_freq = self._mcu.get_mcu_freq()
+        self._mcu.add_config_cmd(
+            "config_end_stop oid=%d pin=%s pull_up=%d stepper_count=%d" % (
+                self._oid, self._pin, self._pullup, len(self._steppers)))
+        self._retry_query_ticks = int(self._mcu_freq * self.RETRY_QUERY)
+        self._home_cmd = self._mcu.lookup_command(
+            "end_stop_home oid=%c clock=%u rest_ticks=%u pin_value=%c")
+        self._query_cmd = self._mcu.lookup_command("end_stop_query oid=%c")
+        self._mcu.register_msg(self._handle_end_stop_state, "end_stop_state"
+                               , self._oid)
+    def _init_callback(self):
+        set_cmd = self._mcu.lookup_command(
+            "end_stop_set_stepper oid=%c pos=%c stepper_oid=%c")
+        for i, s in enumerate(self._steppers):
+            msg = set_cmd.encode(self._oid, i, s.get_oid())
+            self._mcu.send(msg, cq=self._cmd_queue)
     def home_start(self, mcu_time, rest_time):
         clock = int(mcu_time * self._mcu_freq)
         rest_ticks = int(rest_time * self._mcu_freq)
         self._homing = True
-        self._min_query_time = time.time()
+        self._min_query_time = self._mcu.monotonic()
         self._next_query_clock = clock + self._retry_query_ticks
         msg = self._home_cmd.encode(
             self._oid, clock, rest_ticks, 1 ^ self._invert)
         self._mcu.send(msg, reqclock=clock, cq=self._cmd_queue)
+        for s in self._steppers:
+            s.note_homing_start(clock)
     def home_finalize(self, mcu_time):
-        # XXX - this flushes the serial port of messages ready to be
-        # sent, but doesn't flush messages if they had an unmet minclock
-        self._mcu.serial.send_flush()
-        self._stepper.note_stepper_stop()
+        for s in self._steppers:
+            s.note_homing_finalized()
         self._home_timeout_clock = int(mcu_time * self._mcu_freq)
     def home_wait(self):
-        eventtime = time.time()
+        eventtime = self._mcu.monotonic()
         while self._check_busy(eventtime):
             eventtime = self._mcu.pause(eventtime + 0.1)
     def _handle_end_stop_state(self, params):
@@ -166,10 +208,8 @@ class MCU_endstop:
             if not self._homing:
                 return False
             if not self._last_state.get('homing', 0):
-                pos = self._last_state.get('pos', 0)
-                if self._stepper.get_invert_dir():
-                    pos = -pos
-                self._stepper.set_mcu_position(pos)
+                for s in self._steppers:
+                    s.note_homing_triggered()
                 self._homing = False
                 return False
             if (self._mcu.serial.get_clock(last_sent_time)
@@ -189,10 +229,10 @@ class MCU_endstop:
     def query_endstop(self, mcu_time):
         clock = int(mcu_time * self._mcu_freq)
         self._homing = False
-        self._min_query_time = time.time()
+        self._min_query_time = self._mcu.monotonic()
         self._next_query_clock = clock
     def query_endstop_wait(self):
-        eventtime = time.time()
+        eventtime = self._mcu.monotonic()
         while self._check_busy(eventtime):
             eventtime = self._mcu.pause(eventtime + 0.1)
         return self._last_state.get('pin', self._invert) ^ self._invert
@@ -200,18 +240,22 @@ class MCU_endstop:
 class MCU_digital_out:
     def __init__(self, mcu, pin, max_duration):
         self._mcu = mcu
-        self._oid = mcu.create_oid()
+        self._oid = mcu.create_oid(self)
         pin, pullup, self._invert = parse_pin_extras(pin)
         self._last_clock = 0
         self._last_value = None
-        self._mcu_freq = mcu.get_mcu_freq()
+        self._mcu_freq = 0.
         self._cmd_queue = mcu.alloc_command_queue()
         mcu.add_config_cmd(
             "config_digital_out oid=%d pin=%s default_value=%d"
-            " max_duration=%d" % (self._oid, pin, self._invert, max_duration))
-        self._set_cmd = mcu.lookup_command(
-            "schedule_digital_out oid=%c clock=%u value=%c")
+            " max_duration=TICKS(%f)" % (
+                self._oid, pin, self._invert, max_duration))
+        self._set_cmd = None
         self.print_to_mcu_time = mcu.print_to_mcu_time
+    def build_config(self):
+        self._mcu_freq = self._mcu.get_mcu_freq()
+        self._set_cmd = self._mcu.lookup_command(
+            "schedule_digital_out oid=%c clock=%u value=%c")
     def set_digital(self, mcu_time, value):
         clock = int(mcu_time * self._mcu_freq)
         msg = self._set_cmd.encode(self._oid, clock, value ^ self._invert)
@@ -223,33 +267,46 @@ class MCU_digital_out:
         return self._last_value
     def set_pwm(self, mcu_time, value):
         dval = 0
-        if value > 127:
+        if value >= 0.5:
             dval = 1
         self.set_digital(mcu_time, dval)
 
 class MCU_pwm:
-    def __init__(self, mcu, pin, cycle_ticks, max_duration, hard_pwm=True):
+    PWM_MAX = 255.
+    def __init__(self, mcu, pin, cycle_time, hard_cycle_ticks, max_duration):
         self._mcu = mcu
-        self._oid = mcu.create_oid()
+        self._hard_cycle_ticks = hard_cycle_ticks
+        self._oid = mcu.create_oid(self)
+        pin, pullup, self._invert = parse_pin_extras(pin)
         self._last_clock = 0
-        self._mcu_freq = mcu.get_mcu_freq()
+        self._mcu_freq = 0.
         self._cmd_queue = mcu.alloc_command_queue()
-        if hard_pwm:
+        if hard_cycle_ticks:
             mcu.add_config_cmd(
-                "config_pwm_out oid=%d pin=%s cycle_ticks=%d default_value=0"
-                " max_duration=%d" % (self._oid, pin, cycle_ticks, max_duration))
-            self._set_cmd = mcu.lookup_command(
-                "schedule_pwm_out oid=%c clock=%u value=%c")
+                "config_pwm_out oid=%d pin=%s cycle_ticks=%d default_value=%d"
+                " max_duration=TICKS(%f)" % (
+                    self._oid, pin, hard_cycle_ticks, self._invert,
+                    max_duration))
         else:
             mcu.add_config_cmd(
-                "config_soft_pwm_out oid=%d pin=%s cycle_ticks=%d"
-                " default_value=0 max_duration=%d" % (
-                    self._oid, pin, cycle_ticks, max_duration))
-            self._set_cmd = mcu.lookup_command(
-                "schedule_soft_pwm_out oid=%c clock=%u value=%c")
+                "config_soft_pwm_out oid=%d pin=%s cycle_ticks=TICKS(%f)"
+                " default_value=%d max_duration=TICKS(%f)" % (
+                    self._oid, pin, cycle_time, self._invert, max_duration))
+        self._set_cmd = None
         self.print_to_mcu_time = mcu.print_to_mcu_time
+    def build_config(self):
+        self._mcu_freq = self._mcu.get_mcu_freq()
+        if self._hard_cycle_ticks:
+            self._set_cmd = self._mcu.lookup_command(
+                "schedule_pwm_out oid=%c clock=%u value=%c")
+        else:
+            self._set_cmd = self._mcu.lookup_command(
+                "schedule_soft_pwm_out oid=%c clock=%u value=%c")
     def set_pwm(self, mcu_time, value):
         clock = int(mcu_time * self._mcu_freq)
+        if self._invert:
+            value = 1. - value
+        value = int(value * self.PWM_MAX + 0.5)
         msg = self._set_cmd.encode(self._oid, clock, value)
         self._mcu.send(msg, minclock=self._last_clock, reqclock=clock
                       , cq=self._cmd_queue)
@@ -258,41 +315,46 @@ class MCU_pwm:
 class MCU_adc:
     def __init__(self, mcu, pin):
         self._mcu = mcu
-        self._oid = mcu.create_oid()
-        self._min_sample = 0
-        self._max_sample = 0xffff
-        self._sample_ticks = 0
-        self._sample_count = 1
+        self._oid = mcu.create_oid(self)
+        self._min_sample = self._max_sample = 0.
+        self._sample_time = self._report_time = 0.
+        self._sample_count = 0
         self._report_clock = 0
         self._callback = None
         self._inv_max_adc = 0.
-        self._mcu_freq = mcu.get_mcu_freq()
+        self._mcu_freq = 0.
         self._cmd_queue = mcu.alloc_command_queue()
         mcu.add_config_cmd("config_analog_in oid=%d pin=%s" % (self._oid, pin))
+        self._query_cmd = None
         mcu.add_init_callback(self._init_callback)
-        mcu.register_msg(self._handle_analog_in_state, "analog_in_state"
-                         , self._oid)
-        self._query_cmd = mcu.lookup_command(
+        self._query_cmd = None
+    def build_config(self):
+        self._mcu_freq = self._mcu.get_mcu_freq()
+        self._query_cmd = self._mcu.lookup_command(
             "query_analog_in oid=%c clock=%u sample_ticks=%u sample_count=%c"
             " rest_ticks=%u min_value=%hu max_value=%hu")
-    def set_minmax(self, sample_time, sample_count, minval=None, maxval=None):
-        self._sample_ticks = int(sample_time * self._mcu_freq)
+    def set_minmax(self, sample_time, sample_count, minval=0., maxval=1.):
+        self._sample_time = sample_time
         self._sample_count = sample_count
-        if minval is None:
-            minval = 0
-        if maxval is None:
-            maxval = 0xffff
-        mcu_adc_max = float(self._mcu.serial.msgparser.config["ADC_MAX"])
-        max_adc = sample_count * mcu_adc_max
-        self._min_sample = int(minval * max_adc)
-        self._max_sample = min(0xffff, int(math.ceil(maxval * max_adc)))
-        self._inv_max_adc = 1.0 / max_adc
+        self._min_sample = minval
+        self._max_sample = maxval
     def _init_callback(self):
+        if not self._sample_count:
+            return
         last_clock, last_clock_time = self._mcu.get_last_clock()
         clock = last_clock + int(self._mcu_freq * (1.0 + self._oid * 0.01)) # XXX
+        sample_ticks = int(self._sample_time * self._mcu_freq)
+        mcu_adc_max = self._mcu.serial.msgparser.get_constant_float("ADC_MAX")
+        max_adc = self._sample_count * mcu_adc_max
+        self._inv_max_adc = 1.0 / max_adc
+        self._report_clock = int(self._report_time * self._mcu_freq)
+        self._mcu.register_msg(self._handle_analog_in_state, "analog_in_state"
+                               , self._oid)
+        min_sample = int(self._min_sample * max_adc)
+        max_sample = min(0xffff, int(math.ceil(self._max_sample * max_adc)))
         msg = self._query_cmd.encode(
-            self._oid, clock, self._sample_ticks, self._sample_count
-            , self._report_clock, self._min_sample, self._max_sample)
+            self._oid, clock, sample_ticks, self._sample_count
+            , self._report_clock, min_sample, max_sample)
         self._mcu.send(msg, reqclock=clock, cq=self._cmd_queue)
     def _handle_analog_in_state(self, params):
         last_value = params['value'] * self._inv_max_adc
@@ -301,7 +363,7 @@ class MCU_adc:
         if self._callback is not None:
             self._callback(last_read_time, last_value)
     def set_adc_callback(self, report_time, callback):
-        self._report_clock = int(report_time * self._mcu_freq)
+        self._report_time = report_time
         self._callback = callback
 
 class MCU:
@@ -309,60 +371,91 @@ class MCU:
     COMM_TIMEOUT = 3.5
     def __init__(self, printer, config):
         self._printer = printer
-        self._config = config
         # Serial port
-        baud = config.getint('baud', 115200)
-        serialport = config.get('serial', '/dev/ttyS0')
-        self.serial = serialhdl.SerialReader(printer.reactor, serialport, baud)
+        baud = config.getint('baud', 250000)
+        self._serialport = config.get('serial', '/dev/ttyS0')
+        self.serial = serialhdl.SerialReader(
+            printer.reactor, self._serialport, baud)
         self.is_shutdown = False
+        self._shutdown_msg = ""
         self._is_fileoutput = False
         self._timeout_timer = printer.reactor.register_timer(
             self.timeout_handler)
+        rmethods = {m: m for m in ['arduino', 'command', 'rpi_usb']}
+        self._restart_method = config.getchoice(
+            'restart_method', rmethods, 'arduino')
         # Config building
-        self._emergency_stop_cmd = self._clear_shutdown_cmd = None
-        self._num_oids = 0
+        if printer.bglogger is not None:
+            printer.bglogger.set_rollover_info("mcu", None)
+        self._config_error = config.error
+        self._emergency_stop_cmd = self._reset_cmd = None
+        self._oids = []
         self._config_cmds = []
         self._config_crc = None
         self._init_callbacks = []
+        self._pin_map = config.get('pin_map', None)
+        self._custom = config.get('custom', '')
         # Move command queuing
-        ffi_main, self.ffi_lib = chelper.get_ffi()
+        ffi_main, self._ffi_lib = chelper.get_ffi()
+        self._max_stepper_error = config.getfloat(
+            'max_stepper_error', 0.000025, minval=0.)
         self._steppers = []
         self._steppersync = None
         # Print time to clock epoch calculations
         self._print_start_time = 0.
         self._mcu_freq = 0.
         # Stats
+        self._stats_sumsq_base = 0.
         self._mcu_tick_avg = 0.
         self._mcu_tick_stddev = 0.
     def handle_mcu_stats(self, params):
-        logging.debug("mcu stats: %s" % (params,))
         count = params['count']
         tick_sum = params['sum']
         c = 1.0 / (count * self._mcu_freq)
         self._mcu_tick_avg = tick_sum * c
-        tick_sumsq = params['sumsq']
-        tick_sumavgsq = ((tick_sum // (256*count)) * count)**2
-        self._mcu_tick_stddev = c * 256. * math.sqrt(
-            count * tick_sumsq - tick_sumavgsq)
+        tick_sumsq = params['sumsq'] * self._stats_sumsq_base
+        self._mcu_tick_stddev = c * math.sqrt(count*tick_sumsq - tick_sum**2)
     def handle_shutdown(self, params):
         if self.is_shutdown:
             return
         self.is_shutdown = True
-        logging.info("%s: %s" % (params['#name'], params['#msg']))
+        self._shutdown_msg = params['#msg']
+        logging.info("%s: %s" % (params['#name'], self._shutdown_msg))
+        pst = self._print_start_time
+        logging.info("Clock last synchronized at %.6f (%d)" % (
+            pst, int(pst * self._mcu_freq)))
         self.serial.dump_debug()
-        self._printer.note_shutdown(params['#msg'])
+        self._printer.note_shutdown(self._shutdown_msg)
     # Connection phase
+    def _check_restart(self, reason):
+        if self._printer.get_startup_state() == 'firmware_restart':
+            return
+        logging.info("Attempting automated firmware restart: %s" % (reason,))
+        self._printer.request_exit('firmware_restart')
+        self._printer.reactor.pause(self._printer.reactor.monotonic() + 2.000)
+        raise error("Attempt firmware restart failed")
     def connect(self):
         if not self._is_fileoutput:
+            if (self._restart_method == 'rpi_usb'
+                and not os.path.exists(self._serialport)):
+                # Try toggling usb power
+                self._check_restart("enable power")
             self.serial.connect()
             self._printer.reactor.update_timer(
-                self._timeout_timer, time.time() + self.COMM_TIMEOUT)
-        self._mcu_freq = float(self.serial.msgparser.config['CLOCK_FREQ'])
+                self._timeout_timer, self.monotonic() + self.COMM_TIMEOUT)
+        self._mcu_freq = self.serial.msgparser.get_constant_float('CLOCK_FREQ')
+        self._stats_sumsq_base = self.serial.msgparser.get_constant_float(
+            'STATS_SUMSQ_BASE')
         self._emergency_stop_cmd = self.lookup_command("emergency_stop")
-        self._clear_shutdown_cmd = self.lookup_command("clear_shutdown")
+        try:
+            self._reset_cmd = self.lookup_command("reset")
+        except self.serial.msgparser.error, e:
+            pass
         self.register_msg(self.handle_shutdown, 'shutdown')
         self.register_msg(self.handle_shutdown, 'is_shutdown')
         self.register_msg(self.handle_mcu_stats, 'stats')
+        self._build_config()
+        self._send_config()
     def connect_file(self, debugoutput, dictionary, pace=False):
         self._is_fileoutput = True
         self.serial.connect_file(debugoutput, dictionary)
@@ -370,7 +463,7 @@ class MCU:
             def dummy_set_print_start_time(eventtime):
                 pass
             def dummy_get_print_buffer_time(eventtime, last_move_end):
-                return 0.250
+                return 1.250
             self.set_print_start_time = dummy_set_print_start_time
             self.get_print_buffer_time = dummy_get_print_buffer_time
     def timeout_handler(self, eventtime):
@@ -385,29 +478,45 @@ class MCU:
     def disconnect(self):
         self.serial.disconnect()
         if self._steppersync is not None:
-            self.ffi_lib.steppersync_free(self._steppersync)
+            self._ffi_lib.steppersync_free(self._steppersync)
             self._steppersync = None
     def stats(self, eventtime):
-        stats = self.serial.stats(eventtime)
-        stats += " mcu_task_avg=%.06f mcu_task_stddev=%.06f" % (
+        return "%s mcu_task_avg=%.06f mcu_task_stddev=%.06f" % (
+            self.serial.stats(eventtime),
             self._mcu_tick_avg, self._mcu_tick_stddev)
-        err = 0
-        for s in self._steppers:
-            err += s.get_errors()
-        if err:
-            stats += " step_errors=%d" % (err,)
-        return stats
     def force_shutdown(self):
         self.send(self._emergency_stop_cmd.encode())
-    def clear_shutdown(self):
-        logging.info("Sending clear_shutdown command")
-        self.send(self._clear_shutdown_cmd.encode())
+    def microcontroller_restart(self):
+        reactor = self._printer.reactor
+        if self._restart_method == 'rpi_usb':
+            logging.info("Attempting a microcontroller reset via rpi usb power")
+            self.disconnect()
+            chelper.run_hub_ctrl(0)
+            reactor.pause(reactor.monotonic() + 2.000)
+            chelper.run_hub_ctrl(1)
+            return
+        if self._restart_method == 'command':
+            last_clock, last_clock_time = self.serial.get_last_clock()
+            eventtime = reactor.monotonic()
+            if (self._reset_cmd is None
+                or eventtime > last_clock_time + self.COMM_TIMEOUT):
+                logging.info("Unable to issue reset command")
+                return
+            # Attempt reset via command
+            logging.info("Attempting a microcontroller reset command")
+            self.send(self._reset_cmd.encode())
+            reactor.pause(reactor.monotonic() + 0.015)
+            self.disconnect()
+            return
+        # Attempt reset via arduino mechanism
+        logging.info("Attempting a microcontroller reset")
+        self.disconnect()
+        serialhdl.arduino_reset(self._serialport, reactor)
     def is_fileoutput(self):
         return self._is_fileoutput
     # Configuration phase
     def _add_custom(self):
-        data = self._config.get('custom', '')
-        for line in data.split('\n'):
+        for line in self._custom.split('\n'):
             line = line.strip()
             cpos = line.find('#')
             if cpos >= 0:
@@ -415,33 +524,30 @@ class MCU:
             if not line:
                 continue
             self.add_config_cmd(line)
-    def build_config(self):
+    def _build_config(self):
         # Build config commands
+        for oid in self._oids:
+            oid.build_config()
         self._add_custom()
         self._config_cmds.insert(0, "allocate_oids count=%d" % (
-            self._num_oids,))
+            len(self._oids),))
 
         # Resolve pin names
-        mcu = self.serial.msgparser.config['MCU']
-        pin_map = self._config.get('pin_map', None)
-        if pin_map is None:
-            pnames = pins.mcu_to_pins(mcu)
-        else:
-            pnames = pins.map_pins(pin_map, mcu)
+        mcu = self.serial.msgparser.get_constant('MCU')
+        pnames = pins.get_pin_map(mcu, self._pin_map)
         updated_cmds = []
         for cmd in self._config_cmds:
             try:
-                updated_cmds.append(pins.update_command(cmd, pnames))
+                updated_cmds.append(pins.update_command(
+                    cmd, self._mcu_freq, pnames))
             except:
-                raise self._config.error("Unable to translate pin name: %s" % (
+                raise self._config_error("Unable to translate pin name: %s" % (
                     cmd,))
         self._config_cmds = updated_cmds
 
         # Calculate config CRC
         self._config_crc = zlib.crc32('\n'.join(self._config_cmds)) & 0xffffffff
         self.add_config_cmd("finalize_config crc=%d" % (self._config_crc,))
-
-        self._send_config()
     def _send_config(self):
         msg = self.create_command("get_config")
         if self._is_fileoutput:
@@ -450,25 +556,45 @@ class MCU:
         else:
             config_params = self.serial.send_with_response(msg, 'config')
         if not config_params['is_config']:
+            if self._restart_method == 'rpi_usb':
+                # Only configure mcu after usb power reset
+                self._check_restart("full reset before config")
             # Send config commands
+            logging.info("Sending printer configuration...")
             for c in self._config_cmds:
                 self.send(self.create_command(c))
             if not self._is_fileoutput:
                 config_params = self.serial.send_with_response(msg, 'config')
+                if not config_params['is_config']:
+                    if self.is_shutdown:
+                        raise error("Firmware error during config: %s" % (
+                            self._shutdown_msg,))
+                    raise error("Unable to configure printer")
+        elif self._printer.get_startup_state() == 'firmware_restart':
+            raise error("Failed automated reset of micro-controller")
         if self._config_crc != config_params['crc']:
+            self._check_restart("CRC mismatch")
             raise error("Printer CRC does not match config")
-        logging.info("Configured")
+        move_count = config_params['move_count']
+        logging.info("Configured (%d moves)" % (move_count,))
+        if self._printer.bglogger is not None:
+            msgparser = self.serial.msgparser
+            info = [
+                "Configured (%d moves)" % (move_count,),
+                "Loaded %d commands (%s)" % (
+                    len(msgparser.messages_by_id), msgparser.version),
+                "MCU config: %s" % (" ".join(
+                    ["%s=%s" % (k, v) for k, v in msgparser.config.items()]))]
+            self._printer.bglogger.set_rollover_info("mcu", "\n".join(info))
         stepqueues = tuple(s._stepqueue for s in self._steppers)
-        self._steppersync = self.ffi_lib.steppersync_alloc(
-            self.serial.serialqueue, stepqueues, len(stepqueues),
-            config_params['move_count'])
+        self._steppersync = self._ffi_lib.steppersync_alloc(
+            self.serial.serialqueue, stepqueues, len(stepqueues), move_count)
         for cb in self._init_callbacks:
             cb()
     # Config creation helpers
-    def create_oid(self):
-        oid = self._num_oids
-        self._num_oids += 1
-        return oid
+    def create_oid(self, oid):
+        self._oids.append(oid)
+        return len(self._oids) - 1
     def add_config_cmd(self, cmd):
         self._config_cmds.append(cmd)
     def add_init_callback(self, callback):
@@ -484,26 +610,24 @@ class MCU:
     def create_command(self, msg):
         return self.serial.msgparser.create_command(msg)
     # Wrappers for mcu object creation
-    def create_stepper(self, step_pin, dir_pin, min_stop_interval, max_error):
-        return MCU_stepper(self, step_pin, dir_pin, min_stop_interval, max_error)
-    def create_endstop(self, pin, stepper):
-        return MCU_endstop(self, pin, stepper)
+    def create_stepper(self, step_pin, dir_pin):
+        return MCU_stepper(self, step_pin, dir_pin)
+    def create_endstop(self, pin):
+        return MCU_endstop(self, pin)
     def create_digital_out(self, pin, max_duration=2.):
-        max_duration = int(max_duration * self._mcu_freq)
         return MCU_digital_out(self, pin, max_duration)
-    def create_pwm(self, pin, hard_cycle_ticks, max_duration=2.):
-        max_duration = int(max_duration * self._mcu_freq)
-        if hard_cycle_ticks:
-            return MCU_pwm(self, pin, hard_cycle_ticks, max_duration)
+    def create_pwm(self, pin, cycle_time, hard_cycle_ticks=0, max_duration=2.):
         if hard_cycle_ticks < 0:
             return MCU_digital_out(self, pin, max_duration)
-        cycle_ticks = int(self._mcu_freq / 10.)
-        return MCU_pwm(self, pin, cycle_ticks, max_duration, hard_pwm=False)
+        return MCU_pwm(self, pin, cycle_time, hard_cycle_ticks, max_duration)
     def create_adc(self, pin):
         return MCU_adc(self, pin)
     # Clock syncing
     def set_print_start_time(self, eventtime):
-        est_mcu_time = self.serial.get_clock(eventtime) / self._mcu_freq
+        clock = self.serial.get_clock(eventtime)
+        logging.debug("Synchronizing mcu clock at %.6f to %d" % (
+            eventtime, clock))
+        est_mcu_time = clock / self._mcu_freq
         self._print_start_time = est_mcu_time
     def get_print_buffer_time(self, eventtime, print_time):
         if self.is_shutdown:
@@ -517,14 +641,22 @@ class MCU:
         return self._mcu_freq
     def get_last_clock(self):
         return self.serial.get_last_clock()
+    def get_max_stepper_error(self):
+        return self._max_stepper_error
     # Move command queuing
     def send(self, cmd, minclock=0, reqclock=0, cq=None):
         self.serial.send(cmd, minclock, reqclock, cq=cq)
     def flush_moves(self, print_time):
+        if self._steppersync is None:
+            return
         mcu_time = print_time + self._print_start_time
         clock = int(mcu_time * self._mcu_freq)
-        self.ffi_lib.steppersync_flush(self._steppersync, clock)
+        ret = self._ffi_lib.steppersync_flush(self._steppersync, clock)
+        if ret:
+            raise error("Internal error in stepcompress")
     def pause(self, waketime):
         return self._printer.reactor.pause(waketime)
+    def monotonic(self):
+        return self._printer.reactor.monotonic()
     def __del__(self):
         self.disconnect()

klippy/msgproto.py

@@ -1,6 +1,6 @@
 # Protocol definitions for firmware communication
 #
-# Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import json, zlib, logging
@@ -106,8 +106,8 @@ class MessageFormat:
         self.name = parts[0]
         argparts = [arg.split('=') for arg in parts[1:]]
         self.param_types = [MessageTypes[fmt] for name, fmt in argparts]
-        self.param_names = [name for name, fmt in argparts]
-        self.name_to_type = dict(zip(self.param_names, self.param_types))
+        self.param_names = [(name, MessageTypes[fmt]) for name, fmt in argparts]
+        self.name_to_type = dict(self.param_names)
     def encode(self, *params):
         out = []
         out.append(self.msgid)
@@ -117,26 +117,24 @@ class MessageFormat:
     def encode_by_name(self, **params):
         out = []
         out.append(self.msgid)
-        for name, t in zip(self.param_names, self.param_types):
+        for name, t in self.param_names:
             t.encode(out, params[name])
         return out
     def parse(self, s, pos):
         pos += 1
         out = {}
-        for t, name in zip(self.param_types, self.param_names):
+        for name, t in self.param_names:
             v, pos = t.parse(s, pos)
             out[name] = v
         return out, pos
-    def dump(self, s, pos):
-        pos += 1
+    def format_params(self, params):
         out = []
-        for t in self.param_types:
-            v, pos = t.parse(s, pos)
+        for name, t in self.param_names:
+            v = params[name]
             if not t.is_int:
                 v = repr(v)
             out.append(v)
-        outmsg = self.debugformat % tuple(out)
-        return outmsg, pos
+        return self.debugformat % tuple(out)
 
 class OutputFormat:
     name = '#output'
@@ -164,17 +162,13 @@ class OutputFormat:
         out = []
         for t in self.param_types:
             v, pos = t.parse(s, pos)
+            if not t.is_int:
+                v = repr(v)
             out.append(v)
         outmsg = self.debugformat % tuple(out)
         return {'#msg': outmsg}, pos
-    def dump(self, s, pos):
-        pos += 1
-        out = []
-        for t in self.param_types:
-            v, pos = t.parse(s, pos)
-            out.append(v)
-        outmsg = self.debugformat % tuple(out)
-        return outmsg, pos
+    def format_params(self, params):
+        return "#output %s" % (params['#msg'],)
 
 class UnknownFormat:
     name = '#unknown'
@@ -182,8 +176,11 @@ class UnknownFormat:
         msgid = s[pos]
         msg = str(bytearray(s))
         return {'#msgid': msgid, '#msg': msg}, len(s)-MESSAGE_TRAILER_SIZE
+    def format_params(self, params):
+        return "#unknown %s" % (repr(params['#msg']),)
 
 class MessageParser:
+    error = error
     def __init__(self):
         self.unknown = UnknownFormat()
         self.messages_by_id = {}
@@ -220,11 +217,20 @@ class MessageParser:
         while 1:
             msgid = s[pos]
             mid = self.messages_by_id.get(msgid, self.unknown)
-            params, pos = mid.dump(s, pos)
-            out.append("%s" % (params,))
+            params, pos = mid.parse(s, pos)
+            out.append(mid.format_params(params))
             if pos >= len(s)-MESSAGE_TRAILER_SIZE:
                 break
         return out
+    def format_params(self, params):
+        name = params.get('#name')
+        mid = self.messages_by_name.get(name)
+        if mid is not None:
+            return mid.format_params(params)
+        msg = params.get('#msg')
+        if msg is not None:
+            return "%s %s" % (name, msg)
+        return str(params)
     def parse(self, s):
         msgid = s[MESSAGE_HEADER_SIZE]
         mid = self.messages_by_id.get(msgid, self.unknown)
@@ -308,3 +314,15 @@ class MessageParser:
         self.static_strings = data.get('static_strings', [])
         self.config.update(data.get('config', {}))
         self.version = data.get('version', '')
+    def get_constant(self, name):
+        try:
+            return self.config[name]
+        except KeyError:
+            raise error("Firmware constant '%s' not found" % (name,))
+    def get_constant_float(self, name):
+        try:
+            return float(self.config[name])
+        except ValueError:
+            raise error("Firmware constant '%s' not a float" % (name,))
+        except KeyError:
+            raise error("Firmware constant '%s' not found" % (name,))

klippy/pins.py

@@ -16,25 +16,13 @@ def port_pins(port_count, bit_count=8):
             pins['P%c%d' % (portchr, portbit)] = port * bit_count + portbit
     return pins
 
-PINS_atmega164 = port_pins(4)
-PINS_atmega1280 = port_pins(12)
-
 MCU_PINS = {
-    "atmega168": PINS_atmega164, "atmega644p": PINS_atmega164,
+    "atmega168": port_pins(4), "atmega644p": port_pins(4),
     "at90usb1286": port_pins(5),
-    "atmega1280": PINS_atmega1280, "atmega2560": PINS_atmega1280,
+    "atmega1280": port_pins(12), "atmega2560": port_pins(12),
     "sam3x8e": port_pins(4, 32)
 }
 
-def mcu_to_pins(mcu):
-    return MCU_PINS.get(mcu, {})
-
-re_pin = re.compile(r'(?P<prefix>[ _]pin=)(?P<name>[^ ]*)')
-def update_command(cmd, pmap):
-    def fixup(m):
-        return m.group('prefix') + str(pmap[m.group('name')])
-    return re_pin.sub(fixup, cmd)
-
 
 ######################################################################
 # Arduino mappings
@@ -96,12 +84,28 @@ Arduino_from_mcu = {
     "sam3x8e": (Arduino_Due, Arduino_Due_analog),
 }
 
-def map_pins(name, mcu):
+
+######################################################################
+# External commands
+######################################################################
+
+# Obtains the pin mappings
+def get_pin_map(mcu, mapping_name=None):
     pins = MCU_PINS.get(mcu, {})
-    if name == 'arduino':
+    if mapping_name == 'arduino':
         dpins, apins = Arduino_from_mcu.get(mcu, [])
         for i in range(len(dpins)):
             pins['ar' + str(i)] = pins[dpins[i]]
         for i in range(len(apins)):
             pins['analog%d' % (i,)] = pins[apins[i]]
     return pins
+
+# Translate pin names and tick times in a firmware command
+re_pin = re.compile(r'(?P<prefix>[ _]pin=)(?P<name>[^ ]*)')
+re_ticks = re.compile(r'TICKS\((?P<ticks>[^)]*)\)')
+def update_command(cmd, mcu_freq, pmap):
+    def pin_fixup(m):
+        return m.group('prefix') + str(pmap[m.group('name')])
+    def ticks_fixup(m):
+        return str(int(mcu_freq * float(m.group('ticks'))))
+    return re_ticks.sub(ticks_fixup, re_pin.sub(pin_fixup, cmd))

klippy/pyhelper.c

@@ -9,17 +9,20 @@
 #include <stdint.h> // uint8_t
 #include <stdio.h> // fprintf
 #include <string.h> // strerror
-#include <sys/time.h> // gettimeofday
 #include <time.h> // struct timespec
-#include "pyhelper.h" // get_time
+#include "pyhelper.h" // get_monotonic
 
-// Return the current system time as a double
+// Return the monotonic system time as a double
 double
-get_time(void)
+get_monotonic(void)
 {
-    struct timeval tv;
-    gettimeofday(&tv, NULL);
-    return (double)tv.tv_sec + (double)tv.tv_usec / 1000000.;
+    struct timespec ts;
+    int ret = clock_gettime(CLOCK_MONOTONIC, &ts);
+    if (ret) {
+        report_errno("clock_gettime", ret);
+        return 0.;
+    }
+    return (double)ts.tv_sec + (double)ts.tv_nsec * .000000001;
 }
 
 // Fill a 'struct timespec' with a system time stored in a double

klippy/pyhelper.h

@@ -1,7 +1,10 @@
 #ifndef PYHELPER_H
 #define PYHELPER_H
 
-double get_time(void);
+#define likely(x)       __builtin_expect(!!(x), 1)
+#define unlikely(x)     __builtin_expect(!!(x), 0)
+
+double get_monotonic(void);
 struct timespec fill_time(double time);
 void set_python_logging_callback(void (*func)(const char *));
 void errorf(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));

klippy/queuelogger.py

@@ -1,9 +1,9 @@
 # Code to implement asynchronous logging from a background thread
 #
-# Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import logging, threading, Queue
+import logging, logging.handlers, threading, Queue, time
 
 # Class to forward all messages through a queue to a background thread
 class QueueHandler(logging.Handler):
@@ -21,27 +21,39 @@ class QueueHandler(logging.Handler):
             self.handleError(record)
 
 # Class to poll a queue in a background thread and log each message
-class QueueListener(object):
-    def __init__(self, handler):
-        self.handler = handler
-        self.queue = Queue.Queue()
-        self.thread = threading.Thread(target=self._bg_thread)
-        self.thread.start()
+class QueueListener(logging.handlers.TimedRotatingFileHandler):
+    def __init__(self, filename):
+        logging.handlers.TimedRotatingFileHandler.__init__(
+            self, filename, when='midnight', backupCount=5)
+        self.bg_queue = Queue.Queue()
+        self.bg_thread = threading.Thread(target=self._bg_thread)
+        self.bg_thread.start()
+        self.rollover_info = {}
     def _bg_thread(self):
         while 1:
-            record = self.queue.get(True)
+            record = self.bg_queue.get(True)
             if record is None:
                 break
-            self.handler.handle(record)
+            self.handle(record)
     def stop(self):
-        self.queue.put_nowait(None)
-        self.thread.join()
+        self.bg_queue.put_nowait(None)
+        self.bg_thread.join()
+    def set_rollover_info(self, name, info):
+        self.rollover_info[name] = info
+    def doRollover(self):
+        logging.handlers.TimedRotatingFileHandler.doRollover(self)
+        lines = [self.rollover_info[name]
+                 for name in sorted(self.rollover_info)
+                 if self.rollover_info[name]]
+        lines.append(
+            "=============== Log rollover at %s ===============" % (
+                time.asctime(),))
+        self.emit(logging.makeLogRecord(
+            {'msg': "\n".join(lines), 'level': logging.INFO}))
 
 def setup_bg_logging(filename, debuglevel):
-    logoutput = open(filename, 'wb')
-    handler = logging.StreamHandler(logoutput)
-    ql = QueueListener(handler)
-    qh = QueueHandler(ql.queue)
+    ql = QueueListener(filename)
+    qh = QueueHandler(ql.bg_queue)
     root = logging.getLogger()
     root.addHandler(qh)
     root.setLevel(debuglevel)

klippy/reactor.py

@@ -1,10 +1,11 @@
 # File descriptor and timer event helper
 #
-# Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import select, time, math
+import select, math, time
 import greenlet
+import chelper
 
 class ReactorTimer:
     def __init__(self, callback, waketime):
@@ -33,6 +34,7 @@ class SelectReactor:
         self._process = False
         self._g_dispatch = None
         self._greenlets = []
+        self.monotonic = chelper.get_ffi()[1].get_monotonic
     # Timers
     def _note_time(self, t):
         nexttime = t.waketime
@@ -67,11 +69,19 @@ class SelectReactor:
             self._note_time(t)
         if eventtime >= self._next_timer:
             return 0.
-        return min(1., max(.001, self._next_timer - time.time()))
+        return min(1., max(.001, self._next_timer - self.monotonic()))
     # Greenlets
+    def _sys_pause(self, waketime):
+        # Pause using system sleep for when reactor not running
+        delay = waketime - self.monotonic()
+        if delay > 0.:
+            time.sleep(delay)
+        return self.monotonic()
     def pause(self, waketime):
         g = greenlet.getcurrent()
         if g is not self._g_dispatch:
+            if self._g_dispatch is None:
+                return self._sys_pause(waketime)
             return self._g_dispatch.switch(waketime)
         if self._greenlets:
             g_next = self._greenlets.pop()
@@ -95,20 +105,21 @@ class SelectReactor:
         self._fds.pop(self._fds.index(handler))
     # Main loop
     def _dispatch_loop(self):
-        self._process = True
         self._g_dispatch = g_dispatch = greenlet.getcurrent()
-        eventtime = time.time()
+        eventtime = self.monotonic()
         while self._process:
             timeout = self._check_timers(eventtime)
             res = select.select(self._fds, [], [], timeout)
-            eventtime = time.time()
+            eventtime = self.monotonic()
             for fd in res[0]:
                 fd.callback(eventtime)
                 if g_dispatch is not self._g_dispatch:
                     self._end_greenlet(g_dispatch)
+                    eventtime = self.monotonic()
                     break
         self._g_dispatch = None
     def run(self):
+        self._process = True
         g_next = ReactorGreenlet(run=self._dispatch_loop)
         g_next.switch()
     def end(self):
@@ -134,17 +145,17 @@ class PollReactor(SelectReactor):
         self._fds = fds
     # Main loop
     def _dispatch_loop(self):
-        self._process = True
         self._g_dispatch = g_dispatch = greenlet.getcurrent()
-        eventtime = time.time()
+        eventtime = self.monotonic()
         while self._process:
-            timeout = int(math.ceil(self._check_timers(eventtime) * 1000.))
-            res = self._poll.poll(timeout)
-            eventtime = time.time()
+            timeout = self._check_timers(eventtime)
+            res = self._poll.poll(int(math.ceil(timeout * 1000.)))
+            eventtime = self.monotonic()
             for fd, event in res:
                 self._fds[fd](eventtime)
                 if g_dispatch is not self._g_dispatch:
                     self._end_greenlet(g_dispatch)
+                    eventtime = self.monotonic()
                     break
         self._g_dispatch = None
 
@@ -168,17 +179,17 @@ class EPollReactor(SelectReactor):
         self._fds = fds
     # Main loop
     def _dispatch_loop(self):
-        self._process = True
         self._g_dispatch = g_dispatch = greenlet.getcurrent()
-        eventtime = time.time()
+        eventtime = self.monotonic()
         while self._process:
             timeout = self._check_timers(eventtime)
             res = self._epoll.poll(timeout)
-            eventtime = time.time()
+            eventtime = self.monotonic()
             for fd, event in res:
                 self._fds[fd](eventtime)
                 if g_dispatch is not self._g_dispatch:
                     self._end_greenlet(g_dispatch)
+                    eventtime = self.monotonic()
                     break
         self._g_dispatch = None
 

klippy/serialhdl.py

@@ -3,11 +3,14 @@
 # Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import time, logging, threading
+import logging, threading
 import serial
 
 import msgproto, chelper, util
 
+class error(Exception):
+    pass
+
 class SerialReader:
     BITS_PER_BYTE = 10.
     def __init__(self, reactor, serialport, baud):
@@ -30,8 +33,7 @@ class SerialReader:
         self.lock = threading.Lock()
         self.background_thread = None
         # Message handlers
-        self.status_timer = self.reactor.register_timer(
-            self._status_event, self.reactor.NOW)
+        self.status_timer = self.reactor.register_timer(self._status_event)
         self.status_cmd = None
         handlers = {
             '#unknown': self.handle_unknown,
@@ -60,10 +62,10 @@ class SerialReader:
         # Initial connection
         logging.info("Starting serial connect")
         while 1:
-            starttime = time.time()
+            starttime = self.reactor.monotonic()
             try:
                 self.ser = serial.Serial(self.serialport, self.baud, timeout=0)
-            except OSError, e:
+            except (OSError, serial.SerialException), e:
                 logging.warn("Unable to open port: %s" % (e,))
                 self.reactor.pause(starttime + 5.)
                 continue
@@ -78,8 +80,6 @@ class SerialReader:
             if identify_data is None:
                 logging.warn("Timeout on serial connect")
                 self.disconnect()
-                self.ser.close()
-                self.ser = None
                 continue
             break
         msgparser = msgproto.MessageParser()
@@ -88,14 +88,29 @@ class SerialReader:
         self.register_callback(self.handle_unknown, '#unknown')
         logging.info("Loaded %d commands (%s)" % (
             len(msgparser.messages_by_id), msgparser.version))
-        # Setup for runtime
+        logging.info("MCU config: %s" % (" ".join(
+            ["%s=%s" % (k, v) for k, v in msgparser.config.items()])))
+        # Setup baud adjust
         mcu_baud = float(msgparser.config.get('SERIAL_BAUD', 0.))
         if mcu_baud:
             baud_adjust = self.BITS_PER_BYTE / mcu_baud
             self.ffi_lib.serialqueue_set_baud_adjust(
                 self.serialqueue, baud_adjust)
+        # Enable periodic get_status timer
         get_status = msgparser.lookup_command('get_status')
         self.status_cmd = get_status.encode()
+        self.reactor.update_timer(self.status_timer, self.reactor.NOW)
+        # Load initial last_ack_clock/last_ack_time
+        uptime_msg = msgparser.create_command('get_uptime')
+        params = self.send_with_response(uptime_msg, 'uptime')
+        self.last_ack_clock = (params['high'] << 32) | params['clock']
+        self.last_ack_time = params['#receive_time']
+        # Make sure est_clock is calculated
+        starttime = eventtime = self.reactor.monotonic()
+        while not self.est_clock:
+            if eventtime > starttime + 5.:
+                raise error("timeout on est_clock calculation")
+            eventtime = self.reactor.pause(eventtime + 0.010)
     def connect_file(self, debugoutput, dictionary, pace=False):
         self.ser = debugoutput
         self.msgparser.process_identify(dictionary, decompress=False)
@@ -104,19 +119,21 @@ class SerialReader:
             est_clock = float(self.msgparser.config['CLOCK_FREQ'])
         self.serialqueue = self.ffi_lib.serialqueue_alloc(self.ser.fileno(), 1)
         self.est_clock = est_clock
-        self.last_ack_time = time.time()
+        self.last_ack_time = self.reactor.monotonic()
         self.last_ack_clock = 0
         self.ffi_lib.serialqueue_set_clock_est(
             self.serialqueue, self.est_clock, self.last_ack_time
             , self.last_ack_clock)
     def disconnect(self):
-        if self.serialqueue is None:
-            return
+        if self.serialqueue is not None:
             self.ffi_lib.serialqueue_exit(self.serialqueue)
             if self.background_thread is not None:
                 self.background_thread.join()
             self.ffi_lib.serialqueue_free(self.serialqueue)
             self.background_thread = self.serialqueue = None
+        if self.ser is not None:
+            self.ser.close()
+            self.ser = None
     def stats(self, eventtime):
         if self.serialqueue is None:
             return ""
@@ -127,8 +144,6 @@ class SerialReader:
             self.est_clock, self.last_ack_time, self.last_ack_clock)
         return sqstats + tstats
     def _status_event(self, eventtime):
-        if self.status_cmd is None:
-            return eventtime + 0.1
         self.send(self.status_cmd)
         return eventtime + 1.0
     # Serial response callbacks
@@ -162,11 +177,9 @@ class SerialReader:
     def encode_and_send(self, data, minclock, reqclock, cq):
         self.ffi_lib.serialqueue_encode_and_send(
             self.serialqueue, cq, data, len(data), minclock, reqclock)
-    def send_with_response(self, cmd, name):
-        src = SerialRetryCommand(self, cmd, name)
+    def send_with_response(self, cmd, name, oid=None):
+        src = SerialRetryCommand(self, cmd, name, oid)
         return src.get_response()
-    def send_flush(self):
-        self.ffi_lib.serialqueue_flush_ready(self.serialqueue)
     def alloc_command_queue(self):
         return self.ffi_main.gc(self.ffi_lib.serialqueue_alloc_commandqueue(),
                                 self.ffi_lib.serialqueue_free_commandqueue)
@@ -226,16 +239,21 @@ class SerialReader:
 
 # Class to retry sending of a query command until a given response is received
 class SerialRetryCommand:
+    TIMEOUT_TIME = 5.0
     RETRY_TIME = 0.500
-    def __init__(self, serial, cmd, name):
+    def __init__(self, serial, cmd, name, oid=None):
         self.serial = serial
         self.cmd = cmd
         self.name = name
+        self.oid = oid
         self.response = None
-        self.min_query_time = time.time()
-        self.serial.register_callback(self.handle_callback, self.name)
+        self.min_query_time = self.serial.reactor.monotonic()
+        self.serial.register_callback(self.handle_callback, self.name, self.oid)
         self.send_timer = self.serial.reactor.register_timer(
             self.send_event, self.serial.reactor.NOW)
+    def unregister(self):
+        self.serial.unregister_callback(self.name, self.oid)
+        self.serial.reactor.unregister_timer(self.send_timer)
     def send_event(self, eventtime):
         if self.response is not None:
             return self.serial.reactor.NEVER
@@ -246,11 +264,13 @@ class SerialRetryCommand:
         if last_sent_time >= self.min_query_time:
             self.response = params
     def get_response(self):
-        eventtime = time.time()
+        eventtime = self.serial.reactor.monotonic()
         while self.response is None:
             eventtime = self.serial.reactor.pause(eventtime + 0.05)
-        self.serial.unregister_callback(self.name)
-        self.serial.reactor.unregister_timer(self.send_timer)
+            if eventtime > self.min_query_time + self.TIMEOUT_TIME:
+                self.unregister()
+                raise error("Timeout on wait for '%s' response" % (self.name,))
+        self.unregister()
         return self.response
 
 # Code to start communication and download message type dictionary
@@ -267,7 +287,7 @@ class SerialBootStrap:
         self.send_timer = self.serial.reactor.register_timer(
             self.send_event, self.serial.reactor.NOW)
     def get_identify_data(self, timeout):
-        eventtime = time.time()
+        eventtime = self.serial.reactor.monotonic()
         while not self.is_done and eventtime <= timeout:
             eventtime = self.serial.reactor.pause(eventtime + 0.05)
         self.serial.unregister_callback('identify_response')
@@ -305,10 +325,23 @@ def stk500v2_leave(ser, reactor):
     ser.read(1)
     # Send stk500v2 leave programmer sequence
     ser.baudrate = 115200
-    reactor.pause(time.time() + 0.100)
+    reactor.pause(reactor.monotonic() + 0.100)
     ser.read(4096)
     ser.write('\x1b\x01\x00\x01\x0e\x11\x04')
-    reactor.pause(time.time() + 0.050)
+    reactor.pause(reactor.monotonic() + 0.050)
     res = ser.read(4096)
     logging.debug("Got %s from stk500v2" % (repr(res),))
     ser.baudrate = origbaud
+
+# Attempt an arduino style reset on a serial port
+def arduino_reset(serialport, reactor):
+    # First try opening the port at 1200 baud
+    ser = serial.Serial(serialport, 1200, timeout=0)
+    ser.read(1)
+    reactor.pause(reactor.monotonic() + 0.100)
+    # Then try toggling DTR
+    ser.dtr = True
+    reactor.pause(reactor.monotonic() + 0.100)
+    ser.dtr = False
+    reactor.pause(reactor.monotonic() + 0.100)
+    ser.close()

klippy/serialqueue.c

@@ -23,7 +23,7 @@
 #include <termios.h> // tcflush
 #include <unistd.h> // pipe
 #include "list.h" // list_add_tail
-#include "pyhelper.h" // get_time
+#include "pyhelper.h" // get_monotonic
 #include "serialqueue.h" // struct queue_message
 
 
@@ -149,11 +149,11 @@ static void
 pollreactor_run(struct pollreactor *pr)
 {
     pr->must_exit = 0;
-    double eventtime = get_time();
+    double eventtime = get_monotonic();
     while (! pr->must_exit) {
         int timeout = pollreactor_check_timers(pr, eventtime);
         int ret = poll(pr->fds, pr->num_fds, timeout);
-        eventtime = get_time();
+        eventtime = get_monotonic();
         if (ret > 0) {
             int i;
             for (i=0; i<pr->num_fds; i++)
@@ -356,7 +356,6 @@ struct serialqueue {
     struct list_head pending_queues;
     int ready_bytes, stalled_bytes;
     uint64_t need_kick_clock;
-    int can_delay_writes;
     // Received messages
     struct list_head receive_queue;
     // Debugging
@@ -488,7 +487,8 @@ handle_message(struct serialqueue *sq, double eventtime, int len)
     if (rseq != sq->receive_seq)
         // New sequence number
         update_receive_seq(sq, eventtime, rseq);
-    else if (len == MESSAGE_MIN && rseq > sq->retransmit_seq)
+    else if (len == MESSAGE_MIN && rseq > sq->retransmit_seq
+             && !list_empty(&sq->sent_queue))
         // Duplicate sequence number in an empty message is a nak
         pollreactor_update_timer(&sq->pr, SQPT_RETRANSMIT, PR_NOW);
 
@@ -496,7 +496,7 @@ handle_message(struct serialqueue *sq, double eventtime, int len)
         // Add message to receive queue
         struct queue_message *qm = message_fill(sq->input_buf, len);
         qm->sent_time = sq->last_receive_sent_time;
-        qm->receive_time = eventtime;
+        qm->receive_time = get_monotonic(); // must be time post read()
         list_add_tail(&qm->node, &sq->receive_queue);
         check_wake_receive(sq);
     }
@@ -695,11 +695,9 @@ check_send_command(struct serialqueue *sq, double eventtime)
     // Check for messages to send
     if (sq->ready_bytes >= MESSAGE_PAYLOAD_MAX)
         return PR_NOW;
-    if (! sq->can_delay_writes) {
+    if (! sq->est_clock) {
         if (sq->ready_bytes)
             return PR_NOW;
-        if (sq->est_clock)
-            sq->can_delay_writes = 1;
         sq->need_kick_clock = MAX_CLOCK;
         return PR_NEVER;
     }
@@ -986,16 +984,6 @@ serialqueue_set_clock_est(struct serialqueue *sq, double est_clock
     pthread_mutex_unlock(&sq->lock);
 }
 
-// Flush all messages in a "ready" state
-void
-serialqueue_flush_ready(struct serialqueue *sq)
-{
-    pthread_mutex_lock(&sq->lock);
-    sq->can_delay_writes = 0;
-    pthread_mutex_unlock(&sq->lock);
-    kick_bg_thread(sq);
-}
-
 // Return a string buffer containing statistics for the serial port
 void
 serialqueue_get_stats(struct serialqueue *sq, char *buf, int len)

klippy/serialqueue.h

@@ -61,7 +61,6 @@ void serialqueue_pull(struct serialqueue *sq, struct pull_queue_message *pqm);
 void serialqueue_set_baud_adjust(struct serialqueue *sq, double baud_adjust);
 void serialqueue_set_clock_est(struct serialqueue *sq, double est_clock
                                , double last_ack_time, uint64_t last_ack_clock);
-void serialqueue_flush_ready(struct serialqueue *sq);
 void serialqueue_get_stats(struct serialqueue *sq, char *buf, int len);
 int serialqueue_extract_old(struct serialqueue *sq, int sentq
                             , struct pull_queue_message *q, int max);

klippy/stepcompress.c

@@ -1,6 +1,6 @@
 // Stepper pulse schedule compression
 //
-// Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 //
@@ -31,10 +31,8 @@ struct stepcompress {
     uint64_t *queue, *queue_end, *queue_pos, *queue_next;
     // Internal tracking
     uint32_t max_error;
-    // Error checking
-    uint32_t errors;
     // Message generation
-    uint64_t last_step_clock;
+    uint64_t last_step_clock, homing_clock;
     struct list_head msg_queue;
     uint32_t queue_step_msgid, set_next_step_dir_msgid, oid;
     int sdir, invert_sdir;
@@ -174,6 +172,9 @@ compress_bisect_add(struct stepcompress *sc)
                 zerointerval = interval;
                 zerocount = count;
             }
+            if (count > 0x200)
+                // No 'add' will improve sequence; avoid integer overflow
+                break;
         }
 
         // Check if a greater or lesser add could extend the sequence
@@ -221,27 +222,30 @@ compress_bisect_add(struct stepcompress *sc)
  * Step compress checking
  ****************************************************************/
 
+#define ERROR_RET -989898989
+
 // Verify that a given 'step_move' matches the actual step times
-static void
+static int
 check_line(struct stepcompress *sc, struct step_move move)
 {
     if (!CHECK_LINES)
-        return;
+        return 0;
     if (move.count == 1) {
         if (move.interval != (uint32_t)(*sc->queue_pos - sc->last_step_clock)
             || *sc->queue_pos < sc->last_step_clock) {
-            errorf("Count 1 point out of range: %d %d %d"
-                   , move.interval, move.count, move.add);
-            sc->errors++;
+            errorf("stepcompress o=%d i=%d c=%d a=%d:"
+                   " Count 1 point out of range (%lld)"
+                   , sc->oid, move.interval, move.count, move.add
+                   , (long long)(*sc->queue_pos - sc->last_step_clock));
+            return ERROR_RET;
         }
-        return;
+        return 0;
     }
-    int err = 0;
     if (!move.count || (!move.interval && !move.add)
         || move.interval >= 0x80000000) {
-        errorf("Point out of range: %d %d %d"
-               , move.interval, move.count, move.add);
-        err++;
+        errorf("stepcompress o=%d i=%d c=%d a=%d: Invalid sequence"
+               , sc->oid, move.interval, move.count, move.add);
+        return ERROR_RET;
     }
     uint32_t interval = move.interval, p = 0;
     uint16_t i;
@@ -249,18 +253,21 @@ check_line(struct stepcompress *sc, struct step_move move)
         struct points point = minmax_point(sc, sc->queue_pos + i);
         p += interval;
         if (p < point.minp || p > point.maxp) {
-            errorf("Point %d of %d: %d not in %d:%d"
-                   , i+1, move.count, p, point.minp, point.maxp);
-            err++;
+            errorf("stepcompress o=%d i=%d c=%d a=%d: Point %d: %d not in %d:%d"
+                   , sc->oid, move.interval, move.count, move.add
+                   , i+1, p, point.minp, point.maxp);
+            return ERROR_RET;
         }
         if (interval >= 0x80000000) {
-            errorf("Point %d of %d: interval overflow %d"
-                   , i+1, move.count, interval);
-            err++;
+            errorf("stepcompress o=%d i=%d c=%d a=%d:"
+                   " Point %d: interval overflow %d"
+                   , sc->oid, move.interval, move.count, move.add
+                   , i+1, interval);
+            return ERROR_RET;
         }
         interval += move.add;
     }
-    sc->errors += err;
+    return 0;
 }
 
 
@@ -268,22 +275,6 @@ check_line(struct stepcompress *sc, struct step_move move)
  * Step compress interface
  ****************************************************************/
 
-#define likely(x)       __builtin_expect(!!(x), 1)
-
-// Wrapper around sqrt() to handle small negative numbers
-static double
-_safe_sqrt(double v)
-{
-    if (v > -0.001)
-        // Due to floating point truncation, it's possible to get a
-        // small negative number - treat it as zero.
-        return 0.;
-    return sqrt(v);
-}
-static inline double safe_sqrt(double v) {
-    return likely(v >= 0.) ? sqrt(v) : _safe_sqrt(v);
-}
-
 // Allocate a new 'stepcompress' object
 struct stepcompress *
 stepcompress_alloc(uint32_t max_error, uint32_t queue_step_msgid
@@ -314,14 +305,16 @@ stepcompress_free(struct stepcompress *sc)
 }
 
 // Convert previously scheduled steps into commands for the mcu
-static void
+static int
 stepcompress_flush(struct stepcompress *sc, uint64_t move_clock)
 {
     if (sc->queue_pos >= sc->queue_next)
-        return;
+        return 0;
     while (move_clock > sc->last_step_clock) {
         struct step_move move = compress_bisect_add(sc);
-        check_line(sc, move);
+        int ret = check_line(sc, move);
+        if (ret)
+            return ret;
 
         uint32_t msg[5] = {
             sc->queue_step_msgid, sc->oid, move.interval, move.count, move.add
@@ -332,10 +325,13 @@ stepcompress_flush(struct stepcompress *sc, uint64_t move_clock)
             // Be careful with 32bit overflow
             sc->last_step_clock = qm->req_clock = *sc->queue_pos;
         } else {
-            uint32_t addfactor = move.count*(move.count-1)/2;
+            int32_t addfactor = move.count*(move.count-1)/2;
             uint32_t ticks = move.add*addfactor + move.interval*move.count;
             sc->last_step_clock += ticks;
         }
+        if (sc->homing_clock)
+            // When homing, all steps should be sent prior to homing_clock
+            qm->min_clock = qm->req_clock = sc->homing_clock;
         list_add_tail(&qm->node, &sc->msg_queue);
 
         if (sc->queue_pos + move.count >= sc->queue_next) {
@@ -344,232 +340,325 @@ stepcompress_flush(struct stepcompress *sc, uint64_t move_clock)
         }
         sc->queue_pos += move.count;
     }
+    return 0;
 }
 
 // Send the set_next_step_dir command
-static void
+static int
 set_next_step_dir(struct stepcompress *sc, int sdir)
 {
+    if (sc->sdir == sdir)
+        return 0;
     sc->sdir = sdir;
-    stepcompress_flush(sc, UINT64_MAX);
+    int ret = stepcompress_flush(sc, UINT64_MAX);
+    if (ret)
+        return ret;
     uint32_t msg[3] = {
         sc->set_next_step_dir_msgid, sc->oid, sdir ^ sc->invert_sdir
     };
     struct queue_message *qm = message_alloc_and_encode(msg, 3);
-    qm->req_clock = sc->last_step_clock;
+    qm->req_clock = sc->homing_clock ?: sc->last_step_clock;
     list_add_tail(&qm->node, &sc->msg_queue);
+    return 0;
 }
 
 // Check if the internal queue needs to be expanded, and expand if so
-static inline void
-check_expand(struct stepcompress *sc, int sdir, int count)
+static int
+_check_push(struct stepcompress *sc)
 {
-    if (sdir != sc->sdir)
-        set_next_step_dir(sc, sdir);
-    if (sc->queue_next + count > sc->queue_end)
-        expand_queue(sc, count);
+    if (sc->queue_next - sc->queue_pos > 65535 + 2000) {
+        // No point in keeping more than 64K steps in memory
+        int ret = stepcompress_flush(sc, *(sc->queue_next - 65535));
+        if (ret)
+            return ret;
     }
-
-// Schedule a step event at the specified step_clock time
-void
-stepcompress_push(struct stepcompress *sc, double step_clock, int32_t sdir)
-{
-    sdir = !!sdir;
-    check_expand(sc, sdir, 1);
-    step_clock += 0.5;
-    *sc->queue_next++ = step_clock;
-}
-
-// Schedule 'steps' number of steps with a constant time between steps
-// using the formula: step_clock = clock_offset + step_num*factor
-int32_t
-stepcompress_push_factor(struct stepcompress *sc
-                         , double steps, double step_offset
-                         , double clock_offset, double factor)
-{
-    // Calculate number of steps to take
-    int sdir = 1;
-    if (steps < 0) {
-        sdir = 0;
-        steps = -steps;
-        step_offset = -step_offset;
-    }
-    int count = steps + .5 - step_offset;
-    if (count <= 0 || count > 1000000) {
-        if (count && steps)
-            errorf("push_factor invalid count %d %f %f %f %f"
-                   , sc->oid, steps, step_offset, clock_offset, factor);
+    expand_queue(sc, 1);
     return 0;
 }
-    check_expand(sc, sdir, count);
-
-    // Calculate each step time
-    uint64_t *qn = sc->queue_next, *end = &qn[count];
-    clock_offset += 0.5;
-    double pos = step_offset + .5;
-    while (qn < end) {
-        *qn++ = clock_offset + pos*factor;
-        pos += 1.0;
-    }
-    sc->queue_next = qn;
-    return sdir ? count : -count;
-}
-
-// Schedule 'steps' number of steps using the formula:
-//  step_clock = clock_offset + sqrt(step_num*factor + sqrt_offset)
-int32_t
-stepcompress_push_sqrt(struct stepcompress *sc, double steps, double step_offset
-                       , double clock_offset, double sqrt_offset, double factor)
+static inline int
+check_push(struct stepcompress *sc, uint64_t **pqnext, uint64_t **pqend
+           , uint64_t c)
 {
-    // Calculate number of steps to take
-    int sdir = 1;
-    if (steps < 0) {
-        sdir = 0;
-        steps = -steps;
-        step_offset = -step_offset;
+    if (unlikely(*pqnext >= *pqend)) {
+        sc->queue_next = *pqnext;
+        int ret = _check_push(sc);
+        if (ret)
+            return ret;
+        *pqnext = sc->queue_next;
+        *pqend = sc->queue_end;
     }
-    int count = steps + .5 - step_offset;
-    if (count <= 0 || count > 1000000) {
-        if (count && steps)
-            errorf("push_sqrt invalid count %d %f %f %f %f %f"
-                   , sc->oid, steps, step_offset, clock_offset, sqrt_offset
-                   , factor);
+    *(*pqnext)++ = c;
     return 0;
 }
-    check_expand(sc, sdir, count);
-
-    // Calculate each step time
-    uint64_t *qn = sc->queue_next, *end = &qn[count];
-    clock_offset += 0.5;
-    double pos = step_offset + .5 + sqrt_offset/factor;
-    while (qn < end) {
-        double v = safe_sqrt(pos*factor);
-        *qn++ = clock_offset + (factor >= 0. ? v : -v);
-        pos += 1.0;
-    }
-    sc->queue_next = qn;
-    return sdir ? count : -count;
-}
-
-// Schedule 'count' number of steps using the delta kinematic const speed
-int32_t
-stepcompress_push_delta_const(
-    struct stepcompress *sc, double clock_offset, double dist, double start_pos
-    , double inv_velocity, double step_dist
-    , double height, double closestxy_d, double closest_height2, double movez_r)
-{
-    // Calculate number of steps to take
-    double movexy_r = movez_r ? sqrt(1. - movez_r*movez_r) : 1.;
-    double reldist = closestxy_d - movexy_r*dist;
-    double end_height = safe_sqrt(closest_height2 - reldist*reldist);
-    int count = (end_height - height + movez_r*dist) / step_dist + .5;
-    if (count <= 0 || count > 1000000) {
-        if (count)
-            errorf("push_delta_const invalid count %d %d %f %f %f %f %f %f %f %f"
-                   , sc->oid, count, clock_offset, dist, step_dist, start_pos
-                   , closest_height2, height, movez_r, inv_velocity);
-        return 0;
-    }
-    check_expand(sc, step_dist > 0., count);
-
-    // Calculate each step time
-    uint64_t *qn = sc->queue_next, *end = &qn[count];
-    clock_offset += 0.5;
-    start_pos += movexy_r*closestxy_d;
-    height += .5 * step_dist;
-    if (!movez_r) {
-        // Optmized case for common XY only moves (no Z movement)
-        while (qn < end) {
-            double v = safe_sqrt(closest_height2 - height*height);
-            double pos = start_pos + (step_dist > 0. ? -v : v);
-            *qn++ = clock_offset + pos * inv_velocity;
-            height += step_dist;
-        }
-    } else if (!movexy_r) {
-        // Optmized case for Z only moves
-        double v = (step_dist > 0. ? -end_height : end_height);
-        while (qn < end) {
-            double pos = start_pos + movez_r*height + v;
-            *qn++ = clock_offset + pos * inv_velocity;
-            height += step_dist;
-        }
-    } else {
-        // General case (handles XY+Z moves)
-        while (qn < end) {
-            double relheight = movexy_r*height - movez_r*closestxy_d;
-            double v = safe_sqrt(closest_height2 - relheight*relheight);
-            double pos = start_pos + movez_r*height + (step_dist > 0. ? -v : v);
-            *qn++ = clock_offset + pos * inv_velocity;
-            height += step_dist;
-        }
-    }
-    sc->queue_next = qn;
-    return step_dist > 0. ? count : -count;
-}
-
-// Schedule 'count' number of steps using delta kinematic acceleration
-int32_t
-stepcompress_push_delta_accel(
-    struct stepcompress *sc, double clock_offset, double dist, double start_pos
-    , double accel_multiplier, double step_dist
-    , double height, double closestxy_d, double closest_height2, double movez_r)
-{
-    // Calculate number of steps to take
-    double movexy_r = movez_r ? sqrt(1. - movez_r*movez_r) : 1.;
-    double reldist = closestxy_d - movexy_r*dist;
-    double end_height = safe_sqrt(closest_height2 - reldist*reldist);
-    int count = (end_height - height + movez_r*dist) / step_dist + .5;
-    if (count <= 0 || count > 1000000) {
-        if (count)
-            errorf("push_delta_accel invalid count %d %d %f %f %f %f %f %f %f %f"
-                   , sc->oid, count, clock_offset, dist, step_dist, start_pos
-                   , closest_height2, height, movez_r, accel_multiplier);
-        return 0;
-    }
-    check_expand(sc, step_dist > 0., count);
-
-    // Calculate each step time
-    uint64_t *qn = sc->queue_next, *end = &qn[count];
-    clock_offset += 0.5;
-    start_pos += movexy_r*closestxy_d;
-    height += .5 * step_dist;
-    while (qn < end) {
-        double relheight = movexy_r*height - movez_r*closestxy_d;
-        double v = safe_sqrt(closest_height2 - relheight*relheight);
-        double pos = start_pos + movez_r*height + (step_dist > 0. ? -v : v);
-        v = safe_sqrt(pos * accel_multiplier);
-        *qn++ = clock_offset + (accel_multiplier >= 0. ? v : -v);
-        height += step_dist;
-    }
-    sc->queue_next = qn;
-    return step_dist > 0. ? count : -count;
-}
 
 // Reset the internal state of the stepcompress object
-void
+int
 stepcompress_reset(struct stepcompress *sc, uint64_t last_step_clock)
 {
-    stepcompress_flush(sc, UINT64_MAX);
+    int ret = stepcompress_flush(sc, UINT64_MAX);
+    if (ret)
+        return ret;
     sc->last_step_clock = last_step_clock;
     sc->sdir = -1;
+    return 0;
+}
+
+// Indicate the stepper is in homing mode (or done homing if zero)
+int
+stepcompress_set_homing(struct stepcompress *sc, uint64_t homing_clock)
+{
+    int ret = stepcompress_flush(sc, UINT64_MAX);
+    if (ret)
+        return ret;
+    sc->homing_clock = homing_clock;
+    return 0;
 }
 
 // Queue an mcu command to go out in order with stepper commands
-void
+int
 stepcompress_queue_msg(struct stepcompress *sc, uint32_t *data, int len)
 {
-    stepcompress_flush(sc, UINT64_MAX);
+    int ret = stepcompress_flush(sc, UINT64_MAX);
+    if (ret)
+        return ret;
 
     struct queue_message *qm = message_alloc_and_encode(data, len);
-    qm->req_clock = sc->last_step_clock;
+    qm->req_clock = sc->homing_clock ?: sc->last_step_clock;
     list_add_tail(&qm->node, &sc->msg_queue);
+    return 0;
 }
 
-// Return the count of internal errors found
-uint32_t
-stepcompress_get_errors(struct stepcompress *sc)
+
+/****************************************************************
+ * Motion to step conversions
+ ****************************************************************/
+
+// Wrapper around sqrt() to handle small negative numbers
+static double
+_safe_sqrt(double v)
 {
-    return sc->errors;
+    // Due to floating point truncation, it's possible to get a small
+    // negative number - treat it as zero.
+    if (v < -0.001)
+        errorf("safe_sqrt of %.9f", v);
+    return 0.;
+}
+static inline double safe_sqrt(double v) {
+    return likely(v >= 0.) ? sqrt(v) : _safe_sqrt(v);
+}
+
+// Schedule a step event at the specified step_clock time
+int
+stepcompress_push(struct stepcompress *sc, double step_clock, int32_t sdir)
+{
+    int ret = set_next_step_dir(sc, !!sdir);
+    if (ret)
+        return ret;
+    step_clock += 0.5;
+    uint64_t *qnext = sc->queue_next, *qend = sc->queue_end;
+    ret = check_push(sc, &qnext, &qend, step_clock);
+    if (ret)
+        return ret;
+    sc->queue_next = qnext;
+    return 0;
+}
+
+// Common suffixes: _sd is step distance (a unit length the same
+// distance the stepper moves on each step), _sv is step velocity (in
+// units of step distance per clock tick), _sd2 is step distance
+// squared, _r is ratio (scalar usually between 0.0 and 1.0).  Times
+// are represented as clock ticks (a unit of time determined by a
+// micro-controller tick) and acceleration is in units of step
+// distance per clock ticks squared.
+
+// Schedule 'steps' number of steps at constant acceleration. If
+// acceleration is zero (ie, constant velocity) it uses the formula:
+//  step_clock = clock_offset + step_num/start_sv
+// Otherwise it uses the formula:
+//  step_clock = (clock_offset + sqrt(2*step_num/accel + (start_sv/accel)**2)
+//                - start_sv/accel)
+int32_t
+stepcompress_push_const(
+    struct stepcompress *sc, double clock_offset
+    , double step_offset, double steps, double start_sv, double accel)
+{
+    // Calculate number of steps to take
+    int sdir = 1;
+    if (steps < 0) {
+        sdir = 0;
+        steps = -steps;
+        step_offset = -step_offset;
+    }
+    int count = steps + .5 - step_offset;
+    if (count <= 0 || count > 10000000) {
+        if (count && steps) {
+            errorf("push_const invalid count %d %f %f %f %f %f"
+                   , sc->oid, clock_offset, step_offset, steps
+                   , start_sv, accel);
+            return ERROR_RET;
+        }
+        return 0;
+    }
+    int ret = set_next_step_dir(sc, sdir);
+    if (ret)
+        return ret;
+    int res = sdir ? count : -count;
+
+    // Calculate each step time
+    clock_offset += 0.5;
+    double pos = step_offset + .5;
+    uint64_t *qnext = sc->queue_next, *qend = sc->queue_end;
+    if (!accel) {
+        // Move at constant velocity (zero acceleration)
+        double inv_cruise_sv = 1. / start_sv;
+        while (count--) {
+            uint64_t c = clock_offset + pos*inv_cruise_sv;
+            int ret = check_push(sc, &qnext, &qend, c);
+            if (ret)
+                return ret;
+            pos += 1.0;
+        }
+    } else {
+        // Move with constant acceleration
+        double inv_accel = 1. / accel;
+        clock_offset -= start_sv * inv_accel;
+        pos += .5 * start_sv*start_sv * inv_accel;
+        double accel_multiplier = 2. * inv_accel;
+        while (count--) {
+            double v = safe_sqrt(pos * accel_multiplier);
+            uint64_t c = clock_offset + (accel_multiplier >= 0. ? v : -v);
+            int ret = check_push(sc, &qnext, &qend, c);
+            if (ret)
+                return ret;
+            pos += 1.0;
+        }
+    }
+    sc->queue_next = qnext;
+    return res;
+}
+
+// Schedule steps using delta kinematics
+static int32_t
+_stepcompress_push_delta(
+    struct stepcompress *sc, int sdir
+    , double clock_offset, double move_sd, double start_sv, double accel
+    , double height, double startxy_sd, double arm_sd, double movez_r)
+{
+    // Calculate number of steps to take
+    double movexy_r = movez_r ? sqrt(1. - movez_r*movez_r) : 1.;
+    double arm_sd2 = arm_sd * arm_sd;
+    double endxy_sd = startxy_sd - movexy_r*move_sd;
+    double end_height = safe_sqrt(arm_sd2 - endxy_sd*endxy_sd);
+    int count = (end_height + movez_r*move_sd - height) * (sdir ? 1. : -1.) + .5;
+    if (count <= 0 || count > 10000000) {
+        if (count) {
+            errorf("push_delta invalid count %d %d %f %f %f %f %f %f %f %f"
+                   , sc->oid, count, clock_offset, move_sd, start_sv, accel
+                   , height, startxy_sd, arm_sd, movez_r);
+            return ERROR_RET;
+        }
+        return 0;
+    }
+    int ret = set_next_step_dir(sc, sdir);
+    if (ret)
+        return ret;
+    int res = sdir ? count : -count;
+
+    // Calculate each step time
+    clock_offset += 0.5;
+    height += (sdir ? .5 : -.5);
+    uint64_t *qnext = sc->queue_next, *qend = sc->queue_end;
+    if (!accel) {
+        // Move at constant velocity (zero acceleration)
+        double inv_cruise_sv = 1. / start_sv;
+        if (!movez_r) {
+            // Optimized case for common XY only moves (no Z movement)
+            while (count--) {
+                double v = safe_sqrt(arm_sd2 - height*height);
+                double pos = startxy_sd + (sdir ? -v : v);
+                uint64_t c = clock_offset + pos * inv_cruise_sv;
+                int ret = check_push(sc, &qnext, &qend, c);
+                if (ret)
+                    return ret;
+                height += (sdir ? 1. : -1.);
+            }
+        } else if (!movexy_r) {
+            // Optimized case for Z only moves
+            double pos = (sdir ? height-end_height : end_height-height);
+            while (count--) {
+                uint64_t c = clock_offset + pos * inv_cruise_sv;
+                int ret = check_push(sc, &qnext, &qend, c);
+                if (ret)
+                    return ret;
+                pos += 1.;
+            }
+        } else {
+            // General case (handles XY+Z moves)
+            double start_pos = movexy_r*startxy_sd, zoffset = movez_r*startxy_sd;
+            while (count--) {
+                double relheight = movexy_r*height - zoffset;
+                double v = safe_sqrt(arm_sd2 - relheight*relheight);
+                double pos = start_pos + movez_r*height + (sdir ? -v : v);
+                uint64_t c = clock_offset + pos * inv_cruise_sv;
+                int ret = check_push(sc, &qnext, &qend, c);
+                if (ret)
+                    return ret;
+                height += (sdir ? 1. : -1.);
+            }
+        }
+    } else {
+        // Move with constant acceleration
+        double start_pos = movexy_r*startxy_sd, zoffset = movez_r*startxy_sd;
+        double inv_accel = 1. / accel;
+        clock_offset -= start_sv * inv_accel;
+        start_pos += 0.5 * start_sv*start_sv * inv_accel;
+        double accel_multiplier = 2. * inv_accel;
+        while (count--) {
+            double relheight = movexy_r*height - zoffset;
+            double v = safe_sqrt(arm_sd2 - relheight*relheight);
+            double pos = start_pos + movez_r*height + (sdir ? -v : v);
+            v = safe_sqrt(pos * accel_multiplier);
+            uint64_t c = clock_offset + (accel_multiplier >= 0. ? v : -v);
+            int ret = check_push(sc, &qnext, &qend, c);
+            if (ret)
+                return ret;
+            height += (sdir ? 1. : -1.);
+        }
+    }
+    sc->queue_next = qnext;
+    return res;
+}
+
+int32_t
+stepcompress_push_delta(
+    struct stepcompress *sc, double clock_offset, double move_sd
+    , double start_sv, double accel
+    , double height, double startxy_sd, double arm_sd, double movez_r)
+{
+    double reversexy_sd = startxy_sd + arm_sd*movez_r;
+    if (reversexy_sd <= 0.)
+        // All steps are in down direction
+        return _stepcompress_push_delta(
+            sc, 0, clock_offset, move_sd, start_sv, accel
+            , height, startxy_sd, arm_sd, movez_r);
+    double movexy_r = movez_r ? sqrt(1. - movez_r*movez_r) : 1.;
+    if (reversexy_sd >= move_sd * movexy_r)
+        // All steps are in up direction
+        return _stepcompress_push_delta(
+            sc, 1, clock_offset, move_sd, start_sv, accel
+            , height, startxy_sd, arm_sd, movez_r);
+    // Steps in both up and down direction
+    int res1 = _stepcompress_push_delta(
+        sc, 1, clock_offset, reversexy_sd / movexy_r, start_sv, accel
+        , height, startxy_sd, arm_sd, movez_r);
+    if (res1 == ERROR_RET)
+        return res1;
+    int res2 = _stepcompress_push_delta(
+        sc, 0, clock_offset, move_sd, start_sv, accel
+        , height + res1, startxy_sd, arm_sd, movez_r);
+    if (res2 == ERROR_RET)
+        return res2;
+    return res1 + res2;
 }
 
 
@@ -655,13 +744,16 @@ heap_replace(struct steppersync *ss, uint64_t req_clock)
 }
 
 // Find and transmit any scheduled steps prior to the given 'move_clock'
-void
+int
 steppersync_flush(struct steppersync *ss, uint64_t move_clock)
 {
     // Flush each stepcompress to the specified move_clock
     int i;
-    for (i=0; i<ss->sc_num; i++)
-        stepcompress_flush(ss->sc_list[i], move_clock);
+    for (i=0; i<ss->sc_num; i++) {
+        int ret = stepcompress_flush(ss->sc_list[i], move_clock);
+        if (ret)
+            return ret;
+    }
 
     // Order commands by the reqclock of each pending command
     struct list_head msgs;
@@ -701,4 +793,5 @@ steppersync_flush(struct steppersync *ss, uint64_t move_clock)
     // Transmit commands
     if (!list_empty(&msgs))
         serialqueue_send_batch(ss->sq, ss->cq, &msgs);
+    return 0;
 }

klippy/stepper.py

@@ -8,24 +8,26 @@ import homing
 
 class PrinterStepper:
     def __init__(self, printer, config, name):
-        self.printer = printer
-        self.config = config
         self.name = name
-        self.mcu_stepper = self.mcu_enable = self.mcu_endstop = None
 
-        self.step_dist = config.getfloat('step_distance')
+        self.step_dist = config.getfloat('step_distance', above=0.)
         self.inv_step_dist = 1. / self.step_dist
         self.min_stop_interval = 0.
 
-        self.homing_speed = config.getfloat('homing_speed', 5.0)
+        self.homing_speed = config.getfloat('homing_speed', 5.0, above=0.)
         self.homing_positive_dir = config.getboolean(
             'homing_positive_dir', False)
-        self.homing_retract_dist = config.getfloat('homing_retract_dist', 5.)
-        self.homing_stepper_phases = config.getint('homing_stepper_phases', None)
-        self.homing_endstop_phase = config.getint('homing_endstop_phase', None)
-        endstop_accuracy = config.getfloat('homing_endstop_accuracy', None)
-        self.homing_endstop_accuracy = None
+        self.homing_retract_dist = config.getfloat(
+            'homing_retract_dist', 5., above=0.)
+        self.homing_stepper_phases = config.getint(
+            'homing_stepper_phases', None, minval=0)
+        endstop_accuracy = config.getfloat(
+            'homing_endstop_accuracy', None, above=0.)
+        self.homing_endstop_accuracy = self.homing_endstop_phase = None
         if self.homing_stepper_phases:
+            self.homing_endstop_phase = config.getint(
+                'homing_endstop_phase', None, minval=0
+                , maxval=self.homing_stepper_phases-1)
             if endstop_accuracy is None:
                 self.homing_endstop_accuracy = self.homing_stepper_phases//2 - 1
             elif self.homing_endstop_phase is not None:
@@ -36,34 +38,40 @@ class PrinterStepper:
                     endstop_accuracy * self.inv_step_dist))
             if self.homing_endstop_accuracy >= self.homing_stepper_phases/2:
                 logging.info("Endstop for %s is not accurate enough for stepper"
-                             " phase adjustment" % (self.config.section,))
+                             " phase adjustment" % (name,))
                 self.homing_stepper_phases = None
+            if printer.mcu.is_fileoutput():
+                self.homing_endstop_accuracy = self.homing_stepper_phases
         self.position_min = self.position_endstop = self.position_max = None
-        if config.get('endstop_pin', None) is not None:
-            self.position_min = config.getfloat('position_min', 0.)
-            self.position_endstop = config.getfloat('position_endstop')
-            self.position_max = config.getfloat('position_max', 0.)
-
-        self.need_motor_enable = True
-    def set_max_jerk(self, max_halt_velocity, max_accel):
-        jc = max_halt_velocity / max_accel
-        inv_max_step_accel = self.step_dist / max_accel
-        self.min_stop_interval = (math.sqrt(3.*inv_max_step_accel + jc**2)
-                                  - math.sqrt(inv_max_step_accel + jc**2))
-    def build_config(self):
-        max_error = self.config.getfloat('max_error', 0.000050)
-        step_pin = self.config.get('step_pin')
-        dir_pin = self.config.get('dir_pin')
-        min_stop_interval = max(0., self.min_stop_interval - max_error)
-        mcu = self.printer.mcu
-        self.mcu_stepper = mcu.create_stepper(
-            step_pin, dir_pin, min_stop_interval, max_error)
-        enable_pin = self.config.get('enable_pin', None)
+        endstop_pin = config.get('endstop_pin', None)
+        step_pin = config.get('step_pin')
+        dir_pin = config.get('dir_pin')
+        mcu = printer.mcu
+        self.mcu_stepper = mcu.create_stepper(step_pin, dir_pin)
+        self.mcu_stepper.set_step_distance(self.step_dist)
+        enable_pin = config.get('enable_pin', None)
         if enable_pin is not None:
             self.mcu_enable = mcu.create_digital_out(enable_pin, 0)
-        endstop_pin = self.config.get('endstop_pin', None)
         if endstop_pin is not None:
-            self.mcu_endstop = mcu.create_endstop(endstop_pin, self.mcu_stepper)
+            self.mcu_endstop = mcu.create_endstop(endstop_pin)
+            self.mcu_endstop.add_stepper(self.mcu_stepper)
+            self.position_min = config.getfloat('position_min', 0.)
+            self.position_max = config.getfloat(
+                'position_max', 0., above=self.position_min)
+            self.position_endstop = config.getfloat('position_endstop')
+        self.need_motor_enable = True
+    def _dist_to_time(self, dist, start_velocity, accel):
+        # Calculate the time it takes to travel a distance with constant accel
+        time_offset = start_velocity / accel
+        return math.sqrt(2. * dist / accel + time_offset**2) - time_offset
+    def set_max_jerk(self, max_halt_velocity, max_accel):
+        # Calculate the firmware's maximum halt interval time
+        last_step_time = self._dist_to_time(
+            self.step_dist, max_halt_velocity, max_accel)
+        second_last_step_time = self._dist_to_time(
+            2. * self.step_dist, max_halt_velocity, max_accel)
+        min_stop_interval = second_last_step_time - last_step_time
+        self.mcu_stepper.set_min_stop_interval(min_stop_interval)
     def motor_enable(self, move_time, enable=0):
         if enable and self.need_motor_enable:
             mcu_time = self.mcu_stepper.print_to_mcu_time(move_time)
@@ -87,8 +95,7 @@ class PrinterStepper:
         pos = self.mcu_stepper.get_mcu_position()
         pos %= self.homing_stepper_phases
         if self.homing_endstop_phase is None:
-            logging.info("Setting %s endstop phase to %d" % (
-                self.config.section, pos))
+            logging.info("Setting %s endstop phase to %d" % (self.name, pos))
             self.homing_endstop_phase = pos
             return 0
         delta = (pos - self.homing_endstop_phase) % self.homing_stepper_phases
@@ -98,4 +105,4 @@ class PrinterStepper:
             raise homing.EndstopError(
                 "Endstop %s incorrect phase (got %d vs %d)" % (
                     self.name, pos, self.homing_endstop_phase))
-        return delta
+        return delta * self.step_dist

klippy/toolhead.py

@@ -3,148 +3,171 @@
 # Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import math, logging, time
-import cartesian, delta
-
-EXTRUDE_DIFF_IGNORE = 1.02
+import math, logging
+import cartesian, corexy, delta, extruder
 
 # Common suffixes: _d is distance (in mm), _v is velocity (in
-#   mm/second), _t is time (in seconds), _r is ratio (scalar between
-#   0.0 and 1.0)
+#   mm/second), _v2 is velocity squared (mm^2/s^2), _t is time (in
+#   seconds), _r is ratio (scalar between 0.0 and 1.0)
 
 # Class to track each move request
 class Move:
-    def __init__(self, toolhead, start_pos, end_pos, speed, accel):
+    def __init__(self, toolhead, start_pos, end_pos, speed):
         self.toolhead = toolhead
         self.start_pos = tuple(start_pos)
         self.end_pos = tuple(end_pos)
-        self.accel = accel
-        self.do_calc_junction = True
+        self.accel = toolhead.max_accel
+        self.is_kinematic_move = True
         self.axes_d = axes_d = [end_pos[i] - start_pos[i] for i in (0, 1, 2, 3)]
-        if axes_d[2]:
-            # Move with Z
-            move_d = math.sqrt(sum([d*d for d in axes_d[:3]]))
-            self.do_calc_junction = False
-        else:
-            move_d = math.sqrt(axes_d[0]**2 + axes_d[1]**2)
+        self.move_d = move_d = math.sqrt(sum([d*d for d in axes_d[:3]]))
         if not move_d:
             # Extrude only move
-                move_d = abs(axes_d[3])
-                if not move_d:
-                    # No move
-                    self.move_d = 0.
-                    return
-                self.do_calc_junction = False
-        self.move_d = move_d
-        self.extrude_r = axes_d[3] / move_d
-        # Junction speeds are velocities squared.  The junction_delta
-        # is the maximum amount of this squared-velocity that can
-        # change in this move.
-        self.junction_max = speed**2
-        self.junction_delta = 2.0 * move_d * accel
-        self.junction_start_max = 0.
+            self.move_d = move_d = abs(axes_d[3])
+            self.is_kinematic_move = False
+        self.min_move_t = move_d / speed
+        # Junction speeds are tracked in velocity squared.  The
+        # delta_v2 is the maximum amount of this squared-velocity that
+        # can change in this move.
+        self.max_start_v2 = 0.
+        self.max_cruise_v2 = speed**2
+        self.delta_v2 = 2.0 * move_d * self.accel
+        self.max_smoothed_v2 = 0.
+        self.smooth_delta_v2 = 2.0 * move_d * toolhead.max_accel_to_decel
     def limit_speed(self, speed, accel):
-        self.junction_max = min(self.junction_max, speed**2)
+        speed2 = speed**2
+        if speed2 < self.max_cruise_v2:
+            self.max_cruise_v2 = speed2
+            self.min_move_t = self.move_d / speed
         self.accel = min(self.accel, accel)
-        self.junction_delta = 2.0 * self.move_d * self.accel
+        self.delta_v2 = 2.0 * self.move_d * self.accel
+        self.smooth_delta_v2 = min(self.smooth_delta_v2, self.delta_v2)
     def calc_junction(self, prev_move):
-        if not self.do_calc_junction or not prev_move.do_calc_junction:
+        axes_d = self.axes_d
+        prev_axes_d = prev_move.axes_d
+        if (axes_d[2] or prev_axes_d[2] or self.accel != prev_move.accel
+            or not self.is_kinematic_move or not prev_move.is_kinematic_move):
             return
-        # Find max junction_start_velocity between two moves
-        if (self.extrude_r > prev_move.extrude_r * EXTRUDE_DIFF_IGNORE
-            or prev_move.extrude_r > self.extrude_r * EXTRUDE_DIFF_IGNORE):
-            # Extrude ratio between moves is too different
-            return
-        self.extrude_r = prev_move.extrude_r
+        # Allow extruder to calculate its maximum junction
+        extruder_v2 = self.toolhead.extruder.calc_junction(prev_move, self)
         # Find max velocity using approximated centripetal velocity as
         # described at:
         # https://onehossshay.wordpress.com/2011/09/24/improving_grbl_cornering_algorithm/
-        junction_cos_theta = -((self.axes_d[0] * prev_move.axes_d[0]
-                                + self.axes_d[1] * prev_move.axes_d[1])
+        junction_cos_theta = -((axes_d[0] * prev_axes_d[0]
+                                + axes_d[1] * prev_axes_d[1])
                                / (self.move_d * prev_move.move_d))
         if junction_cos_theta > 0.999999:
             return
         junction_cos_theta = max(junction_cos_theta, -0.999999)
         sin_theta_d2 = math.sqrt(0.5*(1.0-junction_cos_theta))
         R = self.toolhead.junction_deviation * sin_theta_d2 / (1. - sin_theta_d2)
-        self.junction_start_max = min(
-            R * self.accel, self.junction_max, prev_move.junction_max
-            , prev_move.junction_start_max + prev_move.junction_delta)
-    def process(self, junction_start, junction_cruise, junction_end
-                , cornering_min, cornering_max):
+        self.max_start_v2 = min(
+            R * self.accel, self.max_cruise_v2, prev_move.max_cruise_v2
+            , extruder_v2, prev_move.max_start_v2 + prev_move.delta_v2)
+        self.max_smoothed_v2 = min(
+            self.max_start_v2
+            , prev_move.max_smoothed_v2 + prev_move.smooth_delta_v2)
+    def set_junction(self, start_v2, cruise_v2, end_v2):
         # Determine accel, cruise, and decel portions of the move distance
-        inv_junction_delta = 1. / self.junction_delta
-        accel_r = (junction_cruise-junction_start) * inv_junction_delta
-        decel_r = (junction_cruise-junction_end) * inv_junction_delta
-        cruise_r = 1. - accel_r - decel_r
-        self.accel_r, self.cruise_r, self.decel_r = accel_r, cruise_r, decel_r
+        inv_delta_v2 = 1. / self.delta_v2
+        self.accel_r = accel_r = (cruise_v2 - start_v2) * inv_delta_v2
+        self.decel_r = decel_r = (cruise_v2 - end_v2) * inv_delta_v2
+        self.cruise_r = cruise_r = 1. - accel_r - decel_r
         # Determine move velocities
-        start_v = math.sqrt(junction_start)
-        cruise_v = math.sqrt(junction_cruise)
-        end_v = math.sqrt(junction_end)
-        self.start_v, self.cruise_v, self.end_v = start_v, cruise_v, end_v
-        self.corner_min = math.sqrt(cornering_min)
-        self.corner_max = math.sqrt(cornering_max)
+        self.start_v = start_v = math.sqrt(start_v2)
+        self.cruise_v = cruise_v = math.sqrt(cruise_v2)
+        self.end_v = end_v = math.sqrt(end_v2)
         # Determine time spent in each portion of move (time is the
         # distance divided by average velocity)
-        accel_t = accel_r * self.move_d / ((start_v + cruise_v) * 0.5)
-        cruise_t = cruise_r * self.move_d / cruise_v
-        decel_t = decel_r * self.move_d / ((end_v + cruise_v) * 0.5)
-        self.accel_t, self.cruise_t, self.decel_t = accel_t, cruise_t, decel_t
+        self.accel_t = accel_r * self.move_d / ((start_v + cruise_v) * 0.5)
+        self.cruise_t = cruise_r * self.move_d / cruise_v
+        self.decel_t = decel_r * self.move_d / ((end_v + cruise_v) * 0.5)
+    def move(self):
         # Generate step times for the move
         next_move_time = self.toolhead.get_next_move_time()
+        if self.is_kinematic_move:
             self.toolhead.kin.move(next_move_time, self)
         if self.axes_d[3]:
             self.toolhead.extruder.move(next_move_time, self)
-        self.toolhead.update_move_time(accel_t + cruise_t + decel_t)
+        self.toolhead.update_move_time(
+            self.accel_t + self.cruise_t + self.decel_t)
+
+LOOKAHEAD_FLUSH_TIME = 0.250
 
 # Class to track a list of pending move requests and to facilitate
 # "look-ahead" across moves to reduce acceleration between moves.
 class MoveQueue:
-    def __init__(self):
+    def __init__(self, extruder_lookahead):
+        self.extruder_lookahead = extruder_lookahead
         self.queue = []
-        self.junction_flush = 0.
+        self.leftover = 0
+        self.junction_flush = LOOKAHEAD_FLUSH_TIME
     def reset(self):
         del self.queue[:]
+        self.leftover = 0
+        self.junction_flush = LOOKAHEAD_FLUSH_TIME
+    def set_flush_time(self, flush_time):
+        self.junction_flush = flush_time
     def flush(self, lazy=False):
-        flush_count = len(self.queue)
-        move_info = [None] * flush_count
+        self.junction_flush = LOOKAHEAD_FLUSH_TIME
+        update_flush_count = lazy
+        queue = self.queue
+        flush_count = len(queue)
         # Traverse queue from last to first move and determine maximum
         # junction speed assuming the robot comes to a complete stop
         # after the last move.
-        next_junction_end = cornering_min = cornering_max = 0.
-        for i in range(flush_count-1, -1, -1):
-            move = self.queue[i]
-            reachable_start = next_junction_end + move.junction_delta
-            junction_start = min(move.junction_start_max, reachable_start)
-            junction_cruise = min((junction_start + reachable_start) * .5
-                                  , move.junction_max)
-            move_info[i] = (junction_start, junction_cruise, next_junction_end
-                            , cornering_min, cornering_max)
-            if reachable_start > junction_start:
-                cornering_min = junction_start
-                if junction_start + move.junction_delta > next_junction_end:
-                    cornering_max = junction_cruise
-                    if lazy:
+        delayed = []
+        next_end_v2 = next_smoothed_v2 = peak_cruise_v2 = 0.
+        for i in range(flush_count-1, self.leftover-1, -1):
+            move = queue[i]
+            reachable_start_v2 = next_end_v2 + move.delta_v2
+            start_v2 = min(move.max_start_v2, reachable_start_v2)
+            reachable_smoothed_v2 = next_smoothed_v2 + move.smooth_delta_v2
+            smoothed_v2 = min(move.max_smoothed_v2, reachable_smoothed_v2)
+            if smoothed_v2 < reachable_smoothed_v2:
+                # It's possible for this move to accelerate
+                if (smoothed_v2 + move.smooth_delta_v2 > next_smoothed_v2
+                    or delayed):
+                    # This move can decelerate or this is a full accel
+                    # move after a full decel move
+                    if update_flush_count and peak_cruise_v2:
                         flush_count = i
-                        lazy = False
-            next_junction_end = junction_start
-        if lazy:
-            flush_count = 0
+                        update_flush_count = False
+                    peak_cruise_v2 = min(move.max_cruise_v2, (
+                        smoothed_v2 + reachable_smoothed_v2) * .5)
+                    if delayed:
+                        # Propagate peak_cruise_v2 to any delayed moves
+                        if not update_flush_count and i < flush_count:
+                            for m, ms_v2, me_v2 in delayed:
+                                mc_v2 = min(peak_cruise_v2, ms_v2)
+                                m.set_junction(min(ms_v2, mc_v2), mc_v2
+                                               , min(me_v2, mc_v2))
+                        del delayed[:]
+                if not update_flush_count and i < flush_count:
+                    cruise_v2 = min((start_v2 + reachable_start_v2) * .5
+                                    , move.max_cruise_v2, peak_cruise_v2)
+                    move.set_junction(min(start_v2, cruise_v2), cruise_v2
+                                      , min(next_end_v2, cruise_v2))
+            else:
+                # Delay calculating this move until peak_cruise_v2 is known
+                delayed.append((move, start_v2, next_end_v2))
+            next_end_v2 = start_v2
+            next_smoothed_v2 = smoothed_v2
+        if update_flush_count:
+            return
+        # Allow extruder to do its lookahead
+        move_count = self.extruder_lookahead(queue, flush_count, lazy)
         # Generate step times for all moves ready to be flushed
-        for i in range(flush_count):
-            self.queue[i].process(*move_info[i])
+        for move in queue[:move_count]:
+            move.move()
         # Remove processed moves from the queue
-        del self.queue[:flush_count]
-        if self.queue:
-            self.junction_flush = 2. * self.queue[-1].junction_max
+        self.leftover = flush_count - move_count
+        del queue[:move_count]
     def add_move(self, move):
         self.queue.append(move)
         if len(self.queue) == 1:
-            self.junction_flush = 2. * move.junction_max
             return
         move.calc_junction(self.queue[-2])
-        self.junction_flush -= move.junction_delta
+        self.junction_flush -= move.min_move_t
         if self.junction_flush <= 0.:
             # There are enough queued moves to return to zero velocity
             # from the first move's maximum possible velocity, so at
@@ -159,58 +182,94 @@ class ToolHead:
         self.printer = printer
         self.reactor = printer.reactor
         self.extruder = printer.objects.get('extruder')
+        if self.extruder is None:
+            self.extruder = extruder.DummyExtruder()
         kintypes = {'cartesian': cartesian.CartKinematics,
+                    'corexy': corexy.CoreXYKinematics,
                     'delta': delta.DeltaKinematics}
         self.kin = config.getchoice('kinematics', kintypes)(printer, config)
-        self.max_speed = config.getfloat('max_velocity')
-        self.max_accel = config.getfloat('max_accel')
-        self.junction_deviation = config.getfloat('junction_deviation', 0.02)
-        self.move_queue = MoveQueue()
+        self.max_speed = config.getfloat('max_velocity', above=0.)
+        self.max_accel = config.getfloat('max_accel', above=0.)
+        self.max_accel_to_decel = config.getfloat(
+            'max_accel_to_decel', self.max_accel * 0.5
+            , above=0., maxval=self.max_accel)
+        self.junction_deviation = config.getfloat(
+            'junction_deviation', 0.02, above=0.)
+        self.move_queue = MoveQueue(self.extruder.lookahead)
         self.commanded_pos = [0., 0., 0., 0.]
         # Print time tracking
-        self.buffer_time_high = config.getfloat('buffer_time_high', 5.000)
-        self.buffer_time_low = config.getfloat('buffer_time_low', 0.150)
-        self.move_flush_time = config.getfloat('move_flush_time', 0.050)
-        self.motor_off_delay = config.getfloat('motor_off_time', 60.000)
+        self.buffer_time_low = config.getfloat(
+            'buffer_time_low', 1.000, above=0.)
+        self.buffer_time_high = config.getfloat(
+            'buffer_time_high', 2.000, above=self.buffer_time_low)
+        self.buffer_time_start = config.getfloat(
+            'buffer_time_start', 0.250, above=0.)
+        self.move_flush_time = config.getfloat(
+            'move_flush_time', 0.050, above=0.)
         self.print_time = 0.
+        self.last_print_end_time = self.reactor.monotonic()
         self.need_check_stall = -1.
-        self.print_time_stall = 0
-        self.motor_off_time = self.reactor.NEVER
+        self.print_stall = 0
+        self.synch_print_time = True
+        self.forced_synch = False
         self.flush_timer = self.reactor.register_timer(self._flush_handler)
-    def build_config(self):
-        self.kin.set_max_jerk(0.005 * self.max_accel, self.max_accel) # XXX
-        self.kin.build_config()
+        self.move_queue.set_flush_time(self.buffer_time_high)
+        # Motor off tracking
+        self.motor_off_time = config.getfloat(
+            'motor_off_time', 600.000, minval=0.)
+        self.motor_off_timer = self.reactor.register_timer(
+            self._motor_off_handler)
+        # Determine the maximum velocity a cartesian axis could have
+        # before cornering.  The 8. was determined experimentally.
+        xy_halt = math.sqrt(8. * self.junction_deviation * self.max_accel)
+        self.kin.set_max_jerk(xy_halt, self.max_speed, self.max_accel)
+        self.extruder.set_max_jerk(xy_halt, self.max_speed, self.max_accel)
     # Print time tracking
     def update_move_time(self, movetime):
         self.print_time += movetime
         flush_to_time = self.print_time - self.move_flush_time
         self.printer.mcu.flush_moves(flush_to_time)
     def get_next_move_time(self):
-        if not self.print_time:
-            self.print_time = self.buffer_time_low + STALL_TIME
-            curtime = time.time()
+        if self.synch_print_time:
+            curtime = self.reactor.monotonic()
+            if self.print_time:
+                buffer_time = self.printer.mcu.get_print_buffer_time(
+                    curtime, self.print_time)
+                self.print_time += max(self.buffer_time_start - buffer_time, 0.)
+                if self.forced_synch:
+                    self.print_stall += 1
+                    self.forced_synch = False
+            else:
                 self.printer.mcu.set_print_start_time(curtime)
+                self.print_time = self.buffer_time_start
+                self._reset_motor_off()
             self.reactor.update_timer(self.flush_timer, self.reactor.NOW)
+            self.synch_print_time = False
         return self.print_time
-    def get_last_move_time(self):
-        self.move_queue.flush()
-        return self.get_next_move_time()
-    def reset_motor_off_time(self, eventtime):
-        self.motor_off_time = eventtime + self.motor_off_delay
-    def reset_print_time(self):
+    def _flush_lookahead(self, must_synch=False):
+        synch_print_time = self.synch_print_time
         self.move_queue.flush()
+        if synch_print_time or must_synch:
+            self.synch_print_time = True
+            self.move_queue.set_flush_time(self.buffer_time_high)
             self.printer.mcu.flush_moves(self.print_time)
+    def get_last_move_time(self):
+        self._flush_lookahead()
+        return self.get_next_move_time()
+    def reset_print_time(self):
+        self._flush_lookahead(must_synch=True)
         self.print_time = 0.
+        self.last_print_end_time = self.reactor.monotonic()
         self.need_check_stall = -1.
-        self.reset_motor_off_time(time.time())
-        self.reactor.update_timer(self.flush_timer, self.motor_off_time)
+        self.forced_synch = False
+        self._reset_motor_off()
     def _check_stall(self):
+        eventtime = self.reactor.monotonic()
         if not self.print_time:
-            # XXX - find better way to flush initial move_queue items
-            if self.move_queue.queue:
-                self.reactor.update_timer(self.flush_timer, time.time() + 0.100)
+            # Building initial queue - make sure to flush on idle input
+            self.reactor.update_timer(self.flush_timer, eventtime + 0.100)
             return
-        eventtime = time.time()
+        # Check if there are lots of queued moves and stall if so
         while 1:
             buffer_time = self.printer.mcu.get_print_buffer_time(
                 eventtime, self.print_time)
@@ -224,47 +283,58 @@ class ToolHead:
     def _flush_handler(self, eventtime):
         try:
             if not self.print_time:
-                self.move_queue.flush()
+                # Input idled before filling lookahead queue - flush it
+                self._flush_lookahead()
                 if not self.print_time:
-                    if eventtime >= self.motor_off_time:
-                        self.motor_off()
-                        self.reset_print_time()
-                        self.motor_off_time = self.reactor.NEVER
-                    return self.motor_off_time
+                    return self.reactor.NEVER
             print_time = self.print_time
             buffer_time = self.printer.mcu.get_print_buffer_time(
                 eventtime, print_time)
             if buffer_time > self.buffer_time_low:
+                # Running normally - reschedule check
                 return eventtime + buffer_time - self.buffer_time_low
-            self.move_queue.flush()
+            # Under ran low buffer mark - flush lookahead queue
+            self._flush_lookahead(must_synch=True)
             if print_time != self.print_time:
-                self.print_time_stall += 1
-                self.dwell(self.buffer_time_low + STALL_TIME)
+                # Flushed something - retry
+                self.forced_synch = True
                 return self.reactor.NOW
+            if buffer_time > 0.:
+                # Wait for buffer to fully empty
+                return eventtime + buffer_time
             self.reset_print_time()
-            return self.motor_off_time
         except:
             logging.exception("Exception in flush_handler")
             self.force_shutdown()
-    def stats(self, eventtime):
-        buffer_time = 0.
-        if self.print_time:
-            buffer_time = self.printer.mcu.get_print_buffer_time(
-                eventtime, self.print_time)
-        return "print_time=%.3f buffer_time=%.3f print_time_stall=%d" % (
-            self.print_time, buffer_time, self.print_time_stall)
+        return self.reactor.NEVER
+    # Motor off timer
+    def _reset_motor_off(self):
+        if not self.print_time:
+            waketime = self.reactor.monotonic() + self.motor_off_time
+        else:
+            waketime = self.reactor.NEVER
+        self.reactor.update_timer(self.motor_off_timer, waketime)
+    def _motor_off_handler(self, eventtime):
+        try:
+            self.motor_off()
+            self.reset_print_time()
+        except:
+            logging.exception("Exception in motor_off_handler")
+            self.force_shutdown()
+        return self.reactor.NEVER
     # Movement commands
     def get_position(self):
         return list(self.commanded_pos)
     def set_position(self, newpos):
-        self.move_queue.flush()
+        self._flush_lookahead()
         self.commanded_pos[:] = newpos
         self.kin.set_position(newpos)
     def move(self, newpos, speed):
         speed = min(speed, self.max_speed)
-        move = Move(self, self.commanded_pos, newpos, speed, self.max_accel)
+        move = Move(self, self.commanded_pos, newpos, speed)
         if not move.move_d:
             return
+        if move.is_kinematic_move:
             self.kin.check_move(move)
         if move.axes_d[3]:
             self.extruder.check_move(move)
@@ -285,9 +355,30 @@ class ToolHead:
         self.extruder.motor_off(last_move_time)
         self.dwell(STALL_TIME)
         logging.debug('; Max time of %f' % (last_move_time,))
+    def wait_moves(self):
+        self._flush_lookahead()
+        eventtime = self.reactor.monotonic()
+        while self.print_time:
+            eventtime = self.reactor.pause(eventtime + 0.100)
     def query_endstops(self):
         last_move_time = self.get_last_move_time()
         return self.kin.query_endstops(last_move_time)
+    # Misc commands
+    def stats(self, eventtime):
+        buffer_time = 0.
+        print_time = self.print_time
+        if print_time:
+            is_active = True
+            buffer_time = max(0., self.printer.mcu.get_print_buffer_time(
+                eventtime, print_time))
+        else:
+            is_active = eventtime < self.last_print_end_time + 60.
+        return is_active, "print_time=%.3f buffer_time=%.3f print_stall=%d" % (
+            print_time, buffer_time, self.print_stall)
     def force_shutdown(self):
+        try:
             self.printer.mcu.force_shutdown()
             self.move_queue.reset()
+            self.reset_print_time()
+        except:
+            logging.exception("Exception in force_shutdown")

klippy/util.py

@@ -3,8 +3,8 @@
 # Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-
-import os, pty, fcntl, termios, signal
+import sys, os, pty, fcntl, termios, signal, logging
+import subprocess, traceback, shlex
 
 # Return the SIGINT interrupt handler back to the OS default
 def fix_sigint():
@@ -36,3 +36,34 @@ def create_pty(ptyname):
     old[3] = old[3] & ~termios.ECHO
     termios.tcsetattr(mfd, termios.TCSADRAIN, old)
     return mfd
+
+def get_cpu_info():
+    try:
+        f = open('/proc/cpuinfo', 'rb')
+        data = f.read()
+        f.close()
+    except OSError:
+        logging.debug("Exception on read /proc/cpuinfo: %s" % (
+            traceback.format_exc(),))
+        return "?"
+    lines = [l.split(':', 1) for l in data.split('\n')]
+    lines = [(l[0].strip(), l[1].strip()) for l in lines if len(l) == 2]
+    core_count = [k for k, v in lines].count("processor")
+    model_name = dict(lines).get("model name", "?")
+    return "%d core %s" % (core_count, model_name)
+
+def get_git_version():
+    # Obtain version info from "git" program
+    gitdir = os.path.join(sys.path[0], '..', '.git')
+    if not os.path.exists(gitdir):
+        logging.debug("No '.git' file/directory found")
+        return "?"
+    prog = "git --git-dir=%s describe --tags --long --dirty" % (gitdir,)
+    try:
+        process = subprocess.Popen(shlex.split(prog), stdout=subprocess.PIPE)
+        output = process.communicate()[0]
+        retcode = process.poll()
+    except OSError:
+        logging.debug("Exception on run: %s" % (traceback.format_exc(),))
+        return "?"
+    return output.strip()

lib/README

@@ -10,3 +10,7 @@ The cmsis-sam3x8e directory contains code from the Arduino project:
 version 1.5.1 (extracted on 20160608).  It has been modified to
 compile with gcc's LTO feature. See cmsis-sam3x8e.patch for the
 modifications.
+
+The hub-ctrl directory contains code from:
+  https://github.com/codazoda/hub-ctrl.c/
+revision 42095e522859059e8a5f4ec05c1e3def01a870a9.

lib/hub-ctrl/hub-ctrl.c

@@ -0,0 +1,412 @@
+/*
+ * Copyright (C) 2006 Free Software Initiative of Japan
+ *
+ * Author: NIIBE Yutaka  <gniibe at fsij.org>
+ *
+ * This file can be distributed under the terms and conditions of the
+ * GNU General Public License version 2 (or later).
+ *
+ */
+
+#include <errno.h>
+#include <usb.h>
+#include <stdio.h>
+#include <string.h>
+
+#define USB_RT_HUB			(USB_TYPE_CLASS | USB_RECIP_DEVICE)
+#define USB_RT_PORT			(USB_TYPE_CLASS | USB_RECIP_OTHER)
+#define USB_PORT_FEAT_POWER		8
+#define USB_PORT_FEAT_INDICATOR         22
+#define USB_DIR_IN			0x80		/* to host */
+
+#define COMMAND_SET_NONE  0
+#define COMMAND_SET_LED   1
+#define COMMAND_SET_POWER 2
+#define HUB_LED_GREEN 2
+
+static void
+usage (const char *progname)
+{
+  fprintf (stderr,
+	   "Usage: %s [{-h HUBNUM | -b BUSNUM -d DEVNUM}] \\\n"
+	   "          [-P PORT] [{-p [VALUE]|-l [VALUE]}]\n", progname);
+}
+
+static void
+exit_with_usage (const char *progname)
+{
+  usage (progname);
+  exit (1);
+}
+
+#define HUB_CHAR_LPSM		0x0003
+#define HUB_CHAR_PORTIND        0x0080
+
+struct usb_hub_descriptor {
+  unsigned char bDescLength;
+  unsigned char bDescriptorType;
+  unsigned char bNbrPorts;
+  unsigned char wHubCharacteristics[2];
+  unsigned char bPwrOn2PwrGood;
+  unsigned char bHubContrCurrent;
+  unsigned char data[0];
+};
+
+#define CTRL_TIMEOUT 1000
+#define USB_STATUS_SIZE 4
+
+#define MAX_HUBS 128
+struct hub_info {
+  int busnum, devnum;
+  struct usb_device *dev;
+  int nport;
+  int indicator_support;
+};
+
+static struct hub_info hubs[MAX_HUBS];
+static int number_of_hubs_with_feature;
+
+static void
+hub_port_status (usb_dev_handle *uh, int nport)
+{
+  int i;
+
+  printf(" Hub Port Status:\n");
+  for (i = 0; i < nport; i++)
+    {
+      char buf[USB_STATUS_SIZE];
+      int ret;
+
+      ret = usb_control_msg (uh,
+			     USB_ENDPOINT_IN | USB_TYPE_CLASS | USB_RECIP_OTHER,
+			     USB_REQ_GET_STATUS, 
+			     0, i + 1,
+			     buf, USB_STATUS_SIZE,
+			     CTRL_TIMEOUT);
+      if (ret < 0)
+	{
+	  fprintf (stderr,
+		   "cannot read port %d status, %s (%d)\n",
+		   i + 1, strerror(errno), errno);
+	  break;
+	}
+
+      printf("   Port %d: %02x%02x.%02x%02x", i + 1,
+	     buf[3], buf [2],
+	     buf[1], buf [0]);
+
+      printf("%s%s%s%s%s",
+	     (buf[2] & 0x10) ? " C_RESET" : "",
+	     (buf[2] & 0x08) ? " C_OC" : "",
+	     (buf[2] & 0x04) ? " C_SUSPEND" : "",
+	     (buf[2] & 0x02) ? " C_ENABLE" : "",
+	     (buf[2] & 0x01) ? " C_CONNECT" : "");
+
+      printf("%s%s%s%s%s%s%s%s%s%s\n",
+	     (buf[1] & 0x10) ? " indicator" : "",
+	     (buf[1] & 0x08) ? " test" : "",
+	     (buf[1] & 0x04) ? " highspeed" : "",
+	     (buf[1] & 0x02) ? " lowspeed" : "",
+	     (buf[1] & 0x01) ? " power" : "",
+	     (buf[0] & 0x10) ? " RESET" : "",
+	     (buf[0] & 0x08) ? " oc" : "",
+	     (buf[0] & 0x04) ? " suspend" : "",
+	     (buf[0] & 0x02) ? " enable" : "",
+	     (buf[0] & 0x01) ? " connect" : "");
+    }
+}
+
+static int
+usb_find_hubs (int listing, int verbose, int busnum, int devnum, int hub)
+{
+  struct usb_bus *busses;
+  struct usb_bus *bus;
+
+  number_of_hubs_with_feature = 0;
+  busses = usb_get_busses();
+  if (busses == NULL)
+    {
+      perror ("failed to access USB");
+      return -1;
+    }
+
+  for (bus = busses; bus; bus = bus->next)
+    {
+      struct usb_device *dev;
+
+      for (dev = bus->devices; dev; dev = dev->next)
+	{
+	  usb_dev_handle *uh;
+	  int print = 0;
+
+	  if (dev->descriptor.bDeviceClass != USB_CLASS_HUB)
+	    continue;
+
+	  if (listing
+	      || (verbose
+		  && ((atoi (bus->dirname) == busnum && dev->devnum == devnum)
+		      || hub == number_of_hubs_with_feature)))
+	    print = 1;
+
+	  uh = usb_open (dev);
+
+	  if (uh != NULL)
+	    {
+	      char buf[1024];
+	      int len;
+	      int nport;
+	      struct usb_hub_descriptor *uhd = (struct usb_hub_descriptor *)buf;
+	      if ((len = usb_control_msg (uh, USB_DIR_IN | USB_RT_HUB,
+					  USB_REQ_GET_DESCRIPTOR,
+					  USB_DT_HUB << 8, 0, 
+					  buf, sizeof (buf), CTRL_TIMEOUT))
+		  > sizeof (struct usb_hub_descriptor))
+		{
+		  if (!(uhd->wHubCharacteristics[0] & HUB_CHAR_PORTIND)
+		      && (uhd->wHubCharacteristics[0] & HUB_CHAR_LPSM) >= 2)
+		    continue;
+
+		  if (print)
+		    printf ("Hub #%d at %s:%03d\n",
+			    number_of_hubs_with_feature,
+			    bus->dirname, dev->devnum);
+
+		  switch ((uhd->wHubCharacteristics[0] & HUB_CHAR_LPSM))
+		    {
+		    case 0:
+		      if (print)
+			fprintf (stderr, " INFO: ganged switching.\n");
+		      break;
+		    case 1:
+		      if (print)
+			fprintf (stderr, " INFO: individual power switching.\n");
+		      break;
+		    case 2:
+		    case 3:
+		      if (print)
+			fprintf (stderr, " WARN: No power switching.\n");
+		      break;
+		    }
+
+		  if (print
+		      && !(uhd->wHubCharacteristics[0] & HUB_CHAR_PORTIND))
+		    fprintf (stderr, " WARN: Port indicators are NOT supported.\n");
+		}
+	      else
+		{
+		  perror ("Can't get hub descriptor");
+		  usb_close (uh);
+		  continue;
+		}
+
+	      nport = buf[2];
+	      hubs[number_of_hubs_with_feature].busnum = atoi (bus->dirname);
+	      hubs[number_of_hubs_with_feature].devnum = dev->devnum;
+	      hubs[number_of_hubs_with_feature].dev = dev;
+	      hubs[number_of_hubs_with_feature].indicator_support =
+		(uhd->wHubCharacteristics[0] & HUB_CHAR_PORTIND)? 1 : 0;
+	      hubs[number_of_hubs_with_feature].nport = nport;
+
+	      number_of_hubs_with_feature++;
+
+	      if (verbose)
+		hub_port_status (uh, nport);
+
+	      usb_close (uh);
+	    }
+	}
+    }
+
+  return number_of_hubs_with_feature;
+}
+
+int
+get_hub (int busnum, int devnum)
+{
+  int i;
+
+  for (i = 0; i < number_of_hubs_with_feature; i++)
+    if (hubs[i].busnum == busnum && hubs[i].devnum == devnum)
+      return i;
+
+  return -1;
+}
+
+/*
+ * HUB-CTRL  -  program to control port power/led of USB hub
+ *
+ *   # hub-ctrl                    // List hubs available
+ *   # hub-ctrl -P 1               // Power off at port 1
+ *   # hub-ctrl -P 1 -p 1          // Power on at port 1
+ *   # hub-ctrl -P 2 -l            // LED on at port 1
+ *
+ * Requirement: USB hub which implements port power control / indicator control
+ *
+ *      Work fine:
+ *         Elecom's U2H-G4S: www.elecom.co.jp (indicator depends on power)
+ *         04b4:6560
+ *
+ *	   Sanwa Supply's USB-HUB14GPH: www.sanwa.co.jp (indicators don't)
+ *
+ *	   Targus, Inc.'s PAUH212: www.targus.com (indicators don't)
+ *         04cc:1521
+ *
+ *	   Hawking Technology's UH214: hawkingtech.com (indicators don't)
+ *
+ */
+
+int
+main (int argc, const char *argv[])
+{
+  int busnum = 0, devnum = 0;
+  int cmd = COMMAND_SET_NONE;
+  int port = 1;
+  int value = 0;
+  int request, feature, index;
+  int result = 0;
+  int listing = 0;
+  int verbose = 0;
+  int hub = -1;
+  usb_dev_handle *uh = NULL;
+  int i;
+
+  if (argc == 1)
+    listing = 1;
+
+  for (i = 1; i < argc; i++)
+    if (argv[i][0] == '-')
+      switch (argv[i][1])
+	{
+	case 'h':
+	  if (++i >= argc || busnum > 0 || devnum > 0)
+	    exit_with_usage (argv[0]);
+	  hub = atoi (argv[i]);
+	  break;
+
+	case 'b':
+	  if (++i >= argc || hub >= 0)
+	    exit_with_usage (argv[0]);
+	  busnum = atoi (argv[i]);
+	  break;
+
+	case 'd':
+	  if (++i >= argc || hub >= 0)
+	    exit_with_usage (argv[0]);
+	  devnum = atoi (argv[i]);
+	  break;
+
+	case 'P':
+	  if (++i >= argc)
+	    exit_with_usage (argv[0]);
+	  port = atoi (argv[i]);
+	  break;
+
+	case 'l':
+	  if (cmd != COMMAND_SET_NONE)
+	    exit_with_usage (argv[0]);
+	  if (++i < argc)
+	    value = atoi (argv[i]);
+	  else
+	    value = HUB_LED_GREEN;
+	  cmd = COMMAND_SET_LED;
+	  break;
+
+	case 'p':
+	  if (cmd != COMMAND_SET_NONE)
+	    exit_with_usage (argv[0]);
+	  if (++i < argc)
+	    value = atoi (argv[i]);
+	  else
+	    value= 0;
+	  cmd = COMMAND_SET_POWER;
+	  break;
+
+	case 'v':
+	  verbose = 1;
+	  if (argc == 2)
+	    listing = 1;
+	  break;
+
+	default:
+	  exit_with_usage (argv[0]);
+	}
+    else
+      exit_with_usage (argv[0]);
+
+  if ((busnum > 0 && devnum <= 0) || (busnum <= 0 && devnum > 0))
+    /* BUS is specified, but DEV is'nt, or ... */
+    exit_with_usage (argv[0]);
+
+  /* Default is the hub #0 */
+  if (hub < 0 && busnum == 0)
+    hub = 0;
+
+  /* Default is POWER */
+  if (cmd == COMMAND_SET_NONE)
+    cmd = COMMAND_SET_POWER;
+
+  usb_init ();
+  usb_find_busses ();
+  usb_find_devices ();
+
+  if (usb_find_hubs (listing, verbose, busnum, devnum, hub) <= 0)
+    {
+      fprintf (stderr, "No hubs found.\n");
+      exit (1);
+    }
+
+  if (listing)
+    exit (0);
+
+  if (hub < 0)
+    hub = get_hub (busnum, devnum);
+
+  if (hub >= 0 && hub < number_of_hubs_with_feature)
+    uh = usb_open (hubs[hub].dev);
+
+  if (uh == NULL)
+    {
+      fprintf (stderr, "Device not found.\n");
+      result = 1;
+    }
+  else
+    {
+      if (cmd == COMMAND_SET_POWER)
+	if (value)
+	  {
+	    request = USB_REQ_SET_FEATURE;
+	    feature = USB_PORT_FEAT_POWER;
+	    index = port;
+	  }
+	else
+	  {
+	    request = USB_REQ_CLEAR_FEATURE;
+	    feature = USB_PORT_FEAT_POWER;
+	    index = port;
+	  }
+      else
+	{
+	  request = USB_REQ_SET_FEATURE;
+	  feature = USB_PORT_FEAT_INDICATOR;
+	  index = (value << 8) | port;
+	}
+
+      if (verbose)
+	printf ("Send control message (REQUEST=%d, FEATURE=%d, INDEX=%d)\n",
+		request, feature, index);
+
+      if (usb_control_msg (uh, USB_RT_PORT, request, feature, index,
+			   NULL, 0, CTRL_TIMEOUT) < 0)
+	{
+	  perror ("failed to control.\n");
+	  result = 1;
+	}
+
+      if (verbose)
+	hub_port_status (uh, hubs[hub].nport);
+
+      usb_close (uh);
+    }
+
+  exit (result);
+}

scripts/avrsim.py

@@ -5,21 +5,22 @@
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 
-import sys, optparse, os, pty, select, fcntl, termios, traceback, errno
+import sys, optparse, time, os, pty, fcntl, termios, errno
 import pysimulavr
 
 SERIALBITS = 10 # 8N1 = 1 start, 8 data, 1 stop
+SIMULAVR_FREQ = 10**9
 
 # Class to read serial data from AVR serial transmit pin.
 class SerialRxPin(pysimulavr.PySimulationMember, pysimulavr.Pin):
-    def __init__(self, baud):
+    def __init__(self, baud, terminal):
         pysimulavr.Pin.__init__(self)
         pysimulavr.PySimulationMember.__init__(self)
+        self.terminal = terminal
         self.sc = pysimulavr.SystemClock.Instance()
-        self.delay = 10**9 / baud
+        self.delay = SIMULAVR_FREQ / baud
         self.current = 0
         self.pos = -1
-        self.queue = ""
     def SetInState(self, pin):
         pysimulavr.Pin.SetInState(self, pin)
         self.state = pin.outState
@@ -33,32 +34,33 @@ class SerialRxPin(pysimulavr.PySimulationMember, pysimulavr.Pin):
         if self.pos == 1:
             return int(self.delay * 1.5)
         if self.pos >= SERIALBITS:
-            self.queue += chr((self.current >> 1) & 0xff)
+            data = chr((self.current >> 1) & 0xff)
+            self.terminal.write(data)
             self.pos = -1
             self.current = 0
             return -1
         return self.delay
-    def popChars(self):
-        d = self.queue
-        self.queue = ""
-        return d
 
 # Class to send serial data to AVR serial receive pin.
 class SerialTxPin(pysimulavr.PySimulationMember, pysimulavr.Pin):
-    MAX_QUEUE = 64
-    def __init__(self, baud):
+    def __init__(self, baud, terminal):
         pysimulavr.Pin.__init__(self)
         pysimulavr.PySimulationMember.__init__(self)
+        self.terminal = terminal
         self.SetPin('H')
         self.sc = pysimulavr.SystemClock.Instance()
-        self.delay = 10**9 / baud
+        self.delay = SIMULAVR_FREQ / baud
         self.current = 0
         self.pos = 0
         self.queue = ""
+        self.sc.Add(self)
     def DoStep(self, trueHwStep):
         if not self.pos:
             if not self.queue:
-                return -1
+                data = self.terminal.read()
+                if not data:
+                    return self.delay * 100
+                self.queue += data
             self.current = (ord(self.queue[0]) << 1) | 0x200
             self.queue = self.queue[1:]
         newstate = 'L'
@@ -69,15 +71,6 @@ class SerialTxPin(pysimulavr.PySimulationMember, pysimulavr.Pin):
         if self.pos >= SERIALBITS:
             self.pos = 0
         return self.delay
-    def needChars(self):
-        if len(self.queue) > self.MAX_QUEUE / 2:
-            return 0
-        return self.MAX_QUEUE - len(self.queue)
-    def pushChars(self, c):
-        queueEmpty = not self.queue
-        self.queue += c
-        if queueEmpty:
-            self.sc.Add(self)
 
 # Support for creating VCD trace files
 class Tracing:
@@ -108,6 +101,47 @@ class Tracing:
         if self.dman is not None:
             self.dman.stopApplication()
 
+# Pace the simulation scaled to real time
+class Pacing(pysimulavr.PySimulationMember):
+    def __init__(self, rate):
+        pysimulavr.PySimulationMember.__init__(self)
+        self.sc = pysimulavr.SystemClock.Instance()
+        self.pacing_rate = 1. / (rate * SIMULAVR_FREQ)
+        self.rel_time = self.next_rel_time = time.time()
+        self.rel_clock = self.next_rel_clock = self.sc.GetCurrentTime()
+        self.delay = SIMULAVR_FREQ / 10000
+        self.sc.Add(self)
+    def DoStep(self, trueHwStep):
+        curtime = time.time()
+        clock = self.sc.GetCurrentTime()
+        clock_diff = clock - self.rel_clock
+        time_diff = curtime - self.rel_time
+        offset = clock_diff * self.pacing_rate - time_diff
+        if offset > 0.000050:
+            time.sleep(offset)
+        if clock_diff > self.delay * 20:
+            self.rel_clock = self.next_rel_clock
+            self.rel_time = self.next_rel_time
+            self.next_rel_clock = clock
+            self.next_rel_time = curtime
+        return self.delay
+
+# Forward data from a terminal device to the serial port pins
+class TerminalIO:
+    def __init__(self):
+        self.fd = -1
+    def run(self, fd):
+        self.fd = fd
+    def write(self, data):
+        os.write(self.fd, data)
+    def read(self):
+        try:
+            return os.read(self.fd, 64)
+        except os.error, e:
+            if e.errno not in (errno.EAGAIN, errno.EWOULDBLOCK):
+                pysimulavr.SystemClock.Instance().stop()
+        return ""
+
 # Support for creating a pseudo-tty for emulating a serial port
 def create_pty(ptyname):
     mfd, sfd = pty.openpty()
@@ -130,6 +164,8 @@ def main():
                     default="atmega644", help="type of AVR machine to simulate")
     opts.add_option("-s", "--speed", type="int", dest="speed", default=8000000,
                     help="machine speed")
+    opts.add_option("-r", "--rate", type="float", dest="pacing_rate", default=0.,
+                    help="real-time pacing rate")
     opts.add_option("-b", "--baud", type="int", dest="baud", default=38400,
                     help="baud rate of the emulated serial port")
     opts.add_option("-t", "--trace", type="string", dest="trace",
@@ -154,18 +190,26 @@ def main():
     trace = Tracing(options.tracefile, options.trace)
     dev = pysimulavr.AvrFactory.instance().makeDevice(proc)
     dev.Load(elffile)
-    dev.SetClockFreq(10**9 / speed)
+    dev.SetClockFreq(SIMULAVR_FREQ / speed)
     sc.Add(dev)
+    pysimulavr.cvar.sysConHandler.SetUseExit(False)
     trace.load_options()
 
+    # Do optional real-time pacing
+    if options.pacing_rate:
+        pacing = Pacing(options.pacing_rate)
+
+    # Setup terminal
+    io = TerminalIO()
+
     # Setup rx pin
-    rxpin = SerialRxPin(baud)
+    rxpin = SerialRxPin(baud, io)
     net = pysimulavr.Net()
     net.Add(rxpin)
     net.Add(dev.GetPin("D1"))
 
     # Setup tx pin
-    txpin = SerialTxPin(baud)
+    txpin = SerialTxPin(baud, io)
     net2 = pysimulavr.Net()
     net2.Add(dev.GetPin("D0"))
     net2.Add(txpin)
@@ -183,27 +227,9 @@ def main():
 
     # Run loop
     try:
+        io.run(fd)
         trace.start()
-        while 1:
-            starttime = sc.GetCurrentTime()
-            r = sc.RunTimeRange(speed/1000)
-            endtime = sc.GetCurrentTime()
-            if starttime == endtime:
-                break
-            d = rxpin.popChars()
-            if d:
-                os.write(fd, d)
-            txsize = txpin.needChars()
-            if txsize:
-                res = select.select([fd], [], [], 0)
-                if res[0]:
-                    try:
-                        d = os.read(fd, txsize)
-                    except os.error, e:
-                        if e.errno in (errno.EAGAIN, errno.EWOULDBLOCK):
-                            continue
-                        break
-                    txpin.pushChars(d)
+        sc.RunTimeRange(0x7fff0000ffff0000)
         trace.finish()
     finally:
         os.unlink(ptyname)

scripts/checkstack.py

@@ -172,6 +172,9 @@ def main():
             if '+' in ref:
                 # Inter-function jump.
                 pass
+            elif insn.startswith('ld') or insn.startswith('st'):
+                # memory access
+                pass
             elif insn in ('rjmp', 'jmp', 'brne', 'brcs'):
                 # Tail call
                 cur.noteCall(insnaddr, calladdr, 0)
@@ -190,7 +193,7 @@ def main():
         funcsbyname[funcnameroot] = info
     mainfunc = funcsbyname.get('sched_main')
     cmdfunc = funcsbyname.get('command_task')
-    eventfunc = funcsbyname.get('__vector_13')
+    eventfunc = funcsbyname.get('__vector_13', funcsbyname.get('__vector_17'))
     for funcnameroot, info in funcsbyname.items():
         if (funcnameroot.startswith('_DECL_taskfuncs_')
             or funcnameroot.startswith('_DECL_initfuncs_')
@@ -204,7 +207,7 @@ def main():
                 numparams = int(datalines[info.funcaddr][2], 16)
                 stackusage = cmdfunc.basic_stack_usage + 2 + numparams * 4
                 cmdfunc.noteCall(0, f.funcaddr, stackusage)
-        if funcnameroot.endswith('_event'):
+        if funcnameroot.endswith('_event') and eventfunc is not None:
             eventfunc.noteCall(0, info.funcaddr, eventfunc.basic_stack_usage + 2)
 
     # Calculate maxstackusage

scripts/graphstats.py

@@ -8,7 +8,7 @@ import optparse, datetime
 import matplotlib.pyplot as plt, matplotlib.dates as mdates
 
 MAXBANDWIDTH=25000.
-MAXBUFFER=5.
+MAXBUFFER=2.
 
 def parse_log(logname):
     f = open(logname, 'rb')
@@ -27,10 +27,32 @@ def parse_log(logname):
     f.close()
     return out
 
+def find_print_restarts(data):
+    last_print_time = 0.
+    print_resets = []
+    for d in data:
+        print_time = float(d.get('print_time', last_print_time))
+        if print_time < last_print_time:
+            print_resets.append(d['#sampletime'])
+            last_print_time = 0.
+        else:
+            last_print_time = print_time
+    sample_resets = {}
+    for d in data:
+        st = d['#sampletime']
+        while print_resets and st > print_resets[0]:
+            print_resets.pop(0)
+        if not print_resets:
+            break
+        if st + 2. * MAXBUFFER > print_resets[0]:
+            sample_resets[st] = 1
+    return sample_resets
+
 def plot_mcu(data, maxbw, outname):
     # Generate data for plot
     basetime = lasttime = data[0]['#sampletime']
     lastbw = float(data[0]['bytes_write']) + float(data[0]['bytes_retransmit'])
+    sample_resets = find_print_restarts(data)
     times = []
     bwdeltas = []
     loads = []
@@ -49,7 +71,7 @@ def plot_mcu(data, maxbw, outname):
             load = 0.
         pt = float(d['print_time'])
         hb = float(d['buffer_time'])
-        if pt <= 2*MAXBUFFER or hb >= MAXBUFFER:
+        if pt <= 2. * MAXBUFFER or hb >= MAXBUFFER or st in sample_resets:
             hb = 0.
         else:
             hb = 100. * (MAXBUFFER - hb) / MAXBUFFER
@@ -63,12 +85,12 @@ def plot_mcu(data, maxbw, outname):
     # Build plot
     fig, ax1 = plt.subplots()
     ax1.set_title("MCU bandwidth and load utilization")
-    ax1.set_xlabel('Time (UTC)')
+    ax1.set_xlabel('Time')
     ax1.set_ylabel('Usage (%)')
     ax1.plot_date(times, bwdeltas, 'g', label='Bandwidth')
     ax1.plot_date(times, loads, 'r', label='MCU load')
-    #ax1.plot_date(times, hostbuffers, 'c', label='Host buffer')
-    ax1.legend()
+    ax1.plot_date(times, hostbuffers, 'c', label='Host buffer')
+    ax1.legend(loc='best')
     ax1.xaxis.set_major_formatter(mdates.DateFormatter('%H:%M'))
     #plt.gcf().autofmt_xdate()
     ax1.grid(True)

scripts/install-octopi.sh

@@ -0,0 +1,102 @@
+#!/bin/bash
+# This script installs Klipper on a Raspberry Pi machine running the
+# OctoPi distribution.
+
+PYTHONDIR="${HOME}/klippy-env"
+
+# Step 1: Install system packages
+install_packages()
+{
+    # Packages for python cffi
+    PKGLIST="libffi-dev"
+    # kconfig requirements
+    PKGLIST="${PKGLIST} libncurses-dev"
+    # hub-ctrl
+    PKGLIST="${PKGLIST} libusb-dev"
+    # AVR chip installation and building
+    PKGLIST="${PKGLIST} avrdude gcc-avr binutils-avr avr-libc"
+    # ARM chip installation and building
+    PKGLIST="${PKGLIST} bossa-cli libnewlib-arm-none-eabi"
+
+    # Update system package info
+    report_status "Running apt-get update..."
+    sudo apt-get update
+
+    # Install desired packages
+    report_status "Installing packages..."
+    sudo apt-get install --yes ${PKGLIST}
+}
+
+# Step 2: Create python virtual environment
+create_virtualenv()
+{
+    report_status "Updating python virtual environment..."
+
+    # Create virtualenv if it doesn't already exist
+    [ ! -d ${PYTHONDIR} ] && virtualenv ${PYTHONDIR}
+
+    # Install/update dependencies
+    ${PYTHONDIR}/bin/pip install cffi==1.6.0 pyserial==3.2.1 greenlet==0.4.10
+}
+
+# Step 3: Install startup script
+install_script()
+{
+    report_status "Installing system start script..."
+    sudo cp "${SRCDIR}/scripts/klipper-start.sh" /etc/init.d/klipper
+    sudo update-rc.d klipper defaults
+}
+
+# Step 4: Install startup script config
+install_config()
+{
+    DEFAULTS_FILE=/etc/default/klipper
+    [ -f $DEFAULTS_FILE ] && return
+
+    report_status "Installing system start configuration..."
+    sudo /bin/sh -c "cat > $DEFAULTS_FILE" <<EOF
+# Configuration for /etc/init.d/klipper
+
+KLIPPY_USER=$USER
+
+KLIPPY_EXEC=${PYTHONDIR}/bin/python
+
+KLIPPY_ARGS="${SRCDIR}/klippy/klippy.py ${HOME}/printer.cfg -l /tmp/klippy.log"
+
+EOF
+}
+
+# Step 5: Start host software
+start_software()
+{
+    report_status "Launching Klipper host software..."
+    sudo /etc/init.d/klipper restart
+}
+
+# Helper functions
+report_status()
+{
+    echo -e "\n\n###### $1"
+}
+
+verify_ready()
+{
+    if [ "$EUID" -eq 0 ]; then
+        echo "This script must not run as root"
+        exit -1
+    fi
+}
+
+# Force script to exit if an error occurs
+set -e
+
+# Find SRCDIR from the pathname of this script
+SRCDIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )"/.. && pwd )"
+
+# Run installation steps defined above
+verify_ready
+install_packages
+create_virtualenv
+install_script
+install_config
+start_software

scripts/klipper-start.sh

@@ -0,0 +1,54 @@
+#!/bin/sh
+# System startup script for Klipper 3d-printer host code
+
+### BEGIN INIT INFO
+# Provides:          klipper
+# Required-Start:    $local_fs
+# Required-Stop:
+# Default-Start:     2 3 4 5
+# Default-Stop:      0 1 6
+# Short-Description: Klipper daemon
+# Description:       Starts the Klipper daemon.
+### END INIT INFO
+
+PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
+DESC="klipper daemon"
+NAME="klipper"
+DEFAULTS_FILE=/etc/default/klipper
+PIDFILE=/var/run/klipper.pid
+
+. /lib/lsb/init-functions
+
+# Read defaults file
+[ -r $DEFAULTS_FILE ] && . $DEFAULTS_FILE
+
+case "$1" in
+start)  log_daemon_msg "Starting klipper" $NAME
+        start-stop-daemon --start --quiet --exec $KLIPPY_EXEC \
+                          --background --pidfile $PIDFILE --make-pidfile \
+                          --chuid $KLIPPY_USER --user $KLIPPY_USER \
+                          -- $KLIPPY_ARGS
+        log_end_msg $?
+        ;;
+stop)   log_daemon_msg "Stopping klipper" $NAME
+        killproc -p $PIDFILE $KLIPPY_EXEC
+        RETVAL=$?
+        [ $RETVAL -eq 0 ] && [ -e "$PIDFILE" ] && rm -f $PIDFILE
+        log_end_msg $RETVAL
+        ;;
+restart) log_daemon_msg "Restarting klipper" $NAME
+        $0 stop
+        $0 start
+        ;;
+reload|force-reload)
+        log_daemon_msg "Reloading configuration not supported" $NAME
+        log_end_msg 1
+        ;;
+status)
+        status_of_proc -p $PIDFILE $KLIPPY_EXEC $NAME && exit 0 || exit $?
+        ;;
+*)      log_action_msg "Usage: /etc/init.d/klipper {start|stop|status|restart|reload|force-reload}"
+        exit 2
+        ;;
+esac
+exit 0

src/adccmds.c

@@ -4,7 +4,7 @@
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
-#include "basecmd.h" // alloc_oid
+#include "basecmd.h" // oid_alloc
 #include "board/gpio.h" // struct gpio_adc
 #include "board/irq.h" // irq_disable
 #include "command.h" // DECL_COMMAND
@@ -50,7 +50,7 @@ analog_in_event(struct timer *timer)
 void
 command_config_analog_in(uint32_t *args)
 {
-    struct analog_in *a = alloc_oid(
+    struct analog_in *a = oid_alloc(
         args[0], command_config_analog_in, sizeof(*a));
     a->timer.func = analog_in_event;
     a->pin = gpio_adc_setup(args[1]);
@@ -61,7 +61,7 @@ DECL_COMMAND(command_config_analog_in, "config_analog_in oid=%c pin=%u");
 void
 command_query_analog_in(uint32_t *args)
 {
-    struct analog_in *a = lookup_oid(args[0], command_config_analog_in);
+    struct analog_in *a = oid_lookup(args[0], command_config_analog_in);
     sched_del_timer(&a->timer);
     gpio_adc_cancel_sample(a->pin);
     a->next_begin_time = args[1];
@@ -74,7 +74,7 @@ command_query_analog_in(uint32_t *args)
     a->max_value = args[6];
     if (! a->sample_count)
         return;
-    sched_timer(&a->timer);
+    sched_add_timer(&a->timer);
 }
 DECL_COMMAND(command_query_analog_in,
              "query_analog_in oid=%c clock=%u sample_ticks=%u sample_count=%c"

src/avr/Makefile

@@ -5,8 +5,7 @@ CROSS_PREFIX=avr-
 
 dirs-y += src/avr lib/pjrc_usb_serial
 
-CFLAGS-y += -Os -mmcu=$(CONFIG_MCU) -DF_CPU=$(CONFIG_CLOCK_FREQ)
-LDFLAGS-y += -Wl,--relax
+CFLAGS-y += -mmcu=$(CONFIG_MCU)
 
 # Add avr source files
 src-y += avr/main.c avr/timer.c avr/gpio.c avr/misc.c
@@ -14,9 +13,16 @@ src-$(CONFIG_AVR_WATCHDOG) += avr/watchdog.c
 src-$(CONFIG_AVR_USBSERIAL) += avr/usbserial.c ../lib/pjrc_usb_serial/usb_serial.c
 src-$(CONFIG_AVR_SERIAL) += avr/serial.c
 
+# Suppress broken "misspelled signal handler" warnings on gcc 4.8.1
+CFLAGS_klipper.o := $(if $(filter 4.8.1, $(shell $(CC) -dumpversion)), -w)
+
 # Build the additional hex output file
 target-y += $(OUT)klipper.elf.hex
 
 $(OUT)klipper.elf.hex: $(OUT)klipper.elf
 	@echo "  Creating hex file $@"
 	$(Q)$(OBJCOPY) -j .text -j .data -O ihex $< $@
+
+flash: $(OUT)klipper.elf.hex
+	@echo "  Flashing $(FLASH_DEVICE) via avrdude"
+	$(Q)avrdude -p$(CONFIG_MCU) -cwiring -P"$(FLASH_DEVICE)" -D -U"flash:w:$(OUT)klipper.elf.hex:i"

src/avr/gpio.c

@@ -1,6 +1,6 @@
 // GPIO functions on AVR.
 //
-// Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
@@ -14,7 +14,7 @@
 
 
 /****************************************************************
- * AVR chip definitions
+ * General Purpose Input Output (GPIO) pins
  ****************************************************************/
 
 #define GPIO(PORT, NUM) (((PORT)-'A') * 8 + (NUM))
@@ -44,6 +44,67 @@ struct gpio_digital_regs {
 #define GPIO2REGS(pin)                                                  \
     ((struct gpio_digital_regs*)READP(digital_regs[GPIO2PORT(pin)]))
 
+struct gpio_out
+gpio_out_setup(uint8_t pin, uint8_t val)
+{
+    if (GPIO2PORT(pin) >= ARRAY_SIZE(digital_regs))
+        goto fail;
+    struct gpio_digital_regs *regs = GPIO2REGS(pin);
+    if (! regs)
+        goto fail;
+    uint8_t bit = GPIO2BIT(pin);
+    irqstatus_t flag = irq_save();
+    regs->out = val ? (regs->out | bit) : (regs->out & ~bit);
+    regs->mode |= bit;
+    irq_restore(flag);
+    return (struct gpio_out){ .regs=regs, .bit=bit };
+fail:
+    shutdown("Not an output pin");
+}
+
+void
+gpio_out_toggle(struct gpio_out g)
+{
+    g.regs->in = g.bit;
+}
+
+void
+gpio_out_write(struct gpio_out g, uint8_t val)
+{
+    irqstatus_t flag = irq_save();
+    g.regs->out = val ? (g.regs->out | g.bit) : (g.regs->out & ~g.bit);
+    irq_restore(flag);
+}
+
+struct gpio_in
+gpio_in_setup(uint8_t pin, int8_t pull_up)
+{
+    if (GPIO2PORT(pin) >= ARRAY_SIZE(digital_regs))
+        goto fail;
+    struct gpio_digital_regs *regs = GPIO2REGS(pin);
+    if (! regs)
+        goto fail;
+    uint8_t bit = GPIO2BIT(pin);
+    irqstatus_t flag = irq_save();
+    regs->out = pull_up > 0 ? (regs->out | bit) : (regs->out & ~bit);
+    regs->mode &= ~bit;
+    irq_restore(flag);
+    return (struct gpio_in){ .regs=regs, .bit=bit };
+fail:
+    shutdown("Not an input pin");
+}
+
+uint8_t
+gpio_in_read(struct gpio_in g)
+{
+    return !!(g.regs->in & g.bit);
+}
+
+
+/****************************************************************
+ * Hardware Pulse Width Modulation (PWM) pins
+ ****************************************************************/
+
 struct gpio_pwm_info {
     volatile void *ocr;
     volatile uint8_t *rega, *regb;
@@ -101,116 +162,21 @@ static const uint8_t pwm_pins[ARRAY_SIZE(pwm_regs)] PROGMEM = {
 #endif
 };
 
-static const uint8_t adc_pins[] PROGMEM = {
-#if CONFIG_MACH_atmega168
-    GPIO('C', 0), GPIO('C', 1), GPIO('C', 2), GPIO('C', 3),
-    GPIO('C', 4), GPIO('C', 5), GPIO('E', 0), GPIO('E', 1),
-#elif CONFIG_MACH_atmega644p
-    GPIO('A', 0), GPIO('A', 1), GPIO('A', 2), GPIO('A', 3),
-    GPIO('A', 4), GPIO('A', 5), GPIO('A', 6), GPIO('A', 7),
-#elif CONFIG_MACH_at90usb1286
-    GPIO('F', 0), GPIO('F', 1), GPIO('F', 2), GPIO('F', 3),
-    GPIO('F', 4), GPIO('F', 5), GPIO('F', 6), GPIO('F', 7),
-#elif CONFIG_MACH_atmega1280 || CONFIG_MACH_atmega2560
-    GPIO('F', 0), GPIO('F', 1), GPIO('F', 2), GPIO('F', 3),
-    GPIO('F', 4), GPIO('F', 5), GPIO('F', 6), GPIO('F', 7),
-    GPIO('K', 0), GPIO('K', 1), GPIO('K', 2), GPIO('K', 3),
-    GPIO('K', 4), GPIO('K', 5), GPIO('K', 6), GPIO('K', 7),
-#endif
-};
-
-#if CONFIG_MACH_atmega168
-static const uint8_t SS = GPIO('B', 2), SCK = GPIO('B', 5), MOSI = GPIO('B', 3);
-#elif CONFIG_MACH_atmega644p
-static const uint8_t SS = GPIO('B', 4), SCK = GPIO('B', 7), MOSI = GPIO('B', 5);
-#elif CONFIG_MACH_at90usb1286 || CONFIG_MACH_atmega1280 || CONFIG_MACH_atmega2560
-static const uint8_t SS = GPIO('B', 0), SCK = GPIO('B', 1), MOSI = GPIO('B', 2);
-#endif
-
-static const uint8_t ADMUX_DEFAULT = 0x40;
-
-
-/****************************************************************
- * gpio functions
- ****************************************************************/
-
-struct gpio_out
-gpio_out_setup(uint8_t pin, uint8_t val)
-{
-    if (GPIO2PORT(pin) >= ARRAY_SIZE(digital_regs))
-        goto fail;
-    struct gpio_digital_regs *regs = GPIO2REGS(pin);
-    if (! regs)
-        goto fail;
-    uint8_t bit = GPIO2BIT(pin);
-    irqstatus_t flag = irq_save();
-    regs->out = val ? (regs->out | bit) : (regs->out & ~bit);
-    regs->mode |= bit;
-    irq_restore(flag);
-    return (struct gpio_out){ .regs=regs, .bit=bit };
-fail:
-    shutdown("Not an output pin");
-}
-
-void gpio_out_toggle(struct gpio_out g)
-{
-    g.regs->in = g.bit;
-}
-
-void
-gpio_out_write(struct gpio_out g, uint8_t val)
-{
-    irqstatus_t flag = irq_save();
-    g.regs->out = val ? (g.regs->out | g.bit) : (g.regs->out & ~g.bit);
-    irq_restore(flag);
-}
-
-struct gpio_in
-gpio_in_setup(uint8_t pin, int8_t pull_up)
-{
-    if (GPIO2PORT(pin) >= ARRAY_SIZE(digital_regs))
-        goto fail;
-    struct gpio_digital_regs *regs = GPIO2REGS(pin);
-    if (! regs)
-        goto fail;
-    uint8_t bit = GPIO2BIT(pin);
-    irqstatus_t flag = irq_save();
-    regs->out = pull_up > 0 ? (regs->out | bit) : (regs->out & ~bit);
-    regs->mode &= ~bit;
-    irq_restore(flag);
-    return (struct gpio_in){ .regs=regs, .bit=bit };
-fail:
-    shutdown("Not an input pin");
-}
-
-uint8_t
-gpio_in_read(struct gpio_in g)
-{
-    return !!(g.regs->in & g.bit);
-}
-
-
-void
-gpio_pwm_write(struct gpio_pwm g, uint8_t val)
-{
-    if (g.size8) {
-        *(volatile uint8_t*)g.reg = val;
-    } else {
-        irqstatus_t flag = irq_save();
-        *(volatile uint16_t*)g.reg = val;
-        irq_restore(flag);
-    }
-}
-
 struct gpio_pwm
 gpio_pwm_setup(uint8_t pin, uint32_t cycle_time, uint8_t val)
 {
+    // Find pin in pwm_pins table
     uint8_t chan;
-    for (chan=0; chan<ARRAY_SIZE(pwm_regs); chan++) {
-        if (READP(pwm_pins[chan]) != pin)
-            continue;
+    for (chan=0; ; chan++) {
+        if (chan >= ARRAY_SIZE(pwm_pins))
+            shutdown("Not a valid PWM pin");
+        if (READP(pwm_pins[chan]) == pin)
+            break;
+    }
+
+    // Map cycle_time to pwm clock divisor
     const struct gpio_pwm_info *p = &pwm_regs[chan];
-        irqstatus_t flags = READP(p->flags), cs;
+    uint8_t flags = READP(p->flags), cs;
     if (flags & GP_AFMT) {
         switch (cycle_time) {
         case 0        ...    8*510L - 1: cs = 1; break;
@@ -232,12 +198,12 @@ gpio_pwm_setup(uint8_t pin, uint32_t cycle_time, uint8_t val)
     }
     volatile uint8_t *rega = READP(p->rega), *regb = READP(p->regb);
     uint8_t en_bit = READP(p->en_bit);
-        struct gpio_digital_regs *regs = GPIO2REGS(pin);
-        uint8_t bit = GPIO2BIT(pin);
+    struct gpio_digital_regs *gpio_regs = GPIO2REGS(pin);
+    uint8_t gpio_bit = GPIO2BIT(pin);
     struct gpio_pwm g = (struct gpio_pwm) {
         (void*)READP(p->ocr), flags & GP_8BIT };
     if (rega == &TCCR1A)
-            shutdown("Can not user timer1 for PWM; timer1 is used for timers");
+        shutdown("Can not use timer1 for PWM; timer1 is used for timers");
 
     // Setup PWM timer
     irqstatus_t flag = irq_save();
@@ -249,24 +215,62 @@ gpio_pwm_setup(uint8_t pin, uint32_t cycle_time, uint8_t val)
     // Set default value and enable output
     gpio_pwm_write(g, val);
     *rega |= (1<<WGM00) | en_bit;
-        regs->mode |= bit;
+    gpio_regs->mode |= gpio_bit;
     irq_restore(flag);
 
     return g;
 }
-    shutdown("Not a valid PWM pin");
+
+void
+gpio_pwm_write(struct gpio_pwm g, uint8_t val)
+{
+    if (g.size8) {
+        *(volatile uint8_t*)g.reg = val;
+    } else {
+        irqstatus_t flag = irq_save();
+        *(volatile uint16_t*)g.reg = val;
+        irq_restore(flag);
+    }
 }
 
 
+/****************************************************************
+ * Analog to Digital Converter (ADC) pins
+ ****************************************************************/
+
+static const uint8_t adc_pins[] PROGMEM = {
+#if CONFIG_MACH_atmega168
+    GPIO('C', 0), GPIO('C', 1), GPIO('C', 2), GPIO('C', 3),
+    GPIO('C', 4), GPIO('C', 5), GPIO('E', 0), GPIO('E', 1),
+#elif CONFIG_MACH_atmega644p
+    GPIO('A', 0), GPIO('A', 1), GPIO('A', 2), GPIO('A', 3),
+    GPIO('A', 4), GPIO('A', 5), GPIO('A', 6), GPIO('A', 7),
+#elif CONFIG_MACH_at90usb1286
+    GPIO('F', 0), GPIO('F', 1), GPIO('F', 2), GPIO('F', 3),
+    GPIO('F', 4), GPIO('F', 5), GPIO('F', 6), GPIO('F', 7),
+#elif CONFIG_MACH_atmega1280 || CONFIG_MACH_atmega2560
+    GPIO('F', 0), GPIO('F', 1), GPIO('F', 2), GPIO('F', 3),
+    GPIO('F', 4), GPIO('F', 5), GPIO('F', 6), GPIO('F', 7),
+    GPIO('K', 0), GPIO('K', 1), GPIO('K', 2), GPIO('K', 3),
+    GPIO('K', 4), GPIO('K', 5), GPIO('K', 6), GPIO('K', 7),
+#endif
+};
+
+static const uint8_t ADMUX_DEFAULT = 0x40;
+
 DECL_CONSTANT(ADC_MAX, 1024);
 
 struct gpio_adc
 gpio_adc_setup(uint8_t pin)
 {
+    // Find pin in adc_pins table
     uint8_t chan;
-    for (chan=0; chan<ARRAY_SIZE(adc_pins); chan++) {
-        if (READP(adc_pins[chan]) != pin)
-            continue;
+    for (chan=0; ; chan++) {
+        if (chan >= ARRAY_SIZE(adc_pins))
+            shutdown("Not a valid ADC pin");
+        if (READP(adc_pins[chan]) == pin)
+            break;
+    }
 
     // Enable ADC
     ADCSRA |= (1<<ADPS0)|(1<<ADPS1)|(1<<ADPS2)|(1<<ADEN);
@@ -281,8 +285,6 @@ gpio_adc_setup(uint8_t pin)
 
     return (struct gpio_adc){ chan };
 }
-    shutdown("Not a valid ADC pin");
-}
 
 enum { ADC_DUMMY=0xff };
 static uint8_t last_analog_read = ADC_DUMMY;
@@ -335,6 +337,18 @@ gpio_adc_cancel_sample(struct gpio_adc g)
 }
 
 
+/****************************************************************
+ * Serial Peripheral Interface (SPI) hardware
+ ****************************************************************/
+
+#if CONFIG_MACH_atmega168
+static const uint8_t SS = GPIO('B', 2), SCK = GPIO('B', 5), MOSI = GPIO('B', 3);
+#elif CONFIG_MACH_atmega644p
+static const uint8_t SS = GPIO('B', 4), SCK = GPIO('B', 7), MOSI = GPIO('B', 5);
+#elif CONFIG_MACH_at90usb1286 || CONFIG_MACH_atmega1280 || CONFIG_MACH_atmega2560
+static const uint8_t SS = GPIO('B', 0), SCK = GPIO('B', 1), MOSI = GPIO('B', 2);
+#endif
+
 void
 spi_config(void)
 {

src/avr/main.c

@@ -4,9 +4,13 @@
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
+#include "autoconf.h" // CONFIG_MCU
+#include "command.h" // DECL_CONSTANT
 #include "irq.h" // irq_enable
 #include "sched.h" // sched_main
 
+DECL_CONSTANT(MCU, CONFIG_MCU);
+
 // Main entry point for avr code.
 int
 main(void)

src/avr/serial.c

@@ -30,10 +30,12 @@ serial_init(void)
 {
     if (CONFIG_SERIAL_BAUD_U2X) {
         UCSR0A = 1<<U2X0;
-        UBRR0 = DIV_ROUND_CLOSEST(F_CPU, 8UL * CONFIG_SERIAL_BAUD) - 1UL;
+        UBRR0 = DIV_ROUND_CLOSEST(
+            CONFIG_CLOCK_FREQ, 8UL * CONFIG_SERIAL_BAUD) - 1UL;
     } else {
         UCSR0A = 0;
-        UBRR0 = DIV_ROUND_CLOSEST(F_CPU, 16UL * CONFIG_SERIAL_BAUD) - 1UL;
+        UBRR0 = DIV_ROUND_CLOSEST(
+            CONFIG_CLOCK_FREQ, 16UL * CONFIG_SERIAL_BAUD) - 1UL;
     }
 
     UCSR0C = (1<<UCSZ01) | (1<<UCSZ00);
@@ -115,7 +117,7 @@ char *
 console_get_output(uint8_t len)
 {
     uint8_t tpos = readb(&transmit_pos), tmax = readb(&transmit_max);
-    if (tpos == tmax) {
+    if (tpos >= tmax) {
         tpos = tmax = 0;
         writeb(&transmit_max, 0);
         writeb(&transmit_pos, 0);
@@ -126,12 +128,10 @@ console_get_output(uint8_t len)
         return NULL;
     // Disable TX irq and move buffer
     writeb(&transmit_max, 0);
-    barrier();
     tpos = readb(&transmit_pos);
     tmax -= tpos;
     memmove(&transmit_buf[0], &transmit_buf[tpos], tmax);
     writeb(&transmit_pos, 0);
-    barrier();
     writeb(&transmit_max, tmax);
     enable_tx_irq();
     return &transmit_buf[tmax];

src/avr/timer.c

@@ -16,14 +16,38 @@
  * Low level timer code
  ****************************************************************/
 
-DECL_CONSTANT(CLOCK_FREQ, F_CPU);
-DECL_CONSTANT(MCU, CONFIG_MCU);
+DECL_CONSTANT(CLOCK_FREQ, CONFIG_CLOCK_FREQ);
 
 // Return the number of clock ticks for a given number of microseconds
 uint32_t
 timer_from_us(uint32_t us)
 {
-    return us * (F_CPU / 1000000);
+    return us * (CONFIG_CLOCK_FREQ / 1000000);
+}
+
+union u32_u {
+    struct { uint8_t b0, b1, b2, b3; };
+    struct { uint16_t lo, hi; };
+    uint32_t val;
+};
+
+// Return true if time1 is before time2.  Always use this function to
+// compare times as regular C comparisons can fail if the counter
+// rolls over.
+uint8_t __always_inline
+timer_is_before(uint32_t time1, uint32_t time2)
+{
+    // This asm is equivalent to:
+    //     return (int32_t)(time1 - time2) < 0;
+    // But gcc doesn't do a good job with the above, so it's hand coded.
+    union u32_u utime1 = { .val = time1 };
+    uint8_t f = utime1.b3;
+    asm("    cp  %A1, %A2\n"
+        "    cpc %B1, %B2\n"
+        "    cpc %C1, %C2\n"
+        "    sbc %0,  %D2"
+        : "+r"(f) : "r"(time1), "r"(time2));
+    return (int8_t)f < 0;
 }
 
 static inline uint16_t
@@ -38,13 +62,6 @@ timer_set(uint16_t next)
     OCR1A = next;
 }
 
-static inline void
-timer_set_clear(uint16_t next)
-{
-    OCR1A = next;
-    TIFR1 = 1<<OCF1A;
-}
-
 static inline void
 timer_repeat_set(uint16_t next)
 {
@@ -53,10 +70,16 @@ timer_repeat_set(uint16_t next)
     TIFR1 = 1<<OCF1B;
 }
 
-ISR(TIMER1_COMPA_vect)
+// Reset the timer - clear settings and dispatch next timer immediately
+static void
+timer_reset(void)
 {
-    sched_timer_kick();
+    uint16_t now = timer_get();
+    timer_set(now + 50);
+    TIFR1 = 1<<OCF1A;
+    timer_repeat_set(now + 50);
 }
+DECL_SHUTDOWN(timer_reset);
 
 static void
 timer_init(void)
@@ -73,8 +96,13 @@ timer_init(void)
     TCCR1A = 0;
     // Normal Mode
     TCCR1B = 1<<CS10;
+    // Setup for first irq
+    irqstatus_t flag = irq_save();
+    timer_reset();
+    TIFR1 = 1<<TOV1;
     // enable interrupt
     TIMSK1 = 1<<OCIE1A;
+    irq_restore(flag);
 }
 DECL_INIT(timer_init);
 
@@ -83,20 +111,19 @@ DECL_INIT(timer_init);
  * 32bit timer wrappers
  ****************************************************************/
 
-static uint32_t timer_last;
+static uint16_t timer_high;
 
-// Return the 32bit current time given the 16bit current time.
-static __always_inline uint32_t
-calc_time(uint32_t last, uint16_t cur)
+// Return the current time (in absolute clock ticks).
+uint32_t
+timer_read_time(void)
 {
-    union u32_u16_u {
-        struct { uint16_t lo, hi; };
-        uint32_t val;
-    } calc;
-    calc.val = last;
-    if (cur < calc.lo)
+    irqstatus_t flag = irq_save();
+    union u32_u calc;
+    calc.val = timer_get();
+    calc.hi = timer_high;
+    if (TIFR1 & (1<<TOV1) && calc.lo < 0x8000)
         calc.hi++;
-    calc.lo = cur;
+    irq_restore(flag);
     return calc.val;
 }
 
@@ -104,39 +131,11 @@ calc_time(uint32_t last, uint16_t cur)
 void
 timer_periodic(void)
 {
-    timer_last = calc_time(timer_last, timer_get());
+    if (TIFR1 & (1<<TOV1)) {
+        // Hardware timer has overflowed - update overflow counter
+        TIFR1 = 1<<TOV1;
+        timer_high++;
     }
-
-// Return the current time (in absolute clock ticks).
-uint32_t
-timer_read_time(void)
-{
-    irqstatus_t flag = irq_save();
-    uint16_t cur = timer_get();
-    uint32_t last = timer_last;
-    irq_restore(flag);
-    return calc_time(last, cur);
-}
-
-#define TIMER_MIN_TICKS 100
-
-// Set the next timer wake time (in absolute clock ticks).  Caller
-// must disable irqs.  The caller should not schedule a time more than
-// a few milliseconds in the future.
-uint8_t
-timer_set_next(uint32_t next)
-{
-    uint16_t cur = timer_get();
-    if ((int16_t)(OCR1A - cur) < 0 && !(TIFR1 & (1<<OCF1A)))
-        // Already processing timer irqs
-        try_shutdown("timer_set_next called during timer dispatch");
-    uint32_t mintime = calc_time(timer_last, cur + TIMER_MIN_TICKS);
-    if (sched_is_before(mintime, next)) {
-        timer_set_clear(next);
-        return 0;
-    }
-    timer_set_clear(mintime);
-    return 1;
 }
 
 #define TIMER_IDLE_REPEAT_TICKS 8000
@@ -145,45 +144,51 @@ timer_set_next(uint32_t next)
 #define TIMER_MIN_TRY_TICKS 60 // 40 ticks to exit irq; 20 ticks of progress
 #define TIMER_DEFER_REPEAT_TICKS 200
 
-// Similar to timer_set_next(), but wait for the given time if it is
-// in the near future.
-uint8_t
-timer_try_set_next(uint32_t target)
+// Hardware timer IRQ handler - dispatch software timers
+ISR(TIMER1_COMPA_vect)
 {
-    uint16_t next = target, now = timer_get();
-    int16_t diff = next - now;
-    if (diff > TIMER_MIN_TRY_TICKS)
-        // Schedule next timer normally.
+    uint16_t next;
+    for (;;) {
+        // Run the next software timer
+        next = sched_timer_dispatch();
+
+        int16_t diff = timer_get() - next;
+        if (likely(diff >= 0)) {
+            // Another timer is pending - briefly allow irqs to fire
+            irq_enable();
+            if (unlikely(TIFR1 & (1<<OCF1B)))
+                // Too many repeat timers - must exit irq handler
+                goto force_defer;
+            irq_disable();
+            continue;
+        }
+
+        if (likely(diff <= -TIMER_MIN_TRY_TICKS))
+            // Schedule next timer normally
             goto done;
 
-    // Next timer is in the past or near future - can't reschedule to it
-    if (!(TIFR1 & (1<<OCF1B))) {
-        // Can run more timers from this irq; briefly allow irqs
+        // Next timer in very near future - wait for it to be ready
+        do {
             irq_enable();
-        asm("nop");
-        irq_disable();
-
-        while (diff >= 0) {
-            // Next timer is in the near future - wait for time to occur
-            now = timer_get();
-            irq_enable();
-            diff = next - now;
+            if (unlikely(TIFR1 & (1<<OCF1B)))
+                goto force_defer;
             irq_disable();
+            diff = timer_get() - next;
+        } while (diff < 0);
     }
-        return 0;
-    }
-    if (diff < (int16_t)(-timer_from_us(1000)))
-        goto fail;
 
+force_defer:
     // Too many repeat timers - force a pause so tasks aren't starved
+    irq_disable();
+    uint16_t now = timer_get();
+    if ((int16_t)(next - now) < (int16_t)(-timer_from_us(1000)))
+        shutdown("Rescheduled timer in the past");
     timer_repeat_set(now + TIMER_REPEAT_TICKS);
     next = now + TIMER_DEFER_REPEAT_TICKS;
 
 done:
     timer_set(next);
-    return 1;
-fail:
-    shutdown("Rescheduled timer in the past");
+    return;
 }
 
 // Periodic background task that temporarily boosts priority of

src/avr/watchdog.c

@@ -7,6 +7,7 @@
 #include <avr/interrupt.h> // WDT_vect
 #include <avr/wdt.h> // wdt_enable
 #include "command.h" // shutdown
+#include "irq.h" // irq_disable
 #include "sched.h" // DECL_TASK
 
 static uint8_t watchdog_shutdown;
@@ -22,7 +23,7 @@ watchdog_reset(void)
 {
     wdt_reset();
     if (watchdog_shutdown) {
-        WDTCSR |= 1<<WDIE;
+        WDTCSR = 1<<WDIE;
         watchdog_shutdown = 0;
     }
 }
@@ -33,6 +34,25 @@ watchdog_init(void)
 {
     // 0.5s timeout, interrupt and system reset
     wdt_enable(WDTO_500MS);
-    WDTCSR |= 1<<WDIE;
+    WDTCSR = 1<<WDIE;
 }
 DECL_INIT(watchdog_init);
+
+// Very early reset of the watchdog
+void __attribute__((naked)) __visible __section(".init3")
+watchdog_early_init(void)
+{
+    MCUSR = 0;
+    wdt_disable();
+}
+
+// Support reset on AVR via the watchdog timer
+void
+command_reset(uint32_t *args)
+{
+    irq_disable();
+    wdt_enable(WDTO_15MS);
+    for (;;)
+        ;
+}
+DECL_COMMAND_FLAGS(command_reset, HF_IN_SHUTDOWN, "reset");

src/basecmd.c

@@ -5,8 +5,8 @@
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
 #include <stdlib.h> // malloc
-#include <string.h> // memcpy
-#include "basecmd.h" // lookup_oid
+#include <string.h> // memset
+#include "basecmd.h" // oid_lookup
 #include "board/irq.h" // irq_save
 #include "board/misc.h" // alloc_maxsize
 #include "command.h" // DECL_COMMAND
@@ -17,26 +17,53 @@
  * Move queue
  ****************************************************************/
 
-static struct move *move_list, *move_free_list;
-static uint16_t move_count;
+struct move_freed {
+    struct move_freed *next;
+};
 
-void
-move_free(struct move *m)
+static struct move_freed *move_free_list;
+static void *move_list;
+static uint16_t move_count;
+static uint8_t move_item_size;
+
+// Is the config and move queue finalized?
+static int
+is_finalized(void)
 {
-    m->next = move_free_list;
-    move_free_list = m;
+    return !!move_count;
 }
 
-struct move *
+// Free previously allocated storage from move_alloc(). Caller must
+// disable irqs.
+void
+move_free(void *m)
+{
+    struct move_freed *mf = m;
+    mf->next = move_free_list;
+    move_free_list = mf;
+}
+
+// Allocate runtime storage
+void *
 move_alloc(void)
 {
     irqstatus_t flag = irq_save();
-    struct move *m = move_free_list;
-    if (!m)
+    struct move_freed *mf = move_free_list;
+    if (!mf)
         shutdown("Move queue empty");
-    move_free_list = m->next;
+    move_free_list = mf->next;
     irq_restore(flag);
-    return m;
+    return mf;
+}
+
+// Request minimum size of runtime allocations returned by move_alloc()
+void
+move_request_size(int size)
+{
+    if (size > UINT8_MAX || is_finalized())
+        shutdown("Invalid move request size");
+    if (size > move_item_size)
+        move_item_size = size;
 }
 
 static void
@@ -46,13 +73,28 @@ move_reset(void)
         return;
     // Add everything in move_list to the free list.
     uint32_t i;
-    for (i=0; i<move_count-1; i++)
-        move_list[i].next = &move_list[i+1];
-    move_list[move_count-1].next = NULL;
-    move_free_list = &move_list[0];
+    for (i=0; i<move_count-1; i++) {
+        struct move_freed *mf = move_list + i*move_item_size;
+        mf->next = move_list + (i + 1)*move_item_size;
+    }
+    struct move_freed *mf = move_list + (move_count - 1)*move_item_size;
+    mf->next = NULL;
+    move_free_list = move_list;
 }
 DECL_SHUTDOWN(move_reset);
 
+static void
+move_finalize(void)
+{
+    move_request_size(sizeof(*move_free_list));
+    uint16_t count = alloc_maxsize(move_item_size*1024) / move_item_size;
+    move_list = malloc(count * move_item_size);
+    if (!count || !move_list)
+        shutdown("move queue malloc failed");
+    move_count = count;
+    move_reset();
+}
+
 
 /****************************************************************
  * Generic object ids (oid)
@@ -63,45 +105,43 @@ struct oid_s {
 };
 
 static struct oid_s *oids;
-static uint8_t num_oid;
-static uint32_t config_crc;
-static uint8_t config_finalized;
+static uint8_t oid_count;
 
 void *
-lookup_oid(uint8_t oid, void *type)
+oid_lookup(uint8_t oid, void *type)
 {
-    if (oid >= num_oid || type != oids[oid].type)
+    if (oid >= oid_count || type != oids[oid].type)
         shutdown("Invalid oid type");
     return oids[oid].data;
 }
 
 static void
-assign_oid(uint8_t oid, void *type, void *data)
+oid_assign(uint8_t oid, void *type, void *data)
 {
-    if (oid >= num_oid || oids[oid].type || config_finalized)
+    if (oid >= oid_count || oids[oid].type || is_finalized())
         shutdown("Can't assign oid");
     oids[oid].type = type;
     oids[oid].data = data;
 }
 
 void *
-alloc_oid(uint8_t oid, void *type, uint16_t size)
+oid_alloc(uint8_t oid, void *type, uint16_t size)
 {
     void *data = malloc(size);
     if (!data)
         shutdown("malloc failed");
     memset(data, 0, size);
-    assign_oid(oid, type, data);
+    oid_assign(oid, type, data);
     return data;
 }
 
 void *
-next_oid(uint8_t *i, void *type)
+oid_next(uint8_t *i, void *type)
 {
     uint8_t oid = *i;
     for (;;) {
         oid++;
-        if (oid >= num_oid)
+        if (oid >= oid_count)
             return NULL;
         if (oids[oid].type == type) {
             *i = oid;
@@ -120,31 +160,32 @@ command_allocate_oids(uint32_t *args)
     if (!oids)
         shutdown("malloc failed");
     memset(oids, 0, sizeof(oids[0]) * count);
-    num_oid = count;
+    oid_count = count;
 }
 DECL_COMMAND(command_allocate_oids, "allocate_oids count=%c");
 
+
+/****************************************************************
+ * Config CRC
+ ****************************************************************/
+
+static uint32_t config_crc;
+
 void
 command_get_config(uint32_t *args)
 {
     sendf("config is_config=%c crc=%u move_count=%hu"
-          , config_finalized, config_crc, move_count);
+          , is_finalized(), config_crc, move_count);
 }
 DECL_COMMAND_FLAGS(command_get_config, HF_IN_SHUTDOWN, "get_config");
 
 void
 command_finalize_config(uint32_t *args)
 {
-    if (!oids || config_finalized)
+    if (!oids || is_finalized())
         shutdown("Can't finalize");
-    uint16_t count = alloc_maxsize(sizeof(*move_list)*1024) / sizeof(*move_list);
-    move_list = malloc(count * sizeof(*move_list));
-    if (!count || !move_list)
-        shutdown("malloc failed");
-    move_count = count;
-    move_reset();
+    move_finalize();
     config_crc = args[0];
-    config_finalized = 1;
     command_get_config(NULL);
 }
 DECL_COMMAND(command_finalize_config, "finalize_config crc=%u");
@@ -168,7 +209,7 @@ command_start_group(uint32_t *args)
     sched_del_timer(&group_timer);
     group_timer.func = group_end_event;
     group_timer.waketime = args[0];
-    sched_timer(&group_timer);
+    sched_add_timer(&group_timer);
 }
 DECL_COMMAND(command_start_group, "start_group clock=%u");
 
@@ -187,28 +228,51 @@ DECL_COMMAND(command_end_group, "end_group");
 void
 command_get_status(uint32_t *args)
 {
-    sendf("status clock=%u status=%c", sched_read_time(), sched_is_shutdown());
+    sendf("status clock=%u status=%c", timer_read_time(), sched_is_shutdown());
 }
 DECL_COMMAND_FLAGS(command_get_status, HF_IN_SHUTDOWN, "get_status");
 
+static uint32_t stats_send_time, stats_send_time_high;
+
+void
+command_get_uptime(uint32_t *args)
+{
+    uint32_t cur = timer_read_time();
+    uint32_t high = stats_send_time_high + (cur < stats_send_time);
+    sendf("uptime high=%u clock=%u", high, cur);
+}
+DECL_COMMAND_FLAGS(command_get_uptime, HF_IN_SHUTDOWN, "get_uptime");
+
+#define SUMSQ_BASE 256
+DECL_CONSTANT(STATS_SUMSQ_BASE, SUMSQ_BASE);
+
 static void
 stats_task(void)
 {
     static uint32_t last, count, sumsq;
-    uint32_t cur = sched_read_time();
-    uint32_t diff = (cur - last) >> 8;
+    uint32_t cur = timer_read_time();
+    uint32_t diff = cur - last;
     last = cur;
     count++;
-    uint32_t nextsumsq = sumsq + diff*diff;
+    // Calculate sum of diff^2 - be careful of integer overflow
+    uint32_t nextsumsq;
+    if (diff <= 0xffff) {
+        nextsumsq = sumsq + DIV_ROUND_UP(diff * diff, SUMSQ_BASE);
+    } else if (diff <= 0xfffff) {
+        nextsumsq = sumsq + DIV_ROUND_UP(diff, SUMSQ_BASE) * diff;
+    } else {
+        nextsumsq = 0xffffffff;
+    }
     if (nextsumsq < sumsq)
         nextsumsq = 0xffffffff;
     sumsq = nextsumsq;
 
-    static uint32_t prev;
-    if (sched_is_before(cur, prev + sched_from_us(5000000)))
+    if (timer_is_before(cur, stats_send_time + timer_from_us(5000000)))
         return;
-    sendf("stats count=%u sum=%u sumsq=%u", count, cur - prev, sumsq);
-    prev = cur;
+    sendf("stats count=%u sum=%u sumsq=%u", count, cur - stats_send_time, sumsq);
+    if (cur < stats_send_time)
+        stats_send_time_high++;
+    stats_send_time = cur;
     count = sumsq = 0;
 }
 DECL_TASK(stats_task);
@@ -258,18 +322,26 @@ command_debug_write16(uint32_t *args)
 DECL_COMMAND_FLAGS(command_debug_write16, HF_IN_SHUTDOWN,
                    "debug_write16 addr=%u val=%u");
 
+void
+command_debug_ping(uint32_t *args)
+{
+    uint8_t len = args[0];
+    char *data = (void*)(size_t)args[1];
+    sendf("pong data=%*s", len, data);
+}
+DECL_COMMAND_FLAGS(command_debug_ping, HF_IN_SHUTDOWN, "debug_ping data=%*s");
+
+void
+command_debug_nop(uint32_t *args)
+{
+}
+DECL_COMMAND_FLAGS(command_debug_nop, HF_IN_SHUTDOWN, "debug_nop data=%*s");
+
 
 /****************************************************************
  * Misc commands
  ****************************************************************/
 
-void
-command_reset(uint32_t *args)
-{
-    // XXX - implement reset
-}
-DECL_COMMAND_FLAGS(command_reset, HF_IN_SHUTDOWN, "msg_reset");
-
 void
 command_emergency_stop(uint32_t *args)
 {

src/basecmd.h

@@ -3,21 +3,14 @@
 
 #include <stdint.h> // uint8_t
 
-struct move {
-    uint32_t interval;
-    int16_t add;
-    uint16_t count;
-    struct move *next;
-    uint8_t flags;
-};
-
-void move_free(struct move *m);
-struct move *move_alloc(void);
-void *lookup_oid(uint8_t oid, void *type);
-void *alloc_oid(uint8_t oid, void *type, uint16_t size);
-void *next_oid(uint8_t *i, void *type);
+void move_free(void *m);
+void *move_alloc(void);
+void move_request_size(int size);
+void *oid_lookup(uint8_t oid, void *type);
+void *oid_alloc(uint8_t oid, void *type, uint16_t size);
+void *oid_next(uint8_t *i, void *type);
 
 #define foreach_oid(pos,data,oidtype)                   \
-    for (pos=-1; (data=next_oid(&pos, oidtype)); )
+    for (pos=-1; (data=oid_next(&pos, oidtype)); )
 
 #endif // basecmd.h

src/command.c

@@ -4,12 +4,9 @@
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
-#include <ctype.h> // isspace
 #include <stdarg.h> // va_start
-#include <stdio.h> // vsnprintf
-#include <stdlib.h> // strtod
-#include <string.h> // strcasecmp
-#include "board/irq.h" // irq_disable
+#include <string.h> // memcpy
+#include "board/io.h" // readb
 #include "board/misc.h" // crc16_ccitt
 #include "board/pgm.h" // READP
 #include "command.h" // output_P
@@ -110,15 +107,23 @@ error:
     shutdown("Command parser error");
 }
 
+static uint8_t in_sendf;
+
 // Encode a message and transmit it
 void
 _sendf(uint8_t parserid, ...)
 {
+    if (readb(&in_sendf))
+        // This sendf call was made from an irq handler while the main
+        // code was already in sendf - just drop this sendf request.
+        return;
+    writeb(&in_sendf, 1);
+
     const struct command_encoder *cp = &command_encoders[parserid];
     uint8_t max_size = READP(cp->max_size);
     char *buf = console_get_output(max_size + MESSAGE_MIN);
     if (!buf)
-        return;
+        goto done;
     char *p = &buf[MESSAGE_HEADER_SIZE];
     if (max_size) {
         char *maxend = &p[max_size];
@@ -140,7 +145,10 @@ _sendf(uint8_t parserid, ...)
             case PT_int16:
             case PT_byte:
                 if (t >= PT_uint16)
-                    v = va_arg(args, int) & 0xffff;
+                    if (t == PT_int16)
+                        v = (int32_t)va_arg(args, int);
+                    else
+                        v = va_arg(args, unsigned int);
                 else
                     v = va_arg(args, uint32_t);
                 p = encode_int(p, v);
@@ -182,11 +190,20 @@ _sendf(uint8_t parserid, ...)
     *p++ = crc;
     *p++ = MESSAGE_SYNC;
     console_push_output(msglen);
+done:
+    writeb(&in_sendf, 0);
     return;
 error:
     shutdown("Message encode error");
 }
 
+static void
+sendf_shutdown(void)
+{
+    writeb(&in_sendf, 0);
+}
+DECL_SHUTDOWN(sendf_shutdown);
+
 
 /****************************************************************
  * Command routing
@@ -293,6 +310,5 @@ command_task(void)
         func(args);
     }
     console_pop_input(msglen);
-    return;
 }
 DECL_TASK(command_task);

src/endstop.c

@@ -4,8 +4,7 @@
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
-#include <stddef.h> // offsetof
-#include "basecmd.h" // alloc_oid
+#include "basecmd.h" // oid_alloc
 #include "board/gpio.h" // struct gpio
 #include "board/irq.h" // irq_disable
 #include "command.h" // DECL_COMMAND
@@ -15,12 +14,22 @@
 struct end_stop {
     struct timer time;
     uint32_t rest_time;
-    struct stepper *stepper;
     struct gpio_in pin;
-    uint8_t pin_value, flags;
+    uint8_t flags, stepper_count;
+    struct stepper *steppers[0];
 };
 
-enum { ESF_HOMING=1, ESF_REPORT=2 };
+enum { ESF_PIN_HIGH=1<<0, ESF_HOMING=1<<1, ESF_REPORT=1<<2 };
+
+static void noinline
+stop_steppers(struct end_stop *e)
+{
+    e->flags = ESF_REPORT;
+    uint8_t count = e->stepper_count;
+    while (count--)
+        if (e->steppers[count])
+            stepper_stop(e->steppers[count]);
+}
 
 // Timer callback for an end stop
 static uint_fast8_t
@@ -28,33 +37,46 @@ end_stop_event(struct timer *t)
 {
     struct end_stop *e = container_of(t, struct end_stop, time);
     uint8_t val = gpio_in_read(e->pin);
-    if (val != e->pin_value) {
+    if ((val ? ~e->flags : e->flags) & ESF_PIN_HIGH) {
+        // No match - reschedule for the next attempt
         e->time.waketime += e->rest_time;
         return SF_RESCHEDULE;
     }
-    // Stop stepper
-    e->flags = ESF_REPORT;
-    stepper_stop(e->stepper);
+    stop_steppers(e);
     return SF_DONE;
 }
 
 void
 command_config_end_stop(uint32_t *args)
 {
-    struct end_stop *e = alloc_oid(args[0], command_config_end_stop, sizeof(*e));
-    struct stepper *s = lookup_oid(args[3], command_config_stepper);
+    uint8_t stepper_count = args[3];
+    struct end_stop *e = oid_alloc(
+        args[0], command_config_end_stop
+        , sizeof(*e) + sizeof(e->steppers[0]) * stepper_count);
     e->time.func = end_stop_event;
-    e->stepper = s;
     e->pin = gpio_in_setup(args[1], args[2]);
+    e->stepper_count = stepper_count;
 }
 DECL_COMMAND(command_config_end_stop,
-             "config_end_stop oid=%c pin=%c pull_up=%c stepper_oid=%c");
+             "config_end_stop oid=%c pin=%c pull_up=%c stepper_count=%c");
+
+void
+command_end_stop_set_stepper(uint32_t *args)
+{
+    struct end_stop *e = oid_lookup(args[0], command_config_end_stop);
+    uint8_t pos = args[1];
+    if (pos >= e->stepper_count)
+        shutdown("Set stepper past maximum stepper count");
+    e->steppers[pos] = stepper_oid_lookup(args[2]);
+}
+DECL_COMMAND(command_end_stop_set_stepper,
+             "end_stop_set_stepper oid=%c pos=%c stepper_oid=%c");
 
 // Home an axis
 void
 command_end_stop_home(uint32_t *args)
 {
-    struct end_stop *e = lookup_oid(args[0], command_config_end_stop);
+    struct end_stop *e = oid_lookup(args[0], command_config_end_stop);
     sched_del_timer(&e->time);
     e->time.waketime = args[1];
     e->rest_time = args[2];
@@ -63,9 +85,8 @@ command_end_stop_home(uint32_t *args)
         e->flags = 0;
         return;
     }
-    e->pin_value = args[3];
-    e->flags = ESF_HOMING;
-    sched_timer(&e->time);
+    e->flags = ESF_HOMING | (args[3] ? ESF_PIN_HIGH : 0);
+    sched_add_timer(&e->time);
 }
 DECL_COMMAND(command_end_stop_home,
              "end_stop_home oid=%c clock=%u rest_ticks=%u pin_value=%c");
@@ -74,21 +95,19 @@ static void
 end_stop_report(uint8_t oid, struct end_stop *e)
 {
     irq_disable();
-    uint32_t position = stepper_get_position(e->stepper);
     uint8_t eflags = e->flags;
     e->flags &= ~ESF_REPORT;
     irq_enable();
 
-    sendf("end_stop_state oid=%c homing=%c pin=%c pos=%i"
-          , oid, !!(eflags & ESF_HOMING), gpio_in_read(e->pin)
-          , position - STEPPER_POSITION_BIAS);
+    sendf("end_stop_state oid=%c homing=%c pin=%c"
+          , oid, !!(eflags & ESF_HOMING), gpio_in_read(e->pin));
 }
 
 void
 command_end_stop_query(uint32_t *args)
 {
     uint8_t oid = args[0];
-    struct end_stop *e = lookup_oid(oid, command_config_end_stop);
+    struct end_stop *e = oid_lookup(oid, command_config_end_stop);
     end_stop_report(oid, e);
 }
 DECL_COMMAND(command_end_stop_query, "end_stop_query oid=%c");

src/generic/armcm_irq.c

@@ -0,0 +1,58 @@
+// Definitions for irq enable/disable on ARM Cortex-M processors
+//
+// Copyright (C) 2017  Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU GPLv3 license.
+
+#include "irq.h" // irqstatus_t
+#include "sched.h" // DECL_SHUTDOWN
+
+void
+irq_disable(void)
+{
+    asm volatile("cpsid i" ::: "memory");
+}
+
+void
+irq_enable(void)
+{
+    asm volatile("cpsie i" ::: "memory");
+}
+
+irqstatus_t
+irq_save(void)
+{
+    irqstatus_t flag;
+    asm volatile("mrs %0, primask" : "=r" (flag) :: "memory");
+    irq_disable();
+    return flag;
+}
+
+void
+irq_restore(irqstatus_t flag)
+{
+    asm volatile("msr primask, %0" :: "r" (flag) : "memory");
+}
+
+// Clear the active irq if a shutdown happened in an irq handler
+static void
+clear_active_irq(void)
+{
+    uint32_t psr;
+    asm volatile("mrs %0, psr" : "=r" (psr));
+    if (!(psr & 0x1ff))
+        // Shutdown did not occur in an irq - nothing to do.
+        return;
+    // Clear active irq status
+    psr = 1<<24; // T-bit
+    uint32_t temp;
+    asm volatile(
+        "  push { %1 }\n"
+        "  adr %0, 1f\n"
+        "  push { %0 }\n"
+        "  push { r0, r1, r2, r3, r12, lr }\n"
+        "  bx %2\n"
+        "1:\n"
+        : "=&r"(temp) : "r"(psr), "r"(0xfffffff9) : "cc");
+}
+DECL_SHUTDOWN(clear_active_irq);

src/generic/io.h

@@ -2,24 +2,34 @@
 #define __GENERIC_IO_H
 
 #include <stdint.h> // uint32_t
+#include "compiler.h" // barrier
 
 static inline void writel(void *addr, uint32_t val) {
+    barrier();
     *(volatile uint32_t *)addr = val;
 }
 static inline void writew(void *addr, uint16_t val) {
+    barrier();
     *(volatile uint16_t *)addr = val;
 }
 static inline void writeb(void *addr, uint8_t val) {
+    barrier();
     *(volatile uint8_t *)addr = val;
 }
 static inline uint32_t readl(const void *addr) {
-    return *(volatile const uint32_t *)addr;
+    uint32_t val = *(volatile const uint32_t *)addr;
+    barrier();
+    return val;
 }
 static inline uint16_t readw(const void *addr) {
-    return *(volatile const uint16_t *)addr;
+    uint16_t val = *(volatile const uint16_t *)addr;
+    barrier();
+    return val;
 }
 static inline uint8_t readb(const void *addr) {
-    return *(volatile const uint8_t *)addr;
+    uint8_t val = *(volatile const uint8_t *)addr;
+    barrier();
+    return val;
 }
 
 #endif // io.h

src/generic/misc.h

@@ -10,10 +10,9 @@ char *console_get_output(uint8_t len);
 void console_push_output(uint8_t len);
 
 uint32_t timer_from_us(uint32_t us);
-void timer_periodic(void);
+uint8_t timer_is_before(uint32_t time1, uint32_t time2);
 uint32_t timer_read_time(void);
-uint8_t timer_set_next(uint32_t next);
-uint8_t timer_try_set_next(uint32_t next);
+void timer_periodic(void);
 
 size_t alloc_maxsize(size_t reqsize);
 

src/generic/timer_irq.c

@@ -0,0 +1,99 @@
+// Generic interrupt based timer helper functions
+//
+// Copyright (C) 2017  Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU GPLv3 license.
+
+#include "autoconf.h" // CONFIG_CLOCK_FREQ
+#include "board/irq.h" // irq_disable
+#include "board/misc.h" // timer_from_us
+#include "board/timer_irq.h" // timer_dispatch_many
+#include "command.h" // shutdown
+#include "sched.h" // sched_timer_kick
+
+DECL_CONSTANT(CLOCK_FREQ, CONFIG_CLOCK_FREQ);
+
+// Return the number of clock ticks for a given number of microseconds
+uint32_t
+timer_from_us(uint32_t us)
+{
+    return us * (CONFIG_CLOCK_FREQ / 1000000);
+}
+
+// Return true if time1 is before time2.  Always use this function to
+// compare times as regular C comparisons can fail if the counter
+// rolls over.
+uint8_t
+timer_is_before(uint32_t time1, uint32_t time2)
+{
+    return (int32_t)(time1 - time2) < 0;
+}
+
+// Called by main code once every millisecond.  (IRQs disabled.)
+void
+timer_periodic(void)
+{
+}
+
+static uint32_t timer_repeat_until;
+#define TIMER_IDLE_REPEAT_TICKS timer_from_us(500)
+#define TIMER_REPEAT_TICKS timer_from_us(100)
+
+#define TIMER_MIN_TRY_TICKS timer_from_us(1)
+#define TIMER_DEFER_REPEAT_TICKS timer_from_us(5)
+
+// Reschedule timers after a brief pause to prevent task starvation
+static uint32_t noinline
+force_defer(uint32_t next)
+{
+    uint32_t now = timer_read_time();
+    if (timer_is_before(next + timer_from_us(1000), now))
+        shutdown("Rescheduled timer in the past");
+    timer_repeat_until = now + TIMER_REPEAT_TICKS;
+    return now + TIMER_DEFER_REPEAT_TICKS;
+}
+
+// Invoke timers - called from board irq code.
+uint32_t
+timer_dispatch_many(void)
+{
+    uint32_t tru = timer_repeat_until;
+    for (;;) {
+        // Run the next software timer
+        uint32_t next = sched_timer_dispatch();
+
+        uint32_t now = timer_read_time();
+        int32_t diff = next - now;
+        if (diff > (int32_t)TIMER_MIN_TRY_TICKS)
+            // Schedule next timer normally.
+            return next;
+
+        if (unlikely(timer_is_before(tru, now)))
+            // Too many repeat timers from a single interrupt - force a pause
+            return force_defer(next);
+
+        // Next timer in the past or near future - wait for it to be ready
+        irq_enable();
+        while (unlikely(diff > 0))
+            diff = next - timer_read_time();
+        irq_disable();
+    }
+}
+
+// Periodic background task that temporarily boosts priority of
+// timers.  This helps prioritize timers when tasks are idling.
+static void
+timer_task(void)
+{
+    irq_disable();
+    timer_repeat_until = timer_read_time() + TIMER_IDLE_REPEAT_TICKS;
+    irq_enable();
+}
+DECL_TASK(timer_task);
+
+static void
+timer_irq_shutdown(void)
+{
+    timer_repeat_until = timer_read_time() + TIMER_IDLE_REPEAT_TICKS;
+}
+DECL_SHUTDOWN(timer_irq_shutdown);

src/generic/timer_irq.h

@@ -0,0 +1,6 @@
+#ifndef __GENERIC_TIMER_IRQ_H
+#define __GENERIC_TIMER_IRQ_H
+
+uint32_t timer_dispatch_many(void);
+
+#endif // timer_irq.h

src/gpiocmds.c

@@ -4,11 +4,12 @@
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
-#include "basecmd.h" // alloc_oid
+#include "basecmd.h" // oid_alloc
 #include "board/gpio.h" // struct gpio_out
 #include "board/irq.h" // irq_disable
+#include "board/misc.h" // timer_is_before
 #include "command.h" // DECL_COMMAND
-#include "sched.h" // sched_timer
+#include "sched.h" // sched_add_timer
 
 
 /****************************************************************
@@ -43,7 +44,7 @@ digital_out_event(struct timer *timer)
 void
 command_config_digital_out(uint32_t *args)
 {
-    struct digital_out_s *d = alloc_oid(args[0], command_config_digital_out
+    struct digital_out_s *d = oid_alloc(args[0], command_config_digital_out
                                         , sizeof(*d));
     d->default_value = args[2];
     d->pin = gpio_out_setup(args[1], d->default_value);
@@ -56,12 +57,12 @@ DECL_COMMAND(command_config_digital_out,
 void
 command_schedule_digital_out(uint32_t *args)
 {
-    struct digital_out_s *d = lookup_oid(args[0], command_config_digital_out);
+    struct digital_out_s *d = oid_lookup(args[0], command_config_digital_out);
     sched_del_timer(&d->timer);
     d->timer.func = digital_out_event;
     d->timer.waketime = args[1];
     d->value = args[2];
-    sched_timer(&d->timer);
+    sched_add_timer(&d->timer);
 }
 DECL_COMMAND(command_schedule_digital_out,
              "schedule_digital_out oid=%c clock=%u value=%c");
@@ -117,7 +118,7 @@ soft_pwm_toggle_event(struct timer *timer)
         waketime += s->on_duration;
     else
         waketime += s->off_duration;
-    if (s->flags & SPF_CHECK_END && !sched_is_before(waketime, s->end_time)) {
+    if (s->flags & SPF_CHECK_END && !timer_is_before(waketime, s->end_time)) {
         // End of normal pulsing - next event loads new pwm settings
         s->timer.func = soft_pwm_load_event;
         waketime = s->end_time;
@@ -155,7 +156,7 @@ soft_pwm_load_event(struct timer *timer)
 void
 command_config_soft_pwm_out(uint32_t *args)
 {
-    struct soft_pwm_s *s = alloc_oid(args[0], command_config_soft_pwm_out
+    struct soft_pwm_s *s = oid_alloc(args[0], command_config_soft_pwm_out
                                      , sizeof(*s));
     s->cycle_time = args[2];
     s->pulse_time = s->cycle_time / 255;
@@ -171,7 +172,7 @@ DECL_COMMAND(command_config_soft_pwm_out,
 void
 command_schedule_soft_pwm_out(uint32_t *args)
 {
-    struct soft_pwm_s *s = lookup_oid(args[0], command_config_soft_pwm_out);
+    struct soft_pwm_s *s = oid_lookup(args[0], command_config_soft_pwm_out);
     uint32_t time = args[1];
     uint8_t value = args[2];
     uint8_t next_flags = SPF_CHECK_END | SPF_HAVE_NEXT;
@@ -189,20 +190,20 @@ command_schedule_soft_pwm_out(uint32_t *args)
             next_flags |= SPF_NEXT_CHECK_END;
     }
     irq_disable();
-    if (s->flags & SPF_CHECK_END && sched_is_before(s->end_time, time))
+    if (s->flags & SPF_CHECK_END && timer_is_before(s->end_time, time))
         shutdown("next soft pwm extends existing pwm");
     s->end_time = time;
     s->next_on_duration = next_on_duration;
     s->next_off_duration = next_off_duration;
     s->flags |= next_flags;
-    if (s->flags & SPF_TOGGLING && sched_is_before(s->timer.waketime, time)) {
+    if (s->flags & SPF_TOGGLING && timer_is_before(s->timer.waketime, time)) {
         // soft_pwm_toggle_event() will schedule a load event when ready
     } else {
         // Schedule the loading of the pwm parameters at the requested time
         sched_del_timer(&s->timer);
         s->timer.waketime = time;
         s->timer.func = soft_pwm_load_event;
-        sched_timer(&s->timer);
+        sched_add_timer(&s->timer);
     }
     irq_enable();
 }