docs: Update release notes for v0.6.0 release

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

.travis.yml

@@ -0,0 +1,13 @@
+# This is a travis-ci.org continuous integration configuration file.
+language: c
+
+addons:
+    apt:
+        packages:
+            - gcc-avr
+            - avr-libc
+            - wget
+
+install: ./scripts/travis-install.sh
+
+script: ./scripts/travis-build.sh

Makefile

@@ -1,6 +1,6 @@
 # Klipper build system
 #
-# 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.
 
@@ -22,7 +22,7 @@ OBJCOPY=$(CROSS_PREFIX)objcopy
 OBJDUMP=$(CROSS_PREFIX)objdump
 STRIP=$(CROSS_PREFIX)strip
 CPP=cpp
-PYTHON=python
+PYTHON=python2
 
 # Source files
 src-y =
@@ -32,18 +32,15 @@ dirs-y = src
 cc-option=$(shell if test -z "`$(1) $(2) -S -o /dev/null -xc /dev/null 2>&1`" \
     ; then echo "$(2)"; else echo "$(3)"; fi ;)
 
-CFLAGS-y := -I$(OUT) -Isrc -I$(OUT)board-generic/ -O2 -MD -g \
+CFLAGS := -I$(OUT) -Isrc -I$(OUT)board-generic/ -O2 -MD -g \
     -Wall -Wold-style-definition $(call cc-option,$(CC),-Wtype-limits,) \
     -ffunction-sections -fdata-sections
-CFLAGS-y += -flto -fwhole-program -fno-use-linker-plugin
+CFLAGS += -flto -fwhole-program -fno-use-linker-plugin
 
-LDFLAGS-y := -Wl,--gc-sections -fno-whole-program
+CFLAGS_klipper.elf = $(CFLAGS) -Wl,--gc-sections
 
 CPPFLAGS = -I$(OUT) -P -MD -MT $@
 
-CFLAGS = $(CFLAGS-y)
-LDFLAGS = $(LDFLAGS-y)
-
 # Default targets
 target-y := $(OUT)klipper.elf
 
@@ -77,23 +74,18 @@ $(OUT)board-link: $(KCONFIG_CONFIG)
 	$(Q)mkdir -p $(OUT)board-generic
 	$(Q)ln -Tsf $(PWD)/src/generic $(OUT)board-generic/board
 
-$(OUT)declfunc.lds: src/declfunc.lds.S
-	@echo "  Precompiling $@"
-	$(Q)$(CPP) $(CPPFLAGS) -D__ASSEMBLY__ $< -o $@
+$(OUT)%.o.ctr: $(OUT)%.o
+	$(Q)$(OBJCOPY) -j '.compile_time_request' -O binary $^ $@
 
-$(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 $@
-
-$(OUT)compile_time_request.o: $(OUT)klipper.o ./scripts/buildcommands.py
+$(OUT)compile_time_request.o: $(patsubst %.c, $(OUT)src/%.o.ctr,$(src-y)) ./scripts/buildcommands.py
 	@echo "  Building $@"
-	$(Q)$(OBJCOPY) -j '.compile_time_request' -O binary $< $(OUT)klipper.o.compile_time_request
-	$(Q)$(PYTHON) ./scripts/buildcommands.py -d $(OUT)klipper.dict $(OUT)klipper.o.compile_time_request $(OUT)compile_time_request.c
+	$(Q)cat $(patsubst %.c, $(OUT)src/%.o.ctr,$(src-y)) > $(OUT)klipper.compile_time_request
+	$(Q)$(PYTHON) ./scripts/buildcommands.py -d $(OUT)klipper.dict -t "$(CC);$(AS);$(LD);$(OBJCOPY);$(OBJDUMP);$(STRIP)" $(OUT)klipper.compile_time_request $(OUT)compile_time_request.c
 	$(Q)$(CC) $(CFLAGS) -c $(OUT)compile_time_request.c -o $@
 
-$(OUT)klipper.elf: $(OUT)klipper.o $(OUT)compile_time_request.o
+$(OUT)klipper.elf: $(patsubst %.c, $(OUT)src/%.o,$(src-y)) $(OUT)compile_time_request.o
 	@echo "  Linking $@"
-	$(Q)$(CC) $(CFLAGS) $(LDFLAGS) $^ -o $@
+	$(Q)$(CC) $^ $(CFLAGS_klipper.elf) -o $@
 
 ################ Kconfig rules
 

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: analog7
 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 +1,81 @@
+# 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: ^ar3
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+# 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: ^ar14
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: ar46
+dir_pin: ar48
+enable_pin: !ar62
+step_distance: .0025
+endstop_pin: ^ar18
+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

@@ -9,48 +9,58 @@
 
 # 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
 enable_pin: !ar38
 step_distance: .01
 endstop_pin: ^ar2
-homing_speed: 50.0
+homing_speed: 50
 position_endstop: 297.05
-position_max: 297.55
+#   Distance (in mm) between the nozzle and the bed when the nozzle is
+#   in the center of the build area and the endstop triggers. This
+#   parameter must be provided for stepper_a; for stepper_b and
+#   stepper_c this parameter defaults to the value specified for
+#   stepper_a.
+arm_length: 333.0
+#   Length (in mm) of the diagonal rod that connects this tower to the
+#   print head. This parameter must be provided for stepper_a; for
+#   stepper_b and stepper_c this parameter defaults to the value
+#   specified for stepper_a.
+#angle:
+#   This option specifies the angle (in degrees) that the tower is
+#   at. The default is 210 for stepper_a, 330 for stepper_b, and 90
+#   for stepper_c.
 
 # The stepper_b section describes the stepper controlling the front
-# right tower (at 330 degrees)
+# right tower (at 330 degrees).
 [stepper_b]
 step_pin: ar60
 dir_pin: ar61
 enable_pin: !ar56
 step_distance: .01
 endstop_pin: ^ar15
-position_endstop: 297.05
 
 # The stepper_c section describes the stepper controlling the rear
-# tower (at 90 degrees)
+# tower (at 90 degrees).
 [stepper_c]
 step_pin: ar46
 dir_pin: ar48
 enable_pin: !ar62
 step_distance: .01
 endstop_pin: ^ar19
-position_endstop: 297.05
 
 [extruder]
 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
@@ -60,36 +70,62 @@ 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
 
-# Extruder print fan (omit section if fan not present)
+# Print cooling 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 parameter must be specified.
 max_accel: 3000
-max_z_velocity: 200
+#   Maximum acceleration (in mm/s^2) of the toolhead relative to the
+#   print. This parameter must be specified.
+max_z_velocity: 150
 #   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).
-delta_arm_length: 333.0
-#   Length (in mm) of the diagonal rods that connect the linear axes
-#   to the print head
+#   than other moves on a delta printer). The default is to use
+#   max_velocity for max_z_velocity.
+#minimum_z_position: 0
+#   The minimum Z position that the user may command the head to move
+#   to.  The default is 0.
 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.
+
+# The delta_calibrate section enables a DELTA_CALIBRATE extended
+# g-code command that can calibrate the tower endstop positions and
+# angles.
+[delta_calibrate]
+radius: 50
+#   Radius (in mm) of the area that may be probed. This is typically
+#   the size of the printer bed. This parameter must be provided.
+#speed: 50
+#   The speed (in mm/s) of non-probing moves during the
+#   calibration. The default is 50.
+#horizontal_move_z: 5
+#   The height (in mm) that the head should be commanded to move to
+#   just prior to starting a probe operation. The default is 5.
+#manual_probe:
+#   If true, then DELTA_CALIBRATE will perform manual probing. If
+#   false, then a PROBE command will be run at each probe
+#   point. Manual probing is accomplished by manually jogging the Z
+#   position of the print head at each probe point and then issuing a
+#   NEXT extended g-code command to record the position at that
+#   point. The default is false if a [probe] config section is present
+#   and true otherwise.

config/example-extras.cfg

@@ -0,0 +1,400 @@
+# This file serves as documentation for config parameters of
+# additional devices that may be configured on a printer. The snippets
+# in this file may be copied into the main printer.cfg file. See the
+# "example.cfg" file for description of common config parameters.
+#
+# Note, where an extra config section creates additional pins, the
+# section defining the pins must be listed in the config file before
+# any sections using those pins.
+
+
+# Z height probe. One may define this section to enable Z height
+# probing hardware. When this section is enabled, PROBE and
+# QUERY_PROBE extended g-code commands become available. The probe
+# section also creates a virtual probe:z_virtual_endstop pin. One may
+# set the stepper_z endstop_pin to this virtual pin on cartesian style
+# printers that use the probe in place of a z endstop.
+#[probe]
+#pin: ar15
+#   Probe detection pin. This parameter must be provided.
+#z_offset:
+#   The distance (in mm) between the bed and the nozzle when the probe
+#   triggers. This parameter must be provided.
+#speed: 5.0
+#   Speed (in mm/s) of the Z axis when probing. The default is 5mm/s.
+#activate_gcode:
+#   A list of G-Code commands (one per line) to execute prior to each
+#   probe attempt. This may be useful if the probe needs to be
+#   activated in some way. The default is to not run any special
+#   G-Code commands on activation.
+#deactivate_gcode:
+#   A list of G-Code commands (one per line) to execute after each
+#   probe attempt completes. The default is to not run any special
+#   G-Code commands on deactivation.
+
+
+# Bed tilt compensation. One may define a [bed_tilt] config section to
+# enable move transformations that account for a tilted bed.
+#[bed_tilt]
+#x_adjust: 0
+#   The amount to add to each move's Z height for each mm on the X
+#   axis. The default is 0.
+#y_adjust: 0
+#   The amount to add to each move's Z height for each mm on the Y
+#   axis. The default is 0.
+# The remaining parameters control a BED_TILT_CALIBRATE extended
+# g-code command that may be used to calibrate appropriate x and y
+# adjustment parameters.
+#points:
+#    A newline separated list of X,Y points that should be probed
+#    during a BED_TILT_CALIBRATE command. The default is to not enable
+#    the command.
+#speed: 50
+#   The speed (in mm/s) of non-probing moves during the
+#   calibration. The default is 50.
+#horizontal_move_z: 5
+#   The height (in mm) that the head should be commanded to move to
+#   just prior to starting a probe operation. The default is 5.
+#manual_probe:
+#   If true, then BED_TILT_CALIBRATE will perform manual probing. If
+#   false, then a PROBE command will be run at each probe
+#   point. Manual probing is accomplished by manually jogging the Z
+#   position of the print head at each probe point and then issuing a
+#   NEXT extended g-code command to record the position at that
+#   point. The default is false if a [probe] config section is present
+#   and true otherwise.
+
+
+# In a multi-extruder printer add an additional extruder section for
+# each additional extruder. The additional extruder sections should be
+# named "extruder1", "extruder2", "extruder3", and so on. See the
+# "extruder" section in example.cfg for a description of available
+# parameters.
+#[extruder1]
+#step_pin: ar36
+#dir_pin: ar34
+#...
+#shared_heater:
+#   If this extruder uses the same heater already defined for another
+#   extruder then place the name of that extruder here.  For example,
+#   should extruder3 and extruder4 share a heater then the extruder3
+#   config section should define the heater and the extruder4 section
+#   should specify "shared_heater: extruder3". The default is to not
+#   reuse an existing heater.
+#deactivate_gcode:
+#   A list of G-Code commands (one per line) to execute on a G-Code
+#   tool change command (eg, "T1") that deactivates this extruder and
+#   activates some other extruder. It only makes sense to define this
+#   section on multi-extruder printers. The default is to not run any
+#   special G-Code commands on deactivation.
+#activate_gcode:
+#   A list of G-Code commands (one per line) to execute on a G-Code
+#   tool change command (eg, "T0") that activates this extruder. It
+#   only makes sense to define this section on multi-extruder
+#   printers. The default is to not run any special G-Code commands on
+#   activation.
+
+
+# Support for cartesian printers with dual carriages on a single
+# axis. The active carriage is set via the SET_DUAL_CARRIAGE extended
+# g-code command. The "SET_DUAL_CARRIAGE CARRIAGE=1" command will
+# activate the carriage defined in this section (CARRIAGE=0 will
+# return activation to the primary carriage). Dual carriage support is
+# typically combined with extra extruders - use the SET_DUAL_CARRIAGE
+# command in the activate_gcode / deactivate_gcode section of the
+# appropriate extruder. Be sure to also use that mechanism to park the
+# carriages during deactivation.
+#[dual_carriage]
+#axis:
+#   The axis this extra carriage is on (either x or y). This parameter
+#   must be provided.
+#step_pin:
+#dir_pin:
+#enable_pin:
+#step_distance:
+#endstop_pin:
+#position_endstop:
+#position_min:
+#position_max:
+#   See the example.cfg for the definition of the above parameters.
+
+
+# Heater and temperature sensor verification. Heater verification is
+# automatically enabled for each heater that is configured on the
+# printer. Use verify_heater sections to change the default settings.
+#[verify_heater heater_config_name]
+#heating_gain: 2
+#   The minimum temperature (in Celsius) that the heater must increase
+#   by when approaching a new target temperature. The default is 2.
+#check_gain_time:
+#   The amount of time (in seconds) that the heating_gain must be met
+#   in before an error is raised. The default is 20 seconds for
+#   extruders and 60 seconds for heater_bed.
+#hysteresis: 5
+#   The difference between the target temperature and the current
+#   temperature for the heater to be considered within range of the
+#   target temperature. The default is 5.
+#max_error: 120
+#   The maximum temperature difference a heater that falls outside the
+#   target temperature range may accumulate before an error is
+#   raised. For example, if the target temperature is 200, the
+#   hysteresis is 5, the max_error is 120, and the temperature is
+#   reported at 185 degrees for 12 seconds then an error would be
+#   raised (or 24 seconds at 190, or 120 seconds at 194, etc.). The
+#   default is 120.
+
+
+# Multi-stepper axes. On a cartesian style printer, the stepper
+# controlling a given axis may have additional config blocks defining
+# steppers that should be stepped in concert with the primary
+# stepper. One may define any number of sections with a numeric suffix
+# starting at 1 (for example, "stepper_z1", "stepper_z2", etc.).
+#[stepper_z1]
+#step_pin: ar36
+#dir_pin: ar34
+#enable_pin: !ar30
+#step_distance: .005
+#   See the example.cfg for the definition of the above parameters.
+#endstop_pin: ^ar19
+#   If an endstop_pin is defined for the additional stepper then the
+#   stepper will home until the endstop is triggered. Otherwise, the
+#   endstop will home until the endstop on the primary stepper for the
+#   axis is triggered.
+
+
+# Stepper phase adjusted endstops. The following additional parameters
+# may be added to a stepper axis definition to improve the accuracy of
+# endstop switches.
+#[stepper_z]
+#homing_stepper_phases:
+#   One may set this to the number of phases of the stepper motor
+#   driver (which is the number of micro-steps multiplied by
+#   four). This parameter must be provided if using stepper phase
+#   adjustments.
+#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
+#   then set this to 0.200 for 200um). The default is
+#   homing_stepper_phases*step_distance.
+#homing_endstop_phase:
+#   This specifies the phase of the stepper motor driver to expect
+#   when hitting the endstop. Only set this value if one is sure the
+#   stepper motor driver is reset every time the mcu is reset. If this
+#   is not set, then the stepper phase will be detected on the first
+#   home and that phase will be used on all subsequent homes.
+#homing_endstop_align_zero: False
+#   If true then the code will arrange for the zero position on the
+#   axis to occur at a full step on the stepper motor. (If used on the
+#   Z axis and the print layer height is a multiple of a full step
+#   distance then every layer will occur on a full step.) The default
+#   is False.
+
+
+# Heater cooling fans (one may define any number of sections with a
+# "heater_fan" prefix). A "heater fan" is a fan that will be enabled
+# whenever its associated heater is active. In the event of an MCU
+# software error the heater_fan will be set to its max_power.
+#[heater_fan my_nozzle_fan]
+# See the "fan" section for fan configuration parameters.
+#pin: ar4
+# The remaining variables are specific to heater_fan.
+#heater: extruder
+#   Name of the config section defining the heater that this fan is
+#   associated with.  The default is "extruder".
+#heater_temp: 50.0
+#   A temperature (in Celsius) that the heater must drop below before
+#   the fan is disabled. The default is 50 Celsius.
+#fan_speed:
+#   The fan speed (expressed as a value from 0.0 to 1.0) that the fan
+#   will be set to when its associated heater is enabled. The default
+#   is max_power.
+
+
+# Additional micro-controllers (one may define any number of sections
+# with an "mcu" prefix). Additional micro-controllers introduce
+# additional pins that may be configured as heaters, steppers, fans,
+# etc.. For example, if an "[mcu extra_mcu]" section is introduced,
+# then pins such as "extra_mcu:ar9" may then be used elsewhere in the
+# config (where "ar9" is a hardware pin name or alias name on the
+# given mcu).
+#[mcu my_extra_mcu]
+# See the "mcu" section in example.cfg for configuration parameters.
+
+
+# Servos (one may define any number of sections with a "servo"
+# prefix). The servos may be controlled using the SET_SERVO g-code
+# command. For example: SET_SERVO SERVO=my_servo ANGLE=180
+#[servo my_servo]
+#pin: ar7
+#   PWM output pin controlling the servo. This parameter must be
+#   provided.
+#maximum_servo_angle: 180
+#   The maximum angle (in degrees) that this servo can be set to. The
+#   default is 180 degrees.
+#minimum_pulse_width: 0.001
+#   The minimum pulse width time (in seconds). This should correspond
+#   with an angle of 0 degrees. The default is 0.001 seconds.
+#maximum_pulse_width: 0.002
+#   The maximum pulse width time (in seconds). This should correspond
+#   with an angle of maximum_servo_angle. The default is 0.002
+#   seconds.
+
+
+# Statically configured digital output pins (one may define any number
+# of sections with a "static_digital_output" prefix). Pins configured
+# here will be setup as a GPIO output during MCU configuration. They
+# can not be changed at run-time.
+#[static_digital_output my_output_pins]
+#pins:
+#   A comma separated list of pins to be set as GPIO output pins. The
+#   pin will be set to a high level unless the pin name is prefaced
+#   with "!". This parameter must be provided.
+
+
+# Run-time configurable output pins (one may define any number of
+# sections with an "output_pin" prefix). Pins configured here will be
+# setup as output pins and one may modify them at run-time using the
+# "SET_PIN PIN=my_pin VALUE=.1" extended g-code command.
+#[output_pin my_pin]
+#pin:
+#   The pin to configure as an output. This parameter must be
+#   provided.
+#pwm: False
+#   Set if the output pin should be capable of
+#   pulse-width-modulation. If this is true, the value fields should
+#   be between 0 and 1; if it is false the value fields should be
+#   either 0 or 1. The default is False.
+#static_value:
+#   If this is set, then the pin is assigned to this value at startup
+#   and the pin can not be changed during runtime. A static pin uses
+#   slightly less ram in the micro-controller. The default is to use
+#   runtime configuration of pins.
+#value:
+#   The value to initially set the pin to during MCU
+#   configuration. The default is 0 (for low voltage).
+#shutdown_value:
+#   The value to set the pin to on an MCU shutdown event. The default
+#   is 0 (for low voltage).
+#cycle_time: 0.100
+#   The amount of time (in seconds) per PWM cycle. It is recommended
+#   this be 10 milliseconds or greater when using software based
+#   PWM. The default is 0.100 seconds for pwm pins.
+#hardware_pwm: False
+#   Enable this to use hardware PWM instead of software PWM. The
+#   default is False.
+#scale:
+#   This parameter can be used to alter how the 'value' and
+#   'shutdown_value' parameters are interpreted for pwm pins. If
+#   provided, then the 'value' parameter should be between 0.0 and
+#   'scale'. This may be useful when configuring a PWM pin that
+#   controls a stepper voltage reference. The 'scale' can be set to
+#   the equivalent stepper amperage if the PWM were fully enabled, and
+#   then the 'value' parameter can be specified using the desired
+#   amperage for the stepper. The default is to not scale the 'value'
+#   parameter.
+
+
+# Multiple pin outputs (one may define any number of sections with a
+# "multi_pin" prefix). A multi_pin output creates an internal pin
+# alias that can modify multiple output pins each time the alias pin
+# is set. For example, one could define a "[multi_pin my_fan]" object
+# containing two pins and then set "pin=multi_pin:my_fan" in the
+# "[fan]" section - on each fan change both output pins would be
+# updated. These aliases may not be used with stepper motor pins.
+#[multi_pin my_multi_pin]
+#pins:
+#   A comma separated list of pins associated with this alias. This
+#   parameter must be provided.
+
+
+# Statically configured AD5206 digipots connected via SPI bus (one may
+# define any number of sections with an "ad5206" prefix).
+#[ad5206 my_digipot]
+#enable_pin:
+#   The pin corresponding to the AD5206 chip select line. This pin
+#   will be set to low at the start of SPI messages and raised to high
+#   after the message completes. This parameter must be provided.
+#channel_1:
+#channel_2:
+#channel_3:
+#channel_4:
+#channel_5:
+#channel_6:
+#   The value to statically set the given AD5206 channel to. This is
+#   typically set to a number between 0.0 and 1.0 with 1.0 being the
+#   highest resistance and 0.0 being the lowest resistance. However,
+#   the range may be changed with the 'scale' parameter (see
+#   below). If a channel is not specified then it is left
+#   unconfigured.
+#scale:
+#   This parameter can be used to alter how the 'channel_x' parameters
+#   are interpreted. If provided, then the 'channel_x' parameters
+#   should be between 0.0 and 'scale'. This may be useful when the
+#   AD5206 is used to set stepper voltage references. The 'scale' can
+#   be set to the equivalent stepper amperage if the AD5206 were at
+#   its highest resistance, and then the 'channel_x' parameters can be
+#   specified using the desired amperage value for the stepper. The
+#   default is to not scale the 'channel_x' parameters.
+
+
+# Homing override. One may use this mechanism to run a series of
+# g-code commands in place of a G28 found in the normal g-code input.
+# This may be useful on printers that require a specific procedure to
+# home the machine.
+#[homing_override]
+#gcode:
+#   A list of G-Code commands (one per line) to execute in place of
+#   all G28 commands found in the normal g-code input. If a G28 is
+#   contained in this list of commands then it will invoke the normal
+#   homing procedure for the printer. The commands listed here must
+#   home all axes. This parameter must be provided.
+#set_position_x:
+#set_position_y:
+#set_position_z:
+#   If specified, the printer will assume the axis is at the specified
+#   position prior to running the above g-code commands. Setting this
+#   disables homing checks for that axis. This may be useful if the
+#   head must move prior to invoking the normal G28 mechanism for an
+#   axis. The default is to not force a position for an axis.
+
+
+# A virtual sdcard may be useful if the host machine is not fast
+# enough to run OctoPrint well. It allows the Klipper host software to
+# directly print gcode files stored in a directory on the host using
+# standard sdcard G-Code commands (eg, M24).
+#[virtual_sdcard]
+#path: ~/.octoprint/uploads/
+#   The path of the local directory on the host machine to look for
+#   g-code files. This is a read-only directory (sdcard file writes
+#   are not supported). One may point this to OctoPrint's upload
+#   directory (generally ~/.octoprint/uploads/ ). This parameter must
+#   be provided.
+
+
+# Support for a display attached to the micro-controller.
+#[display]
+#lcd_type:
+#    The type of LCD chip in use. This may be either "hd44780" (which
+#    is used in "RepRapDiscount 2004 Smart Controller" type displays)
+#    or "st7920" (which is used in "RepRapDiscount 12864 Full Graphic
+#    Smart Controller" type displays). This parameter must be
+#    provided.
+#rs_pin:
+#e_pin:
+#d4_pin:
+#d5_pin:
+#d6_pin:
+#d7_pin:
+#    The pins connected to an hd44780 type lcd. These parameters must
+#    be provided when using an hd44780 display.
+#cs_pin:
+#sclk_pin:
+#sid_pin:
+#    The pins connected to an st7920 type lcd. These parameters must
+#    be provided when using an st7920 display.
+
+
+# Replicape support - see the generic-replicape.cfg file for further
+# details.
+#[replicape]

config/example-multi-mcu.cfg

@@ -0,0 +1,87 @@
+# This file contains an example configuration with three
+# micro-controllers simultaneously controlling a single printer.
+
+# See both the example.cfg and example-extras.cfg file for a
+# description of available parameters.
+
+
+# The main micro-controller is used as the timing source for all the
+# micro-controllers on the printer. Typically, both the X and Y axes
+# are connected to the main micro-controller.
+[mcu]
+serial: /dev/ttyACM0
+pin_map: arduino
+
+# The "zboard" micro-controller will be used to control the Z axis.
+[mcu zboard]
+serial: /dev/ttyACM1
+pin_map: arduino
+
+# The "auxboard" micro-controller will be used to control the heaters.
+[mcu auxboard]
+serial: /dev/ttyACM2
+pin_map: arduino
+
+[stepper_x]
+step_pin: ar54
+dir_pin: ar55
+enable_pin: !ar38
+step_distance: .0125
+endstop_pin: ^ar3
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_y]
+step_pin: ar60
+dir_pin: !ar61
+enable_pin: !ar56
+step_distance: .0125
+endstop_pin: ^ar14
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: zboard:ar46
+dir_pin: zboard:ar48
+enable_pin: !zboard:ar62
+step_distance: .0025
+endstop_pin: ^zboard:ar18
+position_endstop: 0.5
+position_max: 200
+
+[extruder]
+step_pin: auxboard:ar26
+dir_pin: auxboard:ar28
+enable_pin: !auxboard:ar24
+step_distance: .002
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: auxboard:ar10
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: auxboard:analog13
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: auxboard:ar8
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: auxboard:analog14
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: auxboard:ar9
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100

config/example.cfg

@@ -1,6 +1,9 @@
 # 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. Only common config sections are described here - see the
+# "example-extras.cfg" file for configuring less common devices.
 
 # DO NOT COPY THIS FILE WITHOUT CAREFULLY READING AND UPDATING IT
 # FIRST. Incorrectly configured parameters may cause damage.
@@ -16,76 +19,66 @@
 
 
 # The stepper_x section is used to describe the stepper controlling
-# the X axis in a cartesian robot
+# the X axis in a cartesian robot.
 [stepper_x]
-step_pin: ar29
-#   Step GPIO pin (triggered high)
-dir_pin: !ar28
-#   Direction GPIO pin (high indicates positive direction)
-enable_pin: !ar25
-#   Enable pin (default is enable high; use ! to indicate enable low)
+step_pin: ar54
+#   Step GPIO pin (triggered high). This parameter must be provided.
+dir_pin: ar55
+#   Direction GPIO pin (high indicates positive direction). This
+#   parameter must be provided.
+enable_pin: !ar38
+#   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
-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
-#   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
-#   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
-#   then set this to 0.200 for 200um). This setting is used with
-#   homing_stepper_phases and is only useful if that parameter is also
-#   configured.
-#homing_endstop_phase: 0
-#   This specifies the phase of the stepper motor driver to expect
-#   when hitting the endstop. This setting is only meaningful if
-#   homing_stepper_phases is also set. Only set this value if one is
-#   sure the stepper motor driver is reset every time the mcu is
-#   reset. If this is not set, but homing_stepper_phases is set, then
-#   the stepper phase will be detected on the first home and that
-#   phase will be used on all subsequent homes.
-position_min: -0.25
+#   Distance in mm that each step causes the axis to travel. This
+#   parameter must be provided.
+endstop_pin: ^ar3
+#   Endstop switch detection pin. This parameter must be provided for
+#   the X, Y, and Z steppers on cartesian style printers.
+#position_min: 0
 #   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.
+#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:
+#   If true, homing will cause the stepper to move in a positive
+#   direction (away from zero); if false, home towards zero. The
+#   default is true if position_endstop is near position_max and false
+#   if near position_min.
 
 # 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
-# stepper_x section
+# stepper_x section.
 [stepper_y]
-step_pin: ar27
-dir_pin: ar26
-enable_pin: !ar25
+step_pin: ar60
+dir_pin: !ar61
+enable_pin: !ar56
 step_distance: .0225
-endstop_pin: ^ar1
-position_min: -0.25
+endstop_pin: ^ar14
 position_endstop: 0
 position_max: 200
 
 # The stepper_z section is used to describe the stepper controlling
 # the Z axis in a cartesian robot. It has the same settings as the
-# stepper_x section
+# stepper_x section.
 [stepper_z]
-step_pin: ar23
-dir_pin: !ar22
-enable_pin: !ar25
+step_pin: ar46
+dir_pin: ar48
+enable_pin: !ar62
 step_distance: .005
-endstop_pin: ^ar2
-position_min: 0.1
+endstop_pin: ^ar18
 position_endstop: 0.5
 position_max: 200
 
@@ -93,119 +86,209 @@ position_max: 200
 # controlling the printer extruder and the heater parameters for the
 # nozzle. The stepper configuration has the same settings as the
 # stepper_x section and the heater configuration has the same settings
-# as the heater_bed section
+# as the heater_bed section (described below).
 [extruder]
-step_pin: ar19
-dir_pin: ar18
-enable_pin: !ar25
+step_pin: ar26
+dir_pin: ar28
+enable_pin: !ar24
 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). This setting prevents excessive amounts of extrusion during
+#   relatively small XY moves. 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
-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
+#   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: ar10
+#   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", "NTC 100K beta 3950", or "AD595". This parameter
+#   must be provided.
+sensor_pin: analog13
+#   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.
+#pwm_cycle_time: 0.100
+#   Time in seconds for each software PWM cycle of the heater. It is
+#   not recommended to set this unless there is an electrical
+#   requirement to switch the heater faster than 10 times a second.
+#   The default is 0.100 seconds.
+#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)
 max_temp: 210
-#   Maximum temperature (mcu will shutdown if temperature is above
-#   this value)
+#   The maximum range of valid temperatures (in Celsius) that the
+#   heater must remain within. This controls a safety feature
+#   implemented in the micro-controller code - should the measured
+#   temperature ever fall outside this range then the micro-controller
+#   will go into a shutdown state. This check can help detect some
+#   heater and sensor hardware failures. Set this range just wide
+#   enough so that reasonable temperatures do not result in an
+#   error. These parameters 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
+heater_pin: ar8
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog14
 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)
+# Print cooling fan (omit section if fan not present).
 [fan]
-pin: ar14
-#   PWM output pin controlling the heater
-hard_pwm: 1
-#   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
+pin: ar9
+#   PWM output pin controlling the fan. This parameter must be
+#   provided.
+#max_power: 1.0
+#   The maximum power (expressed as a value from 0.0 to 1.0) that the
+#   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 fan. The default is 1.0.
+#cycle_time: 0.010
+#   The amount of time (in seconds) for each PWM power cycle to the
+#   fan. It is recommended this be 10 milliseconds or greater when
+#   using software based PWM. The default is 0.010 seconds.
+#hardware_pwm: False
+#   Enable this to use hardware PWM instead of software PWM. The
+#   default is False.
+#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
+# 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
-custom:
-#   This option may be used to specify a set of custom
-#   micro-controller commands to be sent at the start of the
-#   connection. It may be used to configure the initial settings of
-#   LEDs, to configure micro-stepping pins, to configure a digipot,
-#   etc.
+#   This option may be used to enable Arduino pin name aliases. The
+#   default is to not enable the aliases.
+#restart_method:
+#   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) 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' if the micro-controller communicates over a serial port,
+#   'command' otherwise.
 
-# The printer section controls high level printer settings
+# 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.
+
+
+# Looking for more options? Check the example-extras.cfg file.

config/generic-cramps.cfg

@@ -0,0 +1,86 @@
+# This file contains an example configuration for a Beaglebone PRU
+# micro-controller attached to a CRAMPS board.
+
+# THIS FILE HAS NOT BEEN TESTED - PROCEED WITH CAUTION!
+
+# NOTE: Klipper does not alter the input/output state of the
+# Beaglebone pins and it does not control their pull-up resistors.  In
+# order to set the pin state one must use a "device tree overlay" or
+# use the config-pin program.
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: P8_13
+dir_pin: P8_12
+enable_pin: !P9_14
+step_distance: .0125
+endstop_pin: ^P8_8
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_y]
+step_pin: P8_15
+dir_pin: P8_14
+enable_pin: !P9_14
+step_distance: .0125
+endstop_pin: ^P8_10
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: P8_19
+dir_pin: P8_18
+enable_pin: !P9_14
+step_distance: .0025
+endstop_pin: ^P9_13
+position_endstop: 0
+position_max: 200
+
+[extruder]
+step_pin: P9_16
+dir_pin: P9_12
+enable_pin: !P9_14
+step_distance: .002
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: P9_15
+sensor_type: EPCOS 100K B57560G104F
+pullup_resistor: 2000
+sensor_pin: P9_36
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: P8_11
+sensor_type: EPCOS 100K B57560G104F
+pullup_resistor: 2000
+sensor_pin: P9_33
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: P9_41
+
+[mcu]
+serial: /dev/rpmsg_pru30
+pin_map: beaglebone
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100
+
+[output_pin machine_enable]
+pin: P9_23
+value: 1
+shutdown_value: 0

config/generic-melzi.cfg

@@ -0,0 +1,79 @@
+# This file contains common pin mappings for Melzi v2.0 boards. To use
+# this config, the firmware should be compiled for the AVR
+# atmega1284p.
+
+# Note, a number of Melzi boards are shipped without a bootloader. In
+# that case, an external programmer will be needed to flash a
+# bootloader to the board (for example, see
+# http://www.instructables.com/id/Flashing-a-Bootloader-to-the-CR-10/
+# ). Once that is done, one should be able to use the standard "make
+# flash" command to flash Klipper.
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: PD7
+dir_pin: PC5
+enable_pin: !PD6
+step_distance: .0125
+endstop_pin: ^!PC2
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_y]
+step_pin: PC6
+dir_pin: PC7
+enable_pin: !PD6
+step_distance: .0125
+endstop_pin: ^!PC3
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: PB3
+dir_pin: !PB2
+enable_pin: !PA5
+step_distance: .0025
+endstop_pin: ^!PC4
+position_endstop: 0.5
+position_max: 200
+
+[extruder]
+step_pin: PB1
+dir_pin: PB0
+enable_pin: !PD6
+step_distance: .002
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: PD5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PA7
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: PD2
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PA6
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: PB4
+
+[mcu]
+serial: /dev/ttyUSB0
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100

config/generic-mini-rambo.cfg

@@ -0,0 +1,109 @@
+# This file contains common pin mappings for Mini-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: .005
+endstop_pin: ^PB6
+#endstop_pin: ^PC7
+position_endstop: 0
+position_max: 250
+
+[stepper_y]
+step_pin: PC1
+dir_pin: !PL0
+enable_pin: !PA6
+step_distance: .005
+endstop_pin: ^PB5
+#endstop_pin: ^PA2
+position_endstop: 0
+position_max: 210
+
+[stepper_z]
+step_pin: PC2
+dir_pin: PL2
+enable_pin: !PA5
+step_distance: .0025
+endstop_pin: ^PB4
+#endstop_pin: ^PA1
+position_endstop: 0.5
+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: PE5
+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: PG5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF2
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: PH5
+
+#[heater_fan nozzle_cooling_fan]
+#pin: PH3
+
+[mcu]
+serial: /dev/ttyACM0
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100
+
+[output_pin stepper_xy_current]
+pin: PL3
+pwm: True
+scale: 2.0
+cycle_time: .002
+hardware_pwm: True
+static_value: 1.3
+
+[output_pin stepper_z_current]
+pin: PL4
+pwm: True
+scale: 2.0
+cycle_time: .002
+hardware_pwm: True
+static_value: 1.3
+
+[output_pin stepper_e_current]
+pin: PL5
+pwm: True
+scale: 2.0
+cycle_time: .002
+hardware_pwm: True
+static_value: 1.25
+
+[static_digital_output stepper_config]
+pins:
+    PG1, PG0,
+    PK7, PG2,
+    PK6, PK5,
+    PK3, PK4
+
+[static_digital_output yellow_led]
+pins: !PB7

config/generic-printrboard.cfg

@@ -0,0 +1,76 @@
+# This file contains common pin mappings for Printrboard boards (rev B
+# through D). To use this config the firmware should be compiled for
+# the AVR at90usb1286.
+
+# Note that the "make flash" command is unlikely to work on the
+# Printrboard. See the RepRap Printrboard wiki page for instructions
+# on flashing.
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: PA0
+dir_pin: !PA1
+enable_pin: !PE7
+step_distance: .0125
+endstop_pin: ^PE3
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_y]
+step_pin: PA2
+dir_pin: PA3
+enable_pin: !PE6
+step_distance: .0125
+endstop_pin: ^PB0
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: PA4
+dir_pin: !PA5
+enable_pin: !PC7
+step_distance: .0025
+endstop_pin: ^PE4
+position_endstop: 0.5
+position_max: 200
+
+[extruder]
+step_pin: PA6
+dir_pin: PA7
+enable_pin: !PC3
+step_distance: .002
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: PC5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF1
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: PC4
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF0
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: PC6
+
+[mcu]
+serial: /dev/ttyACM0
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100

config/generic-rambo.cfg

@@ -0,0 +1,126 @@
+# 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
+#endstop_pin: ^PA2
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_y]
+step_pin: PC1
+dir_pin: !PL0
+enable_pin: !PA6
+step_distance: .0125
+endstop_pin: ^PB5
+#endstop_pin: ^PA1
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: PC2
+dir_pin: PL2
+enable_pin: !PA5
+step_distance: .0025
+endstop_pin: ^PB4
+#endstop_pin: ^PC7
+position_endstop: 0.5
+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
+
+#[extruder1]
+#step_pin: PC4
+#dir_pin: PL7
+#enable_pin: !PA3
+#heater_pin: PH4
+#sensor_pin: PF1
+#...
+
+[heater_bed]
+heater_pin: PE5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF2
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: PH5
+
+#[heater_fan nozzle_cooling_fan]
+#pin: PH3
+
+[mcu]
+serial: /dev/ttyACM0
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100
+
+[ad5206 stepper_digipot]
+enable_pin: PD7
+# Scale the config so that the channel value can be specified in amps.
+# (For Rambo v1.0d boards, use 1.56 instead.)
+scale: 2.08
+# Channel 1 is E0, 2 is E1, 3 is unused, 4 is Z, 5 is X, 6 is Y
+channel_1: 1.34
+channel_2: 1.0
+channel_4: 1.1
+channel_5: 1.1
+channel_6: 1.1
+
+# Enable 16 micro-steps on steppers X, Y, Z, E0, E1
+[static_digital_output stepper_config]
+pins:
+    PG1, PG0,
+    PK7, PG2,
+    PK6, PK5,
+    PK3, PK4,
+    PK1, PK2
+
+[static_digital_output yellow_led]
+pins: !PB7
+
+# "RepRapDiscount 2004 Smart Controller" type displays
+#[display]
+#lcd_type: hd44780
+#rs_pin: PG4
+#e_pin: PG3
+#d4_pin: PJ2
+#d5_pin: PJ3
+#d6_pin: PJ7
+#d7_pin: PJ4
+
+# "RepRapDiscount 128x64 Full Graphic Smart Controller" type displays
+#[display]
+#lcd_type: st7920
+#cs_pin: PG4
+#sclk_pin: PJ2
+#sid_pin: PG3

config/generic-ramps.cfg

@@ -0,0 +1,101 @@
+# 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
+#endstop_pin: ^ar2
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_y]
+step_pin: ar60
+dir_pin: !ar61
+enable_pin: !ar56
+step_distance: .0125
+endstop_pin: ^ar14
+#endstop_pin: ^ar15
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: ar46
+dir_pin: ar48
+enable_pin: !ar62
+step_distance: .0025
+endstop_pin: ^ar18
+#endstop_pin: ^ar19
+position_endstop: 0.5
+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
+
+#[extruder1]
+#step_pin: ar36
+#dir_pin: ar34
+#enable_pin: !ar30
+#heater_pin: ar9
+#sensor_pin: analog15
+#...
+
+[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
+
+# "RepRapDiscount 2004 Smart Controller" type displays
+#[display]
+#lcd_type: hd44780
+#rs_pin: ar16
+#e_pin: ar17
+#d4_pin: ar23
+#d5_pin: ar25
+#d6_pin: ar27
+#d7_pin: ar29
+
+# "RepRapDiscount 128x64 Full Graphic Smart Controller" type displays
+#[display]
+#lcd_type: st7920
+#cs_pin: ar16
+#sclk_pin: ar23
+#sid_pin: ar17

config/generic-replicape.cfg

@@ -0,0 +1,134 @@
+# This file contains an example configuration for the Replicape rev B3
+# board. To use this config, one must compile and install the
+# micro-controller code for the "Beaglebone PRU", and then compile and
+# install the micro-controller code a second time for a "Linux
+# process".
+
+# NOTE: Klipper does not alter the input/output state of the
+# Beaglebone pins and it does not control their pull-up resistors.
+# Typically the correct settings are automatically applied when the
+# Beaglebone detects the Replicape board, but if changes are needed
+# they must be specified in a "device tree overlay" or via the
+# config-pin program.
+
+# See the example.cfg file for a description of available parameters.
+
+[mcu]
+serial: /dev/rpmsg_pru30
+pin_map: beaglebone
+
+[mcu host]
+serial: /tmp/klipper_host_mcu
+
+# The "replicape" config section adds "replicape:stepper_x_enable"
+# virtual stepper enable pins (for steppers x, y, z, e, and h) and
+# "replicape:power_x" PWM output pins (for hotbed, e, h, fan0, fan1,
+# fan2, and fan3) that may then be used elsewhere in the config file.
+[replicape]
+revision: B3
+#   The replicape hardware revision. Currently only revision "B3" is
+#   supported. This parameter must be provided.
+#enable_pin: !P9_41
+#   The replicape global enable pin. The default is !P9_41.
+host_mcu: host
+#   The name of the mcu config section that communicates with the
+#   Klipper "linux process" mcu instance. This parameter must be
+#   provided.
+#standstill_power_down: False
+#   This parameter controls the CFG6_ENN line on all stepper
+#   motors. True sets the enable lines to "open". The default is
+#   False.
+#servo0_enable: False
+#   This parameter controls whether end_stop_X_2 is used for endstops
+#   (via P9_11) or for servo_0 (via P9_14). The default is False.
+#servo1_enable: False
+#   This parameter controls whether end_stop_Y_2 is used for endstops
+#   (via P9_28) or for servo_1 (via P9_16). The default is False.
+stepper_x_microstep_mode: spread16
+#   This parameter controls the CFG1 and CFG2 pins of the given
+#   stepper motor driver. Available options are: disable, 1, 2,
+#   spread2, 4, 16, spread4, spread16, stealth4, and stealth16. The
+#   default is disable.
+stepper_x_current: 0.5
+#   The configured maximum current (in Amps) of the stepper motor
+#   driver. This parameter must be provided if the stepper is not in a
+#   disable mode.
+#stepper_x_chopper_off_time_high: False
+#   This parameter controls the CFG0 pin of the stepper motor driver
+#   (True sets CFG0 high, False sets it low). The default is False.
+#stepper_x_chopper_hysteresis_high: False
+#   This parameter controls the CFG4 pin of the stepper motor driver
+#   (True sets CFG4 high, False sets it low). The default is False.
+#stepper_x_chopper_blank_time_high: True
+#   This parameter controls the CFG5 pin of the stepper motor driver
+#   (True sets CFG5 high, False sets it low). The default is True.
+stepper_y_microstep_mode: spread16
+stepper_y_current: 0.5
+stepper_z_microstep_mode: spread16
+stepper_z_current: 0.5
+stepper_e_microstep_mode: 16
+stepper_e_current: 0.5
+
+[stepper_x]
+step_pin: P8_17
+dir_pin: P8_26
+enable_pin: replicape:stepper_x_enable
+step_distance: .0125
+endstop_pin: ^P9_25
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_y]
+step_pin: P8_12
+dir_pin: P8_19
+enable_pin: replicape:stepper_y_enable
+step_distance: .0125
+endstop_pin: ^P9_23
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: P8_13
+dir_pin: P8_14
+enable_pin: replicape:stepper_z_enable
+step_distance: .0025
+endstop_pin: ^P9_13
+position_endstop: 0
+position_max: 200
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 25
+max_z_accel: 30
+
+[extruder]
+step_pin: P9_12
+dir_pin: P8_15
+enable_pin: replicape:stepper_e_enable
+step_distance: .002
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: replicape:power_e
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: host:analog4
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: replicape:power_hotbed
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: host:analog6
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: replicape:power_fan0

config/printer-anet-a8-2017.cfg

@@ -0,0 +1,79 @@
+# This file contains common pin mappings for Anet A8 printer from 2016
+# and 2017. To use this config, the firmware should be compiled for
+# the AVR atmega1284p.
+
+# Note that the "make flash" command does not work with Anet boards -
+# the boards are typically flashed with this command:
+#  avrdude -p atmega1284p -c arduino -b 57600 -P /dev/ttyUSB0 -U out/klipper.elf.hex
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: PD7
+dir_pin: PC5
+enable_pin: !PD6
+step_distance: .01
+endstop_pin: ^!PC2
+position_endstop: -30
+position_max: 220
+position_min: -30
+homing_speed: 50
+
+[stepper_y]
+step_pin: PC6
+dir_pin: PC7
+enable_pin: !PD6
+step_distance: .01
+endstop_pin: ^!PC3
+position_endstop: -8
+position_min: -8
+position_max: 220
+homing_speed: 50
+
+[stepper_z]
+step_pin: PB3
+dir_pin: !PB2
+enable_pin: !PA5
+step_distance: .0025
+endstop_pin: ^!PC4
+position_endstop: 0.5
+position_max: 240
+homing_speed: 20
+
+[extruder]
+step_pin: PB1
+dir_pin: PB0
+enable_pin: !PD6
+step_distance: .0105
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: PD5
+sensor_type: ATC Semitec 104GT-2
+sensor_pin: PA7
+control: pid
+pid_Kp: 2.151492
+pid_Ki: 0.633897
+pid_Kd: 230.042965
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: PD4
+sensor_type: ATC Semitec 104GT-2
+sensor_pin: PA6
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: PB4
+
+[mcu]
+serial: /dev/ttyUSB0
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 1000
+max_z_velocity: 20
+max_z_accel: 100

config/printer-anycubic-i3-mega-2017.cfg

@@ -0,0 +1,93 @@
+# This file contains pin mappings for the Anycubic i3 Mega with
+# Ultrabase from 2017. (This config may work on an Anycubic i3 Mega v1
+# prior to the Ultrabase if you comment out the definition of the
+# endstop_pin in the stepper_z1 section.) 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: ar54
+dir_pin: !ar55
+enable_pin: !ar38
+step_distance: .0125
+endstop_pin: ^!ar3
+position_min: -5
+position_endstop: -5
+position_max: 210
+homing_speed: 30.0
+
+[stepper_y]
+step_pin: ar60
+dir_pin: ar61
+enable_pin: !ar56
+step_distance: .0125
+endstop_pin: ^!ar42
+position_endstop: 0
+position_max: 210
+homing_speed: 30.0
+
+[stepper_z]
+step_pin: ar46
+dir_pin: ar48
+enable_pin: !ar62
+step_distance: .0025
+endstop_pin: ^!ar18
+position_endstop: 0.0
+position_max: 205
+homing_speed: 5.0
+
+[stepper_z1]
+step_pin: ar36
+dir_pin: ar34
+enable_pin: !ar30
+step_distance: .0025
+endstop_pin: ^!ar43
+
+[extruder]
+step_pin: ar26
+dir_pin: ar28
+enable_pin: !ar24
+step_distance: .010799
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: ar10
+sensor_type: ATC Semitec 104GT-2
+sensor_pin: analog13
+control: pid
+pid_Kp: 15.717
+pid_Ki: 0.569
+pid_Kd: 108.451
+min_temp: 0
+max_temp: 245
+
+[heater_fan extruder_fan]
+pin: ar44
+
+[heater_bed]
+heater_pin: ar8
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog14
+control: pid
+pid_Kp: 74.883
+pid_Ki: 1.809
+pid_Kd: 775.038
+min_temp: 0
+max_temp: 110
+
+[fan]
+pin: ar9
+
+[mcu]
+serial: /dev/ttyUSB0
+pin_map: arduino
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 10
+max_z_accel: 60
+
+[heater_fan stepstick_fan]
+pin: ar7

config/printer-creality-cr10-2017.cfg

@@ -0,0 +1,88 @@
+# This file contains common pin mappings for the 2017 Creality
+# CR-10. To use this config, the firmware should be compiled for the
+# AVR atmega1284p.
+
+# Note, a number of Melzi boards are shipped without a bootloader. In
+# that case, an external programmer will be needed to flash a
+# bootloader to the board (for example, see
+# http://www.instructables.com/id/Flashing-a-Bootloader-to-the-CR-10/
+# ). Once that is done, one should be able to use the standard "make
+# flash" command to flash Klipper.
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: PD7
+dir_pin: !PC5
+enable_pin: !PD6
+step_distance: .0125
+endstop_pin: ^PC2
+position_endstop: 0
+position_max: 300
+homing_speed: 50
+
+[stepper_y]
+step_pin: PC6
+dir_pin: !PC7
+enable_pin: !PD6
+step_distance: .0125
+endstop_pin: ^PC3
+position_endstop: 0
+position_max: 300
+homing_speed: 50
+
+[stepper_z]
+step_pin: PB3
+dir_pin: PB2
+enable_pin: !PA5
+step_distance: .0025
+endstop_pin: ^PC4
+position_endstop: 0.0
+position_max: 400
+
+[extruder]
+step_pin: PB1
+dir_pin: !PB0
+enable_pin: !PD6
+step_distance: 0.010526
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: PD5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PA7
+control: pid
+pid_Kp: 22.57
+pid_Ki: 1.72
+pid_Kd: 73.96
+min_temp: 0
+max_temp: 250
+
+[heater_bed]
+heater_pin: PD4
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PA6
+control: pid
+pid_Kp: 426.68
+pid_Ki: 78.92
+pid_Kd: 576.71
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: PB4
+
+[mcu]
+serial: /dev/ttyUSB0
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100
+
+[display]
+lcd_type: st7920
+cs_pin: PA3
+sclk_pin: PA1
+sid_pin: PC1

config/printer-creality-cr10s-2017.cfg

@@ -0,0 +1,75 @@
+# This file contains pin mappings for the 2017 Creality CR-10S. 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: ar54
+dir_pin: ar55
+enable_pin: !ar38
+step_distance: .0125
+endstop_pin: ^ar3
+position_endstop: 0
+position_max: 300
+homing_speed: 50
+
+[stepper_y]
+step_pin: ar60
+dir_pin: ar61
+enable_pin: !ar56
+step_distance: .0125
+endstop_pin: ^ar14
+position_endstop: 0
+position_max: 300
+homing_speed: 50
+
+[stepper_z]
+step_pin: ar46
+dir_pin: !ar48
+enable_pin: !ar62
+step_distance: .0025
+endstop_pin: ^ar18
+position_endstop: 0.5
+position_max: 200
+
+[extruder]
+step_pin: ar26
+dir_pin: ar28
+enable_pin: !ar24
+step_distance: .010526
+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: pid
+pid_Kp: 690.34
+pid_Ki: 111.47
+pid_Kd: 1068.83
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: ar9
+
+[mcu]
+serial: /dev/ttyUSB0
+pin_map: arduino
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100

config/printer-lulzbot-taz6-2017.cfg

@@ -0,0 +1,116 @@
+# This file contains pin mappings for the Lulzbot TAZ 6 circa 2017. 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: .010000
+endstop_pin: ^PB6
+position_endstop: -20
+position_min: -20
+position_max: 300
+homing_speed: 50
+
+[stepper_y]
+step_pin: PC1
+dir_pin: !PL0
+enable_pin: !PA6
+step_distance: .010000
+endstop_pin: ^PA1
+position_endstop: 306
+position_min: -20
+position_max: 306
+homing_speed: 50
+
+[stepper_z]
+step_pin: PC2
+dir_pin: PL2
+enable_pin: !PA5
+step_distance: 0.000625
+endstop_pin: ^!PB4
+position_endstop: -0.7
+position_min: -1.5
+position_max: 270
+homing_speed: 1
+
+[extruder]
+step_pin: PC3
+dir_pin: !PL6
+enable_pin: !PA4
+step_distance: 0.001182
+nozzle_diameter: 0.400
+filament_diameter: 2.920
+heater_pin: PH6
+sensor_type: ATC Semitec 104GT-2
+sensor_pin: PF0
+control: pid
+pid_Kp: 28.79
+pid_Ki: 1.91
+pid_Kd: 108.51
+min_temp: 0
+max_temp: 300
+min_extrude_temp: 140
+
+#[extruder1]
+#step_pin: PC4
+#dir_pin: PL7
+#enable_pin: !PA3
+#heater_pin: PH4
+#sensor_pin: PF1
+#...
+
+[heater_bed]
+heater_pin: PE5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF2
+control: watermark
+min_temp: 0
+max_temp: 130
+
+[fan]
+pin: PH5
+
+[heater_fan nozzle_cooling_fan]
+pin: PH3
+
+[mcu]
+serial: /dev/ttyACM0
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 2
+max_z_accel: 10
+
+[ad5206 stepper_digipot]
+enable_pin: PD7
+scale: 2.08
+# Channel 1 is E0, 2 is E1, 3 is unused, 4 is Z, 5 is X, 6 is Y
+channel_1: 1.34
+channel_2: 1.0
+channel_4: 1.1
+channel_5: 1.1
+channel_6: 1.1
+
+# Enable 16 micro-steps on steppers X, Y, Z, E0, E1
+[static_digital_output stepper_config]
+pins:
+    PG1, PG0,
+    PK7, PG2,
+    PK6, PK5,
+    PK3, PK4,
+    PK1, PK2
+
+[static_digital_output yellow_led]
+pins: !PB7
+
+[display]
+lcd_type: st7920
+cs_pin: PG4
+sclk_pin: PJ2
+sid_pin: PG3

config/printer-makergear-m2-2012.cfg

@@ -9,12 +9,11 @@ dir_pin: !PL1
 enable_pin: !PA7
 step_distance: .0225
 endstop_pin: ^!PB6
-homing_speed: 50.0
-homing_stepper_phases: 32
-homing_endstop_accuracy: .200
-position_min: -0.25
 position_endstop: 0.0
 position_max: 200
+homing_speed: 50
+homing_stepper_phases: 32
+homing_endstop_accuracy: .200
 
 [stepper_y]
 step_pin: PC1
@@ -22,12 +21,11 @@ dir_pin: PL0
 enable_pin: !PA6
 step_distance: .0225
 endstop_pin: ^!PB5
-homing_speed: 50.0
-homing_stepper_phases: 32
-homing_endstop_accuracy: .200
-position_min: -0.25
 position_endstop: 0.0
 position_max: 250
+homing_speed: 50
+homing_stepper_phases: 32
+homing_endstop_accuracy: .200
 
 [stepper_z]
 step_pin: PC2
@@ -35,25 +33,24 @@ dir_pin: !PL2
 enable_pin: !PA5
 step_distance: .005
 endstop_pin: ^!PB4
-homing_speed: 4.0
-homing_retract_dist: 2.0
-homing_stepper_phases: 32
-homing_endstop_accuracy: .050
 position_min: 0.1
 position_endstop: 0.7
 position_max: 200
+homing_retract_dist: 2.0
+homing_stepper_phases: 32
+homing_endstop_accuracy: .070
 
 [extruder]
 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
@@ -63,44 +60,49 @@ 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
+
+[heater_fan nozzle_fan]
+pin: PH3
+max_power: 0.61
+cycle_time: .000030
+hardware_pwm: True
 
 [mcu]
 serial: /dev/ttyACM0
-baud: 250000
-custom:
-  # Nozzle fan
-  set_pwm_out pin=PH3 cycle_ticks=1 value=155
-  # 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: 500
 max_accel: 3000
-max_z_velocity: 250
+max_z_velocity: 25
 max_z_accel: 30
-motor_off_time: 600
+
+[ad5206 stepper_digipot]
+enable_pin: PD7
+# Scale the config so that the channel value can be specified in amps
+scale: 1.56
+# Channel 1 is E0, 2 is E1, 3 is unused, 4 is Z, 5 is X, 6 is Y
+channel_1: 1.0
+channel_2: 0.75
+channel_4: 0.82
+channel_5: 0.82
+channel_6: 0.82
+
+# Enable 8 micro-steps on steppers X, Y, Z, E0
+[static_digital_output stepper_config]
+pins:
+    PG1, PG0,
+    PK7, PG2,
+    PK6, PK5,
+    PK3, PK4
+
+[static_digital_output yellow_led]
+pins: !PB7

config/printer-seemecnc-rostock-max-v2-2015.cfg

@@ -0,0 +1,94 @@
+# This file constains the pin mappings for the SeeMeCNC Rostock Max
+# (version 2) delta printer from 2015. 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_a]
+step_pin: PC0
+dir_pin: !PL1
+enable_pin: !PA7
+step_distance: .0125
+endstop_pin: ^PA2
+homing_speed: 50
+position_endstop: 380
+arm_length: 290.800
+
+[stepper_b]
+step_pin: PC1
+dir_pin: PL0
+enable_pin: !PA6
+step_distance: .0125
+endstop_pin: ^PA1
+
+[stepper_c]
+step_pin: PC2
+dir_pin: !PL2
+enable_pin: !PA5
+step_distance: .0125
+endstop_pin: ^PC7
+
+[extruder]
+step_pin: PC3
+dir_pin: !PL6
+enable_pin: !PA4
+step_distance: .010793
+nozzle_diameter: 0.500
+filament_diameter: 1.750
+heater_pin: PH6
+sensor_type: ATC Semitec 104GT-2
+sensor_pin: PF0
+control: pid
+pid_Kp: 20.9700
+pid_Ki: 1.3400
+pid_Kd: 80.5600
+min_temp: 0
+max_temp: 300
+
+[heater_bed]
+heater_pin: PE5
+sensor_type: ATC Semitec 104GT-2
+sensor_pin: PF2
+control: pid
+pid_Kp: 46.510
+pid_Ki: 1.040
+pid_Kd: 500.000
+min_temp: 0
+max_temp: 300
+
+[fan]
+pin: PH5
+
+[heater_fan nozzle_cooling_fan]
+pin: PH4
+heater: extruder
+
+[mcu]
+serial: /dev/ttyACM0
+
+[printer]
+kinematics: delta
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 150
+delta_radius: 174.75
+
+[ad5206 stepper_digipot]
+enable_pin: PD7
+scale: 2.08
+channel_1: 1.34
+channel_2: 1.0
+channel_4: 1.1
+channel_5: 1.1
+channel_6: 1.1
+
+[static_digital_output stepper_config]
+pins:
+    PG1, PG0,
+    PK7, PG2,
+    PK6, PK5,
+    PK3, PK4,
+    PK1, PK2
+
+[static_digital_output yellow_led]
+pins: !PB7

config/printer-tronxy-x5s-2017.cfg

@@ -0,0 +1,89 @@
+# This file contains pin mappings for the Tronxy X5S (circa 2017). To
+# use this config, the firmware should be compiled for the AVR
+# atmega1284p.
+
+# Note, a number of Melzi boards are shipped without a bootloader. In
+# that case, an external programmer will be needed to flash a
+# bootloader to the board (for example, see
+# http://www.instructables.com/id/Flashing-a-Bootloader-to-the-CR-10/
+# ). Once that is done, one should be able to use the standard "make
+# flash" command to flash Klipper.
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: PD7
+dir_pin: !PC5
+enable_pin: !PD6
+step_distance: .0125
+endstop_pin: ^!PC2
+position_endstop: 0
+position_max: 330
+homing_speed: 50
+
+[stepper_y]
+step_pin: PC6
+dir_pin: !PC7
+enable_pin: !PD6
+step_distance: .0125
+endstop_pin: ^!PC3
+position_endstop: 0
+position_max: 310
+homing_speed: 50
+
+[stepper_z]
+step_pin: PB3
+dir_pin: PB2
+enable_pin: !PD6
+step_distance: .0025
+endstop_pin: ^!PC4
+position_endstop: 0.5
+position_max: 400
+
+[extruder]
+step_pin: PB1
+dir_pin: PB0
+enable_pin: !PD6
+step_distance: .0111
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: PD5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PA7
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 275
+
+[heater_bed]
+heater_pin: PD4
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PA6
+control: watermark
+min_temp: 0
+max_temp: 150
+
+[fan]
+pin: PB4
+
+[mcu]
+serial: /dev/ttyUSB0
+
+[printer]
+kinematics: corexy
+max_velocity: 300
+max_accel: 1000
+max_z_velocity: 20
+max_z_accel: 100
+
+[display]
+lcd_type: st7920
+cs_pin: PA1
+sclk_pin: PC0
+sid_pin: PA3
+
+# buttons are:
+# PD2, PD3: encoder
+# PA5: click

config/printer-wanhao-duplicator-i3-plus-2017.cfg

@@ -0,0 +1,78 @@
+# This file contains pin mappings for the Wanhao Duplicator i3 Plus
+# (circa 2017).  To use this config, the firmware should be compiled
+# for the AVR atmega2560.
+# Pin numbers and other parameters were extracted from the
+# official Marlin source available at:
+# https://github.com/garychen99/Duplicator-i3-plus
+
+# See the example.cfg file for a description of available parameters.
+
+[stepper_x]
+step_pin: PF7
+dir_pin: !PK0
+enable_pin: !PF6
+step_distance: .0125
+endstop_pin: ^!PF0
+position_endstop: 0
+position_max: 200
+homing_speed: 30.0
+
+[stepper_y]
+step_pin: PK2
+dir_pin: !PK3
+enable_pin: !PK1
+step_distance: .0125
+endstop_pin: ^!PA2
+position_endstop: 0
+position_max: 200
+homing_speed: 30.0
+
+[stepper_z]
+step_pin: PK5
+dir_pin: PK7
+enable_pin: !PK4
+step_distance: .0025
+endstop_pin: ^!PA1
+position_endstop: 0.5
+position_max: 180
+
+[extruder]
+step_pin: PF4
+dir_pin: PF5
+enable_pin: !PF3
+step_distance: 0.010417
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: PG5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PF1
+control: pid
+pid_Kp: 30.850721
+pid_Ki: .208175
+pid_Kd: 192.298728
+min_temp: 0
+max_temp: 260
+
+[heater_bed]
+heater_pin: PE5
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: PK6
+control: pid
+pid_Kp: 64.095903
+pid_Ki: 1.649830
+pid_Kd: 622.531455
+min_temp: 0
+max_temp: 110
+
+[fan]
+pin: PE3
+
+[mcu]
+serial: /dev/ttyUSB0
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 800
+max_z_velocity: 5
+max_z_accel: 100

config/printer-wanhao-duplicator-i3-v2.1-2017.cfg

@@ -0,0 +1,159 @@
+# This file contains pin mappings and other appropriate default parameters
+# for a Wanhao Duplicator i3 v2.1 and its clones
+# (Monoprice Maker Select, Cocoon Create, etc.)
+# See the files example.cfg and example-extras.cfg for a description of available parameters.
+#
+# This will probably work on older revisions (v1.0, v2.0) of the printer
+# but is untested on those versions.
+#
+# For best results with klipper and the Wanhao Duplicator i3, follow these
+# guidelines:
+#
+# - Flash a bootloader to the Melzi board in the printer
+#   See http://www.instructables.com/id/Using-an-Arduino-to-Flash-the-Melzi-Board-Wanhao-I/
+#
+# - Make sure the auto-reset jumper is *enabled* on the Melzi board
+#   (See step 1 in the bootloader tutorial above)
+#
+# - Locate the USB serial port for your printer in /dev/serial/by-id/ format.
+#   See https://github.com/KevinOConnor/klipper/blob/master/docs/FAQ.md#wheres-my-serial-port
+#   It will be something like:
+#   /dev/serial/by-id/usb-FTDI_FT232R_USB_UART_ABCD1234-if00-port0
+#
+# - Configure klipper to compile firmware for the AVR atmega1284p
+#
+# - At this point, "make flash FLASH_DEVICE=..." should successfully
+#   flash your printer board. Use the /dev/serial/by-id/ format for
+#   FLASH_DEVICE to ensure consistent results.
+#   See https://github.com/KevinOConnor/klipper/blob/master/docs/FAQ.md#the-make-flash-command-doesnt-work
+#   if you have problems.
+#
+# - Copy this sample file you are currently reading to ~/printer.cfg,
+#   and customize the following parameters:
+#   * [extruder] > step_distance
+#
+#     This is the inverse of "E steps" (extruder steps per mm) from the stock
+#     Wanhao Repetier-based firmware.
+#     (See https://3dprinterwiki.info/extruder-steps/ )
+#
+#     For example, if your E-steps are set to 107.0 steps per mm,
+#     then step_distance should be (1 / 107.0) ~= .009346
+#
+#   * [extruder] > PID parameters (pid_Kp, pid_Ki, pid_Kd)
+#   * [heater_bed] > PID parameters (pid_Kp, pid_Ki, pid_Kd)
+#
+#     PID values from stock Wanhao firmware (Repetier) do not
+#     translate directly to klipper. You will need to run klipper's
+#     PID autotune function for the extruder and bed. After getting the
+#     klipper firmware up and running, run the PID_CALIBRATE procedures
+#     by sending these commands via octoprint terminal (one per autotune):
+#
+#        extruder:   PID_CALIBRATE HEATER=extruder TARGET=<temp>
+#        heated bed: PID_CALIBRATE HEATER=heater_bed TARGET=<temp>
+#
+#     After the autotune process completes, PID parameter results
+#     can be found in the Octoprint terminal tab (if you're quick)
+#     or in /tmp/klippy.log.
+#
+#     Enter the PID parameters into the appropriate sections of ~/printer.cfg .
+#
+#   * [extruder] > max_temp
+#   * [heater_bed] > max_temp
+#
+#     The max temps included in this printer config are limited to 230 for extruder
+#     and 70 for heated bed. If your printer has been modified to handle higher temps
+#     (like an upgraded hot end or a separate MOSFET for your heated bed), you may
+#     want to increase these values.
+#
+#   * [mcu] > serial
+#
+#     Enter the USB serial port of the printer in /dev/serial/by-id/ format
+#     for best results.
+#
+# - Power cycle the Wanhao Duplicator i3
+#
+# - Issue the command "RESTART" via the Octoprint terminal tab (similar to
+#   how you would send a manual gcode command, but send the word RESTART).
+#   This tells klipper to reload its config file and do an internal reset.
+#   You should then see a status screen appear on the printer's LCD.
+#
+# - Be sure to follow these instructions before attempting any prints:
+#   https://github.com/KevinOConnor/klipper/blob/master/docs/Config_checks.md
+
+[stepper_x]
+step_pin: PD7
+dir_pin: PC5
+enable_pin: !PD6
+step_distance: .0125
+endstop_pin: ^!PC2
+position_endstop: 0
+position_max: 200
+homing_speed: 40
+
+[stepper_y]
+step_pin: PC6
+dir_pin: PC7
+enable_pin: !PD6
+step_distance: .0125
+endstop_pin: ^!PC3
+position_endstop: 0
+position_max: 200
+homing_speed: 40
+
+[stepper_z]
+step_pin: PB3
+dir_pin: !PB2
+enable_pin: !PA5
+step_distance: 0.0025
+endstop_pin: ^!PC4
+position_endstop: 0.5
+position_max: 180
+homing_speed: 2
+
+[extruder]
+step_pin: PB1
+dir_pin: !PB0
+enable_pin: !PD6
+step_distance: .009346
+nozzle_diameter: 0.400
+filament_diameter: 1.750
+heater_pin: PD5
+sensor_type: NTC 100K beta 3950
+sensor_pin: PA7
+control: pid
+pid_Kp: 18.214030
+pid_Ki: 0.616380
+pid_Kd: 134.556146
+min_temp: 0
+max_temp: 230
+
+[heater_bed]
+heater_pin: PD4
+sensor_type: NTC 100K beta 3950
+sensor_pin: PA6
+control: pid
+pid_Kp: 71.321
+pid_Ki: 1.989
+pid_Kd: 639.210
+min_temp: 0
+max_temp: 70
+
+[fan]
+pin: PB4
+
+[mcu]
+serial: /dev/ttyUSB0
+restart_method: command
+
+[printer]
+kinematics: cartesian
+max_velocity: 200
+max_accel: 1000
+max_z_velocity: 2
+max_z_accel: 100
+
+[display]
+lcd_type: st7920
+cs_pin: PC1
+sclk_pin: PD3
+sid_pin: PC0

config/sample-bltouch.cfg

@@ -0,0 +1,56 @@
+# This file provides example config file settings for the BLTouch
+# automatic bed leveling sensor. This file is just a "snippet" of
+# sections specific to the BLTouch - it must be added to a config file
+# containing the configuration of the rest of the printer.
+
+# Be sure to review and update this config with the appropriate pins
+# and coordinates for your printer.
+
+# See the "example.cfg" and "example-extras.cfg" files for a
+# description of config parameters.
+
+# Define the BLTouch servo
+[servo bltouch]
+pin: ar32
+maximum_servo_angle: 180
+minimum_pulse_width: 0.0006
+maximum_pulse_width: 0.0024
+
+# Define a probe using the BLTouch
+[probe]
+pin: ar30
+activate_gcode:
+    SET_SERVO SERVO=bltouch ANGLE=10
+    SET_SERVO SERVO=bltouch ANGLE=60
+    G4 P200
+deactivate_gcode:
+    SET_SERVO SERVO=bltouch ANGLE=90
+
+# Example bed_tilt config section
+[bed_tilt]
+#x_adjust:
+#y_adjust:
+points:
+    100,100
+    10,10
+    10,100
+    10,190
+    100,10
+    100,190
+    190,10
+    190,100
+    190,190
+probe_z_offset: 2.345
+
+# If the BLTouch is used to home the Z axis, then define a
+# homing_override section, use probe:z_virtual_endstop as the
+# endstop_pin in the stepper_z section, and set the endstop_position
+# in the stepper_z section to match the probe's probe_z_offset.
+#[homing_override]
+#set_position_z: 5
+#gcode:
+#    ; G90   ; Uncomment these 2 lines to blindly lift the Z 2mm at start
+#    ; G1 Z7 F600
+#    G28 X0 Y0
+#    G1 X100 Y100 F3600
+#    G28 Z0

docs/CONTRIBUTING.md

@@ -0,0 +1,38 @@
+# Contributing to Klipper
+
+Thank you for contributing to Klipper! Please take a moment to read
+this document.
+
+## Creating a new issue
+
+Please see the [contact page](Contact.md) for information on creating
+an issue. In particular, **we need the klippy.log file** attached to
+bug reports. Also, be sure to read the [FAQ](FAQ.md) to see if a
+similar issue has already been raised.
+
+## Submitting a pull request
+
+Contributions of Code and documentation are managed through github
+pull requests.  Each commit should have a commit message formatted
+similar to the following:
+
+```
+module: Capitalized, short (50 chars or less) summary
+
+More detailed explanatory text, if necessary.  Wrap it to about 75
+characters or so.  In some contexts, the first line is treated as the
+subject of an email and the rest of the text as the body.  The blank
+line separating the summary from the body is critical (unless you omit
+the body entirely); tools like rebase can get confused if you run the
+two together.
+
+Further paragraphs come after blank lines..
+
+Signed-off-by: My Name <myemail@example.org>
+```
+
+It is important to have a "Signed-off-by" line on each commit - it
+certifies that you agree to the
+[developer certificate of origin](developer-certificate-of-origin). It
+must contain your real name (sorry, no pseudonyms or anonymous
+contributions) and contain a current email address.

docs/Code_Overview.md

@@ -8,16 +8,17 @@ The **src/** directory contains the C source for the micro-controller
 code. The **src/avr/** directory contains specific code for Atmel
 ATmega micro-controllers. The **src/sam3x8e/** directory contains code
 specific to the Arduino Due style ARM micro-controllers. The
-**src/simulator/** contains code stubs that allow the micro-controller
-to be test compiled on other architectures. The **src/generic/**
-directory contains helper code that may be useful across different
-host architectures. The build arranges for includes of
-"board/somefile.h" to first look in the current architecture directory
-(eg, src/avr/somefile.h) and then in the generic directory (eg,
-src/generic/somefile.h).
+**src/pru/** directory contains code specific to the Beaglebone's
+on-board PRU micro-controller. The **src/simulator/** contains code
+stubs that allow the micro-controller to be test compiled on other
+architectures. The **src/generic/** directory contains helper code
+that may be useful across different host architectures. The build
+arranges for includes of "board/somefile.h" to first look in the
+current architecture directory (eg, src/avr/somefile.h) and then in
+the generic directory (eg, 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.
@@ -28,6 +29,8 @@ files.
 The **scripts/** directory contains build-time scripts useful for
 compiling the micro-controller code.
 
+The **test/** directory contains automated test cases.
+
 During compilation, the build may create an **out/** directory. This
 contains temporary build time objects. The final micro-controller
 object that is built is **out/klipper.elf.hex** on AVR and
@@ -43,10 +46,12 @@ all functions that have been tagged with the DECL_INIT() macro. It
 then goes on to repeatedly run all functions tagged with the
 DECL_TASK() macro.
 
-One of the main task functions is command_task() located in
-**src/command.c**. This function processes incoming serial commands
-and runs the associated command function for them. Command functions
-are declared using the DECL_COMMAND() macro.
+One of the main task functions is command_dispatch() located in
+**src/command.c**. This function is called from the board specific
+input/output code (eg, **src/avr/serial.c**) and it runs the command
+functions associated with the commands found in the input
+stream. Command functions are declared using the DECL_COMMAND() macro
+(see the [protocol](Protocol.md) document for more information).
 
 Task, init, and command functions always run with interrupts enabled
 (however, they can temporarily disable interrupts if needed). These
@@ -54,13 +59,13 @@ 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.
@@ -74,7 +79,7 @@ interrupts disabled.
 Much of the functionality of the micro-controller involves working
 with General-Purpose Input/Output pins (GPIO). In order to abstract
 the low-level architecture specific code from the high-level task
-code, all GPIO events are implemented in architectures specific
+code, all GPIO events are implemented in architecture specific
 wrappers (eg, **src/avr/gpio.c**). The code is compiled with gcc's
 "-flto -fwhole-program" optimization which does an excellent job of
 inlining functions across compilation units, so most of these tiny
@@ -92,8 +97,8 @@ 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 +111,325 @@ 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.
+
+  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 (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 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.
+
+Adding a host module
+====================
+
+The Klippy host code has a dynamic module loading capability. If a
+config section named "[my_module]" is found in the printer config file
+then the software will automatically attempt to load the python module
+klippy/extras/my_module.py . This module system is the preferred
+method for adding new functionality to Klipper.
+
+The easiest way to add a new module is to use an existing module as a
+reference - see **klippy/extras/servo.py** as an example.
+
+The following may also be useful:
+* Execution of the module starts in the module level `load_config()`
+  function (for config sections of the form [my_module]) or in
+  `load_config_prefix()` (for config sections of the form
+  [my_module my_name]). This function is passed a "config" object and
+  it must return a new "printer object" associated with the given
+  config section.
+* During the process of instantiating a new printer object, the config
+  object can be used to read parameters from the given config
+  section. This is done using `config.get()`, `config.getfloat()`,
+  `config.getint()`, etc. methods. Be sure to read all values from the
+  config during the construction of the printer object - if the user
+  specifies a config parameter that is not read during this phase then
+  it will be assumed it is a typo in the config and an error will be
+  raised.
+* Use the `config.get_printer()` method to obtain a reference to the
+  main "printer" class. This "printer" class stores references to all
+  the "printer objects" that have been instantiated. Use the
+  `printer.lookup_object()` method to find references to other printer
+  objects. Almost all functionality (even core kinematic modules) are
+  encapsulated in one of these printer objects. Note, though, that
+  when a new module is instantiated, not all other printer objects
+  will have been instantiated. The "gcode" and "pins" modules will
+  always be available, but for other modules it is a good idea to
+  defer the lookup.
+* Define a `printer_state()` method if the code needs to be called
+  during printer setup and/or shutdown. This method is called twice
+  during setup (with "connect" and then "ready") and may also be
+  called at run-time (with "shutdown" or "disconnect"). It is common
+  to perform "printer object" lookup during the "connect" and "ready"
+  phases.
+* If there is an error in the user's config, be sure to raise it
+  during the `load_config()` or `printer_state("connect")` phases. Use
+  either `raise config.error("my error")` or `raise
+  printer.config_error("my error")` to report the error.
+* Use the "pins" module to configure a pin on a micro-controller. This
+  is typically done with something similar to
+  `printer.lookup_object("pins").setup_pin("pwm",
+  config.get("my_pin"))`. The returned object can then be commanded at
+  run-time.
+* If the module needs access to system timing or external file
+  descriptors then use `printer.get_reactor()` to obtain access to the
+  global "event reactor" class. This reactor class allows one to
+  schedule timers, wait for input on file descriptors, and to "sleep"
+  the host code.
+* Do not use global variables. All state should be stored in the
+  printer object returned from the `load_config()` function. This is
+  important as otherwise the RESTART command may not perform as
+  expected. Also, for similar reasons, if any external files (or
+  sockets) are opened then be sure to close them from the
+  `printer_state("disconnect")` callback.
+* Avoid accessing the internal member variables (or calling methods
+  that start with an underscore) of other printer objects. Observing
+  this convention makes it easier to manage future changes.
+* If submitting the module for inclusion in the main Klipper code, be
+  sure to place a copyright notice at the top of the module. See the
+  existing modules for the preferred format.
+
+Adding new kinematics
+=====================
+
+This section provides some tips on adding support to Klipper for
+additional types of printer kinematics. This type of activity requires
+excellent understanding of the math formulas for the target
+kinematics. It also requires software development skills - though one
+should only need to update the host software (which is written in
+Python).
+
+Useful steps:
+1. Start by studying the [above section](#code-flow-of-a-move-command)
+   and the [Kinematics document](Kinematics.md).
+2. Review the existing kinematic classes in cartesian.py, corexy.py,
+   and delta.py. The kinematic classes are tasked with converting a
+   move in cartesian coordinates to the movement on each stepper. One
+   should be able to copy one of these files as a starting point.
+3. Implement the `get_postion()` method in the new kinematics
+   class. This method converts the current stepper position of each
+   stepper axis (stored in millimeters) to a position in cartesian
+   space (also in millimeters).
+4. Implement the `set_postion()` method. This is the inverse of
+   get_position() - it sets each axis position (in millimeters) given
+   a position in cartesian coordinates.
+5. Implement the `move()` method. The goal of the move() method is to
+   convert a move defined in cartesian space to a series of stepper
+   step times that implement the requested movement.
+   * The `move()` method is passed a "print_time" parameter (which
+     stores a time in seconds) and a "move" class instance that fully
+     defines the movement. The goal is to repeatedly invoke the
+     `stepper.step()` method with the time (relative to print_time)
+     that each stepper should step at to obtain the desired motion.
+   * One "trick" to help with the movement calculations is to imagine
+     there is a physical rail between `move.start_pos` and
+     `move.end_pos` that confines the print head so that it can only
+     move along this straight line of motion. Then, if the head is
+     confined to that imaginary rail, the head is at `move.start_pos`,
+     only one stepper is enabled (all other steppers can move freely),
+     and the given stepper is stepped a single step, then one can
+     imagine that the head will move along the line of movement some
+     distance. Determine the formula converting this step distance to
+     distance along the line of movement. Once one has the distance
+     along the line of movement, one can figure out the time that the
+     head should be at that position (using the standard formulas for
+     velocity and acceleration). This time is the ideal step time for
+     the given stepper and it can be passed to the `stepper.step()`
+     method.
+   * The `stepper.step()` method must always be called with an
+     increasing time for a given stepper (steps must be scheduled in
+     the order they are to be executed). A common error during
+     kinematic development is to receive an "Internal error in
+     stepcompress" failure - this is generally due to the step()
+     method being invoked with a time earlier than the last scheduled
+     step. For example, if the last step in move1 is scheduled at a
+     time greater than the first step in move2 it will generally
+     result in the above error.
+   * Fractional steps. Be aware that a move request is given in
+     cartesian space and it is not confined to discreet
+     locations. Thus a move's start and end locations may translate to
+     a location on a stepper axis that is between two steps (a
+     fractional step). The code must handle this. The preferred
+     approach is to schedule the next step at the time a move would
+     position the stepper axis at least half way towards the next
+     possible step location. Incorrect handling of fractional steps is
+     a common cause of "Internal error in stepcompress" failures.
+6. Other methods. The `home()`, `check_move()`, and other methods
+   should also be implemented. However, at the start of development
+   one can use empty code here.
+7. Implement test cases. Create a g-code file with a series of moves
+   that can test important cases for the given kinematics. Follow the
+   [debugging documentation](Debugging.md) to convert this g-code file
+   to micro-controller commands. This is useful to exercise corner
+   cases and to check for regressions.
+8. Optimize if needed. One may notice that the existing kinematic
+   classes do not call `stepper.step()`. This is purely an
+   optimization - the inner loop of the kinematic calculations were
+   moved to C to reduce load on the host cpu. All of the existing
+   kinematic classes started development using `stepper.step()` and
+   then were later optimized. The g-code to mcu command translation
+   (described in the previous step) is a useful tool during
+   optimization - if a code change is purely an optimization then it
+   should not impact the resulting text representation of the mcu
+   commands (though minor changes in output due to floating point
+   rounding are possible). So, one can use this system to detect
+   regressions.
+
+Time
+====
+
+Fundamental to the operation of Klipper is the handling of clocks,
+times, and timestamps. Klipper executes actions on the printer by
+scheduling events to occur in the near future. For example, to turn on
+a fan, the code might schedule a change to a GPIO pin in a 100ms. It
+is rare for the code to attempt to take an instantaneous action. Thus,
+the handling of time within Klipper is critical to correct operation.
+
+There are three types of times tracked internally in the Klipper host
+software:
+* System time. The system time uses the system's monotonic clock - it
+  is a floating point number stored as seconds and it is (generally)
+  relative to when the host computer was last started. System times
+  have limited use in the software - they are primarily used when
+  interacting with the operating system. Within the host code, system
+  times are frequently stored in variables named *eventtime* or
+  *curtime*.
+* Print time. The print time is synchronized to the main
+  micro-controller clock (the micro-controller defined in the "[mcu]"
+  config section). It is a floating point number stored as seconds and
+  is relative to when the main mcu was last restarted. It is possible
+  to convert from a "print time" to the main micro-controller's
+  hardware clock by multiplying the print time by the mcu's statically
+  configured frequency rate. The high-level host code uses print times
+  to calculates almost all physical actions (eg, head movement, heater
+  changes, etc.). Within the host code, print times are generally
+  stored in variables named *print_time* or *move_time*.
+* MCU clock. This is the hardware clock counter on each
+  micro-controller. It is stored as an integer and its update rate is
+  relative to the frequency of the given micro-controller. The host
+  software translates its internal times to clocks before transmission
+  to the mcu. The mcu code only ever tracks time in clock
+  ticks. Within the host code, clock values are tracked as 64bit
+  integers, while the mcu code uses 32bit integers. Within the host
+  code, clocks are generally stored in variables with names containing
+  *clock* or *ticks*.
+
+Conversion between the different time formats is primarily implemented
+in the **klippy/clocksync.py** code.
+
+Some things to be aware of when reviewing the code:
+* 32bit and 64bit clocks: To reduce bandwidth and to improve
+  micro-controller efficiency, clocks on the micro-controller are
+  tracked as 32bit integers. When comparing two clocks in the mcu
+  code, the `timer_is_before()` function must always be used to ensure
+  integer rollovers are handled properly. The host software converts
+  32bit clocks to 64bit clocks by appending the high-order bits from
+  the last mcu timestamp it has received - no message from the mcu is
+  ever more than 2^31 clock ticks in the future or past so this
+  conversion is never ambiguous. The host converts from 64bit clocks
+  to 32bit clocks by simply truncating the high-order bits. To ensure
+  there is no ambiguity in this conversion, the
+  **klippy/serialqueue.c** code will buffer messages until they are
+  within 2^31 clock ticks of their target time.
+* Multiple micro-controllers: The host software supports using
+  multiple micro-controllers on a single printer. In this case, the
+  "MCU clock" of each micro-controller is tracked separately. The
+  clocksync.py code handles clock drift between micro-controllers by
+  modifying the way it converts from "print time" to "MCU clock". On
+  secondary mcus, the mcu frequency that is used in this conversion is
+  regularly updated to account for measured drift.

docs/Config_checks.md

@@ -0,0 +1,147 @@
+This document provides a list of steps to help confirm the pin
+settings in the Klipper printer.cfg file.  It is a good idea to run
+through these steps after following the steps in the
+[installation document](Installation.md).
+
+During this guide, it may be necessary to make changes to the Klipper
+config file. Be sure to issue a RESTART command after every change to
+the config file to ensure that the change takes effect (type "restart"
+in the Octoprint terminal tab and then click "Send"). It's also a good
+idea to issue a STATUS command after every RESTART to verify that the
+config file is successfully loaded.
+
+### Verify temperature
+
+Start by verifying that temperatures are being properly
+reported. Navigate to the Octoprint temperature tab.
+
+![octoprint-temperature](img/octoprint-temperature.png)
+
+Verify that the temperature of the nozzle and bed (if applicable) are
+present and not increasing. If it is increasing, remove power from the
+printer. If the temperatures are not accurate, review the
+"sensor_type" and "sensor_pin" settings for the nozzle and/or bed.
+
+### Verify M112
+
+Navigate to the Octoprint terminal tab and issue an M112 command in
+the terminal box. This command requests Klipper to go into a
+"shutdown" state. It will cause Octoprint to disconnect from Klipper -
+navigate to the Connection area and click on "Connect" to cause
+Octoprint to reconnect. Then navigate to the Octoprint temperature tab
+and verify that temperatures continue to update and the temperatures
+are not increasing. If temperatures are increasing, remove power from
+the printer.
+
+The M112 command causes Klipper to go into a "shutdown" state. To
+clear this state, issue a FIRMWARE_RESTART command in the Octoprint
+terminal tab.
+
+### Verify heaters
+
+Navigate to the Octoprint temperature tab and type in 50 followed by
+enter in the "Tool" temperature box. The extruder temperature in the
+graph should start to increase (within about 30 seconds or so). Then
+go to the "Tool" temperature drop-down box and select "Off". After
+several minutes the temperature should start to return to its initial
+room temperature value. If the temperature does not increase then
+verify the "heater_pin" setting in the config.
+
+If the printer has a heated bed then perform the above test again with
+the bed.
+
+### Verify stepper motor enable pin
+
+Verify that all of the printer axes can manually move freely (the
+stepper motors are disabled). If not, issue an M84 command to disable
+the motors. If any of the axes still can not move freely, then verify
+the stepper "enable_pin" configuration for the given axis. On most
+commodity stepper motor drivers, the motor enable pin is "active low"
+and therefore the enable pin should have a "!" before the pin (for
+example, "enable_pin: !ar38").
+
+### Verify endstops
+
+Manually move all the printer axes so that none of them are in contact
+with an endstop. Send a QUERY_ENDSTOPS command via the Octoprint
+terminal tab. It should respond with the current state of all of the
+configured endstops and they should all report a state of "open". For
+each of the endstops, rerun the QUERY_ENDSTOPS command while manually
+triggering the endstop. The QUERY_ENDSTOPS command should report the
+endstop as "TRIGGERED".
+
+If the endstop appears inverted (it reports "open" when triggered and
+vice-versa) then add a "!" to the pin definition (for example,
+"endstop_pin: ^!ar3"), or remove the "!" if there is already one
+present.
+
+If the endstop does not change at all then it generally indicates that
+the endstop is connected to a different pin. However, it may also
+require a change to the pullup setting of the pin (the '^' at the
+start of the endstop_pin name - most printers will use a pullup
+resistor and the '^' should be present).
+
+### Verify stepper motor direction
+
+Make sure the printer.cfg file does not have "homing_speed" set for
+any axis (or set it to a value of 5 or less).
+
+On cartesian style printers, manually move the X axis to a midway
+point, issue a G28X0 command, and verify that the X motor moves slowly
+towards the endstop defined for that axis. If the motor moves in the
+wrong direction issue an M112 command to abort the move. A wrong
+direction generally indicates that the "dir_pin" for the axis needs to
+be inverted. This is done by adding a '!' to the "dir_pin" in the
+printer config file (or removing it if one is already there). For
+example, change "dir_pin: xyz" to "dir_pin: !xyz". Then RESTART and
+retest the axis. If the axis does not move at all, then verify the
+"enable_pin" and "step_pin" settings for the axis. For cartesian style
+printers, repeat the test for the Y and Z axis with G28Y0 and G28Z0.
+
+For delta style printers, manually move all three carriages to a
+midway point and then issue a G28 command. Verify all three motors
+move simultaneously upwards. If not, issue an M112 command and follow
+the troubleshooting steps in the preceding paragraph.
+
+### Verify extruder motor
+
+To test the extruder motor it will be necessary to heat the extruder
+to a printing temperature. Navigate to the Octoprint temperature tab
+and select a target temperature from the temperature drop-down box (or
+manually enter an appropriate temperature). Wait for the printer to
+reach the desired temperature. Then navigate to the Octoprint control
+tab and click the "Extrude" button. Verify that the extruder motor
+turns in the correct direction. If it does not, see the
+troubleshooting tips in the previous section to confirm the
+"enable_pin", "step_pin", and "dir_pin" settings for the extruder.
+
+### Calibrate PID settings
+
+Klipper supports
+[PID control](https://en.wikipedia.org/wiki/PID_controller) for the
+extruder and bed heaters. In order to use this control mechanism it is
+necessary to calibrate the PID settings on each printer. (PID settings
+found in other firmwares or in the example configuration files often
+work poorly.)
+
+To calibrate the extruder, navigate to the OctoPrint terminal tab and
+run the PID_CALIBRATE command. For example: `PID_CALIBRATE
+HEATER=extruder TARGET=170`
+
+At the completion of the tuning test, update the printer.cfg file with
+the recommended pid_Kp, pid_Ki, and pid_Kd values.
+
+If the printer has a heated bed and it supports being driven by PWM
+(Pulse Width Modulation) then it is recommended to use PID control for
+the bed. (When the bed heater is controlled using the PID algorithm it
+may turn on and off ten times a second, which may not be suitable for
+heaters using a mechanical switch.) A typical bed PID calibration
+command is: `PID_CALIBRATE HEATER=heater_bed TARGET=60`
+
+### Next steps
+
+This guide is intended to help with basic verification of pin settings
+in the Klipper configuration file. It may be necessary to perform
+detailed printer calibration - a number of guides are available online
+to help with this (for example, do a web search for "3d printer
+calibration").

docs/Contact.md

@@ -0,0 +1,51 @@
+This page provides information on how to contact the Klipper
+developers.
+
+Issue reporting
+===============
+
+In order to report a problem or request a change in behavior, it is
+necessary to collect the Klipper log file. The first step is to
+**issue an M112 command** in the OctoPrint terminal window immediately
+after the undesirable event occurs. This causes Klipper to go into a
+"shutdown state" and it will cause additional debugging information to
+be written to the log file.
+
+Issue requests are submitted through Github.  **All issues must
+include the full /tmp/klippy.log log file from the session that
+produced the error.** An "scp" and/or "sftp" utility is needed to
+acquire this log file. The "scp" utility comes standard with Linux and
+MacOS desktops. There are freely available scp utilities for other
+desktops (eg, WinSCP).
+
+Use the scp utility to copy the `/tmp/klippy.log` file from the host
+machine to your desktop. It is a good idea to compress the klippy.log
+file before posting it (eg, using zip or gzip). Open a new issue at
+https://github.com/KevinOConnor/klipper/issues , provide a description
+of the problem, and **attach the `klippy.log` file to the issue**:
+![attach-issue](img/attach-issue.png)
+
+Mailing list
+============
+
+There is a mailing list for general discussions on Klipper. In order
+to send am email to the list, one must first subscribe:
+https://www.freelists.org/list/klipper . Once subscribed, emails may
+be sent to `klipper@freelists.org`.
+
+Archives of the mailing list are available at:
+https://www.freelists.org/archive/klipper/
+
+IRC
+===
+
+One may join the #klipper channel on freenode.net (
+irc://chat.freenode.net:6667 ).
+
+To communicate in this IRC channel one will need an IRC
+client. Configure it to connect to chat.freenode.net on port 6667 and
+join the #klipper channel (`/join #klipper`).
+
+If asking a question on IRC, be sure to ask the question and then stay
+connected to the channel to receive responses. Due to timezone
+differences, it may take several hours before receiving a response.

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, set
+the MCU frequency to 20Mhz, and select SIMULAVR software emulation
+support. 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
@@ -119,13 +115,59 @@ gtkwave avrsim.vcd
 ```
 
 Manually sending commands to the micro-controller
--------------------------------------------------
+=================================================
 
-Normally, Klippy would be used to translate gcode commands to Klipper
-commands. However, it's also possible to manually send Klipper
-commands (functions marked with the DECL_COMMAND() macro in the
-Klipper source code). To do so, run:
+Normally, the host klippy.py process would be used to translate gcode
+commands to Klipper micro-controller commands. However, it's also
+possible to manually send these MCU commands (functions marked with
+the DECL_COMMAND() macro in the Klipper source code). To do so, run:
 
 ```
 ~/klippy-env/bin/python ./klippy/console.py /tmp/pseudoserial 250000
 ```
+
+See the "HELP" command within the tool for more information on its
+functionality.
+
+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.
+
+Extracting information from the klippy.log file
+===============================================
+
+The Klippy log file (/tmp/klippy.log) also contains debugging
+information. There is a logextract.py script that may be useful when
+analyzing a micro-controller shutdown or similar problem. It is
+typically run with something like:
+
+```
+mkdir work_directory
+cd work_directory
+cp /tmp/klippy.log .
+~/klipper/scripts/logextract.py ./klippy.log
+```
+
+The script will extract the printer config file and will extract MCU
+shutdown information. The information dumps from an MCU shutdown (if
+present) will be reordered by timestamp to assist in diagnosing cause
+and effect scenarios.

docs/FAQ.md

@@ -0,0 +1,252 @@
+Frequently asked questions
+==========================
+
+1. [How can I donate to the project?](#how-can-i-donate-to-the-project)
+2. [How do I calculate the step_distance parameter in the printer config file?](#how-do-i-calculate-the-step_distance-parameter-in-the-printer-config-file)
+3. [Where's my serial port?](#wheres-my-serial-port)
+4. [The "make flash" command doesn't work](#the-make-flash-command-doesnt-work)
+5. [How do I change the serial baud rate?](#how-do-i-change-the-serial-baud-rate)
+6. [Can I run Klipper on something other than a Raspberry Pi 3?](#can-i-run-klipper-on-something-other-than-a-raspberry-pi-3)
+7. [Why can't I move the stepper before homing the printer?](#why-cant-i-move-the-stepper-before-homing-the-printer)
+8. [Why is the Z position_endstop set to 0.5 in the default configs?](#why-is-the-z-position_endstop-set-to-05-in-the-default-configs)
+9. [I converted my config from Marlin and the X/Y axes work fine, but I just get a screeching noise when homing the Z axis](#i-converted-my-config-from-marlin-and-the-xy-axes-work-fine-but-i-just-get-a-screeching-noise-when-homing-the-z-axis)
+10. [When I set "restart_method=command" my AVR device just hangs on a restart](#when-i-set-restart_methodcommand-my-avr-device-just-hangs-on-a-restart)
+11. [Will the heaters be left on if the Raspberry Pi crashes?](#will-the-heaters-be-left-on-if-the-raspberry-pi-crashes)
+12. [How do I upgrade to the latest software?](#how-do-i-upgrade-to-the-latest-software)
+
+### How can I donate to the project?
+
+Thanks. Kevin has a Patreon page at: https://www.patreon.com/koconnor
+
+### How do I calculate the step_distance parameter in the printer config file?
+
+If you know the steps per millimeter for the axis then use a
+calculator to divide 1.0 by steps_per_mm. Then round this number to
+six decimal places and place it in the config (six decimal places is
+nano-meter precision).
+
+The step_distance defines the distance that the axis will travel on
+each motor driver pulse. It can also be calculated from the axis
+pitch, motor step angle, and driver microstepping. If unsure, do a web
+search for "calculate steps per mm" to find an online calculator.
+
+### Where's my serial port?
+
+The general way to find a USB serial port is to run `ls -l
+/dev/serial/by-id/` from an ssh terminal on the host machine. It will
+likely produce output similar to the following:
+```
+lrwxrwxrwx 1 root root 13 Jan 3 22:15 usb-UltiMachine__ultimachine.com__RAMBo_12345678912345678912-if00 -> ../../ttyACM0
+```
+
+The name found in the above command is stable and it is possible to
+use it in the config file and while flashing the micro-controller
+code. For example, a flash command might look similar to:
+```
+sudo service klipper stop
+make flash FLASH_DEVICE=/dev/serial/by-id/usb-UltiMachine__ultimachine.com__RAMBo_12345678912345678912-if00
+sudo service klipper start
+```
+and the updated config might look like:
+```
+[mcu]
+serial: /dev/serial/by-id/usb-UltiMachine__ultimachine.com__RAMBo_12345678912345678912-if00
+```
+
+Be sure to copy-and-paste the name from the "ls" command that you ran
+above as the name will be different for each printer.
+
+### The "make flash" command doesn't work
+
+The code attempts to flash the device using the most common method for
+each platform. Unfortunately, there is a lot of variance in flashing
+methods, so the "make flash" command may not work on all boards.
+
+If you're having an intermittent failure or you do have a standard
+setup, then double check that Klipper isn't running when flashing
+(sudo service klipper stop), make sure OctoPrint isn't trying to
+connect directly to the device (open the Connection tab in the web
+page and click Disconnect if the Serial Port is set to the device),
+and make sure FLASH_DEVICE is set correctly for your board (see the
+[question above](#wheres-my-serial-port)).
+
+However, if "make flash" just doesn't work for your board, then you
+will need to manually flash. See if there is a config file in the
+[config directory](../config) with specific instructions for flashing
+the device. Also, check the board manufacturer's documentation to see
+if it describes how to flash the device. Finally, on AVR devices, it
+may be possible to manually flash the device using
+[avrdude](http://www.nongnu.org/avrdude/) with custom command-line
+parameters - see the avrdude documentation for further information.
+
+### How do I change the serial baud rate?
+
+The default baud rate is 250000 in both the Klipper micro-controller
+configuration and in the Klipper host software. This works on almost
+all micro-controllers and it is the recommended setting. (Most online
+guides that refer to a baud rate of 115200 are outdated.)
+
+If you need to change the baud rate, then the new rate will need to be
+configured in the micro-controller (during **make menuconfig**) and
+that updated code will need to be flashed to the micro-controller. The
+Klipper printer.cfg file will also need to be updated to match that
+baud rate (see the example.cfg file for details).  For example:
+```
+[mcu]
+baud: 250000
+```
+
+The baud rate shown on the OctoPrint web page has no impact on the
+internal Klipper micro-controller baud rate. Always set the OctoPrint
+baud rate to 250000 when using Klipper.
+
+### Can I run Klipper on something other than a Raspberry Pi 3?
+
+The recommended hardware is a Raspberry Pi 2 or a Raspberry
+Pi 3.
+
+Klipper will run on a Raspberry Pi 1 and on the Raspberry Pi Zero, but
+these boards don't have enough processing power to run OctoPrint
+well. It's not uncommon for print stalls to occur on these slower
+machines (the printer may move faster than OctoPrint can send movement
+commands) when printing directly from OctoPrint. If you wish to run on
+one one of these slower boards anyway, consider using the
+"virtual_sdcard" feature (see
+[config/example-extras.cfg](../config/example-extras.cfg) for details)
+when printing.
+
+For running on the Beaglebone, see the
+[Beaglebone specific installation instructions](beaglebone.md).
+
+Klipper has been run on other machines.  The Klipper host software
+only requires Python running on a Linux (or similar)
+computer. However, if you wish to run it on a different machine you
+will need Linux admin knowledge to install the system prerequisites
+for that particular machine. See the
+[install-octopi.sh](../scripts/install-octopi.sh) script for further
+information on the necessary Linux admin steps.
+
+### Why can't I move the stepper before homing the printer?
+
+The code does this to reduce the chance of accidentally commanding the
+head into the bed or a wall. Once the printer is homed the software
+attempts to verify each move is within the position_min/max defined in
+the config file. If the motors are disabled (via an M84 or M18
+command) then the motors will need to be homed again prior to
+movement.
+
+If you want to move the head after canceling a print via OctoPrint,
+consider changing the OctoPrint cancel sequence to do that for
+you. It's configured in OctoPrint via a web browser under:
+Settings->GCODE Scripts
+
+If you want to move the head after a print finishes, consider adding
+the desired movement to the "custom g-code" section of your slicer.
+
+### Why is the Z position_endstop set to 0.5 in the default configs?
+
+For cartesian style printers the Z position_endstop specifies how far
+the nozzle is from the bed when the endstop triggers. If possible, it
+is recommended to use a Z-max endstop and home away from the bed (as
+this reduces the potential for bed collisions). However, if one must
+home towards the bed then it is recommended to position the endstop so
+it triggers when the nozzle is still a small distance away from the
+bed. This way, when homing the axis, it will stop before the nozzle
+touches the bed.
+
+Almost all mechanical switches can still move a small distance
+(eg, 0.5mm) after they are triggered. So, for example, if the
+position_endstop is set to 0.5mm then one may still command the
+printer to move to Z0.2. The position_min config setting (which
+defaults to 0) is used to specify the minimum Z position one may
+command the printer to move to.
+
+Note, the Z position_endstop specifies the distance from the nozzle to
+the bed when the nozzle and bed (if applicable) are hot. It is typical
+for thermal expansion to cause nozzle expansion of around .1mm, which
+is also the typical thickness of a sheet of printer paper. Thus, it is
+common to use the "paper test" to confirm calibration of the Z
+height - check that the bed and nozzle are at room temperature, check
+that there is no plastic on the head or bed, home the printer, place a
+piece of paper between the nozzle and bed, and repeatedly command the
+head to move closer to the bed checking each time if you feel a small
+amount of friction when sliding the paper between bed and nozzle - if
+all is calibrated well a small amount of friction would be felt when
+the height is at Z0.
+
+### I converted my config from Marlin and the X/Y axes work fine, but I just get a screeching noise when homing the Z axis
+
+Short answer: Try reducing the max_z_velocity setting in the printer
+config. Also, if the Z stepper is moving in the wrong direction, try
+inverting the dir_pin setting in the config (eg, "dir_pin: !xyz"
+instead of "dir_pin: xyz").
+
+Long answer: In practice Marlin can typically only step at a rate of
+around 10000 steps per second. If it is requested to move at a speed
+that would require a higher step rate then Marlin will generally just
+step as fast as it can. Klipper is able to achieve much higher step
+rates, but the stepper motor may not have sufficient torque to move at
+a higher speed. So, for a Z axis with a very precise step_distance the
+actual obtainable max_z_velocity may be smaller than what is
+configured in Marlin.
+
+### When I set "restart_method=command" my AVR device just hangs on a restart
+
+Some old versions of the AVR bootloader have a known bug in watchdog
+event handling. This typically manifests when the printer.cfg file has
+restart_method set to "command". When the bug occurs, the AVR device
+will be unresponsive until power is removed and reapplied to the
+device (the power or status LEDs may also blink repeatedly until the
+power is removed).
+
+The workaround is to use a restart_method other than "command" or to
+flash an updated bootloader to the AVR device. Flashing a new
+bootloader is a one time step that typically requires an external
+programmer - search the web to find the instructions for your
+particular device.
+
+### Will the heaters be left on if the Raspberry Pi crashes?
+
+The software has been designed to prevent that. Once the host enables
+a heater, the host software needs to confirm that enablement every 5
+seconds. If the micro-controller does not receive a confirmation every
+5 seconds it goes into a "shutdown" state which is designed to turn
+off all heaters and stepper motors.
+
+See the "config_digital_out" command in the
+[MCU commands](MCU_Commands.md) document for further details.
+
+### How do I upgrade to the latest software?
+
+The general way to upgrade is to ssh into the Raspberry Pi and run:
+
+```
+cd ~/klipper
+git pull
+~/klipper/scripts/install-octopi.sh
+```
+
+Then one can recompile and flash the micro-controller code. For
+example:
+
+```
+sudo service klipper stop
+make flash FLASH_DEVICE=/dev/ttyACM0
+sudo service klipper start
+```
+
+However, it's often the case that only the host software changes. In
+this case, one can update and restart just the host software with:
+
+```
+cd ~/klipper
+git pull
+sudo service klipper restart
+```
+
+If after using this shortcut the software warns about needing to
+reflash the micro-controller or some other unusual error occurs, then
+follow the full upgrade steps outlined above. Note that the RESTART
+and FIRMWARE_RESTART g-code commands do not load new software - the
+above "sudo service klipper restart" and "make flash" commands are
+needed for a software change to take effect.

docs/Features.md

@@ -1,26 +1,24 @@
-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
   movements. The application processor determines when to step each
   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.
+  at the requested time. Each stepper event is scheduled with a
+  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
-  are possible. Higher stepper rates enable higher print
-  velocities. The stepper event timing remains precise even at high
-  speeds which improves overall stability.
+  micro-controller can obtain rates over 175K steps per second. On
+  more recent micro-controllers, rates over 500K 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.
 
 * Configuration via simple config file. There's no need to reflash the
   micro-controller to change a setting. All of Klipper's configuration
@@ -34,16 +32,29 @@ 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 supports printers with multiple micro-controllers. For
+    example, one micro-controller could be used to control an
+    extruder, while another could control the printer's heaters, while
+    a third controls the rest of the printer. The Klipper host
+    software implements clock synchronization to account for clock
+    drift between micro-controllers. No special code is needed to
+    enable multiple micro-controllers - it just requires a few extra
+    lines in the config file.
+  * 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 +76,12 @@ 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
 ===============
@@ -78,8 +89,14 @@ Step Benchmarks
 Below are the results of stepper performance tests. The numbers shown
 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              |
+| Micro-controller  | Fastest step rate | 3 steppers active |
+| ----------------- | ----------------- | ----------------- |
+| 20Mhz AVR         | 189K              | 125K              |
+| 16Mhz AVR         | 151K              | 100K              |
+| Arduino Due (ARM) | 382K              | 337K              |
+| Beaglebone PRU    | 689K              | 689K              |
+
+On AVR platforms, the highest achievable step rate is with just one
+stepper stepping. On the Due, the highest step rate is with two
+simultaneous steppers stepping. On the PRU, the highest step rate is
+with three simultaneous steppers.

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/G-Codes.md

@@ -0,0 +1,131 @@
+This document describes the commands that Klipper supports. These are
+commands that one may enter into the OctoPrint terminal tab.
+
+# G-Code commands
+
+Klipper supports the following standard G-Code commands:
+- Move (G0 or G1): `G1 [X<pos>] [Y<pos>] [Z<pos>] [E<pos>] [F<speed>]`
+- Dwell: `G4 P<milliseconds>`
+- Move to origin: `G28 [X] [Y] [Z]`
+- Turn off motors: `M18` or `M84`
+- Wait for current moves to finish: `M400`
+- Select tool: `T<index>`
+- Use absolute/relative distances for extrusion: `M82`, `M83`
+- Use absolute/relative coordinates: `G90`, `G91`
+- Set position: `G92 [X<pos>] [Y<pos>] [Z<pos>] [E<pos>]`
+- Set speed factor override percentage: `M220 S<percent>`
+- Set extrude factor override percentage: `M221 S<percent>`
+- Get extruder temperature: `M105`
+- Set extruder temperature: `M104 [T<index>] [S<temperature>]`
+- Set extruder temperature and wait: `M109 [T<index>] S<temperature>`
+- Set bed temperature: `M140 [S<temperature>]`
+- Set bed temperature and wait: `M190 S<temperature>`
+- Set fan speed: `M106 S<value>`
+- Turn fan off: `M107`
+- Emergency stop: `M112`
+- Get current position: `M114`
+- Get firmware version: `M115`
+- Set home offset: `M206 [X<pos>] [Y<pos>] [Z<pos>]`
+
+For further details on the above commands see the
+[RepRap G-Code documentation](http://reprap.org/wiki/G-code).
+
+Klipper's goal is to support the G-Code commands produced by common
+3rd party software (eg, OctoPrint, Printrun, Slic3r, Cura, etc.) in
+their standard configurations. It is not a goal to support every
+possible G-Code command. Instead, Klipper prefers human readable
+["extended G-Code commands"](#extended-g-code-commands).
+
+## G-Code SD card commands
+
+Klipper also supports the following standard G-Code commands if the
+"virtual_sdcard" config section is enabled:
+- List SD card: `M20`
+- Initialize SD card: `M21`
+- Select SD file: `M23 <filename>`
+- Start/resume SD print: `M24`
+- Pause SD print: `M25`
+- Set SD position: `M26 S<offset>`
+- Report SD print status: `M27`
+
+# Extended G-Code Commands
+
+Klipper uses "extended" G-Code commands for general configuration and
+status.  These extended commands all follow a similar format - they
+start with a command name and may be followed by one or more
+parameters. For example: `SET_SERVO SERVO=myservo ANGLE=5.3`. In this
+document, the commands and parameters are shown in uppercase, however
+they are not case sensitive. (So, "SET_SERVO" and "set_servo" both run
+the same command.)
+
+The following standard commands are supported:
+- `QUERY_ENDSTOPS`: Probe the axis endstops and report if they are
+  "triggered" or in an "open" state. This command is typically used to
+  verify that an endstop is working correctly.
+- `GET_POSITION`: Return information on the current location of the
+  toolhead.
+- `PID_CALIBRATE HEATER=<config_name> TARGET=<temperature>
+  [WRITE_FILE=1]`: Perform a PID calibration test. The specified
+  heater will be enabled until the specified target temperature is
+  reached, and then the heater will be turned off and on for several
+  cycles. If the WRITE_FILE parameter is enabled, then the file
+  /tmp/heattest.txt will be created with a log of all temperature
+  samples taken during the test.
+- `RESTART`: This will cause the host software to reload its config
+  and perform an internal reset. This command will not clear error
+  state from the micro-controller (see FIRMWARE_RESTART) nor will it
+  load new software (see
+  [the FAQ](FAQ.md#how-do-i-upgrade-to-the-latest-software)).
+- `FIRMWARE_RESTART`: This is similar to a RESTART command, but it
+  also clears any error state from the micro-controller.
+- `STATUS`: Report the Klipper host software status.
+- `HELP`: Report the list of available extended G-Code commands.
+
+## Custom Pin Commands
+
+The following command is available when an "output_pin" config section
+is enabled:
+- `SET_PIN PIN=config_name VALUE=<value>`
+
+## Servo Commands
+
+The following commands are available when a "servo" config section is
+enabled:
+- `SET_SERVO SERVO=config_name WIDTH=<seconds>`
+- `SET_SERVO SERVO=config_name ANGLE=<degrees>`
+
+## Probe
+
+The following commands are available when a "probe" config section is
+enabled:
+- `PROBE`: Move the nozzle downwards until the probe triggers.
+- `QUERY_PROBE`: Report the current status of the probe ("triggered"
+  or "open").
+
+## Delta Calibration
+
+The following commands are available when the "delta_calibrate" config
+section is enabled:
+- `DELTA_CALIBRATE`: This command will probe seven points on the bed
+  and recommend updated endstop positions, tower angles, and radius.
+  - `NEXT`: If manual bed probing is enabled, then one can use this
+    command to move to the next probing point during a DELTA_CALIBRATE
+    operation.
+
+## Bed Tilt
+
+The following commands are available when the "bed_tilt" config
+section is enabled:
+- `BED_TILT_CALIBRATE`: This command will probe the points specified
+  in the config and then recommend updated x and y tilt adjustments.
+  - `NEXT`: If manual bed probing is enabled, then one can use this
+    command to move to the next probing point during a
+    BED_TILT_CALIBRATE operation.
+
+## Dual Carriages
+
+The following command is available when the "dual_carriage" config
+section is enabled:
+- `SET_DUAL_CARRIAGE CARRIAGE=[0|1]`: This command will set the active
+  carriage. It is typically invoked from the activate_gcode and
+  deactivate_gcode fields in a multiple extruder configuration.

docs/Installation.md

@@ -1,113 +1,82 @@
-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
+(see the
+[FAQ](FAQ.md#can-i-run-klipper-on-something-other-than-a-raspberry-pi-3)
+for other machines).
 
-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.
+Klipper currently supports Atmel ATmega based micro-controllers,
+Arduino Due (Atmel SAM3x8e ARM micro-controller), and
+[Beaglebone PRU](beaglebone.md) based printers.
 
 Prepping an OS image
 ====================
 
 Start by installing [OctoPi](https://github.com/guysoft/OctoPi) on the
-Raspberry Pi computer. Use OctoPi v0.13.0 or later - see the
+Raspberry Pi computer. Use OctoPi v0.14.0 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 v1.3.5 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:
+After installing OctoPi and upgrading OctoPrint, it will be necessary
+to ssh into the target machine to run a handful of system commands. If
+using a Linux or MacOS desktop, then the "ssh" software should already
+be installed on the desktop. There are free ssh clients available for
+other desktops (eg,
+[PuTTY](https://www.chiark.greenend.org.uk/~sgtatham/putty/)). Use the
+ssh utility to connect to the Raspberry Pi (ssh pi@octopi -- password
+is "raspberry") and run the following commands:
 
 ```
 git clone https://github.com/KevinOConnor/klipper
-cd klipper/
+./klipper/scripts/install-octopi.sh
 ```
 
-To compile the micro-controller code, start by configuring it:
+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 running these commands
+on the Raspberry Pi:
 
 ```
+cd ~/klipper/
 make menuconfig
 ```
 
-Select the appropriate micro-controller and serial baud rate. Once
-configured, run:
+Select the appropriate micro-controller and review any other options
+provided. For boards with serial ports, the default baud rate is
+250000 (see the [FAQ](FAQ.md#how-do-i-change-the-serial-baud-rate) if
+changing). Once 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
-------------------------------------
+When flashing for the first time, make sure that OctoPrint is not
+connected directly to the printer (from the OctoPrint web page, under
+the "Connection" section, click "Disconnect"). The most common
+communication device is **/dev/ttyACM0** - see the
+[FAQ](FAQ.md#wheres-my-serial-port) for other possibilities.
 
-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
+Configuring OctoPrint to use Klipper
 ====================================
 
-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:
-
-```
-cp ~/klipper/config/example.cfg ~/printer.cfg
-nano printer.cfg
-```
-
-Make sure to look at and update each setting that is appropriate for
-the hardware.
-
-Configuring OctoPrint to use Klippy
-===================================
-
 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 +84,75 @@ 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 - that means OctoPrint is successfully communicating with
+Klipper. Proceed to the next section.
 
-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.
+Configuring Klipper
+===================
+
+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.
+
+Arguably the easiest way to update the Klipper configuration file is
+to use a desktop editor that supports editing files over the "scp"
+and/or "sftp" protocols. There are freely available tools that support
+this (eg, Notepad++, WinSCP, and Cyberduck). Use one of the example
+config files as a starting point and save it as a file named
+"printer.cfg" in the home directory of the pi user (ie,
+/home/pi/printer.cfg).
+
+Alternatively, one can also copy and edit the file directly on the
+Raspberry Pi via ssh - for example:
+
+```
+cp ~/klipper/config/example.cfg ~/printer.cfg
+nano ~/printer.cfg
+```
+
+Make sure to review and update each setting that is appropriate for
+the hardware.
+
+After creating and editing the file it will be necessary to issue a
+"restart" command in the OctoPrint web 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.
+
+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.
+
+After Klipper reports that the "printer is ready" go on to the
+[config check document](Config_checks.md) to perform some basic checks
+on the pin definitions in the config file.
+
+Contacting the developers
+=========================
+
+Be sure to see the [FAQ](FAQ.md) for answers to some common questions.
+See the [contact page](Contact.md) to report a bug or to contact the
+developers.

docs/Kinematics.md

@@ -0,0 +1,298 @@
+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 limit acceleration so that the stepper motors
+do not skip or put excessive stress on the machine. Klipper limits the
+torque on each stepper by virtue of limiting the acceleration of the
+print head. Enforcing acceleration at the print head naturally also
+limits the torque of the steppers that move the 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 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
+passes near that stepper's tower. Although these moves could require a
+stepper motor acceleration greater than the printer's maximum
+configured move acceleration, the effective mass moved by that stepper
+would be smaller. Thus the higher stepper acceleration does not result
+in significantly higher stepper torque and it is therefore considered
+harmless.
+
+However, to avoid extreme cases, Klipper enforces a maximum ceiling on
+stepper acceleration of three times the printer's configured maximum
+move acceleration. (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 +1,285 @@
+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 developers interested in understanding
+the low-level micro-controller 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.
+
+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.
+
+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=%hu` : 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 value=%c 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
+  '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 to
+  'default_value'. 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 value=%hu
+  default_value=%hu 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 value=%c
+  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=%hu` : 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=%hu` : 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 sample_ticks=%u sample_count=%c
+  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 (and it continues to match for 'sample_count'
+  additional samples spread 'sample_ticks' apart) 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 +1,41 @@
-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. See
+[config checks](Config_checks.md) for a guide to verify basic pin
+settings in the config file.
+
+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 [FAQ](FAQ.md) answers
+some common questions. The [G-Codes](G-Codes.md) document lists
+currently supported run-time commands.
+
+The history of Klipper releases is available at
+[releases](Releases.md). See [contact](Contact.md) for information on
+bug reporting and general communication with the developers.
+
+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 the
+[contributing](CONTRIBUTING.md) document to submit improvements to Klipper.
 
-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 +1,97 @@
+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.
+
+Prerequisites
+=============
+
+In order to tune the pressure advance setting the printer must be
+configured and operational. The tuning test involves printing objects
+and inspecting the differences between objects. In particular, the
+extruder
+[E steps](http://reprap.org/wiki/Triffid_Hunter%27s_Calibration_Guide#E_steps)
+and
+[nozzle temperature](http://reprap.org/wiki/Triffid_Hunter%27s_Calibration_Guide#Nozzle_Temperature)
+should be tuned prior to tuning pressure advance.
+
+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). If there is no significant
+improvement seen after increasing pressure_advance to 0.20, then
+pressure advance is unlikely to improve the quality of prints. Return
+to a default configuration with pressure_advance disabled.
+
+It is not unusual for one corner of the test print to be consistently
+different than the other three corners. This typically occurs when the
+slicer arranges to always change Z height at that corner.  If this
+occurs, then ignore that corner and tune pressure_advance using the
+other three corners.
+
+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 +1,77 @@
 History of Klipper releases. Please see
 [installation](Installation.md) for information on installing Klipper.
 
+Klipper 0.6.0
+=============
+
+Available on 20180331. Major changes in this release:
+* Enhanced heater and thermistor hardware failure checks
+* Support for Z probes
+* Initial support for automatic parameter calibration on deltas (via a
+  new delta_calibrate command)
+* Initial support for bed tilt compensation (via bed_tilt_calibrate
+  command)
+* Initial support for "safe homing" and homing overrides
+* Initial support for displaying status on RepRapDiscount style 2004
+  and 12864 displays
+* New multi-extruder improvements:
+  * Support for shared heaters
+  * Initial support for dual carriages
+* Support for configuring multiple steppers per axis (eg, dual Z)
+* Support for custom digital and pwm output pins (with a new SET_PIN command)
+* Initial support for a "virtual sdcard" that allows printing directly
+  from Klipper (helps on machines too slow to run OctoPrint well)
+* Support for setting different arm lengths on each tower of a delta
+* Support for G-Code M220/M221 commands (speed factor override /
+  extrude factor override)
+* Several documentation updates:
+  * Many new example config files for common off-the-shelf printers
+  * New multiple MCU config example
+  * New bltouch sensor config example
+  * New FAQ, config check, and G-Code documents
+* Initial support for continuous integration testing on all github commits
+* Several bug fixes and code cleanups
+
+Klipper 0.5.0
+=============
+
+Available on 20171025. Major changes in this release:
+
+* Support for printers with multiple extruders.
+* Initial support for running on the Beaglebone PRU. Initial support
+  for the Replicape board.
+* Initial support for running the micro-controller code in a real-time
+  Linux process.
+* Support for multiple micro-controllers. (For example, one could
+  control an extruder with one micro-controller and the rest of the
+  printer with another.) Software clock synchronization is implemented
+  to coordinate actions between micro-controllers.
+* Stepper performance improvements (20Mhz AVRs up to 189K steps per
+  second).
+* Support for controlling servos and support for defining nozzle
+  cooling fans.
+* Several bug fixes and code cleanups
+
+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
@@ -57,50 +44,28 @@ Safety features
    endstop detection is a good idea because of spurious signals caused
    by electrical noise.)
 
-* Support validating that heaters are heating at expected rates. This
-  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
 =============
 
-* Document and test running the host software on a Beagle Bone Black.
-
 * 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:
- * Beagle Bone Black PRU
+* Port to additional micro-controller architectures:
  * Smoothieboard / NXP LPC1769 (ARM cortex-M3)
- * Unix based scheduling; Unix based real-time scheduling
 
-* Support for additional kinematics: scara, corexy, etc.
-
-* Support shared motor enable GPIO lines.
-
-* Support for multiple extruders.
-
-* Support for bed-level probes.
+* Support for additional kinematics: scara, etc.
 
 * Possible support for touch panels attached to the micro-controller.
   (In general, it would be preferable to attach touch panels to the
@@ -108,19 +73,9 @@ 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
 =============
 
-* Possibly use cubic functions instead of quadratic functions in step
-  compression code.
-
 * Possibly support a "feed forward PID" that takes into account the
   amount of plastic being extruded. If the extrude rate changes
   significantly during a print it can cause heating bumps that the PID

docs/beaglebone.md

@@ -0,0 +1,103 @@
+This document describes the process of running Klipper on a Beaglebone
+PRU.
+
+Building an OS image
+====================
+
+Start by installing the
+[latest Jessie IoT](https://beagleboard.org/latest-images) image
+(2017-03-19 or later). One may run the image from either a micro-SD
+card or from builtin eMMC. If using the eMMC, install it to eMMC now
+by following the instructions from the above link.
+
+Then ssh into the beaglebone machine (ssh debian@beaglebone --
+password is "temppwd") and install Klipper by running the following
+commands:
+```
+git clone https://github.com/KevinOConnor/klipper
+./klipper/scripts/install-beaglebone.sh
+```
+
+Install Octoprint
+=================
+
+One may then install Octoprint:
+```
+git clone https://github.com/foosel/OctoPrint.git
+cd OctoPrint/
+virtualenv venv
+./venv/bin/python setup.py install
+```
+
+And setup OctoPrint to start at bootup:
+```
+sudo cp ~/OctoPrint/scripts/octoprint.init /etc/init.d/octoprint
+sudo chmod +x /etc/init.d/octoprint
+sudo cp ~/OctoPrint/scripts/octoprint.default /etc/default/octoprint
+sudo update-rc.d octoprint defaults
+```
+
+It is necessary to modify OctoPrint's **/etc/default/octoprint**
+configuration file. One must change the OCTOPRINT_USER user to
+"debian", change NICELEVEL to 0, uncomment the BASEDIR, CONFIGFILE,
+and DAEMON settings and change the references from "/home/pi/" to
+"/home/debian/":
+```
+sudo nano /etc/default/octoprint
+```
+
+Then start the Octoprint service:
+```
+sudo systemctl start octoprint
+```
+
+Make sure the octoprint web server is accessible - it should be at:
+[http://beaglebone:5000/](http://beaglebone:5000/)
+
+Building the micro-controller code
+==================================
+
+To compile the Klipper micro-controller code, start by configuring it
+for the "Beaglebone PRU":
+```
+cd ~/klipper/
+make menuconfig
+```
+
+To build and install the new micro-controller code, run:
+```
+sudo service klipper stop
+make flash
+sudo service klipper start
+```
+
+For the Replicape, it is also necessary to compile and install the
+micro-controller code for a Linux host process. Run "make menuconfig"
+a second time and configure it for a "Linux process":
+```
+make menuconfig
+```
+
+Then install this micro-controller code as well:
+```
+sudo service klipper stop
+make flash
+sudo service klipper start
+```
+
+Remaining configuration
+=======================
+
+Complete the installation by configuring Klipper and Octoprint
+following the instructions in
+[the main installation document](Installation.md#configuring-klipper).
+
+Printing on the Beaglebone
+==========================
+
+Unfortunately, the Beaglebone processor can sometimes struggle to run
+OctoPrint well. Print stalls have been known to occur on complex
+prints (the printer may move faster than OctoPrint can send movement
+commands). If this occurs, consider using the "virtual_sdcard" feature
+(see [config/example-extras.cfg](../config/example-extras.cfg) for
+details) to print directly from Klipper.

docs/developer-certificate-of-origin

@@ -0,0 +1,37 @@
+Developer Certificate of Origin
+Version 1.1
+
+Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
+1 Letterman Drive
+Suite D4700
+San Francisco, CA, 94129
+
+Everyone is permitted to copy and distribute verbatim copies of this
+license document, but changing it is not allowed.
+
+
+Developer's Certificate of Origin 1.1
+
+By making a contribution to this project, I certify that:
+
+(a) The contribution was created in whole or in part by me and I
+    have the right to submit it under the open source license
+    indicated in the file; or
+
+(b) The contribution is based upon previous work that, to the best
+    of my knowledge, is covered under an appropriate open source
+    license and I have the right under that license to submit that
+    work with modifications, whether created in whole or in part
+    by me, under the same open source license (unless I am
+    permitted to submit under a different license), as indicated
+    in the file; or
+
+(c) The contribution was provided directly to me by some other
+    person who certified (a), (b) or (c) and I have not modified
+    it.
+
+(d) I understand and agree that this project and the contribution
+    are public and that a record of the contribution (including all
+    personal information I submit with it, including my sign-off) is
+    maintained indefinitely and may be redistributed consistent with
+    this project or the open source license(s) involved.

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docs/issue_template.md

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+<!-- Klipper do something undesirable? YOU MUST ATTACH THE KLIPPER LOG FILE.
+See: https://github.com/KevinOConnor/klipper/blob/master/docs/Contact.md -->

docs/prints/square.scad

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+// Test square
+//
+// Generate STL using OpenSCAD:
+//   openscad square.scad -o square.stl
+
+square_width = 5;
+square_size = 60;
+square_height = 5;
+
+module hollow_square() {
+    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]);
+    }
+}
+
+module notch() {
+    CUT = 0.01;
+    depth = .5;
+    width = 1;
+    translate([-depth, -width, -CUT])
+        cube([2*depth, 2*width, square_height + 2*CUT]);
+}
+
+module square_with_notches() {
+    difference() {
+        // Start with initial square
+        hollow_square();
+        // Remove four notches on inside perimeter
+        translate([square_width, square_size/2 - 4, 0])
+            notch();
+        translate([square_size/2, square_size - square_width, 0])
+            rotate([0, 0, 90])
+                notch();
+        translate([square_size - square_width, square_size/2, 0])
+            notch();
+        translate([square_size/2, square_width, 0])
+            rotate([0, 0, 90])
+                notch();
+    }
+}
+
+square_with_notches();

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+      vertex 5 25 0
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+      vertex 5 27 5
+      vertex 5 55 0
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+      vertex 55 29 0
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+      vertex 55 29 5
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+      vertex 55 31 0
+      vertex 55 55 5
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+      vertex 55 31 5
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+      vertex 29 5 5
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+      vertex 29 55 5
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+      vertex 31 55 0
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+      vertex 31 55 5
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+      vertex 55 55 5
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+      vertex 4.5 25 5
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+      vertex 5 27 5
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+      vertex 5 25 0
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+      vertex 4.5 25 5
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+      vertex 29 55.5 0
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+    outer loop
+      vertex 31 55.5 5
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+    outer loop
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+    outer loop
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+  endfacet
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+    outer loop
+      vertex 55.5 29 0
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+  endfacet
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+      vertex 55 31 0
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+    outer loop
+      vertex 55.5 29 0
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+      vertex 55.5 29 5
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+  endfacet
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+    outer loop
+      vertex 55 29 5
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+      vertex 55 29 0
+    endloop
+  endfacet
+  facet normal 0 1 -0
+    outer loop
+      vertex 31 4.5 0
+      vertex 29 4.5 5
+      vertex 31 4.5 5
+    endloop
+  endfacet
+  facet normal 0 1 0
+    outer loop
+      vertex 29 4.5 5
+      vertex 31 4.5 0
+      vertex 29 4.5 0
+    endloop
+  endfacet
+  facet normal -1 0 0
+    outer loop
+      vertex 31 4.5 0
+      vertex 31 5 5
+      vertex 31 5 0
+    endloop
+  endfacet
+  facet normal -1 -0 0
+    outer loop
+      vertex 31 5 5
+      vertex 31 4.5 0
+      vertex 31 4.5 5
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+  endfacet
+  facet normal 1 -0 0
+    outer loop
+      vertex 29 4.5 5
+      vertex 29 5 0
+      vertex 29 5 5
+    endloop
+  endfacet
+  facet normal 1 0 0
+    outer loop
+      vertex 29 5 0
+      vertex 29 4.5 5
+      vertex 29 4.5 0
+    endloop
+  endfacet
+endsolid OpenSCAD_Model

klippy/cartesian.py

@@ -9,72 +9,109 @@ import stepper, homing
 StepList = (0, 1, 2)
 
 class CartKinematics:
-    def __init__(self, printer, config):
-        self.steppers = [stepper.PrinterStepper(
-            printer, config.getsection('stepper_' + n), n)
+    def __init__(self, toolhead, printer, config):
+        self.printer = printer
+        self.steppers = [stepper.LookupMultiHomingStepper(
+            printer, config.getsection('stepper_' + 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)
+        max_velocity, max_accel = toolhead.get_max_velocity()
+        self.max_z_velocity = config.getfloat(
+            'max_z_velocity', max_velocity, above=0., maxval=max_velocity)
+        self.max_z_accel = config.getfloat(
+            'max_z_accel', max_accel, above=0., maxval=max_accel)
         self.need_motor_enable = True
         self.limits = [(1.0, -1.0)] * 3
-    def set_max_jerk(self, max_xy_halt_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):
+        # Setup stepper max halt velocity
+        max_halt_velocity = toolhead.get_max_axis_halt()
+        self.steppers[0].set_max_jerk(max_halt_velocity, max_accel)
+        self.steppers[1].set_max_jerk(max_halt_velocity, max_accel)
+        self.steppers[2].set_max_jerk(
+            min(max_halt_velocity, self.max_z_velocity), max_accel)
+        # Check for dual carriage support
+        self.dual_carriage_axis = None
+        self.dual_carriage_steppers = []
+        if config.has_section('dual_carriage'):
+            dc_config = config.getsection('dual_carriage')
+            self.dual_carriage_axis = dc_config.getchoice(
+                'axis', {'x': 0, 'y': 1})
+            dc_stepper = stepper.LookupMultiHomingStepper(printer, dc_config)
+            dc_stepper.set_max_jerk(max_halt_velocity, max_accel)
+            self.dual_carriage_steppers = [
+                self.steppers[self.dual_carriage_axis], dc_stepper]
+            printer.lookup_object('gcode').register_command(
+                'SET_DUAL_CARRIAGE', self.cmd_SET_DUAL_CARRIAGE,
+                desc=self.cmd_SET_DUAL_CARRIAGE_help)
+    def get_steppers(self, flags=""):
+        if flags == "Z":
+            return [self.steppers[2]]
+        return list(self.steppers)
+    def get_position(self):
+        return [s.mcu_stepper.get_commanded_position() for s in self.steppers]
+    def set_position(self, newpos, homing_axes):
         for i in StepList:
             s = self.steppers[i]
-            s.mcu_stepper.set_position(int(newpos[i]*s.inv_step_dist + 0.5))
+            s.set_position(newpos[i])
+            if i in homing_axes:
+                self.limits[i] = (s.position_min, s.position_max)
+    def _home_axis(self, homing_state, axis, stepper):
+        s = stepper
+        # 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
+        homing_speed = s.homing_speed
+        if axis == 2:
+            homing_speed = min(homing_speed, self.max_z_velocity)
+        homepos = [None, None, None, None]
+        homepos[axis] = s.position_endstop
+        coord = [None, None, None, None]
+        coord[axis] = pos
+        homing_state.home(coord, homepos, s.get_endstops(), homing_speed)
+        # Retract
+        coord[axis] = rpos
+        homing_state.retract(coord, homing_speed)
+        # Home again
+        coord[axis] = r2pos
+        homing_state.home(coord, homepos, s.get_endstops(),
+                          homing_speed/2.0, second_home=True)
+        # Set final homed position
+        coord[axis] = s.position_endstop + s.get_homed_offset()
+        homing_state.set_homed_position(coord)
     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
+            if axis == self.dual_carriage_axis:
+                dc1, dc2 = self.dual_carriage_steppers
+                altc = self.steppers[axis] == dc2
+                self._activate_carriage(0)
+                self._home_axis(homing_state, axis, dc1)
+                self._activate_carriage(1)
+                self._home_axis(homing_state, axis, dc2)
+                self._activate_carriage(altc)
             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)
-            # Set final homed position
-            coord[axis] = s.position_endstop + s.get_homed_offset()*s.step_dist
-            homing_state.set_homed_position(coord)
-    def motor_off(self, move_time):
+                self._home_axis(homing_state, axis, self.steppers[axis])
+    def motor_off(self, print_time):
         self.limits = [(1.0, -1.0)] * 3
         for stepper in self.steppers:
-            stepper.motor_enable(move_time, 0)
+            stepper.motor_enable(print_time, 0)
+        for stepper in self.dual_carriage_steppers:
+            stepper.motor_enable(print_time, 0)
         self.need_motor_enable = True
-    def _check_motor_enable(self, move_time, move):
+    def _check_motor_enable(self, print_time, move):
         need_motor_enable = False
         for i in StepList:
             if move.axes_d[i]:
-                self.steppers[i].motor_enable(move_time, 1)
+                self.steppers[i].motor_enable(print_time, 1)
             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:
@@ -99,49 +136,55 @@ class CartKinematics:
         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):
+    def move(self, print_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
+            self._check_motor_enable(print_time, move)
         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)
+            step_const = self.steppers[i].step_const
+            move_time = print_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
-            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
-                mcu_time += move.accel_t
+                accel_d = move.accel_r * axis_d
+                step_const(move_time, start_pos, accel_d,
+                           move.start_v * axis_r, accel)
+                start_pos += accel_d
+                move_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
-                mcu_time += move.cruise_t
+                cruise_d = move.cruise_r * axis_d
+                step_const(move_time, start_pos, cruise_d, cruise_v, 0.)
+                start_pos += cruise_d
+                move_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
+                step_const(move_time, start_pos, decel_d, cruise_v, -accel)
+    # Dual carriage support
+    def _activate_carriage(self, carriage):
+        toolhead = self.printer.lookup_object('toolhead')
+        toolhead.get_last_move_time()
+        dc_stepper = self.dual_carriage_steppers[carriage]
+        dc_axis = self.dual_carriage_axis
+        self.steppers[dc_axis] = dc_stepper
+        extruder_pos = toolhead.get_position()[3]
+        toolhead.set_position(self.get_position() + [extruder_pos])
+        if self.limits[dc_axis][0] <= self.limits[dc_axis][1]:
+            self.limits[dc_axis] = (
+                dc_stepper.position_min, dc_stepper.position_max)
+        self.need_motor_enable = True
+    cmd_SET_DUAL_CARRIAGE_help = "Set which carriage is active"
+    def cmd_SET_DUAL_CARRIAGE(self, params):
+        gcode = self.printer.lookup_object('gcode')
+        carriage = gcode.get_int('CARRIAGE', params)
+        if carriage not in (0, 1):
+            raise gcode.error("Invalid carriage")
+        self._activate_carriage(carriage)
+        gcode.reset_last_position()

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 +21,24 @@ 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);
+
+    int32_t 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);
+    void steppersync_set_time(struct steppersync *ss
+        , double time_offset, double mcu_freq);
+    int steppersync_flush(struct steppersync *ss, uint64_t move_clock);
 """
 
 defs_serialqueue = """
@@ -63,9 +61,8 @@ defs_serialqueue = """
         , uint64_t min_clock, uint64_t req_clock);
     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_set_clock_est(struct serialqueue *sq, double est_freq
+        , double last_clock_time, uint64_t last_clock);
     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 +70,7 @@ 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 +86,14 @@ 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 +104,8 @@ 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 +118,20 @@ 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/clocksync.py

@@ -0,0 +1,219 @@
+# Micro-controller clock synchronization
+#
+# 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, math
+
+COMM_TIMEOUT = 3.5
+RTT_AGE = .000010 / (60. * 60.)
+DECAY = 1. / 30.
+TRANSMIT_EXTRA = .001
+
+class ClockSync:
+    def __init__(self, reactor):
+        self.reactor = reactor
+        self.serial = None
+        self.status_timer = self.reactor.register_timer(self._status_event)
+        self.status_cmd = None
+        self.mcu_freq = 1.
+        self.last_clock = 0
+        self.clock_est = (0., 0., 0.)
+        # Minimum round-trip-time tracking
+        self.min_half_rtt = 999999999.9
+        self.min_rtt_time = 0.
+        # Linear regression of mcu clock and system sent_time
+        self.time_avg = self.time_variance = 0.
+        self.clock_avg = self.clock_covariance = 0.
+        self.prediction_variance = 0.
+        self.last_prediction_time = 0.
+    def connect(self, serial):
+        self.serial = serial
+        self.mcu_freq = serial.msgparser.get_constant_float('CLOCK_FREQ')
+        # Load initial clock and frequency
+        get_uptime_cmd = serial.lookup_command('get_uptime')
+        params = get_uptime_cmd.send_with_response(response='uptime')
+        self.last_clock = (params['high'] << 32) | params['clock']
+        self.clock_avg = self.last_clock
+        self.time_avg = params['#sent_time']
+        self.clock_est = (self.time_avg, self.clock_avg, self.mcu_freq)
+        self.prediction_variance = (.001 * self.mcu_freq)**2
+        # Enable periodic get_status timer
+        self.status_cmd = serial.lookup_command('get_status')
+        for i in range(8):
+            params = self.status_cmd.send_with_response(response='status')
+            self._handle_status(params)
+            self.reactor.pause(0.100)
+        serial.register_callback(self._handle_status, 'status')
+        self.reactor.update_timer(self.status_timer, self.reactor.NOW)
+    def connect_file(self, serial, pace=False):
+        self.serial = serial
+        self.mcu_freq = serial.msgparser.get_constant_float('CLOCK_FREQ')
+        self.clock_est = (0., 0., self.mcu_freq)
+        freq = 1000000000000.
+        if pace:
+            freq = self.mcu_freq
+        serial.set_clock_est(freq, self.reactor.monotonic(), 0)
+    # MCU clock querying (status callback invoked from background thread)
+    def _status_event(self, eventtime):
+        self.status_cmd.send()
+        return eventtime + 1.0
+    def _handle_status(self, params):
+        # Extend clock to 64bit
+        last_clock = self.last_clock
+        clock = (last_clock & ~0xffffffff) | params['clock']
+        if clock < last_clock:
+            clock += 0x100000000
+        self.last_clock = clock
+        # Check if this is the best round-trip-time seen so far
+        sent_time = params['#sent_time']
+        if not sent_time:
+            return
+        receive_time = params['#receive_time']
+        half_rtt = .5 * (receive_time - sent_time)
+        aged_rtt = (sent_time - self.min_rtt_time) * RTT_AGE
+        if half_rtt < self.min_half_rtt + aged_rtt:
+            self.min_half_rtt = half_rtt
+            self.min_rtt_time = sent_time
+            logging.debug("new minimum rtt %.3f: hrtt=%.6f freq=%d",
+                          sent_time, half_rtt, self.clock_est[2])
+        # Filter out samples that are extreme outliers
+        exp_clock = ((sent_time - self.time_avg) * self.clock_est[2]
+                     + self.clock_avg)
+        clock_diff2 = (clock - exp_clock)**2
+        if (clock_diff2 > 25. * self.prediction_variance
+            and clock_diff2 > (.000500 * self.mcu_freq)**2):
+            if clock > exp_clock and sent_time < self.last_prediction_time + 10.:
+                logging.debug("Ignoring clock sample %.3f:"
+                              " freq=%d diff=%d stddev=%.3f",
+                              sent_time, self.clock_est[2], clock - exp_clock,
+                              math.sqrt(self.prediction_variance))
+                return
+            logging.info("Resetting prediction variance %.3f:"
+                         " freq=%d diff=%d stddev=%.3f",
+                         sent_time, self.clock_est[2], clock - exp_clock,
+                         math.sqrt(self.prediction_variance))
+            self.prediction_variance = (.001 * self.mcu_freq)**2
+        else:
+            self.last_prediction_time = sent_time
+            self.prediction_variance = (
+                (1. - DECAY) * (self.prediction_variance + clock_diff2 * DECAY))
+        # Add clock and sent_time to linear regression
+        diff_sent_time = sent_time - self.time_avg
+        self.time_avg += DECAY * diff_sent_time
+        self.time_variance = (1. - DECAY) * (
+            self.time_variance + diff_sent_time**2 * DECAY)
+        diff_clock = clock - self.clock_avg
+        self.clock_avg += DECAY * diff_clock
+        self.clock_covariance = (1. - DECAY) * (
+            self.clock_covariance + diff_sent_time * diff_clock * DECAY)
+        # Update prediction from linear regression
+        new_freq = self.clock_covariance / self.time_variance
+        pred_stddev = math.sqrt(self.prediction_variance)
+        self.serial.set_clock_est(new_freq, self.time_avg + TRANSMIT_EXTRA,
+                                  int(self.clock_avg - 3. * pred_stddev))
+        self.clock_est = (self.time_avg + self.min_half_rtt,
+                          self.clock_avg, new_freq)
+        #logging.debug("regr %.3f: freq=%.3f d=%d(%.3f)",
+        #              sent_time, new_freq, clock - exp_clock, pred_stddev)
+    # clock frequency conversions
+    def print_time_to_clock(self, print_time):
+        return int(print_time * self.mcu_freq)
+    def clock_to_print_time(self, clock):
+        return clock / self.mcu_freq
+    def get_adjusted_freq(self):
+        return self.mcu_freq
+    # system time conversions
+    def get_clock(self, eventtime):
+        sample_time, clock, freq = self.clock_est
+        return int(clock + (eventtime - sample_time) * freq)
+    def estimated_print_time(self, eventtime):
+        return self.clock_to_print_time(self.get_clock(eventtime))
+    # misc commands
+    def clock32_to_clock64(self, clock32):
+        last_clock = self.last_clock
+        clock_diff = (last_clock - clock32) & 0xffffffff
+        if clock_diff & 0x80000000:
+            return last_clock + 0x100000000 - clock_diff
+        return last_clock - clock_diff
+    def is_active(self, eventtime):
+        print_time = self.estimated_print_time(eventtime)
+        last_clock_print_time = self.clock_to_print_time(self.last_clock)
+        return print_time < last_clock_print_time + COMM_TIMEOUT
+    def dump_debug(self):
+        sample_time, clock, freq = self.clock_est
+        return ("clocksync state: mcu_freq=%d last_clock=%d"
+                " clock_est=(%.3f %d %.3f) min_half_rtt=%.6f min_rtt_time=%.3f"
+                " time_avg=%.3f(%.3f) clock_avg=%.3f(%.3f)"
+                " pred_variance=%.3f" % (
+                    self.mcu_freq, self.last_clock, sample_time, clock, freq,
+                    self.min_half_rtt, self.min_rtt_time,
+                    self.time_avg, self.time_variance,
+                    self.clock_avg, self.clock_covariance,
+                    self.prediction_variance))
+    def stats(self, eventtime):
+        sample_time, clock, freq = self.clock_est
+        return "freq=%d" % (freq,)
+    def calibrate_clock(self, print_time, eventtime):
+        return (0., self.mcu_freq)
+
+# Clock syncing code for secondary MCUs (whose clocks are sync'ed to a
+# primary MCU)
+class SecondarySync(ClockSync):
+    def __init__(self, reactor, main_sync):
+        ClockSync.__init__(self, reactor)
+        self.main_sync = main_sync
+        self.clock_adj = (0., 1.)
+        self.last_sync_time = 0.
+    def connect(self, serial):
+        ClockSync.connect(self, serial)
+        self.clock_adj = (0., self.mcu_freq)
+        curtime = self.reactor.monotonic()
+        main_print_time = self.main_sync.estimated_print_time(curtime)
+        local_print_time = self.estimated_print_time(curtime)
+        self.clock_adj = (main_print_time - local_print_time, self.mcu_freq)
+        self.calibrate_clock(0., curtime)
+    def connect_file(self, serial, pace=False):
+        ClockSync.connect_file(self, serial, pace)
+        self.clock_adj = (0., self.mcu_freq)
+    # clock frequency conversions
+    def print_time_to_clock(self, print_time):
+        adjusted_offset, adjusted_freq = self.clock_adj
+        return int((print_time - adjusted_offset) * adjusted_freq)
+    def clock_to_print_time(self, clock):
+        adjusted_offset, adjusted_freq = self.clock_adj
+        return clock / adjusted_freq + adjusted_offset
+    def get_adjusted_freq(self):
+        adjusted_offset, adjusted_freq = self.clock_adj
+        return adjusted_freq
+    # misc commands
+    def dump_debug(self):
+        adjusted_offset, adjusted_freq = self.clock_adj
+        return "%s clock_adj=(%.3f %.3f)" % (
+            ClockSync.dump_debug(self), adjusted_offset, adjusted_freq)
+    def stats(self, eventtime):
+        adjusted_offset, adjusted_freq = self.clock_adj
+        return "%s adj=%d" % (ClockSync.stats(self, eventtime), adjusted_freq)
+    def calibrate_clock(self, print_time, eventtime):
+        # Calculate: est_print_time = main_sync.estimatated_print_time()
+        ser_time, ser_clock, ser_freq = self.main_sync.clock_est
+        main_mcu_freq = self.main_sync.mcu_freq
+        est_main_clock = (eventtime - ser_time) * ser_freq + ser_clock
+        est_print_time = est_main_clock / main_mcu_freq
+        # Determine sync1_print_time and sync2_print_time
+        sync1_print_time = max(print_time, est_print_time)
+        sync2_print_time = max(sync1_print_time + 4., self.last_sync_time,
+                               print_time + 2.5 * (print_time - est_print_time))
+        # Calc sync2_sys_time (inverse of main_sync.estimatated_print_time)
+        sync2_main_clock = sync2_print_time * main_mcu_freq
+        sync2_sys_time = ser_time + (sync2_main_clock - ser_clock) / ser_freq
+        # Adjust freq so estimated print_time will match at sync2_print_time
+        sync1_clock = self.print_time_to_clock(sync1_print_time)
+        sync2_clock = self.get_clock(sync2_sys_time)
+        adjusted_freq = ((sync2_clock - sync1_clock)
+                         / (sync2_print_time - sync1_print_time))
+        adjusted_offset = sync1_print_time - sync1_clock / adjusted_freq
+        # Apply new values
+        self.clock_adj = (adjusted_offset, adjusted_freq)
+        self.last_sync_time = sync2_print_time
+        return self.clock_adj

klippy/console.py

@@ -1,12 +1,31 @@
-#!/usr/bin/env python
+#!/usr/bin/env python2
 # 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
+import reactor, serialhdl, pins, util, msgproto, clocksync
 
-import reactor, serialhdl, pins, util, msgproto
+help_txt = """
+  This is a debugging console for the Klipper micro-controller.
+  In addition to mcu commands, the following artificial commands are
+  available:
+    PINS  : Load pin name aliases (eg, "PINS arduino")
+    DELAY : Send a command at a clock time (eg, "DELAY 9999 get_uptime")
+    FLOOD : Send a command many times (eg, "FLOOD 22 .01 get_uptime")
+    SUPPRESS : Suppress a response message (eg, "SUPPRESS stats")
+    SET   : Create a local variable (eg, "SET myvar 123.4")
+    STATS : Report serial statistics
+    LIST  : List available mcu commands, local commands, and local variables
+    HELP  : Show this text
+  All commands also support evaluation by enclosing an expression in { }.
+  For example, "reset_step_clock oid=4 clock={clock + freq}".  In addition
+  to user defined variables (via the SET command) the following builtin
+  variables may be used in expressions:
+    clock : The current mcu clock time (as estimated by the host)
+    freq  : The mcu clock frequency
+"""
 
 re_eval = re.compile(r'\{(?P<eval>[^}]*)\}')
 
@@ -14,71 +33,137 @@ class KeyboardReader:
     def __init__(self, ser, reactor):
         self.ser = ser
         self.reactor = reactor
+        self.clocksync = clocksync.ClockSync(self.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)
         self.connect_timer = reactor.register_timer(self.connect, reactor.NOW)
-        self.local_commands = { "PINS": self.set_pin_map, "SET": self.set_var }
+        self.local_commands = {
+            "PINS": self.command_PINS, "SET": self.command_SET,
+            "DELAY": self.command_DELAY, "FLOOD": self.command_FLOOD,
+            "SUPPRESS": self.command_SUPPRESS, "STATS": self.command_STATS,
+            "LIST": self.command_LIST, "HELP": self.command_HELP,
+        }
         self.eval_globals = {}
     def connect(self, eventtime):
+        self.output(help_txt)
+        self.output("="*20 + " attempting to connect " + "="*20)
         self.ser.connect()
+        self.clocksync.connect(self.ser)
+        self.ser.handle_default = self.handle_default
+        self.mcu_freq = self.ser.msgparser.get_constant_float('CLOCK_FREQ')
+        mcu_type = self.ser.msgparser.get_constant('MCU')
+        self.pins = pins.PinResolver(mcu_type, validate_aliases=False)
         self.reactor.unregister_timer(self.connect_timer)
+        self.output("="*20 + "       connected       " + "="*20)
         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 handle_suppress(self, params):
+        pass
     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)
-    def set_pin_map(self, parts):
-        mcu = self.ser.msgparser.config['MCU']
-        self.pins = pins.map_pins(parts[1], mcu)
-    def set_var(self, parts):
+        self.eval_globals['freq'] = self.mcu_freq
+        self.eval_globals['clock'] = self.clocksync.get_clock(eventtime)
+    def command_PINS(self, parts):
+        self.pins.update_aliases(parts[1])
+    def command_SET(self, parts):
         val = parts[2]
         try:
-            val = int(val)
+            val = float(val)
         except ValueError:
-            try:
-                val = float(val)
-            except ValueError:
-                pass
+            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 command_DELAY(self, parts):
+        try:
+            val = int(parts[1])
+        except ValueError as e:
+            self.output("Error: %s" % (str(e),))
+            return
+        try:
+            self.ser.send(' '.join(parts[2:]), minclock=val)
+        except msgproto.error as e:
+            self.output("Error: %s" % (str(e),))
+            return
+    def command_FLOOD(self, parts):
+        try:
+            count = int(parts[1])
+            delay = float(parts[2])
+        except ValueError as e:
+            self.output("Error: %s" % (str(e),))
+            return
+        msg = ' '.join(parts[3:])
+        delay_clock = int(delay * self.mcu_freq)
+        msg_clock = int(self.clocksync.get_clock(self.reactor.monotonic())
+                        + self.mcu_freq * .200)
+        try:
+            for i in range(count):
+                next_clock = msg_clock + delay_clock
+                self.ser.send(msg, minclock=msg_clock, reqclock=next_clock)
+                msg_clock = next_clock
+        except msgproto.error as e:
+            self.output("Error: %s" % (str(e),))
+            return
+    def command_SUPPRESS(self, parts):
+        oid = None
+        try:
+            name = parts[1]
+            if len(parts) > 2:
+                oid = int(parts[2])
+        except ValueError as e:
+            self.output("Error: %s" % (str(e),))
+            return
+        self.ser.register_callback(self.handle_suppress, name, oid)
+    def command_STATS(self, parts):
+        curtime = self.reactor.monotonic()
+        self.output(' '.join([self.ser.stats(curtime),
+                              self.clocksync.stats(curtime)]))
+    def command_LIST(self, parts):
+        self.update_evals(self.reactor.monotonic())
+        mp = self.ser.msgparser
+        out = "Available mcu commands:"
+        out += "\n  ".join([""] + sorted([
+            mp.messages_by_id[i].msgformat for i in mp.command_ids]))
+        out += "\nAvailable artificial commands:"
+        out += "\n  ".join([""] + [n for n in sorted(self.local_commands)])
+        out += "\nAvailable local variables:"
+        out += "\n  ".join([""] + ["%s: %s" % (k, v)
+                                   for k, v in sorted(self.eval_globals.items())])
+        self.output(out)
+    def command_HELP(self, parts):
+        self.output(help_txt)
     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], dict(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 = self.pins.update_command(line).strip()
             except:
-                print "Unable to map pin: ", line
+                self.output("Unable to map pin: %s" % (line,))
                 return None
         if line:
             parts = line.split()
             if parts[0] in self.local_commands:
                 self.local_commands[parts[0]](parts)
                 return None
-        try:
-            msg = self.ser.msgparser.create_command(line)
-        except msgproto.error, e:
-            print "Error:", e
-            return None
-        return msg
+        return line
     def process_kbd(self, eventtime):
         self.data += os.read(self.fd, 4096)
 
@@ -93,7 +178,11 @@ class KeyboardReader:
             msg = self.translate(line.strip(), eventtime)
             if msg is None:
                 continue
-            self.ser.send(msg)
+            try:
+                self.ser.send(msg)
+            except msgproto.error as e:
+                self.output("Error: %s" % (str(e),))
+                return None
         self.data = kbdlines[-1]
 
 def main():

klippy/corexy.py

@@ -0,0 +1,161 @@
+# 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, math
+import stepper, homing
+
+StepList = (0, 1, 2)
+
+class CoreXYKinematics:
+    def __init__(self, toolhead, printer, config):
+        self.steppers = [
+            stepper.PrinterHomingStepper(
+                printer, config.getsection('stepper_x')),
+            stepper.PrinterHomingStepper(
+                printer, config.getsection('stepper_y')),
+            stepper.LookupMultiHomingStepper(
+                printer, config.getsection('stepper_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)
+        max_velocity, max_accel = toolhead.get_max_velocity()
+        self.max_z_velocity = config.getfloat(
+            'max_z_velocity', max_velocity, above=0., maxval=max_velocity)
+        self.max_z_accel = config.getfloat(
+            'max_z_accel', max_accel, above=0., maxval=max_accel)
+        self.need_motor_enable = True
+        self.limits = [(1.0, -1.0)] * 3
+        # Setup stepper max halt velocity
+        max_halt_velocity = toolhead.get_max_axis_halt()
+        max_xy_halt_velocity = max_halt_velocity * math.sqrt(2.)
+        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(
+            min(max_halt_velocity, self.max_z_velocity), self.max_z_accel)
+    def get_steppers(self, flags=""):
+        if flags == "Z":
+            return [self.steppers[2]]
+        return list(self.steppers)
+    def get_position(self):
+        pos = [s.mcu_stepper.get_commanded_position() for s in self.steppers]
+        return [0.5 * (pos[0] + pos[1]), 0.5 * (pos[0] - pos[1]), pos[2]]
+    def set_position(self, newpos, homing_axes):
+        pos = (newpos[0] + newpos[1], newpos[0] - newpos[1], newpos[2])
+        for i in StepList:
+            s = self.steppers[i]
+            s.set_position(pos[i])
+            if i in homing_axes:
+                self.limits[i] = (s.position_min, s.position_max)
+    def home(self, homing_state):
+        # Each axis is homed independently and in order
+        for axis in homing_state.get_axes():
+            s = self.steppers[axis]
+            # 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
+            homing_speed = s.homing_speed
+            if axis == 2:
+                homing_speed = min(homing_speed, self.max_z_velocity)
+            homepos = [None, None, None, None]
+            homepos[axis] = s.position_endstop
+            coord = [None, None, None, None]
+            coord[axis] = pos
+            homing_state.home(coord, homepos, s.get_endstops(), homing_speed)
+            # Retract
+            coord[axis] = rpos
+            homing_state.retract(coord, homing_speed)
+            # Home again
+            coord[axis] = r2pos
+            homing_state.home(coord, homepos, s.get_endstops(),
+                              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, print_time):
+        self.limits = [(1.0, -1.0)] * 3
+        for stepper in self.steppers:
+            stepper.motor_enable(print_time, 0)
+        self.need_motor_enable = True
+    def _check_motor_enable(self, print_time, move):
+        if move.axes_d[0] or move.axes_d[1]:
+            self.steppers[0].motor_enable(print_time, 1)
+            self.steppers[1].motor_enable(print_time, 1)
+        if move.axes_d[2]:
+            self.steppers[2].motor_enable(print_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 _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, print_time, move):
+        if self.need_motor_enable:
+            self._check_motor_enable(print_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
+            step_const = self.steppers[i].step_const
+            move_time = print_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
+                step_const(move_time, start_pos, accel_d,
+                           move.start_v * axis_r, accel)
+                start_pos += accel_d
+                move_time += move.accel_t
+            # Cruising steps
+            if move.cruise_r:
+                cruise_d = move.cruise_r * axis_d
+                step_const(move_time, start_pos, cruise_d, cruise_v, 0.)
+                start_pos += cruise_d
+                move_time += move.cruise_t
+            # Deceleration steps
+            if move.decel_r:
+                decel_d = move.decel_r * axis_d
+                step_const(move_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
@@ -8,234 +8,218 @@ 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.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.arm_length2 = arm_length**2
-        self.max_xy2 = min(radius, arm_length - radius)**2
+    def __init__(self, toolhead, printer, config):
+        stepper_configs = [config.getsection('stepper_' + n)
+                           for n in ['a', 'b', 'c']]
+        stepper_a = stepper.PrinterHomingStepper(printer, stepper_configs[0])
+        stepper_b = stepper.PrinterHomingStepper(
+            printer, stepper_configs[1],
+            default_position=stepper_a.position_endstop)
+        stepper_c = stepper.PrinterHomingStepper(
+            printer, stepper_configs[2],
+            default_position=stepper_a.position_endstop)
+        self.steppers = [stepper_a, stepper_b, stepper_c]
+        self.need_motor_enable = self.need_home = True
+        self.radius = radius = config.getfloat('delta_radius', above=0.)
+        arm_length_a = stepper_configs[0].getfloat('arm_length', above=radius)
+        self.arm_lengths = arm_lengths = [
+            sconfig.getfloat('arm_length', arm_length_a, above=radius)
+            for sconfig in stepper_configs]
+        self.arm2 = [arm**2 for arm in arm_lengths]
+        self.endstops = [s.position_endstop + math.sqrt(arm2 - radius**2)
+                         for s, arm2 in zip(self.steppers, self.arm2)]
         self.limit_xy2 = -1.
-        tower_height_at_zeros = math.sqrt(self.arm_length2 - radius**2)
-        self.max_z = self.steppers[0].position_max
-        self.limit_z = self.max_z - (arm_length - tower_height_at_zeros)
-        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
-        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.])
+        self.max_z = min([s.position_endstop for s in self.steppers])
+        self.min_z = config.getfloat('minimum_z_position', 0, maxval=self.max_z)
+        self.limit_z = min([ep - arm
+                            for ep, arm in zip(self.endstops, arm_lengths)])
+        logging.info(
+            "Delta max build height %.2fmm (radius tapered above %.2fmm)" % (
+                self.max_z, self.limit_z))
+        # Setup stepper max halt velocity
+        self.max_velocity, self.max_accel = toolhead.get_max_velocity()
+        self.max_z_velocity = config.getfloat(
+            'max_z_velocity', self.max_velocity,
+            above=0., maxval=self.max_velocity)
+        max_halt_velocity = toolhead.get_max_axis_halt()
+        for s in self.steppers:
+            s.set_max_jerk(max_halt_velocity, self.max_accel)
+        # Determine tower locations in cartesian space
+        self.angles = [sconfig.getfloat('angle', angle)
+                       for sconfig, angle in zip(stepper_configs,
+                                                 [210., 330., 90.])]
+        self.towers = [(math.cos(math.radians(angle)) * radius,
+                        math.sin(math.radians(angle)) * radius)
+                       for angle in self.angles]
+        # 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
+        min_arm_length = min(arm_lengths)
+        def ratio_to_dist(ratio):
+            return (ratio * math.sqrt(min_arm_length**2 / (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, min_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 get_steppers(self, flags=""):
+        return list(self.steppers)
     def _cartesian_to_actuator(self, coord):
-        return [int((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)
+        return [math.sqrt(self.arm2[i] - (self.towers[i][0] - coord[0])**2
+                          - (self.towers[i][1] - coord[1])**2) + coord[2]
                 for i in StepList]
     def _actuator_to_cartesian(self, pos):
-        # Based on code from Smoothieware
-        tower1 = list(self.towers[0]) + [pos[0]]
-        tower2 = list(self.towers[1]) + [pos[1]]
-        tower3 = list(self.towers[2]) + [pos[2]]
-
-        s12 = matrix_sub(tower1, tower2)
-        s23 = matrix_sub(tower2, tower3)
-        s13 = matrix_sub(tower1, tower3)
-
-        normal = matrix_cross(s12, s23)
-
-        magsq_s12 = matrix_magsq(s12)
-        magsq_s23 = matrix_magsq(s23)
-        magsq_s13 = matrix_magsq(s13)
-
-        inv_nmag_sq = 1.0 / matrix_magsq(normal)
-        q = 0.5 * inv_nmag_sq
-
-        a = q * magsq_s23 * matrix_dot(s12, s13)
-        b = -q * magsq_s13 * matrix_dot(s12, s23) # negate because we use s12 instead of s21
-        c = q * magsq_s12 * matrix_dot(s13, s23)
-
-        circumcenter = [tower1[0] * a + tower2[0] * b + tower3[0] * c,
-                        tower1[1] * a + tower2[1] * b + tower3[1] * c,
-                        tower1[2] * a + tower2[2] * b + tower3[2] * c]
-
-        r_sq = 0.5 * q * magsq_s12 * magsq_s23 * magsq_s13
-        dist = math.sqrt(inv_nmag_sq * (self.arm_length2 - r_sq))
-
-        return matrix_sub(circumcenter, matrix_mul(normal, dist))
-    def set_position(self, newpos):
+        return actuator_to_cartesian(self.towers, self.arm2, pos)
+    def get_position(self):
+        spos = [s.mcu_stepper.get_commanded_position() for s in self.steppers]
+        return self._actuator_to_cartesian(spos)
+    def set_position(self, newpos, homing_axes):
         pos = self._cartesian_to_actuator(newpos)
         for i in StepList:
-            self.steppers[i].mcu_stepper.set_position(pos[i])
+            self.steppers[i].set_position(pos[i])
+        self.limit_xy2 = -1.
+        if tuple(homing_axes) == StepList:
+            self.need_home = False
     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
+        endstops = [es for s in self.steppers for es in s.get_endstops()]
+        s = self.steppers[0] # Assume homing speed same for all steppers
         # Initial homing
-        homepos = [0., 0., s.position_endstop, None]
+        homing_speed = min(s.homing_speed, self.max_z_velocity)
+        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)
+        coord[2] = -1.5 * math.sqrt(max(self.arm2)-self.max_xy2)
+        homing_state.home(coord, homepos, endstops, homing_speed)
         # Retract
         coord[2] = homepos[2] - s.homing_retract_dist
-        homing_state.retract(list(coord), s.homing_speed)
+        homing_state.retract(coord, homing_speed)
         # Home again
         coord[2] -= s.homing_retract_dist
-        homing_state.home(list(coord), homepos, self.steppers
-                          , s.homing_speed/2.0, second_home=True)
+        homing_state.home(coord, homepos, endstops,
+                          homing_speed/2.0, second_home=True)
         # Set final homed position
-        coord = [(s.mcu_stepper.commanded_position + s.get_homed_offset())
-                 * s.step_dist
-                 for s in self.steppers]
-        homing_state.set_homed_position(self._actuator_to_cartesian(coord))
-    def motor_off(self, move_time):
+        spos = [ep + s.get_homed_offset()
+                for ep, s in zip(self.endstops, self.steppers)]
+        homing_state.set_homed_position(self._actuator_to_cartesian(spos))
+    def motor_off(self, print_time):
         self.limit_xy2 = -1.
         for stepper in self.steppers:
-            stepper.motor_enable(move_time, 0)
-        self.need_motor_enable = True
-    def _check_motor_enable(self, move_time):
+            stepper.motor_enable(print_time, 0)
+        self.need_motor_enable = self.need_home = True
+    def _check_motor_enable(self, print_time):
         for i in StepList:
-            self.steppers[i].motor_enable(move_time, 1)
+            self.steppers[i].motor_enable(print_time, 1)
         self.need_motor_enable = False
-    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_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.:
-                raise homing.EndstopMoveError(end_pos, "Must home first")
-            raise homing.EndstopMoveError(end_pos)
+        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")
+        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:
-                raise homing.EndstopMoveError(end_pos)
+            limit_xy2 = min(limit_xy2, (self.max_z - end_pos[2])**2)
+        if xy2 > limit_xy2 or end_pos[2] < self.min_z 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)
-    def move(self, move_time, move):
+            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, print_time, move):
+        if self.need_motor_enable:
+            self._check_motor_enable(print_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.arm2[i] - 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)
+            step_delta = self.steppers[i].step_delta
+            move_time = print_time
+            if accel_d:
+                step_delta(move_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
+                move_time += move.accel_t
+            if cruise_d:
+                step_delta(move_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
+                move_time += move.cruise_t
+            if decel_d:
+                step_delta(move_time, decel_d, cruise_v, -accel,
+                           vt_startz, vt_startxy_d, vt_arm_d, movez_r)
+    # Helper functions for DELTA_CALIBRATE script
+    def get_stable_position(self):
+        return [int((ep - s.mcu_stepper.get_commanded_position())
+                    /  s.mcu_stepper.get_step_dist() + .5)
+                * s.mcu_stepper.get_step_dist()
+                for ep, s in zip(self.endstops, self.steppers)]
+    def get_calibrate_params(self):
+        return {
+            'endstop_a': self.steppers[0].position_endstop,
+            'endstop_b': self.steppers[1].position_endstop,
+            'endstop_c': self.steppers[2].position_endstop,
+            'angle_a': self.angles[0], 'angle_b': self.angles[1],
+            'angle_c': self.angles[2], 'radius': self.radius,
+            'arm_a': self.arm_lengths[0], 'arm_b': self.arm_lengths[1],
+            'arm_c': self.arm_lengths[2] }
 
 
 ######################################################################
@@ -253,8 +237,49 @@ def matrix_dot(m1, m2):
 def matrix_magsq(m1):
     return m1[0]**2 + m1[1]**2 + m1[2]**2
 
+def matrix_add(m1, m2):
+    return [m1[0] + m2[0], m1[1] + m2[1], m1[2] + m2[2]]
+
 def matrix_sub(m1, m2):
     return [m1[0] - m2[0], m1[1] - m2[1], m1[2] - m2[2]]
 
 def matrix_mul(m1, s):
     return [m1[0]*s, m1[1]*s, m1[2]*s]
+
+def actuator_to_cartesian(towers, arm2, pos):
+    # Find nozzle position using trilateration (see wikipedia)
+    carriage1 = list(towers[0]) + [pos[0]]
+    carriage2 = list(towers[1]) + [pos[1]]
+    carriage3 = list(towers[2]) + [pos[2]]
+
+    s21 = matrix_sub(carriage2, carriage1)
+    s31 = matrix_sub(carriage3, carriage1)
+
+    d = math.sqrt(matrix_magsq(s21))
+    ex = matrix_mul(s21, 1. / d)
+    i = matrix_dot(ex, s31)
+    vect_ey = matrix_sub(s31, matrix_mul(ex, i))
+    ey = matrix_mul(vect_ey, 1. / math.sqrt(matrix_magsq(vect_ey)))
+    ez = matrix_cross(ex, ey)
+    j = matrix_dot(ey, s31)
+
+    x = (arm2[0] - arm2[1] + d**2) / (2. * d)
+    y = (arm2[0] - arm2[2] - x**2 + (x-i)**2 + j**2) / (2. * j)
+    z = -math.sqrt(arm2[0] - x**2 - y**2)
+
+    ex_x = matrix_mul(ex, x)
+    ey_y = matrix_mul(ey, y)
+    ez_z = matrix_mul(ez, z)
+    return matrix_add(carriage1, matrix_add(ex_x, matrix_add(ey_y, ez_z)))
+
+def get_position_from_stable(spos, params):
+    angles = [params['angle_a'], params['angle_b'], params['angle_c']]
+    radius = params['radius']
+    radius2 = radius**2
+    towers = [(math.cos(angle) * radius, math.sin(angle) * radius)
+              for angle in map(math.radians, angles)]
+    arm2 = [a**2 for a in [params['arm_a'], params['arm_b'], params['arm_c']]]
+    endstops = [params['endstop_a'], params['endstop_b'], params['endstop_c']]
+    pos = [es + math.sqrt(a2 - radius2) - p
+           for es, a2, p in zip(endstops, arm2, spos)]
+    return actuator_to_cartesian(towers, arm2, pos)

klippy/extras/__init__.py

@@ -0,0 +1,5 @@
+# Package definition for the extras directory
+#
+# Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.

klippy/extras/ad5206.py

@@ -0,0 +1,32 @@
+# AD5206 digipot code
+#
+# Copyright (C) 2017,2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import pins
+
+class ad5206:
+    def __init__(self, config):
+        printer = config.get_printer()
+        enable_pin_params = pins.get_printer_pins(printer).lookup_pin(
+            'digital_out', config.get('enable_pin'))
+        if enable_pin_params['invert']:
+            raise pins.error("ad5206 can not invert pin")
+        self.mcu = enable_pin_params['chip']
+        self.pin = enable_pin_params['pin']
+        self.mcu.add_config_object(self)
+        scale = config.getfloat('scale', 1., above=0.)
+        self.channels = [None] * 6
+        for i in range(len(self.channels)):
+            val = config.getfloat('channel_%d' % (i+1,), None,
+                                  minval=0., maxval=scale)
+            if val is not None:
+                self.channels[i] = int(val * 256. / scale + .5)
+    def build_config(self):
+        for i, val in enumerate(self.channels):
+            if val is not None:
+                self.mcu.add_config_cmd(
+                    "send_spi_message pin=%s msg=%02x%02x" % (self.pin, i, val))
+
+def load_config_prefix(config):
+    return ad5206(config)

klippy/extras/bed_tilt.py

@@ -0,0 +1,113 @@
+# Bed tilt compensation
+#
+# Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import logging
+import probe, mathutil
+
+class BedTilt:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.x_adjust = config.getfloat('x_adjust', 0.)
+        self.y_adjust = config.getfloat('y_adjust', 0.)
+        if config.get('points', None) is not None:
+            BedTiltCalibrate(config, self)
+        self.toolhead = None
+        gcode = self.printer.lookup_object('gcode')
+        gcode.set_move_transform(self)
+    def printer_state(self, state):
+        if state == 'connect':
+            self.toolhead = self.printer.lookup_object('toolhead')
+    def get_position(self):
+        x, y, z, e = self.toolhead.get_position()
+        return [x, y, z - x*self.x_adjust - y*self.y_adjust, e]
+    def move(self, newpos, speed):
+        x, y, z, e = newpos
+        self.toolhead.move([x, y, z + x*self.x_adjust + y*self.y_adjust, e],
+                           speed)
+
+# Helper script to calibrate the bed tilt
+class BedTiltCalibrate:
+    def __init__(self, config, bedtilt):
+        self.bedtilt = bedtilt
+        self.printer = config.get_printer()
+        points = config.get('points').split('\n')
+        try:
+            points = [line.split(',', 1) for line in points if line.strip()]
+            self.points = [(float(p[0].strip()), float(p[1].strip()))
+                           for p in points]
+        except:
+            raise config.error("Unable to parse bed tilt points")
+        if len(self.points) < 3:
+            raise config.error("Need at least 3 points for bed_tilt_calibrate")
+        self.speed = config.getfloat('speed', 50., above=0.)
+        self.horizontal_move_z = config.getfloat('horizontal_move_z', 5.)
+        self.z_position_endstop = None
+        if config.has_section('stepper_z'):
+            zconfig = config.getsection('stepper_z')
+            self.z_position_endstop = zconfig.getfloat('position_endstop', None)
+        self.manual_probe = config.getboolean('manual_probe', None)
+        if self.manual_probe is None:
+            self.manual_probe = not config.has_section('probe')
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command(
+            'BED_TILT_CALIBRATE', self.cmd_BED_TILT_CALIBRATE,
+            desc=self.cmd_BED_TILT_CALIBRATE_help)
+    cmd_BED_TILT_CALIBRATE_help = "Bed tilt calibration script"
+    def cmd_BED_TILT_CALIBRATE(self, params):
+        self.gcode.run_script("G28")
+        probe.ProbePointsHelper(
+            self.printer, self.points, self.horizontal_move_z,
+            self.speed, self.manual_probe, self)
+    def get_position(self):
+        kin = self.printer.lookup_object('toolhead').get_kinematics()
+        return kin.get_position()
+    def finalize(self, z_offset, positions):
+        logging.info("Calculating bed_tilt with: %s", positions)
+        params = { 'x_adjust': self.bedtilt.x_adjust,
+                   'y_adjust': self.bedtilt.y_adjust,
+                   'z_adjust': z_offset }
+        logging.info("Initial bed_tilt parameters: %s", params)
+        def adjusted_height(pos, params):
+            x, y, z = pos
+            return (z - x*params['x_adjust'] - y*params['y_adjust']
+                    - params['z_adjust'])
+        def errorfunc(params):
+            total_error = 0.
+            for pos in positions:
+                total_error += adjusted_height(pos, params)**2
+            return total_error
+        new_params = mathutil.coordinate_descent(
+            params.keys(), params, errorfunc)
+        logging.info("Calculated bed_tilt parameters: %s", new_params)
+        for pos in positions:
+            logging.info("orig: %s new: %s", adjusted_height(pos, params),
+                         adjusted_height(pos, new_params))
+        z_diff = new_params['z_adjust'] - z_offset
+        if self.z_position_endstop is not None:
+            # Cartesian style robot
+            z_extra = ""
+            probe = self.printer.lookup_object('probe', None)
+            if probe is not None:
+                last_home_position = probe.last_home_position()
+                if last_home_position is not None:
+                    # Using z_virtual_endstop
+                    home_x, home_y = last_home_position[:2]
+                    z_diff -= home_x * new_params['x_adjust']
+                    z_diff -= home_y * new_params['y_adjust']
+                    z_extra = " (when Z homing at %.3f,%.3f)" % (home_x, home_y)
+            z_adjust = "stepper_z position_endstop: %.6f%s\n" % (
+                self.z_position_endstop - z_diff, z_extra)
+        else:
+            # Delta (or other) style robot
+            z_adjust = "Add %.6f to endstop position\n" % (-z_diff,)
+        msg = "%sx_adjust: %.6f y_adjust: %.6f" % (
+            z_adjust, new_params['x_adjust'], new_params['y_adjust'])
+        logging.info("bed_tilt_calibrate: %s", msg)
+        self.gcode.respond_info(
+            "%s\nTo use these parameters, update the printer config file with\n"
+            "the above and then issue a RESTART command" % (msg,))
+
+def load_config(config):
+    return BedTilt(config)

klippy/extras/delta_calibrate.py

@@ -0,0 +1,73 @@
+# Delta calibration support
+#
+# Copyright (C) 2017-2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import math, logging
+import probe, delta, mathutil
+
+class DeltaCalibrate:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        if config.getsection('printer').get('kinematics') != 'delta':
+            raise config.error("Delta calibrate is only for delta printers")
+        self.radius = config.getfloat('radius', above=0.)
+        self.speed = config.getfloat('speed', 50., above=0.)
+        self.horizontal_move_z = config.getfloat('horizontal_move_z', 5.)
+        self.manual_probe = config.getboolean('manual_probe', None)
+        if self.manual_probe is None:
+            self.manual_probe = not config.has_section('probe')
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command(
+            'DELTA_CALIBRATE', self.cmd_DELTA_CALIBRATE,
+            desc=self.cmd_DELTA_CALIBRATE_help)
+    cmd_DELTA_CALIBRATE_help = "Delta calibration script"
+    def cmd_DELTA_CALIBRATE(self, params):
+        # Setup probe points
+        points = [(0., 0.)]
+        scatter = [.95, .90, .85, .70, .75, .80]
+        for i in range(6):
+            r = math.radians(90. + 60. * i)
+            dist = self.radius * scatter[i]
+            points.append((math.cos(r) * dist, math.sin(r) * dist))
+        # Probe them
+        self.gcode.run_script("G28")
+        probe.ProbePointsHelper(self.printer, points, self.horizontal_move_z,
+                                self.speed, self.manual_probe, self)
+    def get_position(self):
+        kin = self.printer.lookup_object('toolhead').get_kinematics()
+        return kin.get_stable_position()
+    def finalize(self, z_offset, positions):
+        kin = self.printer.lookup_object('toolhead').get_kinematics()
+        logging.info("Calculating delta_calibrate with: %s", positions)
+        params = kin.get_calibrate_params()
+        logging.info("Initial delta_calibrate parameters: %s", params)
+        adj_params = ('endstop_a', 'endstop_b', 'endstop_c', 'radius',
+                      'angle_a', 'angle_b')
+        def delta_errorfunc(params):
+            total_error = 0.
+            for spos in positions:
+                x, y, z = delta.get_position_from_stable(spos, params)
+                total_error += (z - z_offset)**2
+            return total_error
+        new_params = mathutil.coordinate_descent(
+            adj_params, params, delta_errorfunc)
+        logging.info("Calculated delta_calibrate parameters: %s", new_params)
+        for spos in positions:
+            logging.info("orig: %s new: %s",
+                         delta.get_position_from_stable(spos, params),
+                         delta.get_position_from_stable(spos, new_params))
+        self.gcode.respond_info(
+            "stepper_a: position_endstop: %.6f angle: %.6f\n"
+            "stepper_b: position_endstop: %.6f angle: %.6f\n"
+            "stepper_c: position_endstop: %.6f angle: %.6f\n"
+            "radius: %.6f\n"
+            "To use these parameters, update the printer config file with\n"
+            "the above and then issue a RESTART command" % (
+                new_params['endstop_a'], new_params['angle_a'],
+                new_params['endstop_b'], new_params['angle_b'],
+                new_params['endstop_c'], new_params['angle_c'],
+                new_params['radius']))
+
+def load_config(config):
+    return DeltaCalibrate(config)

klippy/extras/display.py

@@ -0,0 +1,602 @@
+# Basic LCD display support
+#
+# Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2018  Aleph Objects, Inc <marcio@alephobjects.com>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import logging
+
+BACKGROUND_PRIORITY_CLOCK = 0x7fffffff00000000
+
+
+######################################################################
+# HD44780 (20x4 text) lcd chip
+######################################################################
+
+HD44780_DELAY = .000037
+
+class HD44780:
+    char_right_arrow = '\x7e'
+    char_thermometer = '\x00'
+    char_heater_bed = '\x01'
+    char_speed_factor = '\x02'
+    char_clock = '\x03'
+    char_degrees = '\x04'
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        # pin config
+        ppins = self.printer.lookup_object('pins')
+        pins = [ppins.lookup_pin('digital_out', config.get(name + '_pin'))
+                for name in ['rs', 'e', 'd4', 'd5', 'd6', 'd7']]
+        mcu = None
+        for pin_params in pins:
+            if mcu is not None and pin_params['chip'] != mcu:
+                raise ppins.error("hd44780 all pins must be on same mcu")
+            mcu = pin_params['chip']
+            if pin_params['invert']:
+                raise ppins.error("hd44780 can not invert pin")
+        self.pins = [pin_params['pin'] for pin_params in pins]
+        self.mcu = mcu
+        self.oid = self.mcu.create_oid()
+        self.mcu.add_config_object(self)
+        self.send_data_cmd = self.send_cmds_cmd = None
+        # framebuffers
+        self.text_framebuffer = (bytearray(' '*80), bytearray('~'*80), 0x80)
+        self.glyph_framebuffer = (bytearray(64), bytearray('~'*64), 0x40)
+        self.framebuffers = [self.text_framebuffer, self.glyph_framebuffer]
+    def build_config(self):
+        self.mcu.add_config_cmd(
+            "config_hd44780 oid=%d rs_pin=%s e_pin=%s"
+            " d4_pin=%s d5_pin=%s d6_pin=%s d7_pin=%s delay_ticks=%d" % (
+                self.oid, self.pins[0], self.pins[1],
+                self.pins[2], self.pins[3], self.pins[4], self.pins[5],
+                self.mcu.seconds_to_clock(HD44780_DELAY)))
+        cmd_queue = self.mcu.alloc_command_queue()
+        self.send_cmds_cmd = self.mcu.lookup_command(
+            "hd44780_send_cmds oid=%c cmds=%*s", cq=cmd_queue)
+        self.send_data_cmd = self.mcu.lookup_command(
+            "hd44780_send_data oid=%c data=%*s", cq=cmd_queue)
+    def send(self, cmds, is_data=False):
+        cmd_type = self.send_cmds_cmd
+        if is_data:
+            cmd_type = self.send_data_cmd
+        cmd_type.send([self.oid, cmds], reqclock=BACKGROUND_PRIORITY_CLOCK)
+        #logging.debug("hd44780 %d %s", is_data, repr(cmds))
+    def flush(self):
+        # Find all differences in the framebuffers and send them to the chip
+        for new_data, old_data, fb_id in self.framebuffers:
+            if new_data == old_data:
+                continue
+            # Find the position of all changed bytes in this framebuffer
+            diffs = [[i, 1] for i, (nd, od) in enumerate(zip(new_data, old_data))
+                     if nd != od]
+            # Batch together changes that are close to each other
+            for i in range(len(diffs)-2, -1, -1):
+                pos, count = diffs[i]
+                nextpos, nextcount = diffs[i+1]
+                if pos + 4 >= nextpos and nextcount < 16:
+                    diffs[i][1] = nextcount + (nextpos - pos)
+                    del diffs[i+1]
+            # Transmit changes
+            for pos, count in diffs:
+                chip_pos = pos
+                if fb_id == 0x80 and pos >= 40:
+                    chip_pos += 0x40 - 40
+                self.send([fb_id + chip_pos])
+                self.send(new_data[pos:pos+count], is_data=True)
+            old_data[:] = new_data
+    def init(self):
+        curtime = self.printer.get_reactor().monotonic()
+        print_time = self.mcu.estimated_print_time(curtime)
+        # Program 4bit / 2-line mode and then issue 0x02 "Home" command
+        init = [[0x33], [0x33], [0x33, 0x22, 0x28, 0x02]]
+        # Reset (set positive direction ; enable display and hide cursor)
+        init.append([0x06, 0x0c])
+        for i, cmds in enumerate(init):
+            minclock = self.mcu.print_time_to_clock(print_time + i * .100)
+            self.send_cmds_cmd.send([self.oid, cmds], minclock=minclock)
+        # Add custom fonts
+        self.glyph_framebuffer[0][:len(HD44780_chars)] = HD44780_chars
+        for i in range(len(self.glyph_framebuffer[0])):
+            self.glyph_framebuffer[1][i] = self.glyph_framebuffer[0][i] ^ 1
+        self.flush()
+    def write_text(self, x, y, data):
+        if x + len(data) > 20:
+            data = data[:20 - min(x, 20)]
+        pos = [0, 40, 20, 60][y] + x
+        self.text_framebuffer[0][pos:pos+len(data)] = data
+    def clear(self):
+        self.text_framebuffer[0][:] = ' '*80
+
+HD44780_chars = [
+    # Thermometer
+    0b00100,
+    0b01010,
+    0b01010,
+    0b01010,
+    0b01010,
+    0b10001,
+    0b10001,
+    0b01110,
+    # Heated bed
+    0b00000,
+    0b11111,
+    0b10101,
+    0b10001,
+    0b10101,
+    0b11111,
+    0b00000,
+    0b00000,
+    # Speed factor
+    0b11100,
+    0b10000,
+    0b11000,
+    0b10111,
+    0b00101,
+    0b00110,
+    0b00101,
+    0b00000,
+    # Clock
+    0b00000,
+    0b01110,
+    0b10011,
+    0b10101,
+    0b10001,
+    0b01110,
+    0b00000,
+    0b00000,
+    # Degrees
+    0b01100,
+    0b10010,
+    0b10010,
+    0b01100,
+    0b00000,
+    0b00000,
+    0b00000,
+    0b00000,
+]
+
+
+######################################################################
+# ST7920 (128x64 graphics) lcd chip
+######################################################################
+
+ST7920_DELAY = .000020 # Spec says 72us, but faster is possible in practice
+
+class ST7920:
+    char_right_arrow = '\x1a'
+    def __init__(self, config):
+        printer = config.get_printer()
+        # pin config
+        ppins = printer.lookup_object('pins')
+        pins = [ppins.lookup_pin('digital_out', config.get(name + '_pin'))
+                for name in ['cs', 'sclk', 'sid']]
+        mcu = None
+        for pin_params in pins:
+            if mcu is not None and pin_params['chip'] != mcu:
+                raise ppins.error("st7920 all pins must be on same mcu")
+            mcu = pin_params['chip']
+            if pin_params['invert']:
+                raise ppins.error("st7920 can not invert pin")
+        self.pins = [pin_params['pin'] for pin_params in pins]
+        self.mcu = mcu
+        self.oid = self.mcu.create_oid()
+        self.mcu.add_config_object(self)
+        self.send_data_cmd = self.send_cmds_cmd = None
+        self.is_extended = False
+        # framebuffers
+        self.text_framebuffer = (bytearray(' '*64), bytearray('~'*64), 0x80)
+        self.glyph_framebuffer = (bytearray(128), bytearray('~'*128), 0x40)
+        self.graphics_framebuffers = [(bytearray(32), bytearray('~'*32), i)
+                                      for i in range(32)]
+        self.framebuffers = ([self.text_framebuffer, self.glyph_framebuffer]
+                             + self.graphics_framebuffers)
+    def build_config(self):
+        self.mcu.add_config_cmd(
+            "config_st7920 oid=%u cs_pin=%s sclk_pin=%s sid_pin=%s"
+            " delay_ticks=%d" % (
+                self.oid, self.pins[0], self.pins[1], self.pins[2],
+                self.mcu.seconds_to_clock(ST7920_DELAY)))
+        cmd_queue = self.mcu.alloc_command_queue()
+        self.send_cmds_cmd = self.mcu.lookup_command(
+            "st7920_send_cmds oid=%c cmds=%*s", cq=cmd_queue)
+        self.send_data_cmd = self.mcu.lookup_command(
+            "st7920_send_data oid=%c data=%*s", cq=cmd_queue)
+    def send(self, cmds, is_data=False, is_extended=False):
+        cmd_type = self.send_cmds_cmd
+        if is_data:
+            cmd_type = self.send_data_cmd
+        elif self.is_extended != is_extended:
+            add_cmd = 0x22
+            if is_extended:
+                add_cmd = 0x26
+            cmds = [add_cmd] + cmds
+            self.is_extended = is_extended
+        cmd_type.send([self.oid, cmds], reqclock=BACKGROUND_PRIORITY_CLOCK)
+        #logging.debug("st7920 %d %s", is_data, repr(cmds))
+    def flush(self):
+        # Find all differences in the framebuffers and send them to the chip
+        for new_data, old_data, fb_id in self.framebuffers:
+            if new_data == old_data:
+                continue
+            # Find the position of all changed bytes in this framebuffer
+            diffs = [[i, 1] for i, (nd, od) in enumerate(zip(new_data, old_data))
+                     if nd != od]
+            # Batch together changes that are close to each other
+            for i in range(len(diffs)-2, -1, -1):
+                pos, count = diffs[i]
+                nextpos, nextcount = diffs[i+1]
+                if pos + 5 >= nextpos and nextcount < 16:
+                    diffs[i][1] = nextcount + (nextpos - pos)
+                    del diffs[i+1]
+            # Transmit changes
+            for pos, count in diffs:
+                count += pos & 0x01
+                count += count & 0x01
+                pos = pos & ~0x01
+                chip_pos = pos >> 1
+                if fb_id < 0x40:
+                    # Graphics framebuffer update
+                    self.send([0x80 + fb_id, 0x80 + chip_pos], is_extended=True)
+                else:
+                    self.send([fb_id + chip_pos])
+                self.send(new_data[pos:pos+count], is_data=True)
+            old_data[:] = new_data
+    def init(self):
+        cmds = [0x24, # Enter extended mode
+                0x40, # Clear vertical scroll address
+                0x02, # Enable CGRAM access
+                0x26, # Enable graphics
+                0x22, # Leave extended mode
+                0x02, # Home the display
+                0x06, # Set positive update direction
+                0x0c] # Enable display and hide cursor
+        self.send(cmds)
+        self.flush()
+    def load_glyph(self, glyph_id, data):
+        if len(data) > 32:
+            data = data[:32]
+        pos = min(glyph_id * 32, 96)
+        self.glyph_framebuffer[0][pos:pos+len(data)] = data
+    def write_text(self, x, y, data):
+        if x + len(data) > 16:
+            data = data[:16 - min(x, 16)]
+        pos = [0, 32, 16, 48][y] + x
+        self.text_framebuffer[0][pos:pos+len(data)] = data
+    def write_graphics(self, x, y, row, data):
+        if x + len(data) > 16:
+            data = data[:16 - min(x, 16)]
+        gfx_fb = y * 16 + row
+        if gfx_fb >= 32:
+            gfx_fb -= 32
+            x += 16
+        self.graphics_framebuffers[gfx_fb][0][x:x+len(data)] = data
+    def clear(self):
+        self.text_framebuffer[0][:] = ' '*64
+        zeros = bytearray(32)
+        for new_data, old_data, fb_id in self.graphics_framebuffers:
+            new_data[:] = zeros
+
+
+######################################################################
+# Icons
+######################################################################
+
+nozzle_icon = [
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000111111110000,
+    0b0001111111111000,
+    0b0001111111111000,
+    0b0001111111111000,
+    0b0000111111110000,
+    0b0000111111110000,
+    0b0001111111111000,
+    0b0001111111111000,
+    0b0001111111111000,
+    0b0000011111100000,
+    0b0000001111000000,
+    0b0000000110000000,
+    0b0000000000000000,
+    0b0000000000000000
+]
+
+bed_icon = [
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0111111111111110,
+    0b0111111111111110,
+    0b0000000000000000,
+    0b0000000000000000
+]
+
+heat1_icon = [
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0010001000100000,
+    0b0001000100010000,
+    0b0000100010001000,
+    0b0000100010001000,
+    0b0001000100010000,
+    0b0010001000100000,
+    0b0010001000100000,
+    0b0001000100010000,
+    0b0000100010001000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000
+]
+
+heat2_icon = [
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000100010001000,
+    0b0000100010001000,
+    0b0001000100010000,
+    0b0010001000100000,
+    0b0010001000100000,
+    0b0001000100010000,
+    0b0000100010001000,
+    0b0000100010001000,
+    0b0001000100010000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000,
+    0b0000000000000000
+]
+
+fan1_icon = [
+    0b0000000000000000,
+    0b0111111111111110,
+    0b0111000000001110,
+    0b0110001111000110,
+    0b0100001111000010,
+    0b0100000110000010,
+    0b0101100000011010,
+    0b0101110110111010,
+    0b0101100000011010,
+    0b0100000110000010,
+    0b0100001111000010,
+    0b0110001111000110,
+    0b0111000000001110,
+    0b0111111111111110,
+    0b0000000000000000,
+    0b0000000000000000
+]
+
+fan2_icon = [
+    0b0000000000000000,
+    0b0111111111111110,
+    0b0111000000001110,
+    0b0110010000100110,
+    0b0100111001110010,
+    0b0101111001111010,
+    0b0100110000110010,
+    0b0100000110000010,
+    0b0100110000110010,
+    0b0101111001111010,
+    0b0100111001110010,
+    0b0110010000100110,
+    0b0111000000001110,
+    0b0111111111111110,
+    0b0000000000000000,
+    0b0000000000000000
+]
+
+feedrate_icon = [
+    0b0000000000000000,
+    0b0111111000000000,
+    0b0100000000000000,
+    0b0100000000000000,
+    0b0100000000000000,
+    0b0111111011111000,
+    0b0100000010000100,
+    0b0100000010000100,
+    0b0100000010000100,
+    0b0100000011111000,
+    0b0000000010001000,
+    0b0000000010000100,
+    0b0000000010000100,
+    0b0000000010000010,
+    0b0000000000000000,
+    0b0000000000000000
+]
+
+
+######################################################################
+# LCD screen updates
+######################################################################
+
+LCD_chips = { 'st7920': ST7920, 'hd44780': HD44780 }
+
+class PrinterLCD:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.reactor = self.printer.get_reactor()
+        self.lcd_chip = config.getchoice('lcd_type', LCD_chips)(config)
+        self.lcd_type = config.get('lcd_type')
+        # printer objects
+        self.gcode = self.toolhead = self.sdcard = None
+        self.fan = self.extruder0 = self.extruder1 = self.heater_bed = None
+        # screen updating
+        self.screen_update_timer = self.reactor.register_timer(
+            self.screen_update_event)
+    # Initialization
+    FAN1_GLYPH, FAN2_GLYPH, BED1_GLYPH, BED2_GLYPH = 0, 1, 2, 3
+    def printer_state(self, state):
+        if state == 'ready':
+            self.lcd_chip.init()
+            # Load printer objects
+            self.gcode = self.printer.lookup_object('gcode')
+            self.toolhead = self.printer.lookup_object('toolhead')
+            self.sdcard = self.printer.lookup_object('virtual_sdcard', None)
+            self.fan = self.printer.lookup_object('fan', None)
+            self.extruder0 = self.printer.lookup_object('extruder0', None)
+            self.extruder1 = self.printer.lookup_object('extruder1', None)
+            self.heater_bed = self.printer.lookup_object('heater_bed', None)
+            # Load glyphs
+            self.load_glyph(self.BED1_GLYPH, heat1_icon)
+            self.load_glyph(self.BED2_GLYPH, heat2_icon)
+            self.load_glyph(self.FAN1_GLYPH, fan1_icon)
+            self.load_glyph(self.FAN2_GLYPH, fan2_icon)
+            # Start screen update timer
+            self.reactor.update_timer(self.screen_update_timer, self.reactor.NOW)
+    # ST7920 Glyphs
+    def load_glyph(self, glyph_id, data):
+        if self.lcd_type != 'st7920':
+            return
+        glyph = [0x00] * (len(data) * 2)
+        for i, bits in enumerate(data):
+            glyph[i*2] = (bits >> 8) & 0xff
+            glyph[i*2 + 1] = bits & 0xff
+        return self.lcd_chip.load_glyph(glyph_id, glyph)
+    def animate_glyphs(self, eventtime, x, y, glyph_id, do_animate):
+        frame = do_animate and int(eventtime) & 1
+        self.lcd_chip.write_text(x, y, (0, (glyph_id + frame)*2))
+    # Graphics drawing
+    def draw_icon(self, x, y, data):
+        for i, bits in enumerate(data):
+            self.lcd_chip.write_graphics(
+                x, y, i, [(bits >> 8) & 0xff, bits & 0xff])
+    def draw_progress_bar(self, x, y, width, value):
+        value = int(value * 100.)
+        data = [0x00] * width
+        char_pcnt = int(100/width)
+        for i in range(width):
+            if (i+1)*char_pcnt <= value:
+                # Draw completely filled bytes
+                data[i] |= 0xFF
+            elif (i*char_pcnt) < value:
+                # Draw partially filled bytes
+                data[i] |= (-1 << 8-((value % char_pcnt)*8/char_pcnt)) & 0xff
+        data[0] |= 0x80
+        data[-1] |= 0x01
+        self.lcd_chip.write_graphics(x, y, 0, [0xff]*width)
+        for i in range(1, 15):
+            self.lcd_chip.write_graphics(x, y, i, data)
+        self.lcd_chip.write_graphics(x, y, 15, [0xff]*width)
+    # Screen updating
+    def screen_update_event(self, eventtime):
+        self.lcd_chip.clear()
+        if self.lcd_type == 'hd44780':
+            self.screen_update_hd44780(eventtime)
+        else:
+            self.screen_update_st7920(eventtime)
+        self.lcd_chip.flush()
+        return eventtime + .500
+    def screen_update_hd44780(self, eventtime):
+        lcd_chip = self.lcd_chip
+        # Heaters
+        if self.extruder0 is not None:
+            info = self.extruder0.get_heater().get_status(eventtime)
+            lcd_chip.write_text(0, 0, lcd_chip.char_thermometer)
+            self.draw_heater(1, 0, info)
+        if self.extruder1 is not None:
+            info = self.extruder1.get_heater().get_status(eventtime)
+            lcd_chip.write_text(0, 1, lcd_chip.char_thermometer)
+            self.draw_heater(1, 1, info)
+        if self.heater_bed is not None:
+            info = self.heater_bed.get_status(eventtime)
+            lcd_chip.write_text(10, 0, lcd_chip.char_heater_bed)
+            self.draw_heater(11, 0, info)
+        # Fan speed
+        if self.fan is not None:
+            info = self.fan.get_status(eventtime)
+            lcd_chip.write_text(10, 1, "Fan")
+            self.draw_percent(14, 1, 4, info['speed'])
+        # G-Code speed factor
+        gcode_info = self.gcode.get_status(eventtime)
+        lcd_chip.write_text(0, 2, lcd_chip.char_speed_factor)
+        self.draw_percent(1, 2, 4, gcode_info['speed_factor'])
+        # SD card print progress
+        if self.sdcard is not None:
+            info = self.sdcard.get_status(eventtime)
+            lcd_chip.write_text(7, 2, "SD")
+            self.draw_percent(9, 2, 4, info['progress'])
+        # Printing time and status
+        toolhead_info = self.toolhead.get_status(eventtime)
+        lcd_chip.write_text(14, 2, lcd_chip.char_clock)
+        self.draw_time(15, 2, toolhead_info['printing_time'])
+        self.draw_status(0, 3, gcode_info, toolhead_info)
+    def screen_update_st7920(self, eventtime):
+        # Heaters
+        if self.extruder0 is not None:
+            info = self.extruder0.get_heater().get_status(eventtime)
+            self.draw_icon(0, 0, nozzle_icon)
+            self.draw_heater(2, 0, info)
+        extruder_count = 1
+        if self.extruder1 is not None:
+            info = self.extruder1.get_heater().get_status(eventtime)
+            self.draw_icon(0, 1, nozzle_icon)
+            self.draw_heater(2, 1, info)
+            extruder_count = 2
+        if self.heater_bed is not None:
+            info = self.heater_bed.get_status(eventtime)
+            self.draw_icon(0, extruder_count, bed_icon)
+            if info['target']:
+                self.animate_glyphs(eventtime, 0, extruder_count,
+                                    self.BED1_GLYPH, True)
+            self.draw_heater(2, extruder_count, info)
+        # Fan speed
+        if self.fan is not None:
+            info = self.fan.get_status(eventtime)
+            self.animate_glyphs(eventtime, 10, 0, self.FAN1_GLYPH,
+                                info['speed'] != 0.)
+            self.draw_percent(12, 0, 4, info['speed'])
+        # SD card print progress
+        if self.sdcard is not None:
+            info = self.sdcard.get_status(eventtime)
+            if extruder_count == 1:
+                x, y, width = 0, 2, 10
+            else:
+                x, y, width = 10, 1, 6
+            self.draw_percent(x, y, width, info['progress'])
+            self.draw_progress_bar(x, y, width, info['progress'])
+        # G-Code speed factor
+        gcode_info = self.gcode.get_status(eventtime)
+        if extruder_count == 1:
+            self.draw_icon(10, 1, feedrate_icon)
+            self.draw_percent(12, 1, 4, gcode_info['speed_factor'])
+        # Printing time and status
+        toolhead_info = self.toolhead.get_status(eventtime)
+        self.draw_time(10, 2, toolhead_info['printing_time'])
+        self.draw_status(0, 3, gcode_info, toolhead_info)
+    # Screen update helpers
+    def draw_heater(self, x, y, info):
+        temperature, target = info['temperature'], info['target']
+        if target and abs(temperature - target) > 2.:
+            s = "%3.0f%s%.0f" % (
+                temperature, self.lcd_chip.char_right_arrow, target)
+        else:
+            s = "%3.0f" % (temperature,)
+        if self.lcd_type == 'hd44780':
+            s += self.lcd_chip.char_degrees
+        self.lcd_chip.write_text(x, y, s)
+    def draw_percent(self, x, y, width, value):
+        self.lcd_chip.write_text(x, y, ("%d%%" % (value * 100.,)).center(width))
+    def draw_time(self, x, y, seconds):
+        seconds = int(seconds)
+        self.lcd_chip.write_text(x, y, "%02d:%02d" % (
+            seconds // (60 * 60), (seconds // 60) % 60))
+    def draw_status(self, x, y, gcode_info, toolhead_info):
+        status = toolhead_info['status']
+        if status == 'Printing' or gcode_info['busy']:
+            pos = self.toolhead.get_position()
+            status = "X%-4.0fY%-4.0fZ%-5.2f" % (pos[0], pos[1], pos[2])
+        self.lcd_chip.write_text(x, y, status)
+
+def load_config(config):
+    return PrinterLCD(config)

klippy/extras/fan.py

@@ -0,0 +1,39 @@
+# Printer cooling fan
+#
+# Copyright (C) 2016-2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import pins
+
+FAN_MIN_TIME = 0.100
+
+class PrinterFan:
+    def __init__(self, config):
+        self.last_fan_value = 0.
+        self.last_fan_time = 0.
+        self.max_power = config.getfloat('max_power', 1., above=0., maxval=1.)
+        self.kick_start_time = config.getfloat('kick_start_time', 0.1, minval=0.)
+        printer = config.get_printer()
+        self.mcu_fan = pins.setup_pin(printer, 'pwm', config.get('pin'))
+        self.mcu_fan.setup_max_duration(0.)
+        cycle_time = config.getfloat('cycle_time', 0.010, above=0.)
+        hardware_pwm = config.getboolean('hardware_pwm', False)
+        self.mcu_fan.setup_cycle_time(cycle_time, hardware_pwm)
+    def set_speed(self, print_time, value):
+        value = max(0., min(self.max_power, value))
+        if value == self.last_fan_value:
+            return
+        print_time = max(self.last_fan_time + FAN_MIN_TIME, print_time)
+        if (value and value < self.max_power
+            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(print_time, self.max_power)
+            print_time += self.kick_start_time
+        self.mcu_fan.set_pwm(print_time, value)
+        self.last_fan_time = print_time
+        self.last_fan_value = value
+    def get_status(self, eventtime):
+        return {'speed': self.last_fan_value}
+
+def load_config(config):
+    return PrinterFan(config)

klippy/extras/heater_fan.py

@@ -0,0 +1,37 @@
+# Support fans that are enabled when a heater is on
+#
+# Copyright (C) 2016-2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import fan, extruder
+
+PIN_MIN_TIME = 0.100
+
+class PrinterHeaterFan:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.heater_name = config.get("heater", "extruder0")
+        self.heater_temp = config.getfloat("heater_temp", 50.0)
+        self.fan = fan.PrinterFan(config)
+        self.mcu = self.fan.mcu_fan.get_mcu()
+        max_power = self.fan.max_power
+        self.fan_speed = config.getfloat(
+            "fan_speed", max_power, minval=0., maxval=max_power)
+        self.fan.mcu_fan.setup_start_value(0., max_power)
+    def printer_state(self, state):
+        if state == 'ready':
+            self.heater = extruder.get_printer_heater(
+                self.printer, self.heater_name)
+            reactor = self.printer.get_reactor()
+            reactor.register_timer(self.callback, reactor.NOW)
+    def callback(self, eventtime):
+        current_temp, target_temp = self.heater.get_temp(eventtime)
+        power = 0.
+        if target_temp or current_temp > self.heater_temp:
+            power = self.fan_speed
+        print_time = self.mcu.estimated_print_time(eventtime) + PIN_MIN_TIME
+        self.fan.set_speed(print_time, power)
+        return eventtime + 1.
+
+def load_config_prefix(config):
+    return PrinterHeaterFan(config)

klippy/extras/homing_override.py

@@ -0,0 +1,39 @@
+# Run user defined actions in place of a normal G28 homing command
+#
+# Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+
+class HomingOverride:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.start_pos = [config.getfloat('set_position_' + a, None)
+                          for a in 'xyz']
+        self.script = config.get('gcode')
+        self.in_script = False
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command("G28", self.cmd_G28)
+    def cmd_G28(self, params):
+        if self.in_script:
+            # Was called recursively - invoke the real G28 command
+            self.gcode.cmd_G28(params)
+            return
+        # Calculate forced position (if configured)
+        toolhead = self.printer.lookup_object('toolhead')
+        pos = toolhead.get_position()
+        homing_axes = []
+        for axis, loc in enumerate(self.start_pos):
+            if loc is not None:
+                pos[axis] = loc
+                homing_axes.append(axis)
+        toolhead.set_position(pos, homing_axes=homing_axes)
+        self.gcode.reset_last_position()
+        # Perform homing
+        try:
+            self.in_script = True
+            self.gcode.run_script(self.script)
+        finally:
+            self.in_script = False
+
+def load_config(config):
+    return HomingOverride(config)

klippy/extras/multi_pin.py

@@ -0,0 +1,54 @@
+# Virtual pin that propagates its changes to multiple output pins
+#
+# Copyright (C) 2017,2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import pins
+
+class PrinterMultiPin:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        try:
+            pins.get_printer_pins(self.printer).register_chip('multi_pin', self)
+        except pins.error:
+            pass
+        self.pin_type = None
+        self.pin_list = [pin.strip() for pin in config.get('pins').split(',')]
+        self.mcu_pins = []
+    def setup_pin(self, pin_params):
+        pin_name = pin_params['pin']
+        pin = self.printer.lookup_object('multi_pin ' + pin_name, None)
+        if pin is not self:
+            if pin is None:
+                raise pins.error("multi_pin %s not configured" % (pin_name,))
+            return pin.setup_pin(pin_params)
+        if self.pin_type is not None:
+            raise pins.error("Can't setup multi_pin %s twice" % (pin_name,))
+        self.pin_type = pin_params['type']
+        invert = ""
+        if pin_params['invert']:
+            invert = "!"
+        self.mcu_pins = [
+            pins.setup_pin(self.printer, self.pin_type, invert + pin_desc)
+            for pin_desc in self.pin_list]
+        return self
+    def get_mcu(self):
+        return self.mcu_pins[0].get_mcu()
+    def setup_max_duration(self, max_duration):
+        for mcu_pin in self.mcu_pins:
+            mcu_pin.setup_max_duration(max_duration)
+    def setup_start_value(self, start_value, shutdown_value):
+        for mcu_pin in self.mcu_pins:
+            mcu_pin.setup_start_value(start_value, shutdown_value)
+    def setup_cycle_time(self, cycle_time, hardware_pwm=False):
+        for mcu_pin in self.mcu_pins:
+            mcu_pin.setup_cycle_time(cycle_time, hardware_pwm)
+    def set_digital(self, print_time, value):
+        for mcu_pin in self.mcu_pins:
+            mcu_pin.set_digital(print_time, value)
+    def set_pwm(self, print_time, value):
+        for mcu_pin in self.mcu_pins:
+            mcu_pin.set_pwm(print_time, value)
+
+def load_config_prefix(config):
+    return PrinterMultiPin(config)

klippy/extras/output_pin.py

@@ -0,0 +1,69 @@
+# Code to configure miscellaneous chips
+#
+# Copyright (C) 2017,2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+
+PIN_MIN_TIME = 0.100
+
+class PrinterOutputPin:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        ppins = self.printer.lookup_object('pins')
+        self.is_pwm = config.getboolean('pwm', False)
+        if self.is_pwm:
+            self.mcu_pin = ppins.setup_pin('pwm', config.get('pin'))
+            cycle_time = config.getfloat('cycle_time', 0.100, above=0.)
+            hardware_pwm = config.getboolean('hardware_pwm', False)
+            self.mcu_pin.setup_cycle_time(cycle_time, hardware_pwm)
+            self.scale = config.getfloat('scale', 1., above=0.)
+        else:
+            self.mcu_pin = ppins.setup_pin('digital_out', config.get('pin'))
+            self.scale = 1.
+        self.mcu_pin.setup_max_duration(0.)
+        self.last_value_time = 0.
+        static_value = config.getfloat('static_value', None,
+                                       minval=0., maxval=self.scale)
+        if static_value is not None:
+            self.is_static = True
+            self.last_value = static_value / self.scale
+            self.mcu_pin.setup_start_value(
+                self.last_value, self.last_value, True)
+        else:
+            self.is_static = False
+            self.last_value = config.getfloat(
+                'value', 0., minval=0., maxval=self.scale) / self.scale
+            shutdown_value = config.getfloat(
+                'shutdown_value', 0., minval=0., maxval=self.scale) / self.scale
+            self.mcu_pin.setup_start_value(self.last_value, shutdown_value)
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command("SET_PIN", self.cmd_SET_PIN,
+                                    desc=self.cmd_SET_PIN_help)
+    cmd_SET_PIN_help = "Set the value of an output pin"
+    def cmd_SET_PIN(self, params):
+        pin_name = self.gcode.get_str('PIN', params)
+        pin = self.printer.lookup_object('output_pin ' + pin_name, None)
+        if pin is not self:
+            if pin is None:
+                raise self.gcode.error("Pin not configured")
+            return pin.cmd_SET_PIN(params)
+        if self.is_static:
+            raise self.gcode.error("Static pin can not be changed at run-time")
+        value = self.gcode.get_float('VALUE', params) / self.scale
+        if value == self.last_value:
+            return
+        print_time = self.printer.lookup_object('toolhead').get_last_move_time()
+        print_time = max(print_time, self.last_value_time + PIN_MIN_TIME)
+        if self.is_pwm:
+            if value < 0. or value > 1.:
+                raise self.gcode.error("Invalid pin value")
+            self.mcu_pin.set_pwm(print_time, value)
+        else:
+            if value not in [0., 1.]:
+                raise self.gcode.error("Invalid pin value")
+            self.mcu_pin.set_digital(print_time, value)
+        self.last_value = value
+        self.last_value_time = print_time
+
+def load_config_prefix(config):
+    return PrinterOutputPin(config)

klippy/extras/pid_calibrate.py

@@ -0,0 +1,127 @@
+# Calibration of heater PID settings
+#
+# Copyright (C) 2016-2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import math, logging
+import extruder, heater
+
+class PIDCalibrate:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command(
+            'PID_CALIBRATE', self.cmd_PID_CALIBRATE,
+            desc=self.cmd_PID_CALIBRATE_help)
+    cmd_PID_CALIBRATE_help = "Run PID calibration test"
+    def cmd_PID_CALIBRATE(self, params):
+        heater_name = self.gcode.get_str('HEATER', params)
+        target = self.gcode.get_float('TARGET', params)
+        write_file = self.gcode.get_int('WRITE_FILE', params, 0)
+        try:
+            heater = extruder.get_printer_heater(self.printer, heater_name)
+        except self.printer.config_error as e:
+            raise self.gcode.error(str(e))
+        print_time = self.printer.lookup_object('toolhead').get_last_move_time()
+        calibrate = ControlAutoTune(heater)
+        old_control = heater.set_control(calibrate)
+        try:
+            heater.set_temp(print_time, target)
+        except heater.error as e:
+            raise self.gcode.error(str(e))
+        self.gcode.bg_temp(heater)
+        heater.set_control(old_control)
+        if write_file:
+            calibrate.write_file('/tmp/heattest.txt')
+        Kp, Ki, Kd = calibrate.calc_final_pid()
+        logging.info("Autotune: final: Kp=%f Ki=%f Kd=%f", Kp, Ki, Kd)
+        self.gcode.respond_info(
+            "PID parameters: pid_Kp=%.3f pid_Ki=%.3f pid_Kd=%.3f\n"
+            "To use these parameters, update the printer config file with\n"
+            "the above and then issue a RESTART command" % (Kp, Ki, Kd))
+
+TUNE_PID_DELTA = 5.0
+
+class ControlAutoTune:
+    def __init__(self, heater):
+        self.heater = heater
+        # Heating control
+        self.heating = False
+        self.peak = 0.
+        self.peak_time = 0.
+        # Peak recording
+        self.peaks = []
+        # Sample recording
+        self.last_pwm = 0.
+        self.pwm_samples = []
+        self.temp_samples = []
+    # Heater control
+    def set_pwm(self, read_time, value):
+        if value != self.last_pwm:
+            self.pwm_samples.append((read_time + heater.PWM_DELAY, value))
+            self.last_pwm = value
+        self.heater.set_pwm(read_time, value)
+    def adc_callback(self, read_time, temp):
+        self.temp_samples.append((read_time, temp))
+        if self.heating and temp >= self.heater.target_temp:
+            self.heating = False
+            self.check_peaks()
+        elif (not self.heating
+              and temp <= self.heater.target_temp - TUNE_PID_DELTA):
+            self.heating = True
+            self.check_peaks()
+        if self.heating:
+            self.set_pwm(read_time, self.heater.max_power)
+            if temp < self.peak:
+                self.peak = temp
+                self.peak_time = read_time
+        else:
+            self.set_pwm(read_time, 0.)
+            if temp > self.peak:
+                self.peak = temp
+                self.peak_time = read_time
+    def check_busy(self, eventtime):
+        if self.heating or len(self.peaks) < 12:
+            return True
+        return False
+    # Analysis
+    def check_peaks(self):
+        self.peaks.append((self.peak, self.peak_time))
+        if self.heating:
+            self.peak = 9999999.
+        else:
+            self.peak = -9999999.
+        if len(self.peaks) < 4:
+            return
+        self.calc_pid(len(self.peaks)-1)
+    def calc_pid(self, pos):
+        temp_diff = self.peaks[pos][0] - self.peaks[pos-1][0]
+        time_diff = self.peaks[pos][1] - self.peaks[pos-2][1]
+        max_power = self.heater.max_power
+        Ku = 4. * (2. * max_power) / (abs(temp_diff) * math.pi)
+        Tu = time_diff
+
+        Ti = 0.5 * Tu
+        Td = 0.125 * Tu
+        Kp = 0.6 * Ku * heater.PID_PARAM_BASE
+        Ki = Kp / Ti
+        Kd = Kp * Td
+        logging.info("Autotune: raw=%f/%f Ku=%f Tu=%f  Kp=%f Ki=%f Kd=%f",
+                     temp_diff, max_power, Ku, Tu, Kp, Ki, Kd)
+        return Kp, Ki, Kd
+    def calc_final_pid(self):
+        cycle_times = [(self.peaks[pos][1] - self.peaks[pos-2][1], pos)
+                       for pos in range(4, len(self.peaks))]
+        midpoint_pos = sorted(cycle_times)[len(cycle_times)/2][1]
+        return self.calc_pid(midpoint_pos)
+    # Offline analysis helper
+    def write_file(self, filename):
+        pwm = ["pwm: %.3f %.3f" % (time, value)
+               for time, value in self.pwm_samples]
+        out = ["%.3f %.3f" % (time, temp) for time, temp in self.temp_samples]
+        f = open(filename, "wb")
+        f.write('\n'.join(pwm + out))
+        f.close()
+
+def load_config(config):
+    return PIDCalibrate(config)

klippy/extras/probe.py

@@ -0,0 +1,189 @@
+# Z-Probe support
+#
+# Copyright (C) 2017-2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import pins, homing
+
+HINT_TIMEOUT = """
+Make sure to home the printer before probing. If the probe
+did not move far enough to trigger, then consider reducing
+the Z axis minimum position so the probe can travel further
+(the Z minimum position can be negative).
+"""
+
+class PrinterProbe:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.speed = config.getfloat('speed', 5.0)
+        self.z_offset = config.getfloat('z_offset')
+        # Infer Z position to move to during a probe
+        if config.has_section('stepper_z'):
+            zconfig = config.getsection('stepper_z')
+            self.z_position = zconfig.getfloat('position_min', 0.)
+        else:
+            pconfig = config.getsection('printer')
+            self.z_position = pconfig.getfloat('minimum_z_position', 0.)
+        # Create an "endstop" object to handle the probe pin
+        ppins = self.printer.lookup_object('pins')
+        pin_params = ppins.lookup_pin('endstop', config.get('pin'))
+        mcu = pin_params['chip']
+        mcu.add_config_object(self)
+        self.mcu_probe = mcu.setup_pin(pin_params)
+        if (config.get('activate_gcode', None) is not None or
+            config.get('deactivate_gcode', None) is not None):
+            self.mcu_probe = ProbeEndstopWrapper(config, self.mcu_probe)
+        # Create z_virtual_endstop pin
+        ppins.register_chip('probe', self)
+        self.z_virtual_endstop = None
+        # Register PROBE/QUERY_PROBE commands
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command(
+            'PROBE', self.cmd_PROBE, desc=self.cmd_PROBE_help)
+        self.gcode.register_command(
+            'QUERY_PROBE', self.cmd_QUERY_PROBE, desc=self.cmd_QUERY_PROBE_help)
+    def build_config(self):
+        toolhead = self.printer.lookup_object('toolhead')
+        z_steppers = toolhead.get_kinematics().get_steppers("Z")
+        for s in z_steppers:
+            for mcu_endstop, name in s.get_endstops():
+                for mcu_stepper in mcu_endstop.get_steppers():
+                    self.mcu_probe.add_stepper(mcu_stepper)
+    def setup_pin(self, pin_params):
+        if (pin_params['pin'] != 'z_virtual_endstop'
+            or pin_params['type'] != 'endstop'):
+            raise pins.error("Probe virtual endstop only useful as endstop pin")
+        if pin_params['invert'] or pin_params['pullup']:
+            raise pins.error("Can not pullup/invert probe virtual endstop")
+        self.z_virtual_endstop = ProbeVirtualEndstop(
+            self.printer, self.mcu_probe)
+        return self.z_virtual_endstop
+    def last_home_position(self):
+        if self.z_virtual_endstop is None:
+            return None
+        return self.z_virtual_endstop.position
+    cmd_PROBE_help = "Probe Z-height at current XY position"
+    def cmd_PROBE(self, params):
+        toolhead = self.printer.lookup_object('toolhead')
+        homing_state = homing.Homing(toolhead)
+        pos = toolhead.get_position()
+        pos[2] = self.z_position
+        try:
+            homing_state.homing_move(
+                pos, [(self.mcu_probe, "probe")], self.speed, probe_pos=True)
+        except homing.EndstopError as e:
+            reason = str(e)
+            if "Timeout during endstop homing" in reason:
+                reason += HINT_TIMEOUT
+            raise self.gcode.error(reason)
+        self.gcode.reset_last_position()
+    cmd_QUERY_PROBE_help = "Return the status of the z-probe"
+    def cmd_QUERY_PROBE(self, params):
+        toolhead = self.printer.lookup_object('toolhead')
+        print_time = toolhead.get_last_move_time()
+        self.mcu_probe.query_endstop(print_time)
+        res = self.mcu_probe.query_endstop_wait()
+        self.gcode.respond_info(
+            "probe: %s" % (["open", "TRIGGERED"][not not res],))
+
+# Endstop wrapper that enables running g-code scripts on setup
+class ProbeEndstopWrapper:
+    def __init__(self, config, mcu_endstop):
+        self.mcu_endstop = mcu_endstop
+        self.gcode = config.get_printer().lookup_object('gcode')
+        self.activate_gcode = config.get('activate_gcode', "")
+        self.deactivate_gcode = config.get('deactivate_gcode', "")
+        # Wrappers
+        self.get_mcu = self.mcu_endstop.get_mcu
+        self.add_stepper = self.mcu_endstop.add_stepper
+        self.get_steppers = self.mcu_endstop.get_steppers
+        self.home_start = self.mcu_endstop.home_start
+        self.home_wait = self.mcu_endstop.home_wait
+        self.query_endstop = self.mcu_endstop.query_endstop
+        self.query_endstop_wait = self.mcu_endstop.query_endstop_wait
+        self.TimeoutError = self.mcu_endstop.TimeoutError
+    def home_prepare(self):
+        self.gcode.run_script(self.activate_gcode)
+        self.mcu_endstop.home_prepare()
+    def home_finalize(self):
+        self.gcode.run_script(self.deactivate_gcode)
+        self.mcu_endstop.home_finalize()
+
+# Wrapper that records the last XY position of a virtual endstop probe
+class ProbeVirtualEndstop:
+    def __init__(self, printer, mcu_endstop):
+        self.printer = printer
+        self.mcu_endstop = mcu_endstop
+        self.position = None
+        # Wrappers
+        self.get_mcu = self.mcu_endstop.get_mcu
+        self.add_stepper = self.mcu_endstop.add_stepper
+        self.get_steppers = self.mcu_endstop.get_steppers
+        self.home_start = self.mcu_endstop.home_start
+        self.home_wait = self.mcu_endstop.home_wait
+        self.query_endstop = self.mcu_endstop.query_endstop
+        self.query_endstop_wait = self.mcu_endstop.query_endstop_wait
+        self.home_prepare = self.mcu_endstop.home_prepare
+        self.TimeoutError = self.mcu_endstop.TimeoutError
+    def home_finalize(self):
+        self.position = self.printer.lookup_object('toolhead').get_position()
+        self.mcu_endstop.home_finalize()
+
+# Helper code that can probe a series of points and report the
+# position at each point.
+class ProbePointsHelper:
+    def __init__(self, printer, probe_points, horizontal_move_z, speed,
+                 manual_probe, callback):
+        self.printer = printer
+        self.probe_points = probe_points
+        self.horizontal_move_z = horizontal_move_z
+        self.speed = speed
+        self.manual_probe = manual_probe
+        self.callback = callback
+        self.toolhead = self.printer.lookup_object('toolhead')
+        self.results = []
+        self.busy = True
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command(
+            'NEXT', self.cmd_NEXT, desc=self.cmd_NEXT_help)
+        # Begin probing
+        self.move_next()
+        if not manual_probe:
+            while self.busy:
+                self.gcode.run_script("PROBE")
+                self.cmd_NEXT({})
+    def move_next(self):
+        x, y = self.probe_points[len(self.results)]
+        curpos = self.toolhead.get_position()
+        curpos[0] = x
+        curpos[1] = y
+        curpos[2] = self.horizontal_move_z
+        self.toolhead.move(curpos, self.speed)
+        self.gcode.reset_last_position()
+    cmd_NEXT_help = "Move to the next XY position to probe"
+    def cmd_NEXT(self, params):
+        # Record current position
+        self.toolhead.wait_moves()
+        self.results.append(self.callback.get_position())
+        # Move to next position
+        curpos = self.toolhead.get_position()
+        curpos[2] = self.horizontal_move_z
+        self.toolhead.move(curpos, self.speed)
+        if len(self.results) == len(self.probe_points):
+            self.toolhead.get_last_move_time()
+            self.finalize(True)
+            return
+        self.move_next()
+    def finalize(self, success):
+        self.busy = False
+        self.gcode.reset_last_position()
+        self.gcode.register_command('NEXT', None)
+        if success:
+            z_offset = 0.
+            if not self.manual_probe:
+                probe = self.printer.lookup_object('probe')
+                z_offset = probe.z_offset
+            self.callback.finalize(z_offset, self.results)
+
+def load_config(config):
+    return PrinterProbe(config)

klippy/extras/replicape.py

@@ -0,0 +1,229 @@
+# Code to configure miscellaneous chips
+#
+# Copyright (C) 2017,2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import logging
+import pins, mcu
+
+REPLICAPE_MAX_CURRENT = 3.84
+REPLICAPE_SHIFT_REGISTER_BUS = 1
+REPLICAPE_SHIFT_REGISTER_DEVICE = 1
+REPLICAPE_PCA9685_BUS = 2
+REPLICAPE_PCA9685_ADDRESS = 0x70
+REPLICAPE_PCA9685_CYCLE_TIME = .001
+PIN_MIN_TIME = 0.100
+
+class pca9685_pwm:
+    def __init__(self, replicape, channel, pin_params):
+        self._replicape = replicape
+        self._channel = channel
+        if pin_params['type'] not in ['digital_out', 'pwm']:
+            raise pins.error("Pin type not supported on replicape")
+        self._mcu = replicape.host_mcu
+        self._mcu.add_config_object(self)
+        self._bus = REPLICAPE_PCA9685_BUS
+        self._address = REPLICAPE_PCA9685_ADDRESS
+        self._cycle_time = REPLICAPE_PCA9685_CYCLE_TIME
+        self._max_duration = 2.
+        self._oid = None
+        self._invert = pin_params['invert']
+        self._start_value = self._shutdown_value = float(self._invert)
+        self._is_static = False
+        self._last_clock = 0
+        self._pwm_max = 0.
+        self._set_cmd = None
+    def get_mcu(self):
+        return self._mcu
+    def setup_max_duration(self, max_duration):
+        self._max_duration = max_duration
+    def setup_cycle_time(self, cycle_time, hardware_pwm=False):
+        if hardware_pwm:
+            raise pins.error("pca9685 does not support hardware_pwm parameter")
+        if cycle_time != self._cycle_time:
+            logging.info("Ignoring pca9685 cycle time of %.6f (using %.6f)",
+                         cycle_time, self._cycle_time)
+    def setup_start_value(self, start_value, shutdown_value, is_static=False):
+        if is_static and start_value != shutdown_value:
+            raise pins.error("Static pin can not have shutdown value")
+        if self._invert:
+            start_value = 1. - start_value
+            shutdown_value = 1. - shutdown_value
+        self._start_value = max(0., min(1., start_value))
+        self._shutdown_value = max(0., min(1., shutdown_value))
+        self._is_static = is_static
+        self._replicape.note_pwm_start_value(
+            self._channel, self._start_value, self._shutdown_value)
+    def build_config(self):
+        self._pwm_max = self._mcu.get_constant_float("PCA9685_MAX")
+        cycle_ticks = self._mcu.seconds_to_clock(self._cycle_time)
+        if self._is_static:
+            self._mcu.add_config_cmd(
+                "set_pca9685_out bus=%d addr=%d channel=%d"
+                " cycle_ticks=%d value=%d" % (
+                    self._bus, self._address, self._channel,
+                    cycle_ticks, self._start_value * self._pwm_max))
+            return
+        self._oid = self._mcu.create_oid()
+        self._mcu.add_config_cmd(
+            "config_pca9685 oid=%d bus=%d addr=%d channel=%d cycle_ticks=%d"
+            " value=%d default_value=%d max_duration=%d" % (
+                self._oid, self._bus, self._address, self._channel, cycle_ticks,
+                self._start_value * self._pwm_max,
+                self._shutdown_value * self._pwm_max,
+                self._mcu.seconds_to_clock(self._max_duration)))
+        cmd_queue = self._mcu.alloc_command_queue()
+        self._set_cmd = self._mcu.lookup_command(
+            "schedule_pca9685_out oid=%c clock=%u value=%hu", cq=cmd_queue)
+    def set_pwm(self, print_time, value):
+        clock = self._mcu.print_time_to_clock(print_time)
+        if self._invert:
+            value = 1. - value
+        value = int(max(0., min(1., value)) * self._pwm_max + 0.5)
+        self._replicape.note_pwm_enable(print_time, self._channel, value)
+        self._set_cmd.send([self._oid, clock, value],
+                           minclock=self._last_clock, reqclock=clock)
+        self._last_clock = clock
+    def set_digital(self, print_time, value):
+        if value:
+            self.set_pwm(print_time, 1.)
+        else:
+            self.set_pwm(print_time, 0.)
+
+class ReplicapeDACEnable:
+    def __init__(self, replicape, channel, pin_params):
+        if pin_params['type'] != 'digital_out':
+            raise pins.error("Replicape virtual enable pin must be digital_out")
+        if pin_params['invert']:
+            raise pins.error("Replicape virtual enable pin can not be inverted")
+        self.mcu = replicape.host_mcu
+        self.value = replicape.stepper_dacs[channel]
+        self.pwm = pca9685_pwm(replicape, channel, pin_params)
+    def get_mcu(self):
+        return self.mcu
+    def setup_max_duration(self, max_duration):
+        self.pwm.setup_max_duration(max_duration)
+    def set_digital(self, print_time, value):
+        if value:
+            self.pwm.set_pwm(print_time, self.value)
+        else:
+            self.pwm.set_pwm(print_time, 0.)
+
+ReplicapeStepConfig = {
+    'disable': None,
+    '1': (1<<7)|(1<<5), '2': (1<<7)|(1<<5)|(1<<6), 'spread2': (1<<5),
+    '4': (1<<7)|(1<<5)|(1<<4), '16': (1<<7)|(1<<5)|(1<<6)|(1<<4),
+    'spread4': (1<<5)|(1<<4), 'spread16': (1<<7), 'stealth4': (1<<7)|(1<<6),
+    'stealth16': 0
+}
+
+class Replicape:
+    def __init__(self, config):
+        printer = config.get_printer()
+        pins.get_printer_pins(printer).register_chip('replicape', self)
+        revisions = {'B3': 'B3'}
+        config.getchoice('revision', revisions)
+        self.host_mcu = mcu.get_printer_mcu(printer, config.get('host_mcu'))
+        # Setup enable pin
+        self.mcu_pwm_enable = pins.setup_pin(
+            printer, 'digital_out', config.get('enable_pin', '!P9_41'))
+        self.mcu_pwm_enable.setup_max_duration(0.)
+        self.mcu_pwm_start_value = self.mcu_pwm_shutdown_value = False
+        # Setup power pins
+        self.pins = {
+            "power_e": (pca9685_pwm, 5), "power_h": (pca9685_pwm, 3),
+            "power_hotbed": (pca9685_pwm, 4),
+            "power_fan0": (pca9685_pwm, 7), "power_fan1": (pca9685_pwm, 8),
+            "power_fan2": (pca9685_pwm, 9), "power_fan3": (pca9685_pwm, 10) }
+        # Setup stepper config
+        self.send_spi_cmd = None
+        self.last_stepper_time = 0.
+        self.stepper_dacs = {}
+        shift_registers = [1, 0, 0, 1, 1]
+        for port, name in enumerate('xyzeh'):
+            prefix = 'stepper_%s_' % (name,)
+            sc = config.getchoice(
+                prefix + 'microstep_mode', ReplicapeStepConfig, 'disable')
+            if sc is None:
+                continue
+            sc |= shift_registers[port]
+            if config.getboolean(prefix + 'chopper_off_time_high', False):
+                sc |= 1<<3
+            if config.getboolean(prefix + 'chopper_hysteresis_high', False):
+                sc |= 1<<2
+            if config.getboolean(prefix + 'chopper_blank_time_high', True):
+                sc |= 1<<1
+            shift_registers[port] = sc
+            channel = port + 11
+            cur = config.getfloat(
+                prefix + 'current', above=0., maxval=REPLICAPE_MAX_CURRENT)
+            self.stepper_dacs[channel] = cur / REPLICAPE_MAX_CURRENT
+            self.pins[prefix + 'enable'] = (ReplicapeDACEnable, channel)
+        self.enabled_channels = {ch: False for cl, ch in self.pins.values()}
+        if config.getboolean('servo0_enable', False):
+            shift_registers[1] |= 1
+        if config.getboolean('servo1_enable', False):
+            shift_registers[2] |= 1
+        self.sr_disabled = tuple(reversed(shift_registers))
+        if [i for i in [0, 1, 2] if 11+i in self.stepper_dacs]:
+            # Enable xyz steppers
+            shift_registers[0] &= ~1
+        if [i for i in [3, 4] if 11+i in self.stepper_dacs]:
+            # Enable eh steppers
+            shift_registers[3] &= ~1
+        if (config.getboolean('standstill_power_down', False)
+            and self.stepper_dacs):
+            shift_registers[4] &= ~1
+        self.sr_enabled = tuple(reversed(shift_registers))
+        self.host_mcu.add_config_object(self)
+        self.host_mcu.add_config_cmd("send_spi bus=%d dev=%d msg=%s" % (
+            REPLICAPE_SHIFT_REGISTER_BUS, REPLICAPE_SHIFT_REGISTER_DEVICE,
+            "".join(["%02x" % (x,) for x in self.sr_disabled])))
+    def build_config(self):
+        cmd_queue = self.host_mcu.alloc_command_queue()
+        self.send_spi_cmd = self.host_mcu.lookup_command(
+            "send_spi bus=%u dev=%u msg=%*s", cq=cmd_queue)
+    def note_pwm_start_value(self, channel, start_value, shutdown_value):
+        self.mcu_pwm_start_value |= not not start_value
+        self.mcu_pwm_shutdown_value |= not not shutdown_value
+        self.mcu_pwm_enable.setup_start_value(
+            self.mcu_pwm_start_value, self.mcu_pwm_shutdown_value)
+        self.enabled_channels[channel] = not not start_value
+    def note_pwm_enable(self, print_time, channel, value):
+        is_enable = not not value
+        if self.enabled_channels[channel] == is_enable:
+            # Nothing to do
+            return
+        self.enabled_channels[channel] = is_enable
+        # Check if need to set the pca9685 enable pin
+        on_channels = [1 for c, e in self.enabled_channels.items() if e]
+        if not on_channels:
+            self.mcu_pwm_enable.set_digital(print_time, 0)
+        elif is_enable and len(on_channels) == 1:
+            self.mcu_pwm_enable.set_digital(print_time, 1)
+        # Check if need to set the stepper enable lines
+        if channel not in self.stepper_dacs:
+            return
+        on_dacs = [1 for c in self.stepper_dacs.keys()
+                   if self.enabled_channels[c]]
+        if not on_dacs:
+            sr = self.sr_disabled
+        elif is_enable and len(on_dacs) == 1:
+            sr = self.sr_enabled
+        else:
+            return
+        print_time = max(print_time, self.last_stepper_time + PIN_MIN_TIME)
+        clock = self.host_mcu.print_time_to_clock(print_time)
+        # XXX - the send_spi message should be scheduled
+        self.send_spi_cmd.send([REPLICAPE_SHIFT_REGISTER_BUS,
+                                REPLICAPE_SHIFT_REGISTER_DEVICE, sr],
+                               minclock=clock, reqclock=clock)
+    def setup_pin(self, pin_params):
+        pin = pin_params['pin']
+        if pin not in self.pins:
+            raise pins.error("Unknown replicape pin %s" % (pin,))
+        pclass, channel = self.pins[pin]
+        return pclass(self, channel, pin_params)
+
+def load_config(config):
+    return Replicape(config)

klippy/extras/servo.py

@@ -0,0 +1,59 @@
+# Support for servos
+#
+# Copyright (C) 2017,2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import pins
+
+SERVO_SIGNAL_PERIOD = 0.020
+PIN_MIN_TIME = 0.100
+
+class PrinterServo:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.mcu_servo = pins.setup_pin(self.printer, 'pwm', config.get('pin'))
+        self.mcu_servo.setup_max_duration(0.)
+        self.mcu_servo.setup_cycle_time(SERVO_SIGNAL_PERIOD)
+        self.min_width = config.getfloat(
+            'minimum_pulse_width', .001, above=0., below=SERVO_SIGNAL_PERIOD)
+        self.max_width = config.getfloat(
+            'maximum_pulse_width', .002
+            , above=self.min_width, below=SERVO_SIGNAL_PERIOD)
+        self.max_angle = config.getfloat('maximum_servo_angle', 180.)
+        self.angle_to_width = (self.max_width - self.min_width) / self.max_angle
+        self.width_to_value = 1. / SERVO_SIGNAL_PERIOD
+        self.last_value = self.last_value_time = 0.
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command("SET_SERVO", self.cmd_SET_SERVO,
+                                    desc=self.cmd_SET_SERVO_help)
+    def set_pwm(self, print_time, value):
+        if value == self.last_value:
+            return
+        print_time = max(print_time, self.last_value_time + PIN_MIN_TIME)
+        self.mcu_servo.set_pwm(print_time, value)
+        self.last_value = value
+        self.last_value_time = print_time
+    def set_angle(self, print_time, angle):
+        angle = max(0., min(self.max_angle, angle))
+        width = self.min_width + angle * self.angle_to_width
+        self.set_pwm(print_time, width * self.width_to_value)
+    def set_pulse_width(self, print_time, width):
+        width = max(self.min_width, min(self.max_width, width))
+        self.set_pwm(print_time, width * self.width_to_value)
+    cmd_SET_SERVO_help = "Set servo angle"
+    def cmd_SET_SERVO(self, params):
+        servo_name = self.gcode.get_str('SERVO', params)
+        servo = self.printer.lookup_object('servo ' + servo_name, None)
+        if servo is not self:
+            if servo is None:
+                raise self.gcode.error("Servo not configured")
+            return servo.cmd_SET_SERVO(params)
+        print_time = self.printer.lookup_object('toolhead').get_last_move_time()
+        if 'WIDTH' in params:
+            self.set_pulse_width(print_time,
+                                 self.gcode.get_float('WIDTH', params))
+        else:
+            self.set_angle(print_time, self.gcode.get_float('ANGLE', params))
+
+def load_config_prefix(config):
+    return PrinterServo(config)