A few changes

Added correction factor
Change motor test code

640motortest.py

@@ -9,12 +9,12 @@ m4 = dw.getMotor(4)
 m5 = dw.getMotor(5)
 m6 = dw.getMotor(6)
 
-m1.setMotorSpeed(0)
-m2.setMotorSpeed(0)
-m3.setMotorSpeed(0)
-m4.setMotorSpeed(0)
-m5.setMotorSpeed(0)
-m6.setMotorSpeed(0)
+m1.off()
+m2.off()
+m3.off()
+m4.off()
+m5.off()
+m6.off()
 time.sleep(1)
 
 ##time.sleep(10)
@@ -75,10 +75,10 @@ time.sleep(1)
 print "Motor 6"
 m6.setMotorSpeed(-255)
 time.sleep(1)
-print "All stop"
-m1.setMotorSpeed(0)
-m2.setMotorSpeed(0)
-m3.setMotorSpeed(0)
-m4.setMotorSpeed(0)
-m5.setMotorSpeed(0)
-m6.setMotorSpeed(0)
+print "All off"
+m1.off()
+m2.off()
+m3.off()
+m4.off()
+m5.off()
+m6.off()

darkwater_640/PCA9685.py

@@ -96,7 +96,7 @@ class PCA9685(object):
         oldmode = self._device.readU8(MODE1);
         newmode = (oldmode & 0x7F) | 0x10    # sleep
         self._device.write8(MODE1, newmode)  # go to sleep
-        self._device.write8(PRESCALE, prescale)
+        self._device.write8(PRESCALE, int(math.floor(prescale)))
         self._device.write8(MODE1, oldmode)
         time.sleep(0.005)
         self._device.write8(MODE1, oldmode | 0x80)

darkwater_640/darkwater_640.py

@@ -227,6 +227,9 @@ class dw_Motor:
                 if (command == dw_Controller.RELEASE):
                         self.MC.setPin(self.PHpin, 0)
                         self.MC.setPin(self.ENpin, 0)
+        def off(self):
+                elf.run(dw_Controller.RELEASE, 0)
+
 
 class dw_Servo:
         def __init__(self, controller, num, freq):