Added a cli script for main system calls and stepper interface script from tjmarkham/python-stepper

curtains/stepper.py

@@ -0,0 +1,77 @@
+#CURRENT APPLICATION INFO
+#200 steps/rev
+#12V, 350mA
+#Big Easy driver = 1/16 microstep mode
+#Turn a 200 step motor left one full revolution: 3200
+
+from time import sleep
+import RPi.GPIO as gpio #https://pypi.python.org/pypi/RPi.GPIO
+#import exitHandler #uncomment this and line 58 if using exitHandler
+
+class Stepper:
+	#instantiate stepper 
+	#pins = [stepPin, directionPin, enablePin]
+	def __init__(self, pins):
+		#setup pins
+		self.pins = pins
+		self.stepPin = self.pins[0]
+		self.directionPin = self.pins[1]
+		self.enablePin = self.pins[2]
+		
+		#use the broadcom layout for the gpio
+		gpio.setmode(gpio.BCM)
+		
+		#set gpio pins
+		gpio.setup(self.stepPin, gpio.OUT)
+		gpio.setup(self.directionPin, gpio.OUT)
+		gpio.setup(self.enablePin, gpio.OUT)
+		
+		#set enable to high (i.e. power is NOT going to the motor)
+		gpio.output(self.enablePin, True)
+		
+		print("Stepper initialized (step=" + self.stepPin + ", direction=" + self.directionPin + ", enable=" + self.enablePin + ")")
+	
+	#clears GPIO settings
+	def cleanGPIO(self):
+		gpio.cleanup()
+	
+	#step the motor
+	# steps = number of steps to take
+	# dir = direction stepper will move
+	# speed = defines the denominator in the waitTime equation: waitTime = 0.000001/speed. As "speed" is increased, the waitTime between steps is lowered
+	# stayOn = defines whether or not stepper should stay "on" or not. If stepper will need to receive a new step command immediately, this should be set to "True." Otherwise, it should remain at "False."
+	def step(self, steps, dir, speed=1, stayOn=False):
+		#set enable to low (i.e. power IS going to the motor)
+		gpio.output(self.enablePin, False)
+		
+		#set the output to true for left and false for right
+		turnLeft = True
+		if (dir == 'right'):
+			turnLeft = False;
+		elif (dir != 'left'):
+			print("STEPPER ERROR: no direction supplied")
+			return False
+		gpio.output(self.directionPin, turnLeft)
+
+		stepCounter = 0
+	
+		waitTime = 0.000001/speed #waitTime controls speed
+
+		while stepCounter < steps:
+			#gracefully exit if ctr-c is pressed
+			#exitHandler.exitPoint(True) #exitHandler.exitPoint(True, cleanGPIO)
+
+			#turning the gpio on and off tells the easy driver to take one step
+			gpio.output(self.stepPin, True)
+			gpio.output(self.stepPin, False)
+			stepCounter += 1
+ 
+			#wait before taking the next step thus controlling rotation speed
+			sleep(waitTime)
+		
+		if (stayOn == False):
+			#set enable to high (i.e. power is NOT going to the motor)
+			gpio.output(self.enablePin, True)
+
+		print("stepperDriver complete (turned " + dir + " " + str(steps) + " steps)")
+