Created a rough outline of the stepper class.

curtains/stepper_driver.py

@@ -0,0 +1,63 @@
+from time import sleep
+import RPi.GPIO as gpio
+
+class Stepper:
+	# Initiate stepper
+	# Pins = [pin1, pin2, pin3, pin4]
+	def __init__(self, pins):
+		self.pins = pins
+		self.pin1 = self.pins[0]
+		self.pin2 = self.pins[1]
+		self.pin3 = self.pins[2]
+		self.pin4 = self.pins[3]
+
+		gpio.setmode(gpio.BCM)
+
+		for pin in self.pins:
+			gpio.setup(pin, gpio.OUT)
+			gpio.output(pin, False)
+
+	# Clears the GPIO settings
+	def cleanGPIO(self):
+		gpio.cleanup()
+
+	def step(self, rotations, dir, speed=1, forever=False):
+		StepSequence = range(0, 8)
+		StepSequence[0] = [GpioPins[0]]
+		StepSequence[1] = [GpioPins[0], GpioPins[1]]
+		StepSequence[2] = [GpioPins[1]]
+		StepSequence[3] = [GpioPins[1], GpioPins[2]]
+		StepSequence[4] = [GpioPins[2]]
+		StepSequence[5] = [GpioPins[2], GpioPins[3]]
+		StepSequence[6] = [GpioPins[3]]
+		StepSequence[7] = [GpioPins[3], GpioPins[0]]
+		
+		for pin in self.pins:
+			gpio.output(pin, True)
+
+		turnLeft = True
+		if (dir == 'right'):
+			turnLeft = False
+		elif (dir != 'left'):
+			raise ValueError('STEPPER ERROR: no direction supplied')
+			return False
+
+		steps = rotations * 500
+		waitTime = 0.000001/speed
+
+		while steps > 0:
+			for pinList in stepSequence: 
+				for pin in self.pins:
+					if pin in pinList: 
+						GPIO.output(pin, True)
+					else:
+						GPIO.output(pin, False)
+				sleep(waitTime)
+
+			steps -=1
+
+
+if __name__ == '__main__':
+	pins = [17, 18, 27, 22]
+	stepper = new Stepper(pins)
+	stepper.step(2, 'left')