added basic functions for stepping, changing direction and enabling

disabling the driver

stepper.py

@@ -0,0 +1,67 @@
+import RPi.GPIO as GPIO
+from time import sleep
+import logging
+from logging import debug
+logging.basicConfig(level=logging.DEBUG)
+
+
+GPIO.setmode(GPIO.BCM)
+
+PINS = {
+    'direction': [17, 0], # 1 = ckw, 0 = ccw
+    'step':      [27, 0],
+    'state':     [22, 1]  # 1 = disabled, 0 = enabled
+}
+# speed limit 0.0005 s = 500us (could be 1us) waiting between high and low
+# je hoeher die motor spannugn, desto lauter
+
+# initialize
+for name, pin in PINS.items():
+    GPIO.setup(pin[0], GPIO.OUT, initial=pin[1])
+
+def disable():
+    debug('Disabled')
+    GPIO.output(PINS['state'][0], 1)
+
+
+def enable():
+    debug('Enabled')
+    GPIO.output(PINS['state'][0], 0)
+
+
+def change_direction():
+    debug('changing direction')
+    GPIO.output(PINS['direction'][0], not GPIO.input(PINS['direction'][0]))
+
+
+def change_state():
+    debug('changing state')
+    GPIO.output(PINS['state'][0], not GPIO.input(PINS['state'][0]))
+
+
+def step(steps=1, direction=None):
+    if direction:
+        GPIO.output(PINS['direction'][0], direction)
+    for step in range(steps):
+        GPIO.output(PINS['step'][0], 1)
+        sleep(0.005)
+        GPIO.output(PINS['step'][0], 0)
+        sleep(0.005)
+
+if __name__ == '__main__':
+    try:
+        while True:
+#             disable()
+#             debug('stepping ccw')
+#             step(200, 0)
+# 
+#             enable()
+#             debug('stepping cw')
+#             step(200, 1)
+            step(100)
+            change_direction()
+            change_state()
+    except KeyboardInterrupt:
+        debug('cleaning up')
+        disable()
+        GPIO.cleanup()