stepper/stepper.py

import RPi.GPIO as gpio
from time import sleep
# import logging
# from logging import debug
# logging.basicConfig(level=logging.DEBUG)


# speed limit 0.0005 s = 500us (could be 1us) waiting between high and low
# je hoeher die motor spannugn, desto lauter

class Stepper():

    def __init__(self, pins):
        # pins = [state step direction]
        self.pins = pins

        gpio.setmode(gpio.BCM)

        for pin in self.pins:
            gpio.setup(pin, gpio.OUT)

    def disable(self):
        ''' Disable the stepper motor driver '''
#         debug('Disabled')
        gpio.output(self.pins[0], 1)


    def enable(self):
        ''' Enable the stepper motor driver '''
#         debug('Enabled')
        gpio.output(self.pins[0], 0)


    def change_state(self):
        ''' Toggle between enabled and disabled state '''
#         debug('changing state')
        gpio.output(self.pins[0], not gpio.input(self.pins[0]))


    def change_direction(self, direction=None):
        ''' Change the direction '''
#         debug('changing direction')
        gpio.output(self.pins[2], not gpio.input(self.pins[2]))


    def get_direction(self, direction):
        ''' Translate everything but left and ccw to right '''
        return 0 if direction in ['left', 'ccw'] else 1


    def set_direction(self, direction):
        ''' Set the gpio direction output pin to the desired direction '''
        gpio.output(self.pins[2], self.get_direction(direction))


    def single_step(self):
        ''' Do a single step pulse '''
        gpio.output(self.pins[1], 1)
        sleep(0.000001) # min interval in which high gets recognized
        gpio.output(self.pins[1], 0)


    def step(self, steps=1, direction=None):
        ''' Do *steps* into *direction* '''
        self.set_direction(direction)
        for step in range(steps):
            self.single_step()
            sleep(0.002)


    def rotate(self, degrees=1.8, direction=None):
        ''' Rotate *degrees* into *direction* '''
        self.set_direction(direction)
        for step in range(int(degrees/1.8)):
            self.single_step()
            sleep(0.002)


    def release(self):
        self.disable()
        gpio.cleanup()


if __name__ == '__main__':

    try:
        s = Stepper([22, 27, 17])
        s.enable()
        s.step(100, 'left')
        sleep(1)
        s.step(100)
        sleep(1)
        s.rotate(360)
        sleep(1)
        s.rotate(360, 'ccw')
        sleep(1)
        s.rotate(1)
#         s.step(10)
#         sleep(1)
#         s.step()
#         sleep(1)
#         s.step(direction='left')

    except KeyboardInterrupt:
#         debug('cleaning up')
        s.release()