stepper.py

import RPi.GPIO as GPIO
import time
import sys

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)

enable_pin = 18
coil_A_1_pin = 4
coil_A_2_pin = 17
coil_B_1_pin = 23
coil_B_2_pin = 24

GPIO.setup(enable_pin, GPIO.OUT)
GPIO.setup(coil_A_1_pin, GPIO.OUT)
GPIO.setup(coil_A_2_pin, GPIO.OUT)
GPIO.setup(coil_B_1_pin, GPIO.OUT)
GPIO.setup(coil_B_2_pin, GPIO.OUT)

GPIO.output(enable_pin, 1)

def forward(delay, steps):
  for i in range(0, steps):
    setStep(1, 0, 1, 0)
    time.sleep(delay)
    setStep(0, 1, 1, 0)
    time.sleep(delay)
    setStep(0, 1, 0, 1)
    time.sleep(delay)
    setStep(1, 0, 0, 1)
    time.sleep(delay)
    
def backwards(delay, steps):
  for i in range(0, steps):
    setStep(1, 0, 0, 1)
    time.sleep(delay)
    setStep(0, 1, 0, 1)
    time.sleep(delay)
    setStep(0, 1, 1, 0)
    time.sleep(delay)
    setStep(1, 0, 1, 0)
    time.sleep(delay)

def setStep(w1, w2, w3, w4):
  GPIO.output(coil_A_1_pin, w1)
  GPIO.output(coil_A_2_pin, w2)
  GPIO.output(coil_B_1_pin, w3)
  GPIO.output(coil_B_2_pin, w4)

delay = sys.argv[1]
steps = sys.argv[2]
direction = sys.argv[3]

if direction == 'f':
   forward(int(delay) / 1000.0, int(steps))
elif direction == 'b':
   backwards(int(delay) / 1000.0, int(steps))