--->>> 예제 :  stepper_motor.py  <<<----------------------
import RPi.GPIO as GPIO
import time
from collections import deque
GPIO.setmode(GPIO.BOARD)
AIN1=15
BIN1=16
AIN2=18
BIN2=22
sig=deque([1,0,0,0])
step=400
dir=1
GPIO.setup(AIN1,GPIO.OUT,initial=GPIO.LOW)
GPIO.setup(BIN1,GPIO.OUT,initial=GPIO.LOW)
GPIO.setup(AIN2,GPIO.OUT,initial=GPIO.LOW)
GPIO.setup(BIN2,GPIO.OUT,initial=GPIO.LOW)
try:
    while 1:
        for cnt in range(0,step):
            GPIO.output(AIN1,sig[0])
            GPIO.output(BIN1,sig[1])
            GPIO.output(AIN2,sig[2])
            GPIO.output(BIN2,sig[3])
            time.sleep(0.01)
            sig.rotate(dir)
        dir=dir*-1
except KeyboardInterrupt:
    pass
GPIO.cleanup()
​