Example class for running a stepper motor in micopython

main.py

import machine
import time

DELAY = 0.01
STEPS = 27

class Motor:
    def __init__(self, CA1, CA2, CB1, CB2, halfSteps=False):
        self._coils = (CA1, CA2, CB1, CB2)
        self._pattern = 0
        if not halfSteps:
            self._patterns = ((0,1,0,1), (0,1,1,0), (1,0,1,0), (1,0,0,1))
        else:
            self._patterns = ((0,1,0,1), (0,1,0,0), (0,1,1,0), (0,0,1,0), 
                             (1,0,1,0), (1,0,0,0), (1,0,0,1), (0,0,0,1))
        
    def _setStep(self, w1, w2, w3, w4):
        self._coils[0].value(w1)
        self._coils[1].value(w2)
        self._coils[2].value(w3)
        self._coils[3].value(w4)
        
    def stepone(self, forward=True):
        if forward:
            self._pattern += 1
            self._pattern = self._pattern if self._pattern < len(self._patterns) else 0
        else:
            self._pattern -= 1
            self._pattern = self._pattern if self._pattern > -1 else len(self._patterns) - 1
        # move the motor    
        p = self._patterns[self._pattern]
        self._setStep(*p)
        

coils = (
    machine.Pin(26, machine.Pin.OUT),
    machine.Pin(27, machine.Pin.OUT),
    machine.Pin(14, machine.Pin.OUT),
    machine.Pin(12, machine.Pin.OUT)
    )
motor = Motor(*coils, halfSteps=False)

# then call motor.stepone() in a loop to step the motor.