from machine import Pin, PWM
import time

in1=Pin(18,Pin.OUT)
in2=Pin(5,Pin.OUT)
in3=Pin(16,Pin.OUT)
in4=Pin(4,Pin.OUT)
enA=PWM(Pin(21))
enB=PWM(Pin(2))
enA.freq(1000)
enB.freq(1000)


while True:
    # motor 1 forward direction
    in1.on()
    in4.on()
    enA.duty(1023)
    time.sleep(1)

    # motor 1 reverse direction
    in1.off()
    in4.off() 
    enA.duty(1)  
    time.sleep(1)

    # motor 2 forward direction
    in2.on()
    in3.on()
    enB.duty(1023)
    time.sleep(1)

    # motor 2 reverse direction
    in2.off()
    in3.off()
    enB.duty(1)
    time.sleep(1)