from machine import  Pin 
from time import sleep
def fun (x):
  a1.value(int(x[0]))
  b1.value(int(x[1]))
  a2.value(int(x[2]))
  b2.value(int(x[3]))
  
def camb(p):
  for i in range(3,-1,-1):
    fun(lista[i])
    sleep(0.5)

a1=Pin(23,Pin.OUT)
b1=Pin(22,Pin.OUT)
a2=Pin(21,Pin.OUT)
b2=Pin(19,Pin.OUT)
push=Pin(14,Pin.IN,Pin.PULL_UP)
push.irq(trigger=Pin.IRQ_FALLING,handler=camb)

lista=["1100","0110","0011","1001"]

while(1):
  for i in lista:
    fun(i)
    sleep(0.5)