from machine import Pin,PWM
from time import sleep
def cambio (x):
    global dir 
    if dir==0:
        dir=1
    else:
        dir=0 
def fun (y):
    global i 
    i=i+1
    if i>=2:
        i=0

   

b1= Pin(12,Pin.IN,Pin.PULL_UP)
b1.irq(trigger=Pin.IRQ_FALLING,handler=cambio)
b2= Pin(13,Pin.IN,Pin.PULL_UP)
b2.irq(trigger=Pin.IRQ_FALLING,handler=fun)
pwm=PWM(Pin(19), freq=1000)
d1=Pin(22,Pin.OUT) #anti horario
d2=Pin(23,Pin.OUT)
i=0
dir=0
lista=[400,1023]
while (1):
    pwm.duty(lista[i])
        
    if dir==0:
        d1.on()
        d2.off()
    else:
        d1.off()
        d2.on()