from machine import Pin, PWM
from time import sleep

def isrA(pin):
    global cnt, servo
    if canal_B.value()==0:
        cnt = cnt +1
        servo = servo + 1
        if servo < 25:
            servo=25

def isrB(pin):
    global cnt, servo
    if canal_A.value()==0:
        cnt = cnt -1
        servo = servo - 1
        if servo > 125:
            servo:125

canal_A = Pin(14,Pin.IN)
canal_A.irq(trigger=Pin.IRQ_FALLING, handler = isrA)
canal_B = Pin(12,Pin.IN)
canal_B.irq(trigger=Pin.IRQ_FALLING, handler = isrB)
pwm = PWM(Pin(23), freq=50)

cnt = 0
servo=75

while(1):
    print(cnt)
    pwm.duty(servo)