from machine import Timer, Pin, PWM

pwm = PWM(Pin(21), freq=50)
push = Pin(14, Pin.IN, Pin.PULL_UP)

def timer (x):
    global servo, direccion
    pwm.duty(int(servo))
    if direccion:
        servo = servo + 1
        if servo > 125:
            direccion = 0

    else:
        servo = servo - 1
        if servo < 25:
            direccion = 1

def mover (y):
    global direccion
    direccion = not direccion



t0 = Timer(0)
t0.init(period=10, mode=Timer.PERIODIC, callback=timer)
push.irq(trigger=Pin.IRQ_FALLING, handler=mover)

servo = 25
direccion = 1

while(1):
    pass