import time, board


def read_id(pin):

    L1 = board.pin(pin, board.GPIO.IN, board.GPIO.PULL_UP)
    a = []
    t1 = time.ticks_us()
    while L1.value() == 1:
        t2 = time.ticks_us()
        if time.ticks_diff(t2, t1) > 1000000:
            # raise ValueError("[MixNo]:Sensor read error")
            break
        pass

    time.sleep_us(13560)

    for i in range(1000):
        v = L1.value()
        a.append(v)
        time.sleep_us(56)

    a_c = []
    count = 0

    for i in a:
        if i == 1:
            count += 1

        elif i == 0:
            if count > 0:
                a_c.append(count)
            count = 0

    for i in range(len(a_c)):
        if a_c[i] > 10:
            a_c[i] = "1"
        else:
            a_c[i] = "0"

    B1 = "".join(a_c)
    B2 = B1[16:32]
    # print(len(B1))
    if len(B1) == 32 or len(B1) == 33 or len(B1) == 46:
        B3 = int(B2, 2)
        return B3
    else:
        return None