from machine import Pin
import time

loa = Pin(19, Pin.OUT)
button = Pin(14, Pin.IN, Pin.PULL_UP)

trang_thai_loa = False
ttnutnhan_cuoi = 1

while True:
    ttnutnhan_hientai = button.value()

    if ttnutnhan_cuoi == 1 and ttnutnhan_hientai == 0:
        trang_thai_loa = not trang_thai_loa
        time.sleep(0.2)  # chống dội phím

    ttnutnhan_cuoi = ttnutnhan_hientai

    if trang_thai_loa:
        loa.value(1)
        time.sleep_us(250)
        loa.value(0)
        time.sleep_us(250)
    else:
        loa.value(0)
        time.sleep(0.01)  # nghỉ ngắn khi tắt loa