from machine import Pin
import time

relay = Pin(19, Pin.OUT)
button = Pin(8, Pin.IN, Pin.PULL_UP)

state = False
last_button = 1

# tắt relay ban đầu (active LOW)
relay.value(1)

while True:
    current_button = button.value()

    # phát hiện nhấn (1 → 0)
    if last_button == 1 and current_button == 0:
        state = not state

        # relay active LOW
        relay.value(0 if state else 1)

    last_button = current_button
    time.sleep(0.05)