from machine import Pin, ADC
import time

# --- Pins ---
pir = Pin(14, Pin.IN)
led = Pin(2, Pin.OUT)
mq2 = ADC(Pin(36))
mq2.atten(ADC.ATTN_11DB)

# --- Thresholds ---
GAS_THRESHOLD = 300  # adjust according to MQ-2 calibration

# --- Main Loop ---
while True:
    gas_value = mq2.read()
    motion = pir.value()

    print(f"Gas: {gas_value}, Motion: {motion}")

    # Emergency Alert Condition
    if gas_value > GAS_THRESHOLD and motion == 1:
        # Flash LED rapidly
        for _ in range(10):  # flash 10 times
            led.on()
            time.sleep(0.1)
            led.off()
            time.sleep(0.1)
    else:
        led.off()

    time.sleep(0.5)