# Motion detection project 

from machine import Pin, Timer, PWM
import utime

# Define GPIO pins
pir_pin = 21  # PIR sensor output pin
led_pin = 20  # LED pin
buzzer_pin = 15  # Buzzer pin
period = 5000 # Period of movement ( in ms )

# Initialize PIR sensor, LED, Timer and Buzzer
pir_sensor = Pin(pir_pin, Pin.IN)
led = Pin(led_pin, Pin.OUT)
buzzer = PWM(Pin(buzzer_pin)) #Pin(buzzer_pin, Pin.OUT)
buzzer.freq(500)
motion_timer = Timer()

# Function to detect motion and turn on the LED
def detect_motion(pin_value):
    if pir_sensor.value() == 1:
        print("Motion Detected!")
        led.on()
        buzzer.duty_u16(1000)
        motion_timer.deinit()  # Stop the timer (if running)
        motion_timer.init(mode=Timer.ONE_SHOT, period=period, callback=turn_off_led_and_buzzer)

# Function to turn off the LED and Buzzer after 5 seconds
def turn_off_led_and_buzzer(timer):
    print("Buzzer shutdown !")
    print(f"No Motion Detected for {int(period/1000)} seconds.")
    led.off()
    buzzer.duty_u16(0)

# Start the timer
motion_timer.init()
# Attach the function interupt request (irq) with PIR sensor output when pin rises or captures movement
pir_sensor.irq(trigger=Pin.IRQ_RISING, handler=detect_motion)

# Infinite loop to keep the program running
while True:
    utime.sleep_ms(10)  # Small delay for stability