const int pirPin = 2;   // PIR sensor pin
const int ledPin = 13;  // LED pin
const int buzzerPin = 8; // Piezo buzzer pin

void setup() {
  pinMode(pirPin, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int motion = digitalRead(pirPin); // Read PIR sensor
  if (motion == HIGH) {             // If motion is detected
    digitalWrite(ledPin, HIGH);     // Turn on the LED
    tone(buzzerPin, 1000, 500); // Play a 1000Hz tone for 0.5 seconds
    Serial.println("Motion detected!"); // Print message to serial monitor
  } else {                          // If no motion is detected
    digitalWrite(ledPin, LOW);      // Turn off the LED
  }
  delay(100);  // Delay for stability
}