const int pirPin = 2;     // PIR sensor connected to D2
const int relayPin = 3;   // Relay connected to D3
const int buzzerPin = A1;  // Buzzer connected to D4 (as per your connections)

const int buzzerFrequency = 1000;  // 1 kHz tone for the buzzer

void setup() {
  pinMode(pirPin, INPUT);       
  pinMode(relayPin, OUTPUT);    
  pinMode(buzzerPin, OUTPUT);   

  // Start serial communication
  Serial.begin(9600);
}

void loop() {
  int pirState = digitalRead(pirPin);  

  if (pirState == HIGH) {  
    digitalWrite(relayPin, HIGH);   // Turn on relay (activate connected load)
    tone(buzzerPin, buzzerFrequency);  // Start buzzing with a tone
    Serial.println("Motion detected! Relay and Buzzer ON.");
  } else {  // If no motion detected
    digitalWrite(relayPin, LOW);    // Turn off relay
    noTone(buzzerPin);  // Turn off the buzzer
    Serial.println("No motion detected.");
  }

  delay(500);  // Wait for a moment before checking again
}