Arudino UNO Alarm

// Arduino UNO Alarm System with PIR Sensor

int pirPin = 2;       // PIR sensor signal pin
int buzzer = 8;       // Buzzer pin
int led = 13;         // LED pin
int pirState = LOW;   // Default state: no motion

void setup() {
  pinMode(pirPin, INPUT);
  pinMode(buzzer, OUTPUT);
  pinMode(led, OUTPUT);
  Serial.begin(9600); // For monitoring in Serial Monitor
}

void loop() {
  int motion = digitalRead(pirPin); // Read PIR signal

  if (motion == HIGH) {
    // Motion detected
    digitalWrite(buzzer, HIGH);
    digitalWrite(led, HIGH);
    if (pirState == LOW) {
      Serial.println("⚠ Motion detected! Alarm ON");
      pirState = HIGH;
    }
  } else {
    // No motion
    digitalWrite(buzzer, LOW);
    digitalWrite(led, LOW);
    if (pirState == HIGH) {
      Serial.println("✔ Motion stopped! Alarm OFF");
      pirState = LOW;
    }
  }
}