int dout = 7;
int buzer = 5;
int led1 = 4;

void setup() {
  pinMode(dout, INPUT);
  pinMode(buzer, OUTPUT);
  pinMode(led1, OUTPUT);
  Serial.begin(9600);
  
   digitalWrite(buzer, LOW);
  digitalWrite(led1, LOW);
  
  Serial.println("Gas Sensor System Started");
  Serial.println("Monitoring gas levels...");
}

void loop() {
  // Read gas sensor value
  int gasValue = digitalRead(dout);
  

  Serial.print("Gas Sensor Value: ");
  Serial.println(gasValue);
  
  // Check if gas is detected
  if (gasValue == HIGH) {
    
    digitalWrite(led1, HIGH);    
    
    
    tone(buzer, 1000);  // 1000Hz frequency
    
    Serial.println("ALERT! Gas detected!");
    Serial.println("LED ON - BUZZER SOUNDING");
    
  } else {
    
    digitalWrite(led1, LOW);       
    noTone(buzer);               
    
    Serial.println("Normal - No gas detected");
  }
  
  delay(1000); 
}