const int analogPin = A0; 
const int ledPin = 13;    

void setup() {
  Serial.begin(115200);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  int sensorValue = analogRead(analogPin);
  float voltage = sensorValue * (5.0 / 1023.0); 

  Serial.print("MQ-2 Sensor Value: ");
  Serial.print(sensorValue);
  Serial.print(", Voltage: ");
  Serial.println(voltage);

 
  if (voltage > 2.5) {
    digitalWrite(ledPin, HIGH); 

    Serial.println("Gas detected!");
  } else {
    digitalWrite(ledPin, LOW); 
    Serial.println("No gas detected.");
  }

  delay(1000); 
}