#define MQ2_ANA A1
#define BUZZER_PIN 3

void setup() {
  Serial.begin(9600);
    pinMode(MQ2_ANA, INPUT);
      pinMode(BUZZER_PIN, OUTPUT);
      }

      void loop() {
        int sensorValue = analogRead(MQ2_ANA);
          
            Serial.print("Analog: ");
              Serial.println(sensorValue);

                if(sensorValue > 500) { // Adjust this threshold value according to your sensor's sensitivity
                    for(int i = 0; i < 1000; i++) { // Buzz the buzzer for 1 second
                          digitalWrite(BUZZER_PIN, HIGH);
                                delayMicroseconds(500); // Adjust this delay to change the sound frequency
                                      digitalWrite(BUZZER_PIN, LOW);
                                            delayMicroseconds(500); // Adjust this delay to change the sound frequency
                                                }
                                                    Serial.println("Smoke detected!");
                                                      }

                                                        delay(1000);
                                                        }