#define MQ2_PIN 34      // MQ-2 pin A0 masuk ke GPIO 34 ESP32
#define LED_GREEN 19 // LED hijau
#define LED_RED 18     // LED merah
#define RELAY_PIN 21    // Relay (optional)

void setup() {
  Serial.begin(9600);
  pinMode(LED_GREEN, OUTPUT);
  pinMode(LED_RED, OUTPUT);
  pinMode(RELAY_PIN, OUTPUT);
}

void loop() {
  int gasValue = analogRead(MQ2_PIN);
  Serial.print("Gas Value: ");
  Serial.println(gasValue); // cek nilai gas di Serial Monitor

  // Logika yang benar:
  if (gasValue > 3000) {
    // Gas tinggi → LED merah nyala
    digitalWrite(LED_RED, HIGH);
    digitalWrite(LED_GREEN, LOW);
    digitalWrite(RELAY_PIN, HIGH);
  } else {
    // Gas rendah → LED hijau nyala
    digitalWrite(LED_RED, LOW);
    digitalWrite(LED_GREEN, HIGH);
    digitalWrite(RELAY_PIN, LOW);
  }

  delay(500);
}