//[8] Interface an ESP32 with a Co2 gas sensor with appropriate connections. Continuously print
//the Co2 concentration using the serial terminal. If the Co2 concentration is above 75%, print
//“Alarm.
#define MQ135_PIN 34   // Analog pin

void setup() {
  Serial.begin(115200);
}

void loop() {
  int sensorValue = analogRead(MQ135_PIN);   // 0–4095
  float percent = (sensorValue / 4095.0) * 100;
  Serial.print("CO2 Level: ");
  Serial.print(percent);
  Serial.println("%");
  if (percent > 75) {
    Serial.println("Alarm");
  }
  delay(2000);
}