IoT Based Simple Air Pollution Monitoring System

1int redLed = 12;
2int greenLed = 8;
3int buzzer = 10;
4int smokeA0  = A0;
5// Your threshold value
6int sensorThres = 150;
7
8void setup() {
9  pinMode(redLed, OUTPUT);
10  pinMode(greenLed, OUTPUT);
11  pinMode(buzzer,  OUTPUT);
12  pinMode(smokeA0, INPUT);
13  Serial.begin(9600);
14}
15void loop()  {
16  int analogSensor = analogRead(smokeA0);
17  Serial.print("Pin A0: ");
18  Serial.println(analogSensor);
19  // Checks if it has reached the threshold value
20  if (analogSensor > sensorThres)
21  {
22    digitalWrite(redLed, HIGH);
23    digitalWrite(greenLed, LOW);
24    tone(buzzer, 3000, 300);
25  }
26  else
27  {
28    digitalWrite(redLed, LOW);
29    digitalWrite(greenLed, HIGH);
30    noTone(buzzer);
31  }
32  delay(100);
33}