#define POT_PIN A0
#define FAN_PIN 9

void setup() {
  Serial.begin(9600);
  pinMode(FAN_PIN, OUTPUT);
}

void loop() {
  int analogValue = analogRead(POT_PIN);
  float temperature = (analogValue * 100.0) / 1023.0;

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");

  int fanSpeed;

  if (temperature < 25.0) {
    fanSpeed = 0;
    Serial.println("Fan is OFF");
  } 
  else if (temperature < 30.0) {
    fanSpeed = 85; // Low speed (~33%)
    Serial.println("Fan is ON at LOW speed");
  } 
  else if (temperature < 35.0) {
    fanSpeed = 170; // Medium speed (~66%)
    Serial.println("Fan is ON at MEDIUM speed");
  } 
  else {
    fanSpeed = 255; // High speed (full)
    Serial.println("Fan is ON at HIGH speed");
  }

  analogWrite(FAN_PIN, fanSpeed);
  delay(1000);
}