const int hot = 87; //set hot parameter const int cold = 75; //set cold parameter void setup() { pinMode(A2, INPUT); //sensor pinMode(2, OUTPUT); //blue pinMode(3, OUTPUT); //green pinMode(4, OUTPUT); //red Serial.begin(9600); } void loop() { int sensor = analogRead(A2); float voltage = (sensor / 1024.0) * 5.0; float tempC = (voltage - .5) * 100; float tempF = (tempC * 1.8) + 32; Serial.print("temp: "); Serial.print(tempF); if (tempF < cold) { //cold digitalWrite(2, HIGH); digitalWrite(3, LOW); digitalWrite(4, LOW); Serial.println(" It's Cold."); } else if (tempF >= hot) { //hot digitalWrite(2, LOW); digitalWrite(3, LOW); digitalWrite(4, HIGH); Serial.println(" It's Hot."); } else { //fine digitalWrite(2, LOW); digitalWrite(3, HIGH); digitalWrite(4, LOW); Serial.println(" It's Fine."); } delay(10); }