# Arduino code ``` const int hot = 20; //set hot parameter const int cold = 10; //set cold parameter void setup() { pinMode(A2, INPUT); //sensor pinMode(2, OUTPUT); //orange 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 (cold > 0 && tempC <= cold) { //cold digitalWrite(3, HIGH); digitalWrite(2, LOW); digitalWrite(4, LOW); Serial.println(" It's Green."); } else if (tempC > cold && tempC < hot) { digitalWrite(2, HIGH); digitalWrite(3, LOW); digitalWrite(4, LOW); Serial.println(" It's Orange."); } else if (tempC >= hot) { digitalWrite(2, LOW); digitalWrite(3, LOW); digitalWrite(4, HIGH); Serial.println(" It's Red."); } delay(10); } ```