Serial Port List: Open Serial Port Number
Serial Read Output: Sensor Graph:

API
The Arduino code:

int heat = 65; int light = 65; int onOff = 0;

void setup() {

  Serial.begin(9600);
  pinMode(4, INPUT); 
  Serial.println("Start");
}

void loop() {

  if (Serial.available() > 0){  //only send if you have hear back
    int input = Serial.read();

    heat  = analogRead(5);
    light  = analogRead(0);
    onOff = digitalRead(4);

    Serial.print(heat);
    Serial.print(",");
    Serial.print(light);
    Serial.print(",");
    Serial.print(onOff);
    Serial.print(",");

    Serial.print(10, BYTE);  //send a return
    Serial.flush();
   delay(20);  //you might use this instead of if available
  }
}