Graph A simple example of communication from the Arduino board to the computer: the value of analog input 0 is sent out the serial port. We call this "serial" communication because the connection appears to both the Arduino and the computer as a serial port, even though it may actually use a USB cable. Bytes are sent one after another (serially) from the Arduino to the computer. You can use the Arduino serial monitor to view the sent data, or it can be read by Processing, PD, Max/MSP, or any other program capable of reading data from a serial port. The Processing code below graphs the data received so you can see the value of the analog input changing over time. The circuit: Any analog input sensor is attached to analog in pin 0. created 2006 by David A. Mellis modified 14 Apr 2009 by Tom Igoe and Scott Fitzgerald This example code is in the public domain. http://www.arduino.cc/en/Tutorial/Graph void setup() { // initialize the serial communication: Serial.begin(9600); } void loop() { // send the value of analog input 0: Serial.println(analogRead(A0)); // wait a bit for the analog-to-digital converter // to stabilize after the last reading: delay(10); }