import processing.serial.*; 
 
Serial port;        // The serial port 
int thisByte = -1;  // Variable to hold keystoke values 
int whichKey = -1;  // Incoming serial data 
PFont fontA;        // Font for printing 
 
void setup() { 
 
  size(200, 200); 
 
  // Load and prep fonts to print to window 
  fontA = loadFont("CourierNewPSMT-24.vlw"); 
  textFont(fontA, 24); 
 
  // List all the available serial ports: 
  println(Serial.list()); 
 
  // I know that the first port in the serial list on my mac 
  // is always my  Keyspan adaptor, so I open Serial.list()[0]. 
  // In Windows, this usually opens COM1. 
  // Open whatever port is the one you're using. 
  port = new Serial(this, Serial.list()[0], 9600); 
 
  // send a capital A out the serial port: 
  port.write(65); 
} 
 
void draw() { 
  background(0); 
  text("Received: " + thisByte, 10, 130); 
  text("Sent: " + whichKey, 10, 100); 
  // If there are bytes available in the input buffer, 
  // Read them and print them: 
  while (port.available() > 0) { 
    thisByte = port.read(); 
  } 
} 
 
void keyPressed() { 
  // Send the keystroke out: 
  port.write(key); 
  //000port.write(0); 
  whichKey = key; 
} 
 
 
/* 
 
I often test with PIC microcontrollers 
using Microengineering Labs' PicBasic Pro. 
 
Here's a test program that takes whatever you typed 
and sends back the next value higher. 
 
inByte var byte 
 
main: 
  serin2 portc.7, 16468, [inByte] 
  serout2 portc.6, 16468, [inbyte+1] 
goto main 
 
*/