Processing US

import processing.serial.*;

Serial commPort;
int X = 0;
int pX = 0;
int Y = 0;
int pY = 0;

void setup()
{
//println(Serial.list());
  commPort = new Serial(this, Serial.list()[4], 9600);
  size(800, 600);
  background(255);
}

void draw()
{
    Y = commPort.read();
    println(Y);adoad
    line(pX, pY, X, Y);
    pX = X;
    pY = Y;
    X++;
    if (X > 800) {
      X = 0;
      background(255);
    }
}