Processing Serial Write

import processing.serial.*;
Serial myPort;
char HEADER = 'H';
short LF = 10;

int slider1X;
int slider2X;
int slider1Y;
int slider2Y;
int slider1Value;
int slider2Value;
int prevslider1Value;
int prevslider2Value;
int sliderGrip;
int baseX;
int sliderThick;

void setup(){
  size(640,480);
  myPort = new Serial(this,Serial.list()[2],9600);
  baseX = width/4;
  slider1Y = height * 1/6;
  slider2Y = height * 1/2;
  slider1X = baseX;
  slider2X = baseX + 10;
  slider1Value = 0;
  slider2Value = 0;
  prevslider1Value = 0;
  prevslider2Value = 0;
  sliderGrip = 20;
  sliderThick = height * 1/6;
}

void draw(){
  background(255,122,122);
  fill(0);
  rect(0,0,baseX,height);
  fill(slider1Value);
  rect(baseX,slider1Y,slider1Value + sliderGrip,sliderThick);
  fill(slider2Value);
  rect(baseX,slider2Y,slider2Value + sliderGrip,sliderThick);
  fill(122,122,122);

  fill(122);
  rect(baseX + slider1Value,slider1Y,sliderGrip,sliderThick);
  rect(baseX + slider2Value,slider2Y,sliderGrip,sliderThick);
  if(mouseY > slider1Y && mouseY < slider1Y + sliderThick && mousePressed){
   slider1Value = mouseX - baseX - sliderGrip/2;
  }
  slider1Value = constrain(slider1Value,0,255);
  if(mouseY > slider2Y && mouseY < slider2Y + sliderThick && mousePressed){
   slider2Value = mouseX - baseX - sliderGrip/2;
  }
  slider2Value = constrain(slider2Value,0,255);
  textSize(32);
  fill(255);
  text("Yellow", 20, slider1Y + sliderThick * 2/3);
  text("  Red", 20, slider2Y + sliderThick * 2/3);

  text(slider1Value,500,50);
  text(slider2Value,500,100);

  if(slider1Value != prevslider1Value || slider2Value != prevslider2Value){
    myPort.write(slider1Value);
    myPort.write(",");
    myPort.write(slider2Value);
  }

  prevslider1Value = slider1Value;
  prevslider2Value = slider2Value;
}