import processing.serial.*;

Serial myPort; // The serial port:
int backValue = 255; // Declare variable 'backValue' and assign it the value 255

void setup() { //  The setup() function is run once, when the program starts. It's used to define initial enviroment properties.
  size(640, 360);
 
  background(backValue);
  printArray(Serial.list()); // List all the available serial ports:
  myPort = new Serial(this, "COM5", 9600); // Open the port you are using at the rate you want:
}

void draw() { //  Called directly after setup(), the draw() function continuously executes the lines of code contained inside its block until the program is stopped or noLoop() is called.
}

void mousePressed() { //The mousePressed() function is called once after every time a mouse button is pressed.
  if (backValue == 255) { //If the test evaluates to true, the statements enclosed within the block are executed
    backValue = 10;
    myPort.write(0); //low
  } else { //It specifies a block of code to execute when the expression in if is false.
    backValue = 255;
    myPort.write(1); //high
  }
  background(backValue);
}