let serial;

​

function setup() {

  serial = new p5.SerialPort();

  serial.open("COM4");  

  createCanvas(400, 400); // create a canvas

  slider = createSlider(0, 255, 0); // create a slider

  slider.position(50, 50); // set the position of the slider

}

​

function draw() {

  background(220); // clear the canvas

​

  let val = slider.value(); // get the slider value

  text("LED Brightness: " + val, 50, 50); // display the brightness value

​

  // send data to Arduino over serial

  if (frameCount % 10 == 0) { // limit the rate of sending data to avoid overloading the serial port

    serial.write(val); // send the slider value over serial

  }

}

​

​

​

​

​

​