let portName = "COM7"; // fill in your serial port name here

let xPos=0;

let yPos=0;

let onOff=0;

let brness = 50;

let circlePos;

let counter = 0;

​

function setup() {

  createCanvas(640, 480);

  serial = new p5.SerialPort(); // make a new instance of the serialport library

  serial.on("list", printList); // set a callback function for the serialport list event

  serial.on("connected", serverConnected); // callback for connecting to the server

  serial.on("open", portOpen); // callback for the port opening

  serial.on("data", serialEvent); // callback for when new data arrives

  serial.on("error", serialError); // callback for errors

  serial.on("close", portClose); // callback for the port closing

​

  serial.list(); // list the serial ports

  serial.open(portName); // open a serial port

  circlePos = width/6;

}

​

function draw() {

  background(255);

  fill(brness*counter, brness*counter, brness*counter);

  ellipse(circlePos*(counter+1) - 50, height/2, 50, 50);

}

​

function keyPressed() {

  //Counter decides which circle to display and the brightness level of the LED

  if (keyCode === LEFT_ARROW) {

    if (counter > 0) {

      counter--;

    }

    else{

      counter = 0;

    }

  } else if (keyCode === RIGHT_ARROW) {

    if (counter < 5) {

      counter++;

    }

    else{

      counter = 5;

    }

  }

  serial.write(counter);

}

​

// get the list of ports:

function printList(portList) {

  // portList is an array of serial port names

  for (let i = 0; i < portList.length; i++) {

    // Display the list the console:

    print(i + " " + portList[i]);

  }

}

​

function serverConnected() {

  print("connected to server.");

}

​

function portOpen() {

  print("the serial port opened.");

}

​

function serialEvent() {

  // read a string from the serial port

  // until you get carriage return and newline:

  let inString = serial.readLine();

  //check to see that there's actually a string there:

  if (inString.length > 0) {

    xPos = map(inString, 0, 1023, 0, width);

  }

​

  serial.write(onOff);

}

​

function serialError(err) {

  print("Something went wrong with the serial port. " + err);

}

​

function portClose() {

  print("The serial port closed.");

}

​

/* ARDUINO CODE

​

void setup() {

  Serial.begin(9600);

  pinMode(5, OUTPUT);

  while (Serial.available() <= 0) {

    Serial.println("0,0"); // send a starting message

    delay(300);              // wait 1/3 second

  }

}

​

void loop() {

  while (Serial.available() > 0) {

    // read the incoming byte:

   int inByte = Serial.read();

   int brightness = inByte * 50;

   analogWrite(5, brightness);

  }

}

*/

​