let serialInitialized = false;

​

function setup() {

  createCanvas(420, 400);

  ellipseMode(CENTER);

}

​

function draw() {

  background(0);

​

  // move the ellipse based on the potentiometer values

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

​

  fill(255);

  ellipse(xPos, height / 2, 50, 50);

}

​

function keyPressed() {

  if (key === ' ') {

    if (!serialInitialized) {

      setUpSerial();

      serialInitialized = true;

    }

  }

}

​

async function setUpSerial() {

  noLoop();

  await getPort();

  serialActive = true;

  runSerial();

  loop();

}

​

function readSerial(value) {

  potValue = int(value);

}

​