Serial Communication exercise

Control ellipse using potentiometer values:

This code is controlled by potentiometer values from Arduino, and these values are set to be X coordinate, which allows the ellipse to move whenever the potentiometer is changing its direction. The only drawback was the slow response of the program and the reading of the sensors.

Code:

// variable to hold an instance of the p5.webserial library:
const serial = new p5.WebSerial();
 
// HTML button object:
let portButton;
let inData;                   // for incoming serial data
let outByte = 0;              // for outgoing data
 
function setup() {
  createCanvas(400, 300);          // make the canvas
  // check to see if serial is available:
  if (!navigator.serial) {
    alert("WebSerial is not supported in this browser. Try Chrome or MS Edge.");
  }
  // if serial is available, add connect/disconnect listeners:
  navigator.serial.addEventListener("connect", portConnect);
  navigator.serial.addEventListener("disconnect", portDisconnect);
  // check for any ports that are available:
  serial.getPorts();
  // if there's no port chosen, choose one:
  serial.on("noport", makePortButton);
  // open whatever port is available:
  serial.on("portavailable", openPort);
  // handle serial errors:
  serial.on("requesterror", portError);
  // handle any incoming serial data:
  serial.on("data", serialEvent);
  serial.on("close", makePortButton);
}
 
function draw() {
  
   background(0);
   fill(255);
   //show the values
   text("sensor value: " + inData, 30, 50);
  
   //draw ellipse using those values
   ellipse(inData, height/2, 50,70);
 
}

// if there's no port selected, 
// make a port select button appear:
function makePortButton() {
  // create and position a port chooser button:
  portButton = createButton("choose port");
  portButton.position(10, 10);
  // give the port button a mousepressed handler:
  portButton.mousePressed(choosePort);
}
 
// make the port selector window appear:
function choosePort() {
  if (portButton) portButton.show();
  serial.requestPort();
}
 
// open the selected port, and make the port 
// button invisible:
function openPort() {
  // wait for the serial.open promise to return,
  // then call the initiateSerial function
  serial.open().then(initiateSerial);
 
  // once the port opens, let the user know:
  function initiateSerial() {
    console.log("port open");
  }
  // hide the port button once a port is chosen:
  if (portButton) portButton.hide();
}
 
// pop up an alert if there's a port error:
function portError(err) {
  alert("Serial port error: " + err);
}
// read any incoming data as a string
// (assumes a newline at the end of it):
function serialEvent() {
  inData = Number(serial.read());
  console.log(inData);
}
 
// try to connect if a new serial port 
// gets added (i.e. plugged in via USB):
function portConnect() {
  console.log("port connected");
  serial.getPorts();
}
 
// if a port is disconnected:
function portDisconnect() {
  serial.close();
  console.log("port disconnected");
}
 
function closePort() {
  serial.close();
}

 

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