let alpha = 255;

let left = 0; // True (1) if mouse is being clicked on left side of screen

let right = 0; // True (1) if mouse is being clicked on right side of screen

​

function setup() {

  createCanvas(640, 480);

  textSize(18);

}

​

function draw() {

  // one value from Arduino controls the background's red color

  background(map(rVal, 0, 1023, 0, 255), 255, 200);

​

  // the other value controls the text's transparency value

  fill(255, 0, 255, map(alpha, 0, 1023, 0, 255));

​

  if (!serialActive) {

    text("Press Space Bar to select Serial Port", 20, 30);

  } else {

    text("Connected", 20, 30);

    // Print the current values

    text('rVal = ' + str(rVal), 20, 50);

    text('alpha = ' + str(alpha), 20, 70);

  }

​

​

  // click on one side of the screen, one LED will light up

  // click on the other side, the other LED will light up

  if (mouseIsPressed) {

    if (mouseX <= width / 2) {

      left = 1;

    } else {

      right = 1;

    }

  } else {

    left = right = 0;

  }

}

​

function keyPressed() {

  if (key == " ") {

    // important to have in order to start the serial connection!!

    setUpSerial();

  }

}

​

// This function will be called by the web-serial library

// with each new *line* of data. The serial library reads

// the data until the newline and then gives it to us through

// this callback function

function readSerial(data) {

  ////////////////////////////////////

  //READ FROM ARDUINO HERE

  ////////////////////////////////////

​

  if (data != null) {

    // make sure there is actually a message

    // split the message

    let fromArduino = split(trim(data), ",");

    // if the right length, then proceed

    if (fromArduino.length == 2) {

      // only store values here

      // do everything with those values in the main draw loop

      // We take the string we get from Arduino and explicitly

      // convert it to a number by using int()

      // e.g. "103" becomes 103

      rVal = int(fromArduino[0]);

      alpha = int(fromArduino[1]);

    }

​

    //////////////////////////////////

    //SEND TO ARDUINO HERE (handshake)

    //////////////////////////////////

    let sendToArduino = left + "," + right + "\n";

    writeSerial(sendToArduino);

  }

}

​

​

​

//Arduino Code

/*

// Week 11.2 Example of bidirectional serial communication

​

// Inputs:

// - A0 - sensor connected as voltage divider (e.g. potentiometer or light sensor)

// - A1 - sensor connected as voltage divider 

//

// Outputs:

// - 2 - LED

// - 5 - LED

​

int leftLedPin = 2;

int rightLedPin = 5;

​

void setup() {

  // Start serial communication so we can send data

  // over the USB connection to our p5js sketch

  Serial.begin(9600);

​

  // We'll use the builtin LED as a status output.

  // We can't use the serial monitor since the serial connection is

  // used to communicate to p5js and only one application on the computer

  // can use a serial port at once.

  pinMode(LED_BUILTIN, OUTPUT);

​

  // Outputs on these pins

  pinMode(leftLedPin, OUTPUT);

  pinMode(rightLedPin, OUTPUT);

​

  // Blink them so we can check the wiring

  digitalWrite(leftLedPin, HIGH);

  digitalWrite(rightLedPin, HIGH);

  delay(200);

  digitalWrite(leftLedPin, LOW);

  digitalWrite(rightLedPin, LOW);

​

​

​

  // start the handshake

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

    digitalWrite(LED_BUILTIN, HIGH); // on/blink while waiting for serial data

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

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

    digitalWrite(LED_BUILTIN, LOW);

    delay(50);

  }

}

​

void loop() {

  // wait for data from p5 before doing something

  while (Serial.available()) {

    digitalWrite(LED_BUILTIN, HIGH); // led on while receiving data

​

    int left = Serial.parseInt();

    int right = Serial.parseInt();

    if (Serial.read() == '\n') {

      digitalWrite(leftLedPin, left);

      digitalWrite(rightLedPin, right);

      int sensor = analogRead(A0);

      delay(5);

      int sensor2 = analogRead(A1);

      delay(5);

      Serial.print(sensor);

      Serial.print(',');

      Serial.println(sensor2);

    }

  }

  digitalWrite(LED_BUILTIN, LOW);

}

*/

​