let xPosition = 0; // X-axis position of the ellipse

let xMinimum = 25; // min limit of ellipse on X-axis

let xMaximum = 550; // max limit of ellipse on X-axis

​

function setup() {

  createCanvas(600, 400);

  textSize(20);

}

​

function draw() {

  background(230, 230, 250);

​

  if (!serialActive) {

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

  } else {

    text("Connected", 20, 30);

​

    // map values from photo sensor

    // onto the X-axis position of the ellipse

    xPosition = map(photoSensorValue, 0, 1023, xMinimum, xMaximum);

​

    // draw an ellipse

    ellipse(xPosition, 240, 50, 50);

​

    // print the current values

    text("xPosition = " + str(xPosition), 20, 50);

  }

}

​

function keyPressed() {

  if (key == " ") {

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

    setUpSerial();

  }

}

​

function readSerial(data) {

  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 == 1) {

      // only store values here

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

      photoSensorValue = fromArduino[0];

    }

​

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

    //SEND TO ARDUINO HERE (handshake)

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

    let sendToArduino = 1 + "\n";

    writeSerial(sendToArduino);

  }

}

​

//Arduino Code

/*

void setup() {

  Serial.begin(9600);

  pinMode(LED_BUILTIN, OUTPUT);

  // 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 isMoving = Serial.parseInt();

    if (Serial.read() == '\n') {

      int photoSensorValue = analogRead(A0);

      delay(5);

      Serial.println(photoSensorValue);

    }

  }

  digitalWrite(LED_BUILTIN, LOW);

}

*/

​