​

const ledControl1 = "B6D5146F-505A-4950-8B61-E977815F0587"; // our service

let ledControl = ledControl1.toLowerCase();

​

const led1 = "D6818D69-00EF-4A65-8804-F897676C7CCC"; //our characteristics

let led = led1.toLowerCase();

​

let mystring;

​

let ledChar; //variable to hold our characteristics

​

let MyBLE; //variable for our device

​

function setup() 

{ 

  MyBLE = new p5ble(); //creating our new BLE device

  createCanvas(400, 400);//

  const connectButton = createButton("CONNECT TRINKET");//create a button to connect to device when pressed

  connectButton.position(50, 50); //positioning

  connectButton.mousePressed(ConnectDevice);//when the button is pressed connect

  const ledButton = createButton("CHECK TRINKET");//create a button to change the blinking rate

  ledButton.position(50, 150);// positioning 

  ledButton.mousePressed(readValue);//when the button is pressed change the blinking rate

}

​

function draw() 

{

  background(220);

  if(mystring !== undefined)

    {

      text(mystring, 50, 200);

    }

}

​

//function to search for characteristics

//passing error and characteristics

function findChararacteristics(error, characteristics)

{

  if(error)//if there is an error

    {

      console.log("There might vbe and error connecting");

      return; //stop

    }

  for(let i = 0; i < characteristics.length;i++)//searching for our characteristics

    { 

      // if we find the characteristics

      if(characteristics[i].uuid == led)

      {

        //assigning the found characteristics to variable declared

        ledChar = characteristics[i];

      }

    }

  if(!ledChar)// if the characteristic isn't found

    {

      console.log("Could not find the characteristic");

    }

  else

  {

    console.log("Characteristics found");

  }

}

​

function ConnectDevice()

{ 

   MyBLE.connect(ledControl, findChararacteristics);// connect to the device

}

​

//function to retrieve value

function retrieveValue(error, value)

{

  if(error)

    {

      console.log("An error occured", error);

      return

    }

  mystring = value;

  console.log(mystring);

}

//function to read value

function readValue()

{

   if(!ledChar) 

     {

       console.log("error occured: No device");

       return;

     }

  MyBLE.read(ledChar,'string', retrieveValue);

}

//function to check if there is an error writing to the BLE

function checkErrorWritingValues(error)

{

  if(error)

    {

      console.log("Error changing the value of LED"); 

      return;

    }

  else 

    {

      console.log("Value changed successful");

    }

}

​

​