This basic code aims to control the LED (on the nano 33 BLE) blinking rate using P5

When you press connect, wait till the console writes 'Characteristics found' to press the change button

*/

​

//The code needs to have following functions

/*

  1 Function to connect (It should include have a callback function)

  2 function to search the characteristics and assign

  3 Function to read value (It should include a callback function)

  4 Function to control the LED

  5 Function to write a value to the characteristic (It should have a callback function) 

  6 And more.......

*/

​

//NOTE: the UUIDs should be in lower cases in when using P5

​

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 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 TO THE NANO BLE");//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("CHANGE THE BLINKING RATE");//create a button to change the blinking rate

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

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

}

​

function draw() 

{

  background(220);

}

​

//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 toggle the rate

function toggleRate(error, data)

{

  if(error)

    {

      console.log("Sorry! An error occured");

      return;

    }

   console.log("The LED is set to: ", data);

   MyBLE.write(ledChar, !data, checkErrorWritingValues);

}

//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");

    }

}

​

//function to change the blinking rate

function changeBlinkRate(error)

{

  if(!ledChar)

    {

      console.log("Something wrong happened");

      return;

    }

    MyBLE.read(ledChar, toggleRate);

​

}

​

​