p5.ble.js

APIs

All APIs:

  1. Request and Connect to Bluetooth Devices
  2. Read a Bluetooth Characteristic
  3. Write to a Bluetooth Characteristic
  4. Start and stop GATT Notifications
  5. Get disconnected from a Bluetooth Device

p5ble

// Interact with multiple devices, each new p5ble() only connect to one device
const myBLE = new p5ble();
const myOtherBLE = new p5ble();

Properties:

1. device

Once it’s connected successfully, .device will have all the information of the device

2. server

3. service

4. characteristics, array

Methods:

.connect(service, gotCharacteristics?)

Parameters:

  • Service: Service UUID(e.g. 0x1234, 0x12345678, 99999999-0000-1000-8000-00805f9b34fb) or Service Name(e.g. battery_service)
  • gotCharacteristics(optional): A callback function, e.g.
(err, characteristics) => { console.log(characteristics) }

Returns characteristics: array

.read(characteristic, dataType?, gotData?)

Parameters:

  • characteristic: The characteristic UUID that you want to read
  • dataType (optional): default to uint8, options: custom, uint16, uint32, string, int8, int16, int32, float32, float64, float32-bigEndian, float64-bigEndian.
  • gotData(optional): A callback function, e.g.
(err, data) => { console.log(data) }

Returns data

Notes about dataType parameter

  • By default, float32, float64 will read data in little-endian format. If you pass float32-bigEndian or float64-bigEndian, p5.ble.js will read data in big-endian format. Read more about Endianness.

  • If you want to handle data parsing yourself in the gotData callback, set dataType to custom

.write(characteristic, data)

Parameters:

  • characteristic: The characteristic you want to write to
  • data: String

.startNotifications(characteristic, handleNotifications, dataType?)

Parameters:

  • characteristic: The characteristic you want to start notification
  • handleNotifications: A callback function, e.g. (data) => { console.log(data) }
  • dataType (optional): default to uint8, options: custom, uint16, uint32, string, int8, int16, int32, float32, float64, float32-bigEndian, float64-bigEndian.

Notes about dataType parameter

  • By default, float32, float64 will read data in little-endian format. If you pass float32-bigEndian or float64-bigEndian, p5.ble.js will read data in big-endian format. Read more about Endianness.

  • If you want to handle data parsing yourself in the handleNotifications callback, set dataType to custom

.stopNotifications(characteristic)

Parameters:

  • characteristic: The characteristic you want to stop notification

.disconnect()

.onDisconnected(handleDisconnected)

Parameters:

  • handleDisconnected: A callback function, e.g. (device) => { console.log('Device ' + device.name + ' is disconnected.'); }

.isConnected()

returns a Boolean