tencent cloud

// Transmit a hexadecimal data of 0x00 to the Bluetooth device.
let buffer = new ArrayBuffer(1)
let dataView = new DataView(buffer)
dataView.setUint8(0, 0)

wx.writeBLECharacteristicValue({
  // The deviceId here must be obtained through the getBluetoothDevices or onBluetoothDeviceFound interfaces.
  deviceId,
  // The ServiceId here must be obtained from the wx.getBLEDeviceServices interface.
  serviceId,
  // The CharacteristicId Here must be obtained from the getBLEDeviceCharacteristics interface.
  characteristicId,
  // The value here is of ArrayBuffer type.
  value: buffer,
  success (res) {
    console.log('writeBLECharacteristicValue success', res.errMsg)
  }
})

wx.getBLEMTU({
  deviceId: '',
  writeType: 'write',
  success (res) {
    console.log(res)
  }
})

wx.onBLEMTUChange(function (res) {
  console.log('bluetooth mtu is', res.mtu)
})

const listener = function (res) { console.log(res) }

wx.onBLEMTUChange(listener)
wx.offBLEMTUChange(listener) // The same function object as the listener must be passed in.

wx.onBLEConnectionStateChange(function(res) {
  // This method callback can be used to handle exceptional situations such as unexpected disconnections.
  console.log(device ${res.deviceId} state has changed, connected: ${res.connected})
})

const listener = function (res) { console.log(res) }

wx.onBLEConnectionStateChange(listener)
wx.offBLEConnectionStateChange(listener) // The same function object as the listener must be passed in.

// Example of converting ArrayBuffer to hexadecimal string
function ab2hex(buffer) {
  let hexArr = Array.prototype.map.call(
    new Uint8Array(buffer),
    function(bit) {
      return ('00' + bit.toString(16)).slice(-2)
    }
  )
  return hexArr.join('');
}
wx.onBLECharacteristicValueChange(function(res) {
  console.log(characteristic ${res.characteristicId} has changed, now is ${res.value})
  console.log(ab2hex(res.value))
})

wx.offBLECharacteristicValueChange()  

// Transmit a hexadecimal data of 0x00 to the Bluetooth device.
let buffer = new ArrayBuffer(1)
let dataView = new DataView(buffer)
dataView.setUint8(0, 0)

wx.writeBLECharacteristicValue({
  // The deviceId here must be obtained through the getBluetoothDevices or onBluetoothDeviceFound interfaces.
  deviceId,
  // The ServiceId here must be obtained from the wx.getBLEDeviceServices interface.
  serviceId,
  // The CharacteristicId Here Must be Retrieved from the getBLEDeviceCharacteristics Interface
  characteristicId,
  // The Value Here is of ArrayBuffer Type
  value: buffer,
  success (res) {
    console.log('writeBLECharacteristicValue success', res.errMsg)
  }
})