How to change the name of bluetooth low energy device in Android 4.3?

Question

I am developing an application where I have to connect to Bluetooth device on Android 4.3.

And I want to change the name of CC2541 Keyfob via the Android application.

I have trying to use 0x2A00 to get the Device Name service , but it seen not working when I call the Device_Name function.

The Name_Service is null.

 private static final UUID Device_Name_UUID = UUID.fromString("00002a00-0000-1000-8000-00805f9b34fb");
private static final UUID Write_UUID = UUID.fromString("00001800-0000-1000-8000-00805f9b34fb");



    public void Device_Name(){
        BluetoothGattService Name_Service = mBluetoothGatt.getService(Write_UUID );
        if(Name_Service == null) {
            Log.d(TAG, "Name_Service service not found!");
            return;
        }

        BluetoothGattCharacteristic DeviceName = Name_Service.getCharacteristic(Device_Name_UUID);
        if(DeviceName == null) {
            Log.d(TAG, "DeviceName charateristic not found!");
            return;
        }

    }


Log.v(TAG, "readCharacteristic(DeviceName) = " + mBluetoothGatt.readCharacteristic(DeviceName));

String i = "123";       
DeviceName.setValue(i);
Log.v(TAG, "writeCharacteristic(DeviceName) = " + mBluetoothGatt.writeCharacteristic(DeviceName));

I can read the name from BLE device , but it show writeCharacteristic(DeviceName) is false when I use mBluetoothGatt.readCharacteristic(DeviceName).

Does somebody has trying to use the UUID(0x2A00) of Device Name to write the name to BLE device ??

Answer 1

You need to modify the firmware of CC2541 keyfob to add the write permission of device name by adding the code below into KeyFobApp_Init() inside keyfobdemo.c:

uint8 devNamePermission = GATT_PERMIT_READ|GATT_PERMIT_WRITE; 
GGS_SetParameter( GGS_W_PERMIT_DEVICE_NAME_ATT, sizeof ( uint8 ), &devNamePermission );

Reference: http://processors.wiki.ti.com/index.php/CC2540_DeviceNameWrite