Android BLE特征setValue无法写入正确的数据
问题描述:
我正在尝试开发一个Android应用程序,该应用程序使用BLE连接到基于NRF51822的系统。目的是为我的自定义特性写一个3字节的值(RGB)。Android BLE特征setValue无法写入正确的数据
Android是GATT客户端,基于NRF51的设备是GATT服务器。
我能够建立ble连接并成功发现我的特征。
但是数据发送部分(setValue)给我带来麻烦。不管我写什么3个字节,我上NRF51侧
下同常量数据是我rellevant码(安卓)
@Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
Log.d("BLENotifier", "BLE GAT : SERVICES DISCOVERED");
for(BluetoothGattService gs: gatt.getServices()) {
Log.d("BLENotifier", "SERVICE = " + gs.getUuid().toString());
}
//SELECT MY CHARACTERSTIC
ble_my_characterstic = gatt.getService(ble_service_uuid).getCharacteristic(ble_characterstic_uuid);
Log.d("BLENotifier", "BLE SELECTED CHARACTERSTIC " + ble_my_characterstic.getUuid().toString());
ble_connected = true;
}
public void writedata(String data){
//WRITE DATA TO MY CHARACTERSTIC
if(ble_my_characterstic != null && ble_connected == true){
my_gatt_handle.executeReliableWrite();
//ble_my_characterstic.setWriteType(BluetoothGattCharacteristic.WRITE_TYPE_NO_RESPONSE);
ble_my_characterstic.setValue(hexStringToByteArray(data));
my_gatt_handle.writeCharacteristic(ble_my_characterstic);
Log.d("BLENotifier", "BLE WRITE DATA " + data);
}
public static byte[] hexStringToByteArray(String s) {
int len = s.length();
byte[] data = new byte[len/2];
for (int i = 0; i < len; i += 2) {
data[i/2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+ Character.digit(s.charAt(i+1), 16));
}
Log.d("BLENotifier", "hexStringToByteArray " + Integer.toString((int)data[0]) + " " + Integer.toString((int)data[1]) + " " + Integer.toString((int)data[2]));
return data;
}
我调用writeData
方法ble_handle.writedata("0000FF")
这就是我得到的NRF51侧
R = 4 | G = 239 | B= 1
感谢
答
我的确如此。没有确切答案,但可能会对您有所帮助。
@Override
public void onServicesDiscovered(BluetoothGatt gatt, int status)
{
List<BluetoothGattService> services = gatt.getServices();
Log.i("onServicesDiscovered", services.toString());
keepConnect=services.get(3).getCharacteristics().get(0);
if(keepConnect!=null){
writeCharacteristic(gatt,keepConnect);
}
}
private void writeCharacteristic(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic)
{
byte[] byteData = hexToBytes("6fd362e40ebcd0945bf58dc4");
byte[] writeData = new byte[byteData.length];
for (int i = 0; i < byteData.length; i++) {
writeData[i] = byteData[i];
}
characteristic.setValue(writeData);
gatt.writeCharacteristic(characteristic);
}
public static byte[] hexToBytes(String hexRepresentation) {
int len = hexRepresentation.length();
byte[] data = new byte[len/2];
for (int i = 0; i < len; i += 2) {
data[i/2] = (byte) ((Character.digit(hexRepresentation.charAt(i), 16) << 4)
+ Character.digit(hexRepresentation.charAt(i + 1), 16));
}
return data;
}
任何特别的原因用于复制的字节1:1从byteData []到写数据[]? – Ankit