Actually I make an update through Bluetooth. In first time I erase the memory bank and then I write an hexa File on it.
But half the time an update will don't work correctly, for every data I transfer the first writeCharacteristic will return false. It happen on an entire update half the time.
I try in debug mode but the method never return false in that case, of course it's probably a delay problem, but I can't increase the time.
This is my code for send my data :
public void sendTX(final byte[] sMessage) {
BluetoothGattService service = mBluetoothGatt.getService(UUID_SERVICE_SERIAL);
if (service != null && sMessage != null) {
Log.d(TAG,"sMessage : " + sMessage);
final BluetoothGattCharacteristic characteristic = service.getCharacteristic(UUID_TX);
if (characteristic != null) {
Thread thread = new Thread() {
public void run() {
if (sMessage.length > 20) {
for (int i = 0; i < sMessage.length; i += 20) {
byte[] byteArraySplit = Arrays.copyOfRange(sMessage, i, i + 20 < sMessage.length ? i + 20 : sMessage.length);
characteristic.setWriteType(BluetoothGattCharacteristic.WRITE_TYPE_NO_RESPONSE);
characteristic.setValue(byteArraySplit);
while(!mBluetoothGatt.writeCharacteristic(characteristic)) {
try {
TimeUnit.MILLISECONDS.sleep(15);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
} else {
characteristic.setWriteType(BluetoothGattCharacteristic.WRITE_TYPE_NO_RESPONSE);
characteristic.setValue(sMessage);
while(!mBluetoothGatt.writeCharacteristic(characteristic)){
try {
TimeUnit.MILLISECONDS.sleep(15);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
};
thread.start();
} else {
Log.d(TAG, "UUID TX null");
}
} else {
Log.d(TAG, "Service BLE null");
}
}
And this is the code of the native writeCharacteristic method :
public boolean writeCharacteristic(BluetoothGattCharacteristic characteristic) {
if ((characteristic.getProperties() & BluetoothGattCharacteristic.PROPERTY_WRITE) == 0
&& (characteristic.getProperties() &
BluetoothGattCharacteristic.PROPERTY_WRITE_NO_RESPONSE) == 0) return false;
if (VDBG) Log.d(TAG, "writeCharacteristic() - uuid: " + characteristic.getUuid());
if (mService == null || mClientIf == 0 || characteristic.getValue() == null) return false;
BluetoothGattService service = characteristic.getService();
if (service == null) return false;
BluetoothDevice device = service.getDevice();
if (device == null) return false;
synchronized(mDeviceBusy) {
if (mDeviceBusy) return false;
mDeviceBusy = true;
}
try {
mService.writeCharacteristic(mClientIf, device.getAddress(),
characteristic.getInstanceId(), characteristic.getWriteType(),
AUTHENTICATION_NONE, characteristic.getValue());
} catch (RemoteException e) {
Log.e(TAG,"",e);
mDeviceBusy = false;
return false;
}
return true;
}
