Windows 10 UWP Bluetooth Connection with Arduino

Question

I was trying to find ways to find and connect Arduino via Bluetooth through UWP app, so with lots of fiddling I found two ways(couldn't find any official MS documentation on that, unfortunately) So one method is

            DeviceInformationCollection availableDevices = await BluetoothSerial.listAvailableDevicesAsync();
        foreach (DeviceInformation device in availableDevices)
        {
            deviceList.Add(device);

        }

This returns a Bluetooth device named "Dev B",and it is actually my arduino's Bluetooth module. Even though there are other devices available paired/unpaired this method always returns just "Dev B".

And then I use this function to connect with Arduino

            var selectedDevice = (DeviceInformation)DeviceListView.SelectedItem;
        uint BaudRate = 9600;
        var connection = new BluetoothSerial(selectedDevice.Name);
        arduino = new RemoteDevice(connection);
        connection.begin(BaudRate, SerialConfig.SERIAL_8N1);
        connection.ConnectionEstablished += OnConnectionEstablished;

        ConnectedDeviceTextBox.Text = "Connected with Arduino.";

And it works wonderfully and gets connected. And everything is good till now

So because I needed to find all the bluetooth devices available I found following method

            var selector = BluetoothDevice.GetDeviceSelectorFromPairingState(true);
        var devices = await DeviceInformation.FindAllAsync(selector);
        foreach (DeviceInformation device in devices)
        {
            deviceList.Add(device);
        }

This gives me all the paired Bluetooth devices, but the name of Bluetooth module is now HC-05(This is actually the name that windows show in Bluetooth setting and everywhere else). But if I pass this device information to Connection code above it doesn't connect. I tried using device name in

var connection = new BluetoothSerial(selectedDevice.Name);

but it doesn't work, I also tried passing in device itself

var connection = new BluetoothSerial(selectedDevice);

still no luck.

Can someone please explain the name difference and why its not connecting with second method. Thanks in advance.

Answer 1

The first api BluetoothSerial actually operate on RFCOMM device of Bluetooth. You can find its implementation here.

The second api BluetoothDevice actually operate on classical Bluetooth device like Bluetooth headset.

They are implementated different Bluetooth protocol and respectively belongs to Windows.Devices.Bluetooth.Rfcomm and Windows.Devices.Bluetooth namespace in Windows Runtime.

Based on above reason, you pass BluetoothDevice to BluetoothSerial interface and get failure, it is reasonable.

As for the device name, I think since it has different representations in the results of calling two type of device api, so, they are incompatible.

Answer 2

The BluetoothSerial class calls RfcommDeviceService.FromIdAsync(String) where the string represents the RFCOMM service instance (a service).

The BluetoothDevice.FromIdAsync(String) takes a string representing the remote Bluetooth device instance for classic baseband (a device).

If you want the BluetoothDevice from the RfcommDeviceService you use the RfcommDeviceService.Device property.

If you want to find the services for a BluetoothDevice you use the BluetoothDevice.RfcommServices property.