Build an application which uses Windows.Devices.Bluetooth.dll

Hi, I'm developing an application which uses Windows' BLE support. The application is really simple, it implements a class for using BLE (here is a part of the code):

Code (CSharp):

1. [...]
2. using Windows.Devices.Bluetooth.Advertisement;
3. using Windows.Devices.Enumeration;
4. using Windows.Devices.Bluetooth;
5. using Windows.Devices.Bluetooth.GenericAttributeProfile;
6. using Windows.Storage.Streams;
7.  
8. [...]
9. namespace Ble {
10.  
11.     class BleDevice {
12.  
13.         BluetoothLEDevice btdev;
14.  
15.         public BlebDevice(string addr, int freq=100, string logfile="") {
16.             string[] requestedProperties = { "System.Devices.Aep.DeviceAddress", "System.Devices.Aep.IsConnected" };
17.             DeviceWatcher deviceWatcher = DeviceInformation.CreateWatcher(
18.                 BluetoothLEDevice.GetDeviceSelectorFromPairingState(false),
19.                 requestedProperties,
20.                 DeviceInformationKind.AssociationEndpoint);
21.             deviceWatcher.Added += DeviceWatcher_Added;
22.             deviceWatcher.Updated += DeviceWatcher_Updated;
23.             deviceWatcher.Removed += DeviceWatcher_Removed;
24.             deviceWatcher.Start();
25.  
26.         private async void DeviceWatcher_Added(DeviceWatcher sender, DeviceInformation args) {
27.             btdev = await BluetoothLEDevice.FromIdAsync(args.Id);
28.             GattDeviceServicesResult result = await btdev.GetGattServicesAsync();
29.             Guid customGuid = new Guid("xxx");
30.             foreach (GattDeviceService service in result.Services) {
31.                 if (customGuid == service.Uuid) {
32.                     GattCharacteristicsResult cresult = await service.GetCharacteristicsAsync();
33.                     GattCharacteristic ch = cresult.Characteristics[0];
34.                     await ch.WriteClientCharacteristicConfigurationDescriptorAsync(GattClientCharacteristicConfigurationDescriptorValue.Notify);
35.                     ch.ValueChanged += Characteristic_ValueChanged;
36.                 }
37.             }
38.         }
39.  
40.         void Characteristic_ValueChanged(GattCharacteristic sender, GattValueChangedEventArgs args) {
41.             DataReader reader = DataReader.FromBuffer(args.CharacteristicValue);
42.             byte[] input = new byte[reader.UnconsumedBufferLength];
43.             reader.ReadBytes(input);
44.             [...]
45.         }
46.  
47.         private async void DeviceWatcher_Removed(DeviceWatcher sender, DeviceInformationUpdate args) { }
48.  
49.         private async void DeviceWatcher_Updated(DeviceWatcher sender, DeviceInformationUpdate args) { }
50.  
51.     }
52. }

The project uses IL2CPP as scripting backend. I can create the UWP build successfully, and when I build the solution with Visual Studio, it correctly compiles. The problem is that I get several issues at runtime, and BLE is not working, e.g.

Code (plain):

1. onecoreuap\drivers\wdm\bluetooth\user\winrt\common\devquerydevpropprovider.cpp(297)\Windows.Devices.Bluetooth.dll!00007FFFA4CCB4F1: (caller: 00007FFFA4CCAFC6) ReturnHr(1) tid(974) 80070490 Element not found.
2. onecoreuap\drivers\wdm\bluetooth\user\winrt\common\devquerydevpropprovider.cpp(131)\Windows.Devices.Bluetooth.dll!00007FFFA4CCB01A: (caller: 00007FFFA4CDEFE8) ReturnHr(3) tid(974) 80070490 Element not found.
3. onecoreuap\drivers\wdm\bluetooth\user\winrt\device\bluetoothledevice.cpp(1417)\Windows.Devices.Bluetooth.dll!00007FFFA4CDF000: (caller: 00007FFFA4CE9591) LogHr(1) tid(974) 80070490 Element not found.
4. onecoreuap\drivers\wdm\bluetooth\user\winrt\common\devquerydevpropprovider.cpp(297)\Windows.Devices.Bluetooth.dll!00007FFFA4CCB4F1: (caller: 00007FFFA4CCAFC6) ReturnHr(2) tid(56c) 80070490 Element not found.
5. onecoreuap\drivers\wdm\bluetooth\user\winrt\common\devquerydevpropprovider.cpp(131)\Windows.Devices.Bluetooth.dll!00007FFFA4CCB01A: (caller: 00007FFFA4CDEFE8) ReturnHr(4) tid(56c) 80070490 Element not found.
6. onecoreuap\drivers\wdm\bluetooth\user\winrt\device\bluetoothledevice.cpp(1417)\Windows.Devices.Bluetooth.dll!00007FFFA4CDF000: (caller: 00007FFFA4CE9591) LogHr(2) tid(56c) 80070490 Element not found.
7. [...]
8. onecoreuap\drivers\wdm\bluetooth\user\winrt\common\devquerydevpropprovider.cpp(297)\Windows.Devices.Bluetooth.dll!00007FFFA4CCB4F1: (caller: 00007FFFA4CCAFC6) ReturnHr(5) tid(2e84) 80070490 Element not found.
9. onecoreuap\drivers\wdm\bluetooth\user\winrt\common\devquerydevpropprovider.cpp(131)\Windows.Devices.Bluetooth.dll!00007FFFA4CCB01A: (caller: 00007FFFA4CDEFE8) ReturnHr(6) tid(2e84) 80070490 Element not found.
10. onecoreuap\drivers\wdm\bluetooth\user\winrt\device\bluetoothledevice.cpp(1417)\Windows.Devices.Bluetooth.dll!00007FFFA4CDF000: (caller: 00007FFFA4CE9591) LogHr(3) tid(2e84) 80070490 Element not found.
11.  

When I use the same code in isolation (i.e. in a Visual Studio project which doesn't use Unity) it correctly works: I can use BLE devices correctly.

The entire log is attached. How can I get rid of these errors? Thank you very much!

 

Sure, I've reported it, thank you very much!

Unfortunately, I've to write BLE instructions inside preprocessor directives #if !UNITY_EDITOR since they don't work in the editor. So, when I debug them, they're skipped.

Yes.

No, there aren't errors in the .NET project.

Thank you!

 

1088764

Oh, sorry. The problem is that when I try to attach the debugger I can see only Editor's process and not Player's one. In the project settings I've enabled: Development Build, Script Debugging and Wait For Managed Debugger (and actually I can see the waiting dialog when the application starts).

 

Oh thanks, now I can debug it. Here is what happens. In my non-Unity application, when I debug its C# code, the debugger correctly process this instruction (doing a step by step debug):

btdev = await BluetoothLEDevice.FromIdAsync(args.Id);

and goes to the next instruction. When I debug the same line in the Unity application, Visual Studio shows the following error:

Frame not in module. The current stack frame was not found in a loaded module.

and I get the following error in the output:

The thread 0x647b8980 has exited with code 0 (0x0).

Thank you!

 

Hey was it fixed, because it doesn't seem to work for me, unless it's something else that makes my thing fail.

 

Hey, I think I found my issue, I was using "#if NETFX_CORE" around my code in order to make it work in the editor, but I guess since the backend is il2cpp it doesn't work for that, so i'm gonna try to replace my NETFX_CORE with WINDOWS_UWP like this dude suggested : https://forums.hololens.com/discussion/3217/enabling-ble-in-hololens-app and then I'll see if it works and I'll get back to you.

 

Yes thank you, the bluetooth now works.

 

Hi

I am facing the exact same issue in Hololens 1, Can you help me with that. Below is my code for accessing Bluetooth in Unity. I can build the project but after deploying it to Hololens 1 visual studio is giving me following errors.


'Yamaha MR AVPRO.exe' (Win32): Loaded 'C:\Windows\System32\Windows.Devices.Bluetooth.dll'. Symbols loaded.
'Yamaha MR AVPRO.exe' (Win32): Loaded 'C:\Windows\System32\Windows.Networking.dll'. Symbols loaded.
'Yamaha MR AVPRO.exe' (Win32): Loaded 'C:\Windows\System32\FirewallAPI.dll'. Symbols loaded.
'Yamaha MR AVPRO.exe' (Win32): Loaded 'C:\Windows\System32\fwbase.dll'. Symbols loaded.
'Yamaha MR AVPRO.exe' (Win32): Loaded 'C:\Windows\System32\Windows.Internal.Bluetooth.dll'. Symbols loaded.
'Yamaha MR AVPRO.exe' (Win32): Loaded 'C:\Windows\System32\deviceaccess.dll'. Symbols loaded.
onecoreuap\drivers\wdm\bluetooth\user\winrt\common\devicehandle.cpp(117)\Windows.Devices.Bluetooth.dll!61C94C0D: (caller: 61C952C9) Exception(1) tid(10c0) 80070005 Access is denied.
Exception thrown at 0x77062DE2 in Yamaha MR AVPRO.exe: Microsoft C++ exception: wil::ResultException at memory location 0x00E8E360.
Exception thrown at 0x77062DE2 in Yamaha MR AVPRO.exe: Microsoft C++ exception: [rethrow] at memory location 0x00000000.
onecoreuap\drivers\wdm\bluetooth\user\winrt\advertisement\bluetoothleadvertisementwatcher.cpp(1510)\Windows.Devices.Bluetooth.dll!61C73426: (caller: 61C74CC2) Exception(2) tid(10c0) 80070005 Access is denied.
Exception thrown at 0x77062DE2 in Yamaha MR AVPRO.exe: Microsoft C++ exception: wil::ResultException at memory location 0x00E8E418.
Exception thrown at 0x77062DE2 in Yamaha MR AVPRO.exe: Microsoft C++ exception: [rethrow] at memory location 0x00000000.
The thread 0x1058 has exited with code 0 (0x0).

 

Hello,
I am trying to create a game which uses a bluetooth device to capture the heart rate of the player. I have created a WPF library with the code needed to connect to the bluetooth device and receive the values, however, I am not sure how to use it in my Unity project.

Since the library uses windows namespaces, iIhad to disable the dll for the editor and leave it only for WSAPlayer and standalone, now I am not sure how to reference the namespace of this library in my code and how to call the functions and receive values from it to be used in my project.

I tried wrapping the code inside #if NETFX_CORE and #if ENABLE_WINMD_SUPPORT and even #if WINDOWS_UWP, how am I to debug if the connections and everything is working?

Any help would be appreciated, thank you!

 

Is there somewhere we can go to learn about accessing bluetooth information from the system ex Windows.Devices.Bluetooth within Unity? Seems a little crazy that Unity doesnt have something for talking to PC based bluetooth devices.