@sierdzio Thank you very much!

@SpaceToon said in Unknown Exception is not beeing caught in trycatch-Block (Bluetooth Low Energy, ServiceDetailsDiscovery): @KH-219Design : Thank you very much for your suggestion, for using the lowenergy example from Qt. I did this and the same error occurs there! For this reason, I copied the following code from there and paste it in my .cpp file @SpaceToon I'm truly happy to hear you are able to make forward progress on this! This year marks the first year that I have ventured into BLE using Qt, and I have hit some minor hiccups myself. That is why your post caught my attention in the first place. However, I am working on Android and you are on Windows, which have very different backend/underlying BLE system stacks. So based on the difference in operating systems, I was doubtful if anything I learned would really translate directly here. Your watershed moment about QLowEnergyController::Error prompted me to go look at my code again to see what I am doing in case of QLowEnergyController::Error. I noticed that in my slot I have this comment: // The Qt API for QLowEnergyController has some confusing // overlap/ambiguity. When we get "ConnectionError" I would EXPECT that // the signal QLowEnergyController::disconnected would also be // forthcoming. But it seems (by observation) that this is not how it // works. So we have to treat BOTH the disconnected signal and the // error signal as signs of a disconnection. ... so maybe you and I did actually run into a very similar pitfall after all! It would be great to know if there is some null-reference bug in Qt BLE itself, but neither you nor I may have time to investigate that further. Since we both seem to have worked around our respective pain points, may we carry on and each deliver a successful project! You also asked: Did you compile Qt for debug, and can the debugger see/know the location of the corresponding Qt source files? Which is a very useful tactic, which I have done many times on Linux Qt. I just read some of this: https://stackoverflow.com/questions/5571098/how-can-i-make-msvc-debugger-step-into-qt-library-source-code-again/5576414 Which refers to compiling the QtCored5.dll DLL(s) for oneself. (This is essentially analogous to how I do it on Linux, but building Qt from source is usually several hours of effort on the first time... and I'm not talking about the additional potential hours of just letting the compiler run!) Maybe someone else in this thread has had personal experience with debugging into Qt source files on Microsoft Windows. Or maybe that could be a new thread!

I have exactly the same problem see my topic. Actually I did not find any solution

@TUStudi Ehh. :) well you would on purpose made it so. With the compiler and Qt version you choose to compile app with. THe Qt used would be called UWP  So I would guess on its Not a "Metro" app. But this can also just be something about windows version/patching and not related to you app as all. https://docs.microsoft.com/en-us/answers/questions/3166/what-is-the-meaning-of-this-output-element-not-fou.html

Thank you for your reply. I found this in the documentation: In some cases the peripheral generates value updates which the central is interested in receiving. In order for a characteristic to support such notifications it must have the QLowEnergyCharacteristic::Notify or QLowEnergyCharacteristic::Indicate property and a descriptor of type QBluetoothUuid::ClientCharacteristicConfiguration. Provided those conditions are fulfilled notifications can be enabled as shown in the following code segment: QLowEnergyCharacteristic batteryLevel = service->characteristic( QBluetoothUuid::BatteryLevel); if (!batteryLevel.isValid()) return; QLowEnergyDescriptor notification = batteryLevel.descriptor( QBluetoothUuid::ClientCharacteristicConfiguration); if (!notification.isValid()) return; // establish hook into notifications connect(service, SIGNAL(characteristicChanged(QLowEnergyCharacteristic,QByteArray)), this, SLOT(characteristicChanged(QLowEnergyCharacteristic,QByteArray))); // enable notification service->writeDescriptor(notification, QByteArray::fromHex("0100")); So you were right. But what I do not understand: The writeDescriptor function "Writes newValue as value for descriptor." But what "value" is the QByteArray::fromHex("0100") ? Because when i write the same code for my application and when I call value() on the ClientCharacteristicConfiguration Descriptor from my RX characteristic the output is \x00\x00

Ah ok sorry! Indeed last time I worked with BT it was with older Qt version.

@TUStudi AFAIK writing an MS Excel file is not possible with Qt directly. You need some additional stuff. But writing to a file in general (raw textfile, JSON, XML... etc) is quite easy.

@jsulm Thanks a lot

@harip said in Bluetooth Low Energy: State 'ServiceDiscovered' is never reached: @SpaceToon Is this issue resolved? We are also facing the same issue in Windows 10. As you mentioned, the BLE scanner example is working perfectly fine. Hey, not it is not fixed yet, but a developer is investigating the issue. You can track the current status of the bug here in Jira.

@J-Hilk Thank you, JonB and you were right. For me it actually makes more sense that e.g. at first you connect to the device and then you say "okay, if the signal "connected" is emitted then call the function x.y.". So after changing it, it works now. However, after getting all services and calling "service->discoverDetails" and then "service->characteristics" the characteristics List is empty. After connection is successfull: void Scanner::startServiceDiscovery(){ connect(controller, &QLowEnergyController::discoveryFinished, this, &Scanner::discoveryFinished); controller->discoverServices(); } void Scanner::discoveryFinished(){ qDebug() << "\nService Discovery finished. Following Services found:\n"; QList<QBluetoothUuid> serviceList = controller->services(); for(QBluetoothUuid &sl : serviceList){ qDebug() << controller->createServiceObject(sl)->serviceName() << "Uuid: " << sl; } uartService = controller->createServiceObject(adafruitServiceUuid); qDebug() <<"\nChose the following service: " << (*uartService).serviceName(); connect(uartService, &QLowEnergyService::stateChanged, this, &Scanner::printChars); qDebug() << uartService->state(); //here the state is QLowEnergyService::DiscoveryRequired uartService->discoverDetails(); } void Scanner::printChars(){ qDebug() << uartService->state(); // here the state is now QLowEnergyService::DiscoveringServices const QList<QLowEnergyCharacteristic> chars = uartService->characteristics(); qDebug()<< chars.size(); //however the list size is 0 for (const QLowEnergyCharacteristic &ch : chars) { qDebug() << &ch; } } btw: I know that there is an example for BLE Scanner. But for a project, I want to create an own desktop application which connnects to a peripheral and live plots the data which are received from the sensor with qcustomplot. So I need a QWidget Application because QCustomPlot is a widget...

@martial123 These dongles are needed, if you use the node.js Bluetooth Low Energy library called "noble" (this video is actually about how to use noble), I only linked it because he also explains how to use Zadig. I don't know if your Dongle, that you have know, will work with Qt BluetoothLE library, just try it, if not, you could then try one of these listed in the video .

@SpaceToon said in Dummy backend running. Qt Bluetooth module is non-functional (Bluetooth Low Energy): So is it possible with the MSVC Compiler? No. You will need to build your code for Linux. It is better to do this on a Linux machine as cross compiling from Windows to Linux will be a lot of work. You can have a virtual machine with Linux to build for Linux.

@ivk16 Yes, take a look here: https://bugreports.qt.io/browse/QTBUG-76565

@raven-worx Yes, your are right that it is a little unclear in the term that I had used, I think the term that actually used for BLE pairing is PASSKEY rather than PIN-CODE, but essentially the question stays the same. I have updated original question accordingly. Sorry for not answering on that for too long, but at the end of the day I have finished with using Bluez-Qt library. I had to update it with Low Energy functionality by myself, but it was rather easier for me since I am familiar with Bluez DBus Api. So, AFAIK, the Qt Bluetooth module does not provide any functionality similar to what Bluez's agent provides, i.e. it is not possible to perform general pairing/bonding procedure with different IO (Input-Output) capabilities. Please correct me, if I am wrong.

@J.Hilk Thanks for your answer. But I want to ask how can I know I have to choose one over the another? After running the application "Bluetooth File Transfer" I faced the following error: Thanks in advance!

@elsa Check the kits and see if any red marks.

@HansVL nope, thats conform with my 10.1 experience

You should also use the correct command line prompt for building especially if you start with the one provided by Visual Studio.

@eshirshov Опытным путём выяснилось: соединения отфильтровывались: static const QLatin1String serviceUuid("e8e10f95-1a70-4b27-9ccf-02010264e9c8"); m_discoveryAgent->setUuidFilter(uuid); патч: //m_discoveryAgent->setUuidFilter(uuid);

You're welcome ! I'm pretty sure not all these packages are necessary but at least you have it working now :)

Thank you for your answer. I didn't think this functionnality isn't supported by windows. @SGaist I find indeed your previous answer. I will look this

@NicoFrom13 Hi, Were you able to use this work in progress qtconnectivity? Is it properly working ?

@raven-worx no, sorry, as said in the last post it doens't listen for incoming pairing request. Is the application which has to issue a pairing request! It's quite different. Of course the final result is pretty the same, but I didn't understand how it works from the documentation.

Hi and welcome to devnet, That's a question you might want to bring to the interest mailing list. You'll find there the QtConnectivity module's developers/maintainers. This forum is more user oriented.

Hi, That's a bug that should have been fixed for the next release.

@SGaist Ah right - "configure" is ambiguous due to the two step configuration, once by the configure script for qtbase and once by the qmake for the other modules. This is not so obviously that the summary of the configure script does not warn about disabled features in submodules due to missing dependencies.

Hi, It depends, the 5.7 branch will contain the current work for the next 5.7 release so if you need something that's not in 5.7.0 you should follow 5.7. Otherwise 5.7.0. Note that 5.7.0 is almost out.

@SGaist Hey, thank you. I will try it there.

Then I'd recommend asking this on the interest mailing list. You'll find there the QtBluetooth module maintainers/developers.