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    • UNSOLVED L2Cap payload size 23 is smaller that the specified size 30 - Qtconnectivity bluetooth error (qt.bluetooth,bluez)
      Mobile and Embedded • bluetooth bluetooth low e bluez qtconnectivity • • Menon  

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    • SOLVED Unknown Exception is not beeing caught in trycatch-Block (Bluetooth Low Energy, ServiceDetailsDiscovery)
      General and Desktop • bluetooth bluetooth low e exceptions • • SpaceToon  

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      @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!
    • UNSOLVED Qt BLE : Bonding and ble security
      General and Desktop • bluetooth low e security low energy bonding • • sfeutrier  

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      See https://bugreports.qt.io/browse/QTBUG-86095 for further informations
    • UNSOLVED What is the purpose of QBluetoothDeviceDiscoveryAgent::setLowEnergyDiscoveryTimeout?
      General and Desktop • linux bluetooth low e ble bluez5 • • pohlondrej.1  

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    • UNSOLVED Bluetooth Low Energy - disconnecting when discovering service details
      General and Desktop • bluetooth bluetooth low e bluez5 lowenergyscanne • • Marc_K  

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      I have exactly the same problem see my topic. Actually I did not find any solution
    • UNSOLVED Bluetooth Low Energy: Resetting serviceState without disconneting from the device
      General and Desktop • bluetooth low e • • SpaceToon  

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    • UNSOLVED Unit/integration tests for Bluetooth Low Energy Application
      General and Desktop • bluetooth low e unit test • • TUStudi  

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    • UNSOLVED BluetoothLowEnergy: Application for connecting to 2 devices with as little duplicate code as possible
      General and Desktop • bluetooth low e best practice • • TUStudi  

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    • SOLVED Writing to the file continuously in Qt (realtime data)?
      General and Desktop • qfile bluetooth low e • • SpaceToon  

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      @mrjj said in Writing to the file continuously in Qt (realtime data)?: @SpaceToon hi Yes you just want to open it once. But i dont see you calling flush anywhere ? Oh, I forgot to paste the flush here, it is actually in my code directly after the write-statement. Thank you very much :)
    • SOLVED Bluetooth low Energy: Sensor Data is split up using QByteArray
      General and Desktop • bluetooth low e containers bytearray sensor readings • • TUStudi  

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      Okay, I have solved the problem with a workaround: In the code for my development board I added a new line character after every value. Then, in my Qt code I check every time the SLOT is called if the value does have a new line char. Either the value is saved in another variable until it receives a value with a new line character or it is output immediately (if it has a new line character). static QString newValue= ""; void MainWindow::updateData(const QLowEnergyCharacteristic &c,const QByteArray &value) { newValue = newValue + (QString)value; if (newValue.contains("\n") || newValue.contains("\r")){ ui->dataList->addItem(newValue.simplified()); ui->dataList->scrollToBottom(); newValue = ""; } }
    • SOLVED Bluetooth Low Energy Heart Game Example - reinterpret_cast?
      General and Desktop • c++ bluetooth low e casting • • TUStudi  

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      Thank you both very much.
    • SOLVED Bluetooth Low Energy: Reading Sensor data in real time after retrieving characteristics
      General and Desktop • bluetooth bluetooth low e • • TUStudi  

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      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
    • UNSOLVED Qt Bluetooth in Windows: QBluetoothDeviceDiscoveryAgent::PoweredOffError not emitted
      General and Desktop • bluetooth bluetooth low e ble bluetoothapis qtbluetooth • • harip  

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      Ah ok sorry! Indeed last time I worked with BT it was with older Qt version.
    • SOLVED Creating BLE & Bluetooth Classic in a single app with live plot?
      General and Desktop • bluetooth bluetooth low e • • TUStudi  

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      @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.
    • UNSOLVED Bluetooth Low Energy: State 'ServiceDiscovered' is never reached
      General and Desktop • signal & slot bluetooth bluetooth low e ble • • SpaceToon  

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      The QTBluetooth Central API is not supported on any platform. see the first table in Qt Bluetooth
    • SOLVED Bluetooth Low Energy Scanner: Discover Service Details
      General and Desktop • bluetooth low e ble scanner • • SpaceToon  

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      i had same error in my project. this page helped me -> https://forum.qt.io/topic/117241/why-qlowenergyservice-unknownerror/2 i have changed my code from connect(controller, &QLowEnergyController::discoveryFinished, this, &Device::serviceScanDone); to connect(controller, &QLowEnergyController::discoveryFinished, this, &Device::serviceScanDone,Qt::QueuedConnection); and problem disappeared.
    • SOLVED Lowenergyscanner Exampler: "Error occured when trying to connect to remote device."
      General and Desktop • bluetooth bluetooth low e lowenergyscanne • • SpaceToon  

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      @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 .
    • SOLVED Bluetooth LE performance in different platforms
      General and Desktop • bluetooth low e ibeacon • • RickS  

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      Thank you very much for your reply. @sierdzio said in Bluetooth LE performance in different platforms: Is the simulated beacon paired in Windows Bluetooth settings? Without it, Qt will not detect it! (this will be fixed in Qt 5.14 I think)., Unfortunately, Windows does not allow me to pair the simulated iBeacon since it does not appear in the available Bluetooth devices list from the control panel. @sierdzio said in Bluetooth LE performance in different platforms: Also, make sure you're using the newest Windows version with all updates. Unfortunately, Bluetooth support on Windows is quite bad, has memory leaks etc. In early Windows 10 builds it was barely working at all. Sure, it is the latest Windows version with all updates. I was also trying to compile the Qt 5.15 source available in the repo to enable the win32 Bluetooth API to see if it makes any difference but I wasn't able to compile it... But this was just a curiosity. For me it's OK to consider Windows as the least compatible platform for the moment. About Android, I was able to tune the application and now it can properly detect the simulated iBeacon. I was using the Bluetooth LE scanner example but I hadn't checked the manifest file so that was probably the issue.
    • SOLVED Dummy backend running. Qt Bluetooth module is non-functional (Bluetooth Low Energy)
      General and Desktop • bluetooth bluetooth low e • • SpaceToon  

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      @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.
    • UNSOLVED Change advertisingdata QLowEnergyController
      General and Desktop • bluetooth bluetooth low e • • Crindu  

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    • UNSOLVED Adafruit BLE UART problem
      Mobile and Embedded • raspberry pi 3 bluetooth low e • • Kutyus  

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      I tested it with Qt 5.11.0, but more deficiency detected. The General Attribute also undetected and characteristic write is not working :(
    • SOLVED Bluetooth with Windows ? (Bluetooth Low Energy)
      3rd Party Software • windows bluetooth bluetooth low e windows 10 iot • • NicoFrom13  

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      @NicoFrom13 Hi, Were you able to use this work in progress qtconnectivity? Is it properly working ?
    • SOLVED Bluetoothapis.h windows SDK - Issue
      3rd Party Software • bluetooth low e windows sdk bluetoothapis • • NicoFrom13  

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      Awesome man. That show me that sometimes ask the question is more usefull than searching for hours.... I didn't know that i could not use Windows SDK with MinGW i understand now. windows SDK needs to be with Visual compiler ... Many thanks have a nice Day.
    • SOLVED Regarding the BLE heart listener sample code
      QML and Qt Quick • bluetooth low e qt5.5.1 • • user_edu  

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      Hi and welcome to devnet, Glad you found out and thanks for sharing. Since you have ti working now please mark the thread as solved using the "Topic Tools" button so that other forum uses may know a solution has been found :)
    • UNSOLVED GATT server definition
      General and Desktop • bluetooth bluetooth low e ble • • Mark81  

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    • UNSOLVED How to receive Apple Notifications
      General and Desktop • bluetooth bluetooth low e ble apple push notificati • • Mark81  

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      Then I'd recommend asking this on the interest mailing list. You'll find there the QtBluetooth module maintainers/developers.
    • UNSOLVED Strange Error in qtandroid BLE Example (LowEnergyScanner)
      Mobile and Embedded • android bluetooth low e ble qt5.5.1 • • raosaif  

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    • UNSOLVED How do I scan for specific BLE service UUIDs
      Mobile and Embedded • bluetooth bluetooth low e ble uuid btle • • ulso  

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      Hi, There might just be not much people on this forum that use the QtBluetooth module. In that case, there's always the interest mailing list where you can find Qt's developers/maintainers.
    • UNSOLVED Bluetooth Low Energy Characteristic Indications (not Notifications)
      General and Desktop • bluetooth low e indications • • ZSoft  

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      a little bit late but for anybody searching. Indication is different than notification in that there is a confirmation that data sent from peripherical (hardware measuring device as heart rate) to the central device (same as your phone app) reached. Notification does not offer this confirmation. It is something like udp (no confiramtion available) and http (confirmation available)
    • UNSOLVED QBluetoothDeviceDiscoveryAgent::UnsupportedPlatformError on BeagleBone Black with BTLE
      Mobile and Embedded • linux arm bluetooth low e beaglebone bbb • • ZSoft  

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    • UNSOLVED Qt 5.5.1 Android 5.0.1 Bluetooth Low Energy Example won´t work
      Mobile and Embedded • bluetooth low e example android 5 • • mrnosie  

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      I know this question is old, but it seems noone is answering BLE related questions here. (I've just posted such a question myself, and fear noone will anwer it either). I developed an app based on the same example, and it worked fine under both android 4.3.2, 5.1.2, and 6.0. However, the customer came with an android 5.01, and sure enough, the app did not work as expected. It seemed to "hang" and tried to connect to two devices at the same time, etc. We did not investigate it further. This was with Qt 5.6, so the issue is not resolved, and may never be, since with newer versions of Android it is working fine.
    • UNSOLVED Full Windows 10 support
      General and Desktop • windows 10 bluetooth low e qt 5.6 • • Jan Roorda  

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      Hi, There's a WIP branch in the qtbluetooth module for Windows, you can check the state there.
    • UNSOLVED Does Qt support Bluetooth Low Energy under Windows 10?
      General and Desktop • windows 10 bluetooth low e qt 5.5.1 • • Jan Roorda  

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      @kuzulis Thanks!
    • BLE demos fail on Android
      Mobile and Embedded • android bluetooth low e • • pbljung  

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      @pbljung said in BLE demos fail on Android: errorReceived these errors can happen see my comments on top of void MyBluetoothDeviceInfo::onControllerError(QLowEnergyController::Error error) in https://github.com/ekke/ekkesBTLEexample/blob/master/cpp/bt/mybluetoothdeviceinfo.cpp not only 133 (reported as unhandled error) also 34 and 8 can happen see also all the discussions at https://bugreports.qt.io/browse/QTBUG-31674 per ex from my comment on 133: while developing new example app for BT LE and Qt 5.8 using QtQuickControls2 for Android, iOS I also run into GATT ERROR 133 googled and found out that this bug iseems not to be a Qt Bug. some more infos here: https://github.com/NordicSemiconductor/Android-nRF-Toolbox/issues/9 https://android.googlesource.com/platform/external/bluetooth/bluedroid/+/android-5.1.1_r13/stack/include/gatt_api.h of course would be great if Qt could handle error 133 my workaround: if getting a QLowEnergyController::ConnectionError I try to reconnect up to 5 times with a delay of 1000ms In most cases 2nd or 3rd retry will connect without the error. BTW: find out more on my new BTLE Example APP: http://bit.ly/ekkeBTLEapp
    • Clear Android Bluetooth cache
      Mobile and Embedded • android bluetooth bluetooth low e • • JRoorda  

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      Maybe you should just do bluetooth turn off/on programmaticaly from your app, before using of an BLE.
    • Qt Bluetooth stack performance
      Mobile and Embedded • android bluetooth bluetooth low e performance ble discovery agent low energy cont • • JRoorda  

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    • Bluetooth LE QT5.5 Windows 10 LowEnergyScanner HeartListener UnsupportedPlatformError
      General and Desktop • qt5.5 windows 10 bluetooth low e • • Karel  

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      A BTLE port towards WinRT is currently going on and we hope to have it supported with Qt 5.8. Please note that this does not include classic / desktop Windows, as the APIset is not available for this platform.
    • Qt Bluetooth File Transfer (or even message sending)
      Mobile and Embedded • android bluetooth qt 5.5 bluetooth low e • • Niranjan Jayanth  

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    • Bluetooth Low Energy on iOS
      Mobile and Embedded • ios bluetooth low e 5.5 • • csanders  

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      @csanders Bump this. I've got the same issue. Anyone at Qt able to shed some light on why it's so difficult to perform these features on iOS? I'm assuming it's something to do with Apple's MFi?
    • Is it possible to simulate a bluetooth low energy device on mac or linux with Qt 5.5 Beta ?
      General and Desktop • bluetooth bluetooth low e • • lunatic fringe  

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      Thx, i will give it a try