Important: Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

Bluetooth low energy, data lost when switch btw applications



  • Hi,
    i created a application to connect and get data stream from our device using BLE 4.1 using newest QT version.
    OS : MacOS 10.15
    it was working fine, no data lost. but when i opened/switched to Chrome (hide the app, it is still get data stream normaly). after that i showed my app , the data lost happened in some first seconds (from when i opened Chrome). i happened every time i do the test.

    i tested on older mac versions, 10.13.... it works fine.
    i would like to ask, is it a issue from QT or MAC OS updated something in 10.15?



  • and 1 more. seem, it happened with Chrome, Safary. i didn't see the issue while using Firefox and some other apps


  • Moderators

    @Pham-Hoang

    how do you get the data? is it a ping-pong exchange or a continuous stream from the BTLE device?

    If the later than that's not unusual. If the OS is busy, you will miss data



  • @J-Hilk it is data streaming.
    if it due to OS busy, it should be has a buffer and resend later, right?
    any what different with 10.15 and older versions?


  • Moderators

    @Pham-Hoang said in Bluetooth low energy, data lost when switch btw applications:

    if it due to OS busy, it should be has a buffer and resend later, right?

    Nope, once the EM-Wave passes by the receiver, it's gone. If it's not detected and recorded.

    any what different with 10.15 and older versions

    I Would assume so, lot's of stuff gets patched, but you would've to go through the patch notes and as those are for general Mac consumers, so the information in there is sparse


Log in to reply