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QSerialPort on Mac OS X 10.9: 921600 baudrate is not set

  • It seems that custom baud rate feature (e.g. 921600) does not work on Mac OS X 10.9. I use ZOC terminal emulator and it works when setting 921600 baud rate on a USB-UART bridge (FT232X). Whereas QSerialPort does not return any error when setting 921600, but it reads weird characters. Setting it to 115200 works.

    Any clues ?

  • Qt Champions 2020

    Hmm.. The speed 921600 is not a custom - it is standard speed..

    In your case you can open the source of the QtSerialPort project from the QtCreator on your Mac PC. And then look on the highlighting of:

    #ifdef B921600
    baudRateMap.insert(921600, B921600);

    in file "qserialport_unix.cpp".

    If a macro B921600 exists then its highlighting (block of code) will be active. In this case all should be fine.

    In other case - need to do debugging.

    PS: Also I pay attention that setup the speed need to do only after opening of device! At least on the version of Qt is 5.2.2. Though, it is already fixed for the future release:,79656

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