Listen to RFID input device

  • Hello guys on my current project I have to implement a user authentication via RFID reader.

    The user gets an RFID key. The system provides the RFID scanner. When the user want to access the application he/she has to login with his/her RFID key.

    How can I listen to such input device and emit signals on input detection ?
    The RFID reader acts like a keyboard device. You scan the RFID chip and get an ID.

  • Lifetime Qt Champion


    Is it seen like a keyboard or is it a serial device that sends char ?

  • Hi,

    currently it acts like a keyboard.
    What I need is to read the scanner input like a Stream or something like that
    and prevent it from acting like a keyboard.

  • Schneidi,

    As far as I know it isn't possible to reconfigure RFID readers which act like a keyboard to behave in a way that they submit a stream. This problem is well-known, the same problem exists with Barcode scanners which emulate a keyboard. This stuff is just not reliable, and leads to confusion with the "real" keyboard input. You might use keyboard emulated devices when there is no physical keyboard available, but I guess that is rarely the case.

    If you want to read the device input like a stream, you need to use a RFID scanner which is connected as a serial device and is accessible over a system COM port. If you are using COM ports, I highly recommend you to use the QSerialPort class which was introduced with Qt 5.

  • Ok thank you. I guess I have to set up the system in a different way.
    I will do a little research and try to find a solution.

    If I find one I will let you know.

Log in to reply

Looks like your connection to Qt Forum was lost, please wait while we try to reconnect.