0 Replies Latest reply on Sep 11, 2018 4:26 AM by Alexander Karelin

    MC319Z: Unable to open connection to reader

    Alexander Karelin



      I'm developing a simple application for MC319Z RFID reader using Visual Studio 2008 and EMDK v2.9.


      I refer the EMDK Programmer's Guide in order to work with RFID.


      The following code is used, just three strings:


      string hostname = "";

      RFIDReader rfid3 = new RFIDReader(hostname, 0, 0);



      I know the RFIDReader class uses the LLRP service running on the device.

      It's configured by default:


      Port: 5084


      Unfortunately I get an exception after the "Connect" method call:


           Exception occured: Symbol.RFID3.OperationFailureException: Connect

           at Symbol.RFID3.ProcessErrorCode.ThrowException(IntPtr readerHandle, String sMessage, RFIDResults results, Boolean      getLastError)

           at Symbol.RFID3.RFIDReader.Connect()

           Status: Unable to open connection to reader


      The in-built demo app works stable.

      It seems the LLRP service is busy.

      I stopped and started RFID (the icon on the home screen indicates the "running" state), closed all the 3d party apps running in the background but I still can't access the reader.


      How can I get rid of this problem?

      Could you provide me some way to debug this issue, please?

      Thank you.