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Multi serial port application

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  • V Offline
    V Offline
    veera
    wrote on last edited by
    #25

    permission is denied error while opening the port in Terminal Sample...

    jsulmJ 1 Reply Last reply
    0
    • V veera

      permission is denied error while opening the port in Terminal Sample...

      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by
      #26

      @veera What does

      ls -lh /dev/ttyS4
      

      say?

      https://forum.qt.io/topic/113070/qt-code-of-conduct

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      1
      • mrdebugM Offline
        mrdebugM Offline
        mrdebug
        wrote on last edited by
        #27

        Are you in dialout group?

        Need programmers to hire?
        www.labcsp.com
        www.denisgottardello.it
        GMT+1
        Skype: mrdebug

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        • V Offline
          V Offline
          veera
          wrote on last edited by
          #28

          i tried using this command on the qt project path also not able to open the serial ports.....

          1 Reply Last reply
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          • V Offline
            V Offline
            veera
            wrote on last edited by
            #29

            yes i am in dialout group....

            1 Reply Last reply
            0
            • V Offline
              V Offline
              veera
              wrote on last edited by
              #30

              crw-rw---- 1 root dialout 4, 68 Dec 11 13:22 /dev/ttyS4

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              • V Offline
                V Offline
                veera
                wrote on last edited by
                #31

                @jsulm said in multi serial port application:

                ls -lh /dev/ttyS4

                crw-rw---- 1 root dialout 4, 68 Dec 11 13:22 /dev/ttyS4

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                • mrdebugM Offline
                  mrdebugM Offline
                  mrdebug
                  wrote on last edited by
                  #32

                  Are you sure you really have 4 serial ports? Which kind of machine have you got?
                  In some case, with a beaglebone board for example, you have to enable the third and fourth serial port with a special kernel parameter.

                  Need programmers to hire?
                  www.labcsp.com
                  www.denisgottardello.it
                  GMT+1
                  Skype: mrdebug

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                  • mrjjM Offline
                    mrjjM Offline
                    mrjj
                    Lifetime Qt Champion
                    wrote on last edited by
                    #33

                    Hi
                    Often you have to add your user to the dialout group to be allowed to use it

                    usermod -a -G dialout MY_USER_NAME

                    as @mrdebug asks/says

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                    • V Offline
                      V Offline
                      veera
                      wrote on last edited by
                      #34

                      @mrdebug
                      I have only two serial ports i am connecting slot machine to my desktop computer.....need to connect from desktop to slot machine i am struggling to open the serial port please help me i have added like this

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                      • V Offline
                        V Offline
                        veera
                        wrote on last edited by
                        #35

                        sudo usermod -a -G dialout veera

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                        0
                        • V Offline
                          V Offline
                          veera
                          wrote on last edited by
                          #36

                          in my desktop using two serial ports using right now may be in built its four i guess.....

                          jsulmJ 1 Reply Last reply
                          0
                          • V veera

                            in my desktop using two serial ports using right now may be in built its four i guess.....

                            jsulmJ Offline
                            jsulmJ Offline
                            jsulm
                            Lifetime Qt Champion
                            wrote on last edited by
                            #37

                            @veera Make sure your user is member of dialout group

                            https://forum.qt.io/topic/113070/qt-code-of-conduct

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                            1
                            • mrjjM Offline
                              mrjjM Offline
                              mrjj
                              Lifetime Qt Champion
                              wrote on last edited by
                              #38

                              Also if you are having ONLY 2 serial ports why are you then
                              trying the /dev/ttyS4 port ???
                              i would giess on
                              /dev/ttyS0
                              or
                              /dev/ttyS1

                              1 Reply Last reply
                              0
                              • V Offline
                                V Offline
                                veera
                                wrote on last edited by
                                #39

                                i have verified with minicom slot machine cable is connected with ttyS4 so i am trying with this port

                                1 Reply Last reply
                                0
                                • V Offline
                                  V Offline
                                  veera
                                  wrote on last edited by
                                  #40

                                  i have tried ttyS0 and ttyS1 also it is not able to open the serial port....

                                  mrjjM 1 Reply Last reply
                                  0
                                  • V veera

                                    i have tried ttyS0 and ttyS1 also it is not able to open the serial port....

                                    mrjjM Offline
                                    mrjjM Offline
                                    mrjj
                                    Lifetime Qt Champion
                                    wrote on last edited by mrjj
                                    #41

                                    @veera

                                    ok. not sure what could be wrong with your linux if you have added
                                    yourself (your username) to dial out group and you are sure that the port exists.

                                    What linux are you using ?

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                                    0
                                    • V Offline
                                      V Offline
                                      veera
                                      wrote on last edited by
                                      #42

                                      ubuntu 16.04 LTS ,i opened serial port now if i choose the run in terminal its opening please help how to set sudo password in qt instead of choosing run in terminal directly need to open

                                      aha_1980A 1 Reply Last reply
                                      0
                                      • V veera

                                        ubuntu 16.04 LTS ,i opened serial port now if i choose the run in terminal its opening please help how to set sudo password in qt instead of choosing run in terminal directly need to open

                                        aha_1980A Offline
                                        aha_1980A Offline
                                        aha_1980
                                        Lifetime Qt Champion
                                        wrote on last edited by
                                        #43

                                        @veera said in multi serial port application:

                                        ubuntu 16.04 LTS ,i opened serial port now if i choose the run in terminal its opening please help how to set sudo password in qt instead of choosing run in terminal directly need to open

                                        If you need the sudo password than setting yourself into dialout group did not work!

                                        Have your rebooted your PC after you put yourself into dialout?

                                        Hint: call error() when opening the serial port fails to get more information about the error.

                                        Qt has to stay free or it will die.

                                        jsulmJ 1 Reply Last reply
                                        2
                                        • aha_1980A aha_1980

                                          @veera said in multi serial port application:

                                          ubuntu 16.04 LTS ,i opened serial port now if i choose the run in terminal its opening please help how to set sudo password in qt instead of choosing run in terminal directly need to open

                                          If you need the sudo password than setting yourself into dialout group did not work!

                                          Have your rebooted your PC after you put yourself into dialout?

                                          Hint: call error() when opening the serial port fails to get more information about the error.

                                          jsulmJ Offline
                                          jsulmJ Offline
                                          jsulm
                                          Lifetime Qt Champion
                                          wrote on last edited by
                                          #44

                                          @aha_1980 @veera Reboot is not needed: just log off and on again after adding yourself to the group.

                                          https://forum.qt.io/topic/113070/qt-code-of-conduct

                                          aha_1980A 1 Reply Last reply
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