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Cannot output a value using QSerialPort

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  • Christian EhrlicherC Offline
    Christian EhrlicherC Offline
    Christian Ehrlicher
    Lifetime Qt Champion
    wrote on last edited by
    #45

    @mrjj said in Cannot output a value using QSerialPort:

    You call setBaudRate, setDataBits etc AFTER you open port. that is wrong.

    I already said this some days ago: https://forum.qt.io/topic/112346/cannot-output-a-value-using-qserialport/23 but it is simply ignored...

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    mrjjM 1 Reply Last reply
    2
    • Christian EhrlicherC Christian Ehrlicher

      @mrjj said in Cannot output a value using QSerialPort:

      You call setBaudRate, setDataBits etc AFTER you open port. that is wrong.

      I already said this some days ago: https://forum.qt.io/topic/112346/cannot-output-a-value-using-qserialport/23 but it is simply ignored...

      mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by
      #46

      @Christian-Ehrlicher
      Indeed and also @jsulm also noted to check open which seems to be forgotten also.

      1 Reply Last reply
      0
      • K Offline
        K Offline
        kuzulis
        Qt Champions 2020
        wrote on last edited by
        #47

        @mrjj said in Cannot output a value using QSerialPort:

        You call setBaudRate, setDataBits etc AFTER you open port. that is wrong.
        must be before open!

        This is not true. You can configure QSP in any time.

        mrjjM Pablo J. RoginaP 2 Replies Last reply
        1
        • K kuzulis

          @mrjj said in Cannot output a value using QSerialPort:

          You call setBaudRate, setDataBits etc AFTER you open port. that is wrong.
          must be before open!

          This is not true. You can configure QSP in any time.

          mrjjM Offline
          mrjjM Offline
          mrjj
          Lifetime Qt Champion
          wrote on last edited by
          #48

          @kuzulis
          Ok
          thank you for clarifying that.
          Over the years I have not had huge success with that without close and reopen the port but its
          good to know QSerialPort does support it :)

          1 Reply Last reply
          0
          • K kuzulis

            @mrjj said in Cannot output a value using QSerialPort:

            You call setBaudRate, setDataBits etc AFTER you open port. that is wrong.
            must be before open!

            This is not true. You can configure QSP in any time.

            Pablo J. RoginaP Offline
            Pablo J. RoginaP Offline
            Pablo J. Rogina
            wrote on last edited by
            #49

            @kuzulis said in Cannot output a value using QSerialPort:

            This is not true. You can configure QSP in any time.

            Are you saying that you can change the settings once a connection has been established?

            Upvote the answer(s) that helped you solve the issue
            Use "Topic Tools" button to mark your post as Solved
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            mrjjM 1 Reply Last reply
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            • Pablo J. RoginaP Pablo J. Rogina

              @kuzulis said in Cannot output a value using QSerialPort:

              This is not true. You can configure QSP in any time.

              Are you saying that you can change the settings once a connection has been established?

              mrjjM Offline
              mrjjM Offline
              mrjj
              Lifetime Qt Champion
              wrote on last edited by
              #50

              @Pablo-J-Rogina

              Yes seems so and he should know as he wrote it :)

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              • K Offline
                K Offline
                kuzulis
                Qt Champions 2020
                wrote on last edited by
                #51

                @Pablo-J-Rogina said in Cannot output a value using QSerialPort:

                Are you saying that you can change the settings once a connection has been established?

                Of course, after open() you can do what you need.

                Pablo J. RoginaP 1 Reply Last reply
                0
                • K kuzulis

                  @Pablo-J-Rogina said in Cannot output a value using QSerialPort:

                  Are you saying that you can change the settings once a connection has been established?

                  Of course, after open() you can do what you need.

                  Pablo J. RoginaP Offline
                  Pablo J. RoginaP Offline
                  Pablo J. Rogina
                  wrote on last edited by
                  #52

                  @kuzulis but changing the settings once you open the port, does impact on the ongoing connection?
                  I mean, does the other side need to update the settings as well? And if so, won't the connection be interrupted?

                  Upvote the answer(s) that helped you solve the issue
                  Use "Topic Tools" button to mark your post as Solved
                  Add screenshots via postimage.org
                  Don't ask support requests via chat/PM. Please use the forum so others can benefit from the solution in the future

                  1 Reply Last reply
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                  • K Offline
                    K Offline
                    kuzulis
                    Qt Champions 2020
                    wrote on last edited by kuzulis
                    #53

                    @Pablo-J-Rogina said in Cannot output a value using QSerialPort:

                    @kuzulis but changing the settings once you open the port, does impact on the ongoing connection?
                    I mean, does the other side need to update the settings as well? And if so, won't the connection be interrupted?

                    The serial communication has no "connection" things. About what "connection" do you speak?

                    PS: In reality (on a low level), any device configurations always changes after a device has been opened! This belongs to any device.

                    Pablo J. RoginaP 1 Reply Last reply
                    0
                    • K kuzulis

                      @Pablo-J-Rogina said in Cannot output a value using QSerialPort:

                      @kuzulis but changing the settings once you open the port, does impact on the ongoing connection?
                      I mean, does the other side need to update the settings as well? And if so, won't the connection be interrupted?

                      The serial communication has no "connection" things. About what "connection" do you speak?

                      PS: In reality (on a low level), any device configurations always changes after a device has been opened! This belongs to any device.

                      Pablo J. RoginaP Offline
                      Pablo J. RoginaP Offline
                      Pablo J. Rogina
                      wrote on last edited by
                      #54

                      @kuzulis said in Cannot output a value using QSerialPort:

                      About what "connection" do you speak?

                      An ongoing transmission

                      Upvote the answer(s) that helped you solve the issue
                      Use "Topic Tools" button to mark your post as Solved
                      Add screenshots via postimage.org
                      Don't ask support requests via chat/PM. Please use the forum so others can benefit from the solution in the future

                      1 Reply Last reply
                      1
                      • K Offline
                        K Offline
                        kuzulis
                        Qt Champions 2020
                        wrote on last edited by kuzulis
                        #55

                        @Pablo-J-Rogina said in Cannot output a value using QSerialPort:

                        An ongoing transmission

                        In this case an ongoing data stream just will be transferred with a new parameters (speed, parity ant etc).

                        1 Reply Last reply
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