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PWM Servo IO Board

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  • Eric KatzfeyE Eric Katzfey

    @valvarez That is the IO board. Yes, that's part of what I was talking about. Perhaps I don't quite understand your question. I would suggest creating a wiring diagram of your proposed system and including that in this thread. We can take a look and see if looks feasible. What you are proposing is a customization to the platform that we have never attempted so the best we can do is to take a look at your proposed design and provide some feedback on it.

    V Offline
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    valvarez
    Contributor
    wrote on last edited by
    #10

    @Eric-Katzfey I think it has to do with this: https://forum.modalai.com/topic/1826/voxl-2-i-o-and-gps
    Is it possible to connect the IO Board in parallel with the GPS connection?

    Eric KatzfeyE 1 Reply Last reply
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    • V valvarez

      @Eric-Katzfey I think it has to do with this: https://forum.modalai.com/topic/1826/voxl-2-i-o-and-gps
      Is it possible to connect the IO Board in parallel with the GPS connection?

      Eric KatzfeyE Offline
      Eric KatzfeyE Offline
      Eric Katzfey
      ModalAI Team
      wrote on last edited by
      #11

      @valvarez No, you cannot connect two separate devices to the same UART.

      1 Reply Last reply
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      • Eric KatzfeyE Eric Katzfey

        @valvarez The IO board was created to allow builders of custom drones who need to use PWM ESCs and / or SBUS RC units to be able to connect to a VOXL 2 which has neither PWM nor the ability to configure UARTs for SBUS. So, for example, if you wanted to use PWM ESCs instead of our UART based ESC then you would attach the IO board to the UART that normally is connected to the ESC. Or, for RC, you would connect (as in that diagram) to the UART that normally is connected to an RC receiver. If you still want to use our ESC, the current RC and GPS then you don't have a spare UART for the IO board. One possible way to do this would be to move the GPS from it's current connector to a UART on the applications processor side and then attach the IO board to the UART that has the GPS now. This would require an add-on board that exposes such a UART.

        V Offline
        V Offline
        valvarez
        Contributor
        wrote on last edited by
        #12
        This post is deleted!
        1 Reply Last reply
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        • Eric KatzfeyE Eric Katzfey

          @valvarez The IO board was created to allow builders of custom drones who need to use PWM ESCs and / or SBUS RC units to be able to connect to a VOXL 2 which has neither PWM nor the ability to configure UARTs for SBUS. So, for example, if you wanted to use PWM ESCs instead of our UART based ESC then you would attach the IO board to the UART that normally is connected to the ESC. Or, for RC, you would connect (as in that diagram) to the UART that normally is connected to an RC receiver. If you still want to use our ESC, the current RC and GPS then you don't have a spare UART for the IO board. One possible way to do this would be to move the GPS from it's current connector to a UART on the applications processor side and then attach the IO board to the UART that has the GPS now. This would require an add-on board that exposes such a UART.

          V Offline
          V Offline
          valvarez
          Contributor
          wrote on last edited by
          #13

          @Eric-Katzfey said in PWM Servo IO Board:

          @valvarez The IO board was created to allow builders of custom drones who need to use PWM ESCs and / or SBUS RC units to be able to connect to a VOXL 2 which has neither PWM nor the ability to configure UARTs for SBUS. So, for example, if you wanted to use PWM ESCs instead of our UART based ESC then you would attach the IO board to the UART that normally is connected to the ESC. Or, for RC, you would connect (as in that diagram) to the UART that normally is connected to an RC receiver. If you still want to use our ESC, the current RC and GPS then you don't have a spare UART for the IO board. One possible way to do this would be to move the GPS from it's current connector to a UART on the applications processor side and then attach the IO board to the UART that has the GPS now. This would require an add-on board that exposes such a UART.

          Understood. And could you give me the reference of the add-on board to expose that UART?

          Eric KatzfeyE 1 Reply Last reply
          0
          • V valvarez

            @Eric-Katzfey said in PWM Servo IO Board:

            @valvarez The IO board was created to allow builders of custom drones who need to use PWM ESCs and / or SBUS RC units to be able to connect to a VOXL 2 which has neither PWM nor the ability to configure UARTs for SBUS. So, for example, if you wanted to use PWM ESCs instead of our UART based ESC then you would attach the IO board to the UART that normally is connected to the ESC. Or, for RC, you would connect (as in that diagram) to the UART that normally is connected to an RC receiver. If you still want to use our ESC, the current RC and GPS then you don't have a spare UART for the IO board. One possible way to do this would be to move the GPS from it's current connector to a UART on the applications processor side and then attach the IO board to the UART that has the GPS now. This would require an add-on board that exposes such a UART.

            Understood. And could you give me the reference of the add-on board to expose that UART?

            Eric KatzfeyE Offline
            Eric KatzfeyE Offline
            Eric Katzfey
            ModalAI Team
            wrote on last edited by
            #14

            @valvarez Some examples include: https://www.modalai.com/collections/expansion-board/products/m0151?variant=47083939791152 and https://www.modalai.com/products/m0141?variant=46829445513520

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            • Eric KatzfeyE Eric Katzfey

              @valvarez Some examples include: https://www.modalai.com/collections/expansion-board/products/m0151?variant=47083939791152 and https://www.modalai.com/products/m0141?variant=46829445513520

              V Offline
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              valvarez
              Contributor
              wrote on last edited by
              #15

              @Eric-Katzfey I already understood what you mean. What if that connector to which we connect the board that exposes the UART is occupied by the Sierra 5G Modem?
              https://www.modalai.com/products/mdk-m0090?variant=40594936463411
              I see in the datasheet that the J9 connector is a UART/i2c. Could the GPS be connected here to free it from the VOXL 2?
              I'm starting to see the light...
              Thanks @Eric-Katzfey 🙏

              modaltbM 1 Reply Last reply
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              • V valvarez

                @Eric-Katzfey I already understood what you mean. What if that connector to which we connect the board that exposes the UART is occupied by the Sierra 5G Modem?
                https://www.modalai.com/products/mdk-m0090?variant=40594936463411
                I see in the datasheet that the J9 connector is a UART/i2c. Could the GPS be connected here to free it from the VOXL 2?
                I'm starting to see the light...
                Thanks @Eric-Katzfey 🙏

                modaltbM Offline
                modaltbM Offline
                modaltb
                ModalAI Team
                wrote on last edited by
                #16

                @valvarez

                A bit hidden but it's /dev/ttyHS2

                https://docs.modalai.com/voxl2-linux-user-guide/#devttyhs2---hsb2b-connector-uart

                We ship a little helper tool that you can do a loop back test real quick if you make a cable that shorts pins 2/3:

                qrb5165io-uart-test -d /dev/ttyHS2
                
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                • modaltbM modaltb

                  @valvarez

                  A bit hidden but it's /dev/ttyHS2

                  https://docs.modalai.com/voxl2-linux-user-guide/#devttyhs2---hsb2b-connector-uart

                  We ship a little helper tool that you can do a loop back test real quick if you make a cable that shorts pins 2/3:

                  qrb5165io-uart-test -d /dev/ttyHS2
                  
                  V Offline
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                  valvarez
                  Contributor
                  wrote on last edited by
                  #17

                  @modaltb I don't think what you're telling me is useful to me, or I haven't understood you correctly.
                  That connector that you tell me is occupied by the M0090 -5g Add-on board, since it is a Sentinel with 5G.
                  My question is if there is a connector in that add-on to put the GPS and thus free up the VOXL connector where the IO Board will be connected.

                  tomT 1 Reply Last reply
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                  • V valvarez

                    @modaltb I don't think what you're telling me is useful to me, or I haven't understood you correctly.
                    That connector that you tell me is occupied by the M0090 -5g Add-on board, since it is a Sentinel with 5G.
                    My question is if there is a connector in that add-on to put the GPS and thus free up the VOXL connector where the IO Board will be connected.

                    tomT Offline
                    tomT Offline
                    tom
                    admin
                    wrote on last edited by
                    #18

                    @valvarez In the link that Travis shared you can see that the UART is exposed on J9 of the M0090 add-on board: "M0090 - 5G Add-On Board J9 Pins 2/3 (Tx/Rx)"

                    V 1 Reply Last reply
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                    • tomT tom

                      @valvarez In the link that Travis shared you can see that the UART is exposed on J9 of the M0090 add-on board: "M0090 - 5G Add-On Board J9 Pins 2/3 (Tx/Rx)"

                      V Offline
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                      valvarez
                      Contributor
                      wrote on last edited by
                      #19

                      @tom @modaltb I had not understood the nomenclature, but with what you have told me I understood it. Thank you so much!!!

                      1 Reply Last reply
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                      • modaltbM modaltb

                        @valvarez

                        A bit hidden but it's /dev/ttyHS2

                        https://docs.modalai.com/voxl2-linux-user-guide/#devttyhs2---hsb2b-connector-uart

                        We ship a little helper tool that you can do a loop back test real quick if you make a cable that shorts pins 2/3:

                        qrb5165io-uart-test -d /dev/ttyHS2
                        
                        V Offline
                        V Offline
                        valvarez
                        Contributor
                        wrote on last edited by
                        #20

                        @modaltb
                        Hello.
                        I have tried this command following what you mentioned and it doesn't work.
                        Is there anything special I have to try?
                        Is it possible to connect the IO Board to the UART /dev/ttyHS2 taking this into account in the firmware update bash script?
                        WhatsApp Image 2025-02-14 at 18.46.24.jpeg WhatsApp Image 2025-02-14 at 18.46.26.jpeg
                        03b6bbbf-7d37-4977-a3ce-712c6ecc54a3-image.png

                        Alex KushleyevA 1 Reply Last reply
                        0
                        • V valvarez

                          @modaltb
                          Hello.
                          I have tried this command following what you mentioned and it doesn't work.
                          Is there anything special I have to try?
                          Is it possible to connect the IO Board to the UART /dev/ttyHS2 taking this into account in the firmware update bash script?
                          WhatsApp Image 2025-02-14 at 18.46.24.jpeg WhatsApp Image 2025-02-14 at 18.46.26.jpeg
                          03b6bbbf-7d37-4977-a3ce-712c6ecc54a3-image.png

                          Alex KushleyevA Offline
                          Alex KushleyevA Offline
                          Alex Kushleyev
                          ModalAI Team
                          wrote on last edited by
                          #21

                          @valvarez , the usage for the test tool is as follows:

                          voxl2:/$ qrb5165io-uart-test -h
                          Description: runs hardware loopback test on specified bus
                          
                          Usage: qrb5165io-uart-test
                          
                              -d <device ID> (eg 3 for /dev/ttyHS3)
                          

                          So you should run your test as:

                          voxl2:/$ qrb5165io-uart-test -d 2
                          [INFO]: success!
                          
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