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PWM Servo IO Board

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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

          V 1 Reply Last reply
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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
            V Offline
            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
            0
            • 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

              Link Preview Image
              VOXL 2 Linux User Guide

              ModalAI technical documentation for VOXL and VOXL 2 Companion Computers for PX4 and ArduPilot Obstacle Avoidance and GPS-denied navigation, assembled in the USA

              favicon

              ModalAI Technical Docs (docs.modalai.com)

              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 2 Replies Last reply
              0
              • modaltbM modaltb

                @valvarez

                A bit hidden but it's /dev/ttyHS2

                Link Preview Image
                VOXL 2 Linux User Guide

                ModalAI technical documentation for VOXL and VOXL 2 Companion Computers for PX4 and ArduPilot Obstacle Avoidance and GPS-denied navigation, assembled in the USA

                favicon

                ModalAI Technical Docs (docs.modalai.com)

                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
                #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
                0
                • 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
                  0
                  • 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
                    V Offline
                    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!!!

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                    • modaltbM modaltb

                      @valvarez

                      A bit hidden but it's /dev/ttyHS2

                      Link Preview Image
                      VOXL 2 Linux User Guide

                      ModalAI technical documentation for VOXL and VOXL 2 Companion Computers for PX4 and ArduPilot Obstacle Avoidance and GPS-denied navigation, assembled in the USA

                      favicon

                      ModalAI Technical Docs (docs.modalai.com)

                      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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