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PWM Servo IO Board

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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
    #7

    @Eric-Katzfey Thank you very much for the response. The kit I have purchased is the most complete one here: https://www.modalai.com/products/voxl2-io?variant=40905411035187
    Would what you mention be possible with this hardware?

    Eric KatzfeyE 1 Reply Last reply
    0
    • V valvarez

      @Eric-Katzfey Thank you very much for the response. The kit I have purchased is the most complete one here: https://www.modalai.com/products/voxl2-io?variant=40905411035187
      Would what you mention be possible with this hardware?

      Eric KatzfeyE Offline
      Eric KatzfeyE Offline
      Eric Katzfey
      ModalAI Team
      wrote on last edited by
      #8

      @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.

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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
        V Offline
        valvarez
        Contributor
        wrote on last edited by
        #9

        @Eric-Katzfey First of all, thank you for your patience.
        My intention is to be able to connect a servo that allows a load to be released during the flight based on a signal sent by the VOXL itself (we will be connected to the drone through MAVLINK)
        Seeing that there was no possibility of connecting a servo to the VOXL, I purchased the IO Board, to which I would connect the servo.
        The thing is that when I see the connection diagram of the IO Board, I see that it is connected to a connector already used in the VOXL.
        Is there any option that the device that is connected to the IO Board location can be connected to the IO Board, maintaining the option of using the RC that is supplied with the Sentinel and having the extra of being able to connect a deployment servo?

        Or failing that, if I wanted to send a signal through Mavlink to be able to release a load through a servo, what would the operation be like?

        Thank you so much

        1 Reply Last reply
        0
        • 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
          V Offline
          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
          0
          • 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
              0
              • 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
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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
                    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!!!

                            1 Reply 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
                              #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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