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  3. UART communication using J19 - VOXL2 SENTINEL

UART communication using J19 - VOXL2 SENTINEL

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  • leonardo Andrade 0L Offline
    leonardo Andrade 0L Offline
    leonardo Andrade 0
    Contributor
    wrote on last edited by
    #1

    hi guys!

    I have a very dumb question.

    I'd like to develop a gimbal using uart communication. But since I'd already removed the GPS module, I thought I'd use these uart ports.

    I tried connecting an ESP32 to J19 of the VOXL2 (PINOS: #2-TX, #3-RX, #6-GND) and checking communication using the qrb5165io-uart-test and qrb5165io-slpi-uart-test commands.

    I also checked this link:

    https://docs.modalai.com/voxl2-qups/

    Could you please guide me?!
    Thank you!

    Alex KushleyevA 1 Reply Last reply
    0
    • leonardo Andrade 0L leonardo Andrade 0

      hi guys!

      I have a very dumb question.

      I'd like to develop a gimbal using uart communication. But since I'd already removed the GPS module, I thought I'd use these uart ports.

      I tried connecting an ESP32 to J19 of the VOXL2 (PINOS: #2-TX, #3-RX, #6-GND) and checking communication using the qrb5165io-uart-test and qrb5165io-slpi-uart-test commands.

      I also checked this link:

      https://docs.modalai.com/voxl2-qups/

      Could you please guide me?!
      Thank you!

      Alex KushleyevA Offline
      Alex KushleyevA Offline
      Alex Kushleyev
      ModalAI Team
      wrote on last edited by
      #2

      @leonardo-Andrade-0 , the UART port on J19 is connected to the DSP where PX4 typically runs. This means the uart test apps from the cpu side (which interface with DSP to get to the UART port) cannot run concurrently with PX4 (currently only one app can run on DSP at a time).

      Perhaps when you were testing, PX4 was running and your test did not work?

      Would you want to interface to your gimbal from PX4 running on DSP or from CPU?

      Alex

      leonardo Andrade 0L C 2 Replies Last reply
      0
      • Alex KushleyevA Alex Kushleyev

        @leonardo-Andrade-0 , the UART port on J19 is connected to the DSP where PX4 typically runs. This means the uart test apps from the cpu side (which interface with DSP to get to the UART port) cannot run concurrently with PX4 (currently only one app can run on DSP at a time).

        Perhaps when you were testing, PX4 was running and your test did not work?

        Would you want to interface to your gimbal from PX4 running on DSP or from CPU?

        Alex

        leonardo Andrade 0L Offline
        leonardo Andrade 0L Offline
        leonardo Andrade 0
        Contributor
        wrote on last edited by
        #3

        @Alex-Kushleyev

        Hi Alex,

        When I tested was with the px4 running.

        That apps you said is like this?
        https://docs.px4.io/main/en/modules/hello_sky.html

        I’m still learning some parts of px4 itself 😅.

        Ideally, I thought to connect the esp to cpu where I could to read the data coming , such as to connect a arduino board in a computer. However to control the gimbal should be using mavlink .

        It’s like to learn to use the peripherals of my sentinel, because in the future I need also to connect UART lidar.

        What do you recommend? Because the others UARTs ports that I have are full right now.

        Best regards!

        1 Reply Last reply
        0
        • Alex KushleyevA Alex Kushleyev

          @leonardo-Andrade-0 , the UART port on J19 is connected to the DSP where PX4 typically runs. This means the uart test apps from the cpu side (which interface with DSP to get to the UART port) cannot run concurrently with PX4 (currently only one app can run on DSP at a time).

          Perhaps when you were testing, PX4 was running and your test did not work?

          Would you want to interface to your gimbal from PX4 running on DSP or from CPU?

          Alex

          C Offline
          C Offline
          constantines
          Contributor
          wrote on last edited by
          #4

          @Alex-Kushleyev
          Hi, and what if I want to add a Mavlink sensor (say a number of distance sensors connected to a dedicated MCU) to the VOXL2 using the J19 (PINS: #2-TX, #3-RX, #6-GND) instead of the GPS? I plan to read it using PX4. It that possible?

          Eric KatzfeyE 1 Reply Last reply
          0
          • C constantines

            @Alex-Kushleyev
            Hi, and what if I want to add a Mavlink sensor (say a number of distance sensors connected to a dedicated MCU) to the VOXL2 using the J19 (PINS: #2-TX, #3-RX, #6-GND) instead of the GPS? I plan to read it using PX4. It that possible?

            Eric KatzfeyE Offline
            Eric KatzfeyE Offline
            Eric Katzfey
            ModalAI Team
            wrote on last edited by
            #5

            @constantines Unfortunately, the PX4 Mavlink module is only running on the applications processor (Linux) and not on the DSP side. Mavlink would have to be added to the DSP PX4 build.

            1 Reply Last reply
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