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  4. VOXL B2B Port connections questions

VOXL B2B Port connections questions

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  • A Offline
    A Offline
    amitga
    Contributor
    wrote on last edited by
    #1

    Hi.
    I was reading this:
    https://docs.modalai.com/voxl-datasheets-connectors/#j13-expansion-b2b-connection
    and wanted to make sure I understood corrrectly:
    There are 2 I2C ports/buses available on this connector (J13 - B2B) ?
    If so, can one be used as an I2C master/host, and the other as a slave (for use with external master) ?

    Also, I haven't seen any information about PWM outputs. Does the VOXL have any hardware PWM outputs? If so, on which pins?

    Thanks.

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    1
    • Chad SweetC Offline
      Chad SweetC Offline
      Chad Sweet
      ModalAI Team
      wrote on last edited by
      #2

      Yes, but to use the B2B connector you will need a custom PCB.

      There are other i2c available.

      There are no HW PWM on VOXL, but on VOXL Flight there are HW PWM through the Flight Core portion

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      • A Offline
        A Offline
        amitga
        Contributor
        wrote on last edited by amitga
        #3

        Thanks for your reply.
        Yeah, I was planning on breaking out the B2B connector to a PCB for dev purposes.

        So I shouldn't have any problems using the two I2C ports (on as master and other as slave) on the B2B, correct?

        Also, if I want to do SW based PWM, is there any GPIO pin on the B2B that you would recommend using, or can I choose any free GPIO pin ?

        Eric KatzfeyE 1 Reply Last reply
        0
        • A amitga

          Thanks for your reply.
          Yeah, I was planning on breaking out the B2B connector to a PCB for dev purposes.

          So I shouldn't have any problems using the two I2C ports (on as master and other as slave) on the B2B, correct?

          Also, if I want to do SW based PWM, is there any GPIO pin on the B2B that you would recommend using, or can I choose any free GPIO pin ?

          Eric KatzfeyE Offline
          Eric KatzfeyE Offline
          Eric Katzfey
          ModalAI Team
          wrote on last edited by
          #4

          @amitga The i2c ports on Voxl only support host mode, not slave mode. Also, we have never tested any i2c ports coming over the B2B connector and cannot say for sure whether they are even enabled in the system image.

          A 1 Reply Last reply
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          • Eric KatzfeyE Eric Katzfey

            @amitga The i2c ports on Voxl only support host mode, not slave mode. Also, we have never tested any i2c ports coming over the B2B connector and cannot say for sure whether they are even enabled in the system image.

            A Offline
            A Offline
            amitga
            Contributor
            wrote on last edited by
            #5

            @Eric-Katzfey Thanks for the reply.
            Is this a hardware limitation (i2c ports being host only) ?
            Are there any plans to enable i2c in slave mode on the VOXL ?

            Eric KatzfeyE 1 Reply Last reply
            0
            • A amitga

              @Eric-Katzfey Thanks for the reply.
              Is this a hardware limitation (i2c ports being host only) ?
              Are there any plans to enable i2c in slave mode on the VOXL ?

              Eric KatzfeyE Offline
              Eric KatzfeyE Offline
              Eric Katzfey
              ModalAI Team
              wrote on last edited by
              #6

              @amitga Yes, it is a hardware limitation.

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              • A Offline
                A Offline
                amitga
                Contributor
                wrote on last edited by
                #7

                OK.
                So what about SPI or UART on the B2B connector?
                Are they available and supported in OS/SW? If so, what modes does the SPI support (master/slave) ?
                What baudrate does the UART support?

                Thanks.

                Eric KatzfeyE 1 Reply Last reply
                0
                • A amitga

                  OK.
                  So what about SPI or UART on the B2B connector?
                  Are they available and supported in OS/SW? If so, what modes does the SPI support (master/slave) ?
                  What baudrate does the UART support?

                  Thanks.

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

                  @amitga The only thing we use over the B2B on our add-on boards is USB 2.0 and some GPIO. If you give us some idea of what you are trying to accomplish we may be able to offer some suggestions.

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