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lis3mdl magnetometer

Scheduled Pinned Locked Moved VOXL 2 Mini
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  • Eric KatzfeyE Eric Katzfey

    @mkriesel Can you use qmc5883l or ist8310 instead? Those two are already supported directly.

    M Offline
    M Offline
    mkriesel
    Regular
    wrote on last edited by
    #5

    @Eric-Katzfey Hello again, question on accessing things plugged into the j19 i2c port, how would I access them outside of px4? I saw this https://forum.modalai.com/post/13604 so I'm guessing I can't use /dev/i2c-0 to acccess that port, however looking through the px4 for referenec it seems like it does use the app proc https://github.com/modalai/px4-firmware/blob/7fbbdc31e8a61525777d8edcf8f339a738abf138/src/lib/drivers/device/posix/I2C.cpp#L87 So is this the correct way to do it or is there something else I have to do?

    Eric KatzfeyE 1 Reply Last reply
    0
    • M mkriesel

      @Eric-Katzfey Hello again, question on accessing things plugged into the j19 i2c port, how would I access them outside of px4? I saw this https://forum.modalai.com/post/13604 so I'm guessing I can't use /dev/i2c-0 to acccess that port, however looking through the px4 for referenec it seems like it does use the app proc https://github.com/modalai/px4-firmware/blob/7fbbdc31e8a61525777d8edcf8f339a738abf138/src/lib/drivers/device/posix/I2C.cpp#L87 So is this the correct way to do it or is there something else I have to do?

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

      @mkriesel That is the i2c driver code for the "posix" px4 platform, or apps side. That won't help with J19 which is only available to the dsp. We don't currently provide a way to access those i2c outside of px4.

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      • Eric KatzfeyE Eric Katzfey

        @mkriesel That is the i2c driver code for the "posix" px4 platform, or apps side. That won't help with J19 which is only available to the dsp. We don't currently provide a way to access those i2c outside of px4.

        M Offline
        M Offline
        mkriesel
        Regular
        wrote on last edited by
        #7

        @Eric-Katzfey is it possible for you to provide me the code that interfaces with the j19 i2c in px4 so I can look at if I wanted to write my own interface with that port?

        Eric KatzfeyE 1 Reply Last reply
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        • M mkriesel

          @Eric-Katzfey is it possible for you to provide me the code that interfaces with the j19 i2c in px4 so I can look at if I wanted to write my own interface with that port?

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

          @mkriesel At a high level it is a driver like: https://github.com/PX4/PX4-Autopilot/tree/main/src/drivers/magnetometer/isentek/ist8310. This, on the Qurt platform, will end up using this low level driver: https://github.com/PX4/PX4-Autopilot/blob/main/src/lib/drivers/device/qurt/I2C.cpp

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          • Eric KatzfeyE Eric Katzfey

            @mkriesel At a high level it is a driver like: https://github.com/PX4/PX4-Autopilot/tree/main/src/drivers/magnetometer/isentek/ist8310. This, on the Qurt platform, will end up using this low level driver: https://github.com/PX4/PX4-Autopilot/blob/main/src/lib/drivers/device/qurt/I2C.cpp

            M Offline
            M Offline
            mkriesel
            Regular
            wrote on last edited by
            #9

            @Eric-Katzfey Hello
            I've looked through px4 and I'm alittle lost on how exactly this all works maybe you can give alittle more detail. I understand the the ports are configured to the spli proc to be used on the dsp but where extacly does this interface, In I2C.cpp you showed above it sets all the functions to null and then they get decalred on init but I can't find where they actually interface with the i2c registers.After that would I need to compile my program with Hexagon SDK or is it possible at all to interface with this i2c port in the normal Ubuntu environment at all?

            My understanding is that the uart on the same J19 is configured in the same way but I can access those through the libqrb5165-io and voxl-io.h so is there something similar available for i2c or could I implement my own in a similar way and if I could how would I go about doing this?

            Eric KatzfeyE 4 Replies Last reply
            0
            • M mkriesel

              @Eric-Katzfey Hello
              I've looked through px4 and I'm alittle lost on how exactly this all works maybe you can give alittle more detail. I understand the the ports are configured to the spli proc to be used on the dsp but where extacly does this interface, In I2C.cpp you showed above it sets all the functions to null and then they get decalred on init but I can't find where they actually interface with the i2c registers.After that would I need to compile my program with Hexagon SDK or is it possible at all to interface with this i2c port in the normal Ubuntu environment at all?

              My understanding is that the uart on the same J19 is configured in the same way but I can access those through the libqrb5165-io and voxl-io.h so is there something similar available for i2c or could I implement my own in a similar way and if I could how would I go about doing this?

              Eric KatzfeyE Offline
              Eric KatzfeyE Offline
              Eric Katzfey
              ModalAI Team
              wrote on last edited by
              #10

              @mkriesel The low level driver is Qualcomm proprietary so we cannot share it. But you don't need to look at that code to use an i2c port. You just need to use the interface functions provided by px4.

              1 Reply Last reply
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              • M mkriesel

                @Eric-Katzfey Hello
                I've looked through px4 and I'm alittle lost on how exactly this all works maybe you can give alittle more detail. I understand the the ports are configured to the spli proc to be used on the dsp but where extacly does this interface, In I2C.cpp you showed above it sets all the functions to null and then they get decalred on init but I can't find where they actually interface with the i2c registers.After that would I need to compile my program with Hexagon SDK or is it possible at all to interface with this i2c port in the normal Ubuntu environment at all?

                My understanding is that the uart on the same J19 is configured in the same way but I can access those through the libqrb5165-io and voxl-io.h so is there something similar available for i2c or could I implement my own in a similar way and if I could how would I go about doing this?

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

                @mkriesel Yes, you would need to compile the DSP code with the Hexagon SDK.

                1 Reply Last reply
                0
                • M mkriesel

                  @Eric-Katzfey Hello
                  I've looked through px4 and I'm alittle lost on how exactly this all works maybe you can give alittle more detail. I understand the the ports are configured to the spli proc to be used on the dsp but where extacly does this interface, In I2C.cpp you showed above it sets all the functions to null and then they get decalred on init but I can't find where they actually interface with the i2c registers.After that would I need to compile my program with Hexagon SDK or is it possible at all to interface with this i2c port in the normal Ubuntu environment at all?

                  My understanding is that the uart on the same J19 is configured in the same way but I can access those through the libqrb5165-io and voxl-io.h so is there something similar available for i2c or could I implement my own in a similar way and if I could how would I go about doing this?

                  Eric KatzfeyE Offline
                  Eric KatzfeyE Offline
                  Eric Katzfey
                  ModalAI Team
                  wrote on last edited by
                  #12

                  @mkriesel You cannot access the DSP i2c ports from the applications processor.

                  1 Reply Last reply
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                  • M mkriesel

                    @Eric-Katzfey Hello
                    I've looked through px4 and I'm alittle lost on how exactly this all works maybe you can give alittle more detail. I understand the the ports are configured to the spli proc to be used on the dsp but where extacly does this interface, In I2C.cpp you showed above it sets all the functions to null and then they get decalred on init but I can't find where they actually interface with the i2c registers.After that would I need to compile my program with Hexagon SDK or is it possible at all to interface with this i2c port in the normal Ubuntu environment at all?

                    My understanding is that the uart on the same J19 is configured in the same way but I can access those through the libqrb5165-io and voxl-io.h so is there something similar available for i2c or could I implement my own in a similar way and if I could how would I go about doing this?

                    Eric KatzfeyE Offline
                    Eric KatzfeyE Offline
                    Eric Katzfey
                    ModalAI Team
                    wrote on last edited by
                    #13

                    @mkriesel We don't have any immediate plans to add dsp i2c access to libqrb5165-io.

                    M 1 Reply Last reply
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                    • Eric KatzfeyE Eric Katzfey

                      @mkriesel We don't have any immediate plans to add dsp i2c access to libqrb5165-io.

                      M Offline
                      M Offline
                      mkriesel
                      Regular
                      wrote on last edited by
                      #14

                      @Eric-Katzfey Hi again, sorry for all the questions but for an update, I was able to get the compass working for my application by using the mavlink pipe and for now this is sufficient, however if I wanted to reconfigure the port to have it on the application processor instead could I do that? Again, it doesn't matter if I lose functionality in px4 because I don't plan to use it if I don't have to but if those GPIO pins are available I would like to explore that option.

                      Thanks for all the help so far.

                      Eric KatzfeyE 1 Reply Last reply
                      0
                      • M mkriesel

                        @Eric-Katzfey Hi again, sorry for all the questions but for an update, I was able to get the compass working for my application by using the mavlink pipe and for now this is sufficient, however if I wanted to reconfigure the port to have it on the application processor instead could I do that? Again, it doesn't matter if I lose functionality in px4 because I don't plan to use it if I don't have to but if those GPIO pins are available I would like to explore that option.

                        Thanks for all the help so far.

                        Eric KatzfeyE Offline
                        Eric KatzfeyE Offline
                        Eric Katzfey
                        ModalAI Team
                        wrote on last edited by
                        #15

                        @mkriesel The VOXL 2 does not have any i2c brought out to connectors for the applications processor. However, there are some add-on boards that do include this. For example: https://docs.modalai.com/usb2-type-a-breakout-add-on/

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                        • Eric KatzfeyE Eric Katzfey

                          @mkriesel The VOXL 2 does not have any i2c brought out to connectors for the applications processor. However, there are some add-on boards that do include this. For example: https://docs.modalai.com/usb2-type-a-breakout-add-on/

                          M Offline
                          M Offline
                          mkriesel
                          Regular
                          wrote on last edited by
                          #16

                          @Eric-Katzfey I undertand you do not have any Voxl 2 mini schematics open to the public but is it possible for you to share with me the gpio pins that J19 are on for the QRB5165 board?

                          Alex KushleyevA VinnyV 2 Replies Last reply
                          0
                          • M mkriesel

                            @Eric-Katzfey I undertand you do not have any Voxl 2 mini schematics open to the public but is it possible for you to share with me the gpio pins that J19 are on for the QRB5165 board?

                            Alex KushleyevA Online
                            Alex KushleyevA Online
                            Alex Kushleyev
                            ModalAI Team
                            wrote on last edited by
                            #17

                            @mkriesel ,

                            Link Preview Image
                            VOXL 2 Mini Connectors

                            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)

                            here is a link for voxl2 (not mini) : https://docs.modalai.com/voxl2-connectors/

                            does this help?

                            VinnyV 1 Reply Last reply
                            0
                            • Alex KushleyevA Alex Kushleyev

                              @mkriesel ,

                              Link Preview Image
                              VOXL 2 Mini Connectors

                              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)

                              here is a link for voxl2 (not mini) : https://docs.modalai.com/voxl2-connectors/

                              does this help?

                              VinnyV Offline
                              VinnyV Offline
                              Vinny
                              ModalAI Team
                              wrote on last edited by
                              #18

                              @Alex-Kushleyev @mkriesel , I just updated that table to include the raw GPIO numbers.
                              e79aa1fe-ff26-45a0-ad24-65d59af5004b-image.png
                              However, I'm certain that they are unusable as GPIOs due to Trust Zone settings we have applied using them as I2C/UART etc.

                              1 Reply Last reply
                              0
                              • M mkriesel

                                @Eric-Katzfey I undertand you do not have any Voxl 2 mini schematics open to the public but is it possible for you to share with me the gpio pins that J19 are on for the QRB5165 board?

                                VinnyV Offline
                                VinnyV Offline
                                Vinny
                                ModalAI Team
                                wrote on last edited by
                                #19

                                Hi @mkriesel
                                Have you seen this product we offer? This may be something that interests you:
                                https://docs.modalai.com/voxl2-dev-test-board/

                                Our purchase link is buried in our beta section due to the risk of such product:
                                https://www.modalai.com/pages/beta-voxl-2-b2b-breakout-board
                                It includes a lot of extras not posted such as a tray to hold everything together, an SD Card, many cables, and several jumpers to get you going.
                                Hope this helps!

                                M 1 Reply Last reply
                                0
                                • VinnyV Vinny

                                  Hi @mkriesel
                                  Have you seen this product we offer? This may be something that interests you:
                                  https://docs.modalai.com/voxl2-dev-test-board/

                                  Our purchase link is buried in our beta section due to the risk of such product:
                                  https://www.modalai.com/pages/beta-voxl-2-b2b-breakout-board
                                  It includes a lot of extras not posted such as a tray to hold everything together, an SD Card, many cables, and several jumpers to get you going.
                                  Hope this helps!

                                  M Offline
                                  M Offline
                                  mkriesel
                                  Regular
                                  wrote on last edited by
                                  #20

                                  @Vinny Thanks for the help on this I really appreciate it. I'll take a look.

                                  1 Reply Last reply
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