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  4. RC Transmitter Won't Bind

RC Transmitter Won't Bind

Scheduled Pinned Locked Moved VOXL 2
px4flight-deckvoxl2
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  • Eric KatzfeyE Eric Katzfey

    @camharrisvayu Oh, interesting. Can you share a log of that behavior?

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    camharrisvayu
    Contributor
    wrote on last edited by
    #9

    @Eric-Katzfey Interestingly (and unfortunately), I can't seem to recreate this behavior with anything I try. Any other ideas?

    Eric KatzfeyE 1 Reply Last reply
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    • C camharrisvayu

      @Eric-Katzfey Interestingly (and unfortunately), I can't seem to recreate this behavior with anything I try. Any other ideas?

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

      @camharrisvayu The log showed that the RC input and IMU input as coming in correctly. But EKF2 is not commanding the motors to do anything. So it could be a parameter setting issue. But I don't see anything obviously wrong. I can ask some colleagues to look at the log to see if they see anything wrong.

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      • Eric KatzfeyE Eric Katzfey

        @camharrisvayu The log showed that the RC input and IMU input as coming in correctly. But EKF2 is not commanding the motors to do anything. So it could be a parameter setting issue. But I don't see anything obviously wrong. I can ask some colleagues to look at the log to see if they see anything wrong.

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        camharrisvayu
        Contributor
        wrote on last edited by
        #11

        @Eric-Katzfey Great thanks! Do you know how I'd need to adjust settings in 0.9.5 to get the CRSF receiver/transmitter to communicate correctly? Since that version is responding to virtual joysticks, I'm wondering if I could get the transmitter bound if I could at least start flying that SDK version for now.

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        • C camharrisvayu

          @Eric-Katzfey Great thanks! Do you know how I'd need to adjust settings in 0.9.5 to get the CRSF receiver/transmitter to communicate correctly? Since that version is responding to virtual joysticks, I'm wondering if I could get the transmitter bound if I could at least start flying that SDK version for now.

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

          @camharrisvayu You can try setting the baudrate to 420000 in the file /etc/modalai/voxl-px4.config where it starts the CRSF RAW driver and currently specifies a 250000 baudrate.

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          • Eric KatzfeyE Eric Katzfey

            @camharrisvayu You can try setting the baudrate to 420000 in the file /etc/modalai/voxl-px4.config where it starts the CRSF RAW driver and currently specifies a 250000 baudrate.

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            camharrisvayu
            Contributor
            wrote on last edited by
            #13

            @Eric-Katzfey That still didn't want to work -- I tried setting CRSF_RAW and CRSF_MAV, both with default baud and 420k baud in the config file + changing the transmitter settings. Is there something I'm missing to get px4 to reboot using the new config file? I just ran voxl-configure-vision-px4 and selected 'no' for reset config file to factory defaults.

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            • C camharrisvayu

              @Eric-Katzfey That still didn't want to work -- I tried setting CRSF_RAW and CRSF_MAV, both with default baud and 420k baud in the config file + changing the transmitter settings. Is there something I'm missing to get px4 to reboot using the new config file? I just ran voxl-configure-vision-px4 and selected 'no' for reset config file to factory defaults.

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              Eric KatzfeyE Offline
              Eric Katzfey
              ModalAI Team
              wrote on last edited by
              #14

              @camharrisvayu Unfortunately, I think we only had support for raw CRSF using TBS Crossfire receivers using the 250000 baudrate. Standard ELRS receivers use 420k and our system image didn't support that back then. If you can get the receiver to use the 250000 baud rate then it may work.

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              • Eric KatzfeyE Eric Katzfey

                @camharrisvayu Unfortunately, I think we only had support for raw CRSF using TBS Crossfire receivers using the 250000 baudrate. Standard ELRS receivers use 420k and our system image didn't support that back then. If you can get the receiver to use the 250000 baud rate then it may work.

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                A Former User
                wrote on last edited by
                #15

                Yeah, that sounds like the issue. If the Rx has an LED, you can see if it is bound to the Tx, but not sending data to the flight controller due to incorrect baud rate.

                You can update the ELRS baud rate using the webUI: https://www.expresslrs.org/quick-start/webui/

                If you turn off the Tx, then turn on the Rx placing it close to your computer, in about a minute or so, the LED should flash quickly and the Wifi will come up.

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                • ? A Former User

                  Yeah, that sounds like the issue. If the Rx has an LED, you can see if it is bound to the Tx, but not sending data to the flight controller due to incorrect baud rate.

                  You can update the ELRS baud rate using the webUI: https://www.expresslrs.org/quick-start/webui/

                  If you turn off the Tx, then turn on the Rx placing it close to your computer, in about a minute or so, the LED should flash quickly and the Wifi will come up.

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                  camharrisvayu
                  Contributor
                  wrote on last edited by
                  #16

                  @RichieRich Thank you for all the input here -- unfortunately I don't have an ELRS receiver, but the crsf nano. Do you recommend buying the ELRS receiver due to the baud rate adjustability? It seems the crsf nano rx is set at 420k without a way to change it.

                  Thanks again!

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                  • C camharrisvayu

                    @RichieRich Thank you for all the input here -- unfortunately I don't have an ELRS receiver, but the crsf nano. Do you recommend buying the ELRS receiver due to the baud rate adjustability? It seems the crsf nano rx is set at 420k without a way to change it.

                    Thanks again!

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                    camharrisvayu
                    Contributor
                    wrote on last edited by
                    #17

                    @camharrisvayu Wait, scratch that. I got ahold of an ELRS rp3 receiver, and it's connected but the RSSI signal goes in and out, and causes sporadic values for all of the channels (sliders going crazy, going in and out of arming/mode/etc). Could this be due to more baud rate mismatch or have you seen this behavior before?

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                    • C camharrisvayu

                      @camharrisvayu Wait, scratch that. I got ahold of an ELRS rp3 receiver, and it's connected but the RSSI signal goes in and out, and causes sporadic values for all of the channels (sliders going crazy, going in and out of arming/mode/etc). Could this be due to more baud rate mismatch or have you seen this behavior before?

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                      camharrisvayu
                      Contributor
                      wrote on last edited by
                      #18

                      @camharrisvayu Ok, we should be able to close this issue -- I flashed 1.0.0 and uploaded params for the sentinel model and that made it so the RC inputs could control the drone -- not sure which parameter made the difference, but I may investigate and report back if I find out.

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