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  3. Warning PX4 disconnected from UART

Warning PX4 disconnected from UART

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  • modaltbM Offline
    modaltbM Offline
    modaltb
    ModalAI Team
    wrote on last edited by
    #2

    Hi @mohammednaveed ,

    Sorry for the lag, is this still showing up as an issue?

    One way I try to trouble shoot the MAVLink connection over the UART from the VOXL processor(s) to Flight Core STM32 is using: https://docs.modalai.com/voxl-vision-px4-nuttx-shell/#interactive-mode

    From the other side, if you can open a MAVLink connection over USB to the Flight Core, and run mavlink status from the nutshell, to see if you have any active traffic?

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    • M Offline
      M Offline
      mohammednaveed
      wrote on last edited by
      #3

      Hi @modaltb
      Its alright!
      It still shows up randomly, will try your suggested method and get back soon!

      Thanks & Regards,
      Mohammed Naveed

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      • M Offline
        M Offline
        mohammednaveed
        wrote on last edited by mohammednaveed
        #4

        Hi @modaltb
        I checked it today, the issue still exists!
        I followed your instructions and have attached the following messages. This is only happening on this Voxl flight deck unit, my other unit is working perfectly.

        Voxl FD unit 2.png

        loading our own config file
        =================================================================
        Parameters as loaded from config file:
        qgc_ip:                     192.168.1.114
        en_localhost_mavlink_udp    1
        en_secondary_qgc:           0
        secondary_qgc_ip:           192.168.1.214
        qgc_udp_port_number:        14550
        localhost_udp_port_number:  14551
        udp_mtu:                    512
        en_vio:                     1
        en_voa:                     1
        en_send_vio_to_qgc:         1
        en_send_voa_to_qgc:         1
        en_set_clock_from_gps:      1
        en_force_onboard_mav1_mode: 1
        en_reset_px4_on_error:      1
        qvio_auto_reset_quality:    0.000500
        en_adsb:                    0
        adsb_uart_bus:              7
        adsb_uart_baudrate:         57600
        px4_uart_bus:               5
        px4_uart_baudrate:          921600
        offboard_mode:              off
        follow_tag_id:              0
        en_tag_fixed_frame:         0
        fixed_frame_filter_len:     5
        en_transform_mavlink_pos_setpoints_from_fixed_frame:0
        =================================================================
        loading extrinsics config file
        starting geometry module
        starting px4 monitor
        starting uart mavlink
        Successfully opened mavparser
        uart send msgid:   0 sysid:  0 compid:197
        starting udp mavlink
        Adding manual QGC IP address to udp connection list: 192.168.1.114
        Added new UDP connection to 192.168.1.114
        starting px4 shell
        starting fixed pose input
        starting vio manager
        starting tag manager
        starting voa manager
        Init complete, entering main loop
        Connected to voxl-qvio-server
        done updating transforms to use imu: imu0
        uart send msgid:   0 sysid:255 compid:190
        uart send msgid:   0 sysid:255 compid:190
        WARNING PX4 DISCONNECTED FROM UART
        uart send msgid:   0 sysid:255 compid:190
        uart send msgid:   0 sysid:255 compid:190
        ^C
        received SIGINT Ctrl-C
        Starting shutdown sequence
        Stopping adsb
        stopping voa manager
        stopping tag manager
        stopping vio manager
        stopping fixed pose in module
        stopping px4 shell module
        Stopping udp mavlink module
        exiting QGC udp listener thread
        exiting localhost udp listener thread
        udp_mavlink stopped
        Stopping uart mavlink module
        waiting for uart reader thread to join
        waiting for SDSP mavparser to close
        Stopping px4 monitor
        closing remaining client pipes
        closing remaining server pipes
        Removing PID file
        exiting
        
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        • M Offline
          M Offline
          mohammednaveed
          wrote on last edited by
          #5

          Is there a possibility that my VOXL board is bricked? Since the issue hasn't been resolved.

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          • modaltbM Offline
            modaltbM Offline
            modaltb
            ModalAI Team
            wrote on last edited by
            #6

            Hi @mohammednaveed ,

            The screen shot from QGC is of the unit with the issue? I'm a little confused as it shows a connection here which is that connecting to the VOXL:
            81cc0fab-fb77-4ee9-9971-2e9c16dff534-image.png

            If you can adb into the VOXL side and also get a MAVLink connection over USB to the Flight Core side, I'd say no it's not bricked.

            I'm wondering if we are missing something else. Are you modifying the PX4 FW or software on VOXL at all?

            What else are you running if anything on VOXL?

            There's a physical UART connecting the two, there are discrete components on the board such as ESD diodes, is the hardware being altered or installed into anything or just used in a Flight Deck? It's sounding like software and maybe an edge case with timing if it's intermittent though... if hardware issue it wouldn't work at all..

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            • M Offline
              M Offline
              mohammednaveed
              wrote on last edited by
              #7

              Hi @modaltb
              No I can ADB into the voxl, so its not bricked!
              This board is brand new and we were just configuring the flight core and we had just updated the custom firmware from v0.0.5 to v0.2.3.
              We just wanted to do VOA.
              However we found the issue, it seems to be a hardware issue!
              The J12 port to which the TELEM cable is connected to is not working correctly. I physically inspected if there are any damages but couldnt find anything wrong.
              This voxl was not able to communicate with another flight core as well. But once we shifted to J10 port it started to work correctly.
              So is it still hardware issue?

              Thanks & Regards,
              Mohammed Naveed

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              • modaltbM Offline
                modaltbM Offline
                modaltb
                ModalAI Team
                wrote on last edited by
                #8

                Hi @mohammednaveed ,

                AH ok I thought you had a VOXL-Flight, but it sounds like you have a VOXL and an external flight controller?

                J12 is on the VOXL:
                78be1d65-234a-4d8f-a75b-96183974115f-image.png

                On VOXL-Flight, it's internally routed.

                OK, we have a loop back test that you can use to test the hardware on J12.

                If you can connect pins 2/3 together via a custom cable, you can try the loop back test to see if the HW is OK: https://gitlab.com/voxl-public/core-libs/libvoxl_io/-/blob/master/lib/apps/voxl-uart-loopback.c#L54

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                • M Offline
                  M Offline
                  mohammednaveed
                  wrote on last edited by
                  #9

                  Hi @modaltb
                  Sorry if i didnt mention this earlier. Its a VOXL flight deck which is having this issue. My other VOXL flight deck is working fine and we tried to interchange the board and see where the issue was and found out to be the J12 port. In the other flight deck J12 is working correctly.
                  I'll try the loop back test.

                  Thanks & Regards,
                  Mohammed Naveed

                  D 1 Reply Last reply
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                  • M mohammednaveed

                    Hi @modaltb
                    Sorry if i didnt mention this earlier. Its a VOXL flight deck which is having this issue. My other VOXL flight deck is working fine and we tried to interchange the board and see where the issue was and found out to be the J12 port. In the other flight deck J12 is working correctly.
                    I'll try the loop back test.

                    Thanks & Regards,
                    Mohammed Naveed

                    D Offline
                    D Offline
                    DarkKnightCH
                    Contributor
                    wrote on last edited by
                    #10

                    @mohammednaveed Hi, have you solved your issue? Do you know where the issue is from?

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                    • modaltbM modaltb

                      Hi @mohammednaveed ,

                      AH ok I thought you had a VOXL-Flight, but it sounds like you have a VOXL and an external flight controller?

                      J12 is on the VOXL:
                      78be1d65-234a-4d8f-a75b-96183974115f-image.png

                      On VOXL-Flight, it's internally routed.

                      OK, we have a loop back test that you can use to test the hardware on J12.

                      If you can connect pins 2/3 together via a custom cable, you can try the loop back test to see if the HW is OK: https://gitlab.com/voxl-public/core-libs/libvoxl_io/-/blob/master/lib/apps/voxl-uart-loopback.c#L54

                      J Offline
                      J Offline
                      janikaoh
                      wrote on last edited by
                      #11

                      @modaltb Hi there! May I ask how the loopback test is conducted? How do you get the github file to run on VOXL? Thank you!

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