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  4. PX4 disconnected from UART & QGC cannot connected to modalAI

PX4 disconnected from UART & QGC cannot connected to modalAI

Scheduled Pinned Locked Moved VOXL m500 Reference Drone
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  • D DarkKnightCH

    HI,

    I also found this post which has the same issue with me. I tried to follow the suggestion in this post:I open a MAVLink connection over USB to the flight core, and run mavlink status from the nutshell

    
    NuttShell (NSH)
    nsh> mavlink status
    
    instance #0:
        GCS heartbeat:    267144 us ago
        mavlink chan: #0
        type:        USB CDC
        flow control: OFF
        rates:
          tx: 15.682 kB/s
          txerr: 0.000 kB/s
          tx rate mult: 1.000
          tx rate max: 800000 B/s
          rx: 0.046 kB/s
        FTP enabled: YES, TX enabled: YES
        mode: Config
        MAVLink version: 2
        transport protocol: serial (/dev/ttyACM0 @2000000)
        ping statistics:
          last: 1.72 ms
          mean: 2.18 ms
          max: 6541.72 ms
          min: 0.19 ms
          dropped packets: 5
    
    instance #1:
        mavlink chan: #1
        type:        GENERIC LINK OR RADIO
        flow control: ON
        rates:
          tx: 1.564 kB/s
          txerr: 0.000 kB/s
          tx rate mult: 1.000
          tx rate max: 2880 B/s
          rx: 0.000 kB/s
        FTP enabled: YES, TX enabled: YES
        mode: Normal
        MAVLink version: 1
        transport protocol: serial (/dev/ttyS6 @57600)
    
    instance #2:
        mavlink chan: #2
        type:        GENERIC LINK OR RADIO
        flow control: OFF
        rates:
          tx: 14.672 kB/s
          txerr: 0.000 kB/s
          tx rate mult: 1.000
          tx rate max: 46080 B/s
          rx: 0.000 kB/s
        FTP enabled: YES, TX enabled: YES
        mode: Onboard
        MAVLink version: 2
        transport protocol: serial (/dev/ttyS4 @921600)
    
    instance #3:
        mavlink chan: #3
        type:        GENERIC LINK OR RADIO
        flow control: ON
        rates:
          tx: 1.564 kB/s
          txerr: 0.000 kB/s
          tx rate mult: 1.000
          tx rate max: 2880 B/s
          rx: 0.000 kB/s
        FTP enabled: YES, TX enabled: YES
        mode: Normal
        MAVLink version: 1
        transport protocol: serial (/dev/ttyS1 @57600)
    

    From above information, I cannot track where the issue is, any suggestion?

    D Offline
    D Offline
    DarkKnightCH
    Contributor
    wrote on last edited by
    #5
    This post is deleted!
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    • D Offline
      D Offline
      DarkKnightCH
      Contributor
      wrote on last edited by DarkKnightCH
      #6

      More tests have done:
      (1) First, I can ssh into voxl through my laptop. And this means the wifi in VOXL is working.
      (2) I can adb into voxl board, which means that my voxl board is not bricked?
      (3)I can connect my flight core with my QGC via USB.
      (4)I tried to run voxl-inspect-services, and it shows
      Screenshot_2022-07-10_16-27-48.png
      (5)I also tried to run voxl-inspect-qvio, and it shows that
      Screenshot_2022-07-10_16-04-32.png

      (6)I also tried to reset the voxl-vision-px4 by running voxl-configure-vision-px4 as follows
      Screenshot_2022-07-10_16-33-19.png

      But there still is a WARNING show PX4 disconnected from UART.

      Any suggestion😧 ?

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      • Chad SweetC Offline
        Chad SweetC Offline
        Chad Sweet
        ModalAI Team
        wrote on last edited by
        #7

        That warning implies there is an issue in the comms between the Snapdragon and the STM32F7. Maybe try to reload the STM32F7 (Flight Core) firmware and see if that helps?

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        • D Offline
          D Offline
          DarkKnightCH
          Contributor
          wrote on last edited by DarkKnightCH
          #8

          @Chad-Sweet Yeah. I already reload a flight core firmware and it doesn't help. Is it possible that voxl-vision-px4 server is broken? The UART wire physical connection looks pretty valid. it is hard for me to find out where the issue is from.

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          • D Offline
            D Offline
            DarkKnightCH
            Contributor
            wrote on last edited by
            #9

            @Chad-Sweet I would like to update my voxl-suite-ipk meta package since I doubt maybe something is wrong about the voxl-vision-px4? is there a simple way to do it except flashing a new system image of voxl? should I use the following command to do it?

            opkg update && opkg upgrade
            
            1 Reply Last reply
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            • Chad SweetC Offline
              Chad SweetC Offline
              Chad Sweet
              ModalAI Team
              wrote on last edited by
              #10

              That warning implies a hardware issue more than a software issue. What if you try the nuttx shell to test connectivity between the Snapdragon and Flight Core?

              D 1 Reply Last reply
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              • Chad SweetC Chad Sweet

                That warning implies a hardware issue more than a software issue. What if you try the nuttx shell to test connectivity between the Snapdragon and Flight Core?

                D Offline
                D Offline
                DarkKnightCH
                Contributor
                wrote on last edited by
                #11

                @Chad-Sweet I tried to follow your advice and it shows

                voxl:~$ voxl-px4-shell
                ERROR opening /run/mpa/vvpx4_shell/
                most likely the voxl-vision-px4 service is not running
                

                I also tried to run

                systemctl restart voxl-vision-px4
                

                and

                voxl-vision-px4 status
                

                and it shows

                voxl:~$ voxl-vision-px4 status
                loading our own config file
                =================================================================
                Parameters as loaded from config file:
                qgc_ip:                     192.168.0.121
                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:         0
                en_send_voa_to_qgc:         0
                en_set_clock_from_gps:      1
                en_force_onboard_mav1_mode: 1
                en_reset_px4_on_error:      1
                qvio_auto_reset_quality:    0.000500
                horizon_cal_tolerance:      0.300000
                voa_upper_bound_m:          1.250000
                voa_lower_bound_m:          1.250000
                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
                starting udp mavlink
                Adding manual QGC IP address to udp connection list: 192.168.0.121
                Added new UDP connection to 192.168.0.121
                starting px4 shell
                starting fixed pose input
                starting vio manager
                starting tag manager
                starting voa manager
                starting control input pipe
                Init complete, entering main loop
                Connected to voxl-qvio-server
                updating to use imu: imu0
                done updating transforms to use imu: imu0
                Connected to voxl-tag-detector
                Connected to voxl-dfs-server
                WARNING PX4 DISCONNECTED FROM UART
                

                any suggestion?

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                • Chad SweetC Offline
                  Chad SweetC Offline
                  Chad Sweet
                  ModalAI Team
                  wrote on last edited by
                  #12

                  You could try a fresh install by following the instructions here: https://docs.modalai.com/voxl-suite/ . There does seem to be a chance your hardware is damaged though.

                  D 1 Reply Last reply
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                  • Chad SweetC Chad Sweet

                    You could try a fresh install by following the instructions here: https://docs.modalai.com/voxl-suite/ . There does seem to be a chance your hardware is damaged though.

                    D Offline
                    D Offline
                    DarkKnightCH
                    Contributor
                    wrote on last edited by
                    #13

                    @Chad-Sweet Yeah. I tried the following command

                    voxl-configure-opkg
                    

                    and

                    opkg update
                    

                    and then try to restart the voxl-vision-px4 and it seems nothing helps.

                    Since I can connect to voxl through wifi and adb, I have no idea why voxl will broken since I treat it very carefully. Indeed sometimes this QGC disconnection issue happens randomly. Could I mail back the Flight Core and VOXL to you and would you mind helping me check what is the issue?

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                    • A Offline
                      A Offline
                      Anubhav
                      Regular
                      wrote on last edited by
                      #14

                      @DarkKnightCH
                      Hi,
                      Are you able to connect to QGC now. if yes, what was the issue and how you rectified it?
                      Thanks!

                      T 1 Reply Last reply
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                      • A Anubhav

                        @DarkKnightCH
                        Hi,
                        Are you able to connect to QGC now. if yes, what was the issue and how you rectified it?
                        Thanks!

                        T Offline
                        T Offline
                        tpavlic
                        Contributor
                        wrote on last edited by
                        #15

                        @Anubhav and @DarkKnightCH: Was there any movement on this?

                        We have 7 drones with FCv2 (all of our other m500 drones have different FC's) that were also sent to us with the wrong radios. We were able to reconfigure the PX4 for the desired radios (and confirm RC connection to QGC), but running voxl-mavlink-server manually shows a UART error on the console. We are RMA'ing the 7 units with the bad mavlink back to ModalAI for a fix, but it would be great to save the shipping if a fix was found here.

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