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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 Offline
    D Offline
    DarkKnightCH
    Contributor
    wrote on last edited by
    #3

    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 1 Reply Last reply
    0
    • H howard

      @DarkKnightCH
      Hi, Please try restarting the voxl-vision-px4 by running systemctl restart voxl-vision-px4.
      Try enabling voxl-mavlink-server
      Also ensure you have right qgc ip address in /etc/modalai/voxl-vision-px4.

      D Offline
      D Offline
      DarkKnightCH
      Contributor
      wrote on last edited by
      #4

      @keil
      Hi, keil, Thanks for help.
      I tried to run the systemctl restart voxl-vision-px4, but it doesn't help.

      What do you mean enabling voxl-mavlink-server?

      QGC ip address is correct.

      1 Reply Last reply
      0
      • 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!
        1 Reply Last reply
        0
        • 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😧 ?

          1 Reply Last reply
          0
          • 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?

            1 Reply Last reply
            0
            • 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.

              1 Reply Last reply
              0
              • 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
                0
                • 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
                  0
                  • 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?

                    1 Reply Last reply
                    0
                    • 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
                      0
                      • 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?

                        1 Reply Last reply
                        0
                        • 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
                          0
                          • 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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