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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
    #1

    Hi,
    As you can see from the first figure, when I run:voxl_vision_px4 status, it shows that WARNING PX4 DISCONNECTED FROM UART, do you know how to address this issue? The firmware version is 1.11.3.
    7c8bbe5d-58bb-4dd7-9107-d2d18a2807c5.png

    I have noticed that this post have the same issue with mine. However, my ModalAI's MAV_1_MODE is already set to Onboard. https://forum.modalai.com/topic/70/warning-px4-disconnected-error-message-from-voxl-vision-px4?_=1657322074175

    Meanwhile, right now the QGC cannot connect to ModalAI.
    5f33bd94-aca5-4343-8ec5-f03c39e91654.png

    Any suggestion? Thanks in advance!

    H 1 Reply Last reply
    0
    • D DarkKnightCH

      Hi,
      As you can see from the first figure, when I run:voxl_vision_px4 status, it shows that WARNING PX4 DISCONNECTED FROM UART, do you know how to address this issue? The firmware version is 1.11.3.
      7c8bbe5d-58bb-4dd7-9107-d2d18a2807c5.png

      I have noticed that this post have the same issue with mine. However, my ModalAI's MAV_1_MODE is already set to Onboard. https://forum.modalai.com/topic/70/warning-px4-disconnected-error-message-from-voxl-vision-px4?_=1657322074175

      Meanwhile, right now the QGC cannot connect to ModalAI.
      5f33bd94-aca5-4343-8ec5-f03c39e91654.png

      Any suggestion? Thanks in advance!

      H Offline
      H Offline
      howard
      Regular
      wrote on last edited by
      #2

      @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 1 Reply Last reply
      0
      • 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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