Cannot configure GNSS for ZED F9R on Ubuntu 20.04 ROS 2 Foxy ARM64

[alex-shearer-swe]

Describe the bug Repeated attempts to start ROS 2 Foxy ublox_gps node for ZED F9R device always end in a FATAL. Whether QZSS is enabled or disabled, the QZSS configuration is always "different":

[ublox_gps_node-1] [DEBUG] [1671498095.347203525] [ublox_gps_node]: QZSS Configuration is different 1, 1
[ublox_gps_node-1] [DEBUG] [1671498095.347210981] [ublox_gps_node]: QZSS Configuration: 286326785
[ublox_gps_node-1] [DEBUG] [1671498095.347217797] [ublox_gps_node]: QZSS Configuration: 286326785

This causes the node to determine that the configuration is not correct and reconfiguration is necessary. Reconfiguration always ends in a FATAL:

[ublox_gps_node-1] [FATAL] [1671498112.357696509] [ublox_gps_node]: Error configuring u-blox: Failed to cold reset device after configuring GNSS

To Reproduce Steps to reproduce the behavior:

1. Check out foxy-devel
2. Apply the git patch 0001-Edit-ZED-F9P-config-and-add-debug-statements.patch to the branch foxy-devel, which adds additional DEBUG statements, changes the default config to zed_f9p.yaml, increases the debug level to 2, and adds the additional config parameters:

    gnss:
      glonass: true
      beidou: true
      gps: true
      qzss: true
      galileo: true
      imes: false

3. Connect the ZED F9R device via USB, and note the port, which is likely /dev/ttyACM0. If not, note the device and edit the config zed_f9p.yaml to reflect the proper device.
4. Run the command ros2 launch unblox_gps ublox_gps_node-launch.py -d
5. Compare output of the node to the attached log zed-f9r-foxy-devel-cfg-debug.log
6. See error:

[ublox_gps_node-1] [FATAL] [1671498112.357696509] [ublox_gps_node]: Error configuring u-blox: Failed to cold reset device after configuring GNSS

Expected behavior

• It is expected that a ZED F9R with the ublox_gps node should start publishing ros topics with this config file, which enumerates all the enable/disable parameters for the GNSS configuration.
• It is expected that there is a value for gnss.qzss_sig_cfg which will cause the config to be determined to be correct, which there is not. See the log, which shows the intermediate values used in the logic for the configureUblox() function: https://github.com/KumarRobotics/ublox/blob/foxy-devel/ublox_gps/src/ublox_firmware8.cpp#L188-L191
• It is expected that an incorrect config and a cold reset does not always result in a FATAL

Desktop:

• OS: Ubuntu 20.04.5 LTS Focal Fossa (GNU/Linux 5.10.65-tegra aarch64)
• ROS 2 Foxy
• NVIDIA Jetson AGX Orin (ARMv8)

[vinaykumarhegde]

@duxroq Any leads on this? #147 could have been the problem as well.

[vinaykumarhegde]

Anyone looking at fixing this, two things that worked:

• configure the module on a x86 machine with latest gpsd ubxtool and set configure_on_boot: false;
• connecting ublox modules to hardware UART ports on the Orin/ARM module.

Chose the second one and things are working as expected now.