micro-ROS not publishing or subscribing to topics

edit

I'm following these guides here:

https://github.com/micro-ros/micro_ros_setup
https://micro.ros.org/docs/tutorials/core/first_application_rtos/freertos/

Host:

Ubuntu 20.04
ROS2 Foxy

Board:

STM32 Nucleo-144 F767ZI

Firmware created with:

ros2 run micro_ros_setup create_firmware_ws.sh freertos nucleo_f767zi

Firmware configured with:

ros2 run micro_ros_setup configure_firmware.sh ping_pong --transport serial

micro-ROS agent is run with:

ros2 run micro_ros_agent micro_ros_agent serial --dev /dev/serial/by-id/usb-STMicroelectronics_STM32_STLink_0672FF3530384E5043161319-if02

Note: The board is connected via microUSB (Board) to USB (Host) and the --dev flag allows for hitting the TAB key on the keyboard, which already suggests the correct serial port to the STM32_STLink.

[1631436844.462724] info     | TermiosAgentLinux.cpp | init                     | running...             | fd: 3
[1631436844.463369] info     | Root.cpp           | set_verbose_level        | logger setup           | verbose_level: 4
[1631436846.283707] info     | Root.cpp           | create_client            | create                 | client_key: 0x1247AB10, session_id: 0x81
[1631436846.318823] info     | SessionManager.hpp | establish_session        | session established    | client_key: 0x1247AB10, address: 0
[1631436850.012475] info     | SessionManager.hpp | establish_session        | session re-established | client_key: 0x1247AB10, address: 0
[1631436858.425578] info     | SessionManager.hpp | establish_session        | session re-established | client_key: 0x1247AB10, address: 0

Note: a few minutes pass between the previous and the next line.

[1631437271.578840] info     | SessionManager.hpp | establish_session        | session re-established | client_key: 0x1247AB10, address: 0
[1631437275.106846] info     | SessionManager.hpp | establish_session        | session re-established | client_key: 0x1247AB10, address: 0
[1631437337.350620] info     | SessionManager.hpp | establish_session        | session re-established | client_key: 0x1247AB10, address: 0
[1631437361.529819] info     | SessionManager.hpp | establish_session        | session re-established | client_key: 0x1247AB10, address: 0
[1631437403.083854] info     | Root.cpp           | delete_client            | delete                 | client_key: 0x1247AB10
[1631437403.083934] info     | SessionManager.hpp | destroy_session          | session closed         | client_key: 0x1247AB10, address: 0

Since this is the ping_pong example, ros2 should be able to echo the /ping topic while the connection is open:

ros2 topic echo /microROS/ping

However, this command results in:

WARNING: topic [/microROS/ping] does not appear to be published yet
Could not determine the type for the passed topic

Edit: increased verbosity level to 6

$ ros2 run micro_ros_agent micro_ros_agent serial --dev /dev/serial/by-id/usb-STMicroelectronics_STM32_STLink_0672FF3530384E5043161319-if02 -v6
[1631959197.450823] info     | TermiosAgentLinux.cpp | init                     | running...             | fd: 3
[1631959197.451169] info     | Root.cpp           | set_verbose_level        | logger setup           | verbose_level: 6
[1631959201.133528] info     | Root.cpp           | create_client            | create                 | client_key: 0x1247AB10, session_id: 0x81
[1631959201.133756] info     | SessionManager.hpp | establish_session        | session established    | client_key: 0x1247AB10, address: 0
[1631959201.134067] debug    | SerialAgentLinux.cpp | send_message             | [** <<SER>> **]        | client_key: 0x1247AB10, len: 19, data: 
0000: 81 00 00 00 04 01 0B 00 00 00 58 52 43 45 01 00 01 0F 00
[1631959209.370283] debug    | SerialAgentLinux.cpp | recv_message             | [==>> SER <<==]        | client_key: 0x1247AB10, len: 24, data: 
0000: 80 00 00 00 00 01 10 00 58 52 43 45 01 00 01 0F 12 47 AB 10 81 00 FC 01
[1631959209.370532] info     | SessionManager.hpp | establish_session        | session re-established | client_key: 0x1247AB10, address: 0
[1631959209.370753] debug    | SerialAgentLinux.cpp | send_message             | [** <<SER>> **]        | client_key: 0x1247AB10, len: 19, data: 
0000: 81 00 00 00 04 01 0B 00 00 00 58 52 43 45 01 00 01 0F 00