rosbot-firmware

STM32F4 firmware for ROSbot 3 and ROSbot XL. The MCU talks MAVLink v2 (rosbot dialect) to the SBC, where rosbot_mavlink_bridge turns it into the ROS 2 API described in ROS_API.md. One .bin per robot serves every ROS 2 distro the bridge is built for.

micro-ROS support was removed after v2.1.0-jazzy. Up to that release the firmware could also run a micro-ROS (XRCE-DDS) stack against micro_ros_agent, chosen at boot by the BACKEND: handshake line. It is still in git history; the firmware now answers BACKEND:microros with NAK.

Build and flash

Day-to-day workflow on the ROSbot SBC uses just:

just install-deps         # one-time: pymavlink + platformio in a venv
just build rosbot_xl      # one env; envs: rosbot[_xl], rosbot[_xl]_release
just build-all            # all four envs
just flash rosbot_xl      # builds and flashes via rosbot_utils
just mavgen               # regen MAVLink dialect headers
just --list               # every recipe

just flash wraps ros2 run rosbot_utils flash_firmware; see CONTRIBUTING.md and scripts/flash.sh.

Run the SBC side

# rosbot_xl (Ethernet, mavros default ports)
ros2 launch rosbot_mavlink_bridge rosbot_xl.launch.py namespace:=rosbot

# rosbot (Serial)
ros2 launch rosbot_mavlink_bridge rosbot.launch.py namespace:=rosbot \
  --ros-args -p serial_port:=/dev/ttyS4

The bridge advertises the /<ns>/rosbot_mcu node that rosbot_ros (snap) consumes.

Internals

• ARCHITECTURE.md — firmware architecture, RTOS task layout, transport patterns, MAVLink stack.
• ROS_API.md — ROS topic / service contract.