I am working on a measurement device project based on a STM32G4 which is currently not based on ROS at all. Due to future changes to implement the device in a larger quantity in an array configuration, I am considering using micro ROS for network and data managing and to improve the scaling.

Since I am completely new to ROS as well as TCP/IP (Ethernet over twisted pair) on uController I wanted to ask for advice or stupid design mistakes commonly done. My imagination is to connect 10-20 devices using 10Base-T, including a host computer, porting the existing code base (based on FreeRTOS) to uRos.

My questions:

1. Which uCon is best suited for this task? I have a lot of experience with STM, however I dont have any knowledge about the compatibility with ethernet. Is it as simple as just adding a ethernet IC? The ESP32 does support wireless however is it more compatible then STM chips with ethernet? (https://github.com/micro-ROS/micro_ros_setup here it is written, that the esp32/uRos is not compatible with ethernet)

2. Do I need to use specific ethernet ICs compatible with uROS? Do I need to copy the layout of the olimax STM32-E407? For our project a custom PCB is necessary due to space constrains.

3. Are there some exemplary project (other then https://github.com/husarion/micro_ros_stm32_template)?

4. I guess UART is not really feasible for 10 - 20 devices since I need to connect them all individually to the host PC, or can they be interconnected so in total only a single UART connection is necessary? (Due to the environment of my project wireless is a no go)