Last month (https://dayjaby.wordpress.com/2020/03/02/february-2020-collecting-ideas/) I collected some ideas regarding software/hardware projects. This month I would like to focus on designing an own PCB containing a STM32F4.
What I would like to achieve/learn:
- infer good practices from other designs
- have a working example (using breakout boards in the first step)
- close the gap between hardware and software
- use the STM32 as an USB to UART bridge (https://mikrocontroller.bplaced.net/wordpress/?page_id=729)
- combine an STM32 with some other module on one board (e.g. https://github.com/sixfab/Sixfab_RPi_3G-4G-LTE_Base_HAT)
STM32F4 is able to run NuttX RTOS. In the following video we learn about some USB capabilities of NuttX. https://www.youtube.com/watch?v=rgZJPZh_po8. CDC/ACM addon for NuttX: https://github.com/jodersky/nuttx/tree/master/apps/system/cdcacm
In the PX4 Firmware we find following CDC/ACM settings:
CONFIG_CDCACM_PRODUCTSTR=”PX4 FMU v5.x”
The USB host can see the device as /dev/ttyACM0. On NuttX side, data can be sent/received via /dev/ttyACM0 as well.