One of the things I am looking into is to have a bootloader through LoRa. Making one is straight forward, but I actually think I can use the build.in silicon bootloader as is…
You probably know that all STM32 MCU’s comes with a build-in bootloader in ROM located at a special address. You invoke this by using boot pin, but less known is that you actually can call this manually from firmware. in my case I have LoRa connected to USART, and accessing this from a PC I should be able to use the build-in bootloader over LoRa and use ST’s own utilities.
The trick here is that neither the serial line on MCU or PC actually see the LoRa in the middle. The LoRa unit I use can be configured once and will afterwards just work using that setting. I obviously need to create an adapter for my PC as well (or buy one), but that should be doable.