Arduino for STM32

For Vassilis (or anyone)

I see the 407 bootloader release on github, but am not clear what source file changes to make for a F401 build (WeAct borad "black pill").

There was a file with about 4 lines for the led pin and others, which made sense. After that I don't know.

Is this beyond most "hobby level" arduino types (me)?

STM32F401CCU6 (and F411xx) are going to be included in the 1.9.0 release. If you git clone the active repository, you can have access to these now.

Are you saying there is a HID 2 bootloader contained in the updated core (1.8+)?

F407 version looks like it was initially generated by cubemx
so as it HAL based, it's possible to port it for f401
but you need some skills to write proper clock init, replace ld script maybe and check all hw init cuz im not sure it's absolutely equal across F4 series
but, anyway, it's possible, most bl code parts can be kept untouched

OK, thanks stas2z, that is kind of what I thought.