Arduino for STM32

Nice, thanks for sharing. How much flash space does it take?

i2c and SPI peripherals both can be used with the DMA controller, so they work independently of the CPU.
You could use DMA with one and the CPU (software) with the other, or both with DMA.

You best bet is probably to use the board name.
You can look in boards.txt for property build.board of the boards you plan to use.
From platform.txt, the board name will be used to create a macro name:
-DARDUINO_{build.board}

That means, for example, for board DISCO_F030R8, there property build ...

I haven't tested your code, so this is just a theory, but you if you are trying to fire interrupts at let's say 1Mhz, then the MCU has to be able, in 72 cycles (so 72 instructions), to:
Read the interrupt vector
Jump to that address
That addres most likely is part of the core, not your ISR, so it ...

Does anyone have the most current link for this HID bootloader?
Is it this one?
https://github.com/Serasidis/STM32_HID_Bootloader

Thanks!

I remember years ago when Ray posted about the $4 maple boards on aliexpress. Now the F4 board are that price.
The only problem I see with those, is that they have different pinouts vs the original bluepill and maple mini. The bluepillF4 designed in the old forum was pin compatible for the most part ...

Have you checked the official IDE?
https://www.st.com/en/development-tools ... beide.html

I built a couple, with F1, F4 and F7 MCUs.
Anyone still using and improving on them?
I have seen the F4 mini boards in aliexpress, but they each seem to have different pinouts.

Thanks Fedreric!
Glad to see the forum back online.

BTW I had a change to attend to an STM seminar in MEMS here is Austin recently, was great, love my little sensortile.