STM32CubeF4 VS qmk_firmware

2b. I think the more interesting thing for you to look at is the linker script (example). This tells the linker where to put sections (data, bss, rodata, etc). Here you can see where exactly the isr_vector goes and the section it comes from

Most chip vendors offer a "HAL" or hardware abstraction layer, which is basically a set of functions and defines that does all of this low level stuff. Here's an example of one for STM32F4 chips. The CMSIS folder contains code that is common to most ARM Cortex-M devices, and the STM32F4xx_HAL_Driver folder contains the actual HAL. And here's an example of a startup script and a linker script.

St HAL had and still have huge issues, there is no repo for the code, so you need to download the zip, and for a long time there was not even a issue tracker, I had many time issues and found out someone on the forum reporting the problem. Now at least we have issue tracker, but that made mode clear there are some interesting decision, like missing volatile and no plan to fix it: https://github.com/STMicroelectronics/STM32CubeL4/issues/30 https://github.com/STMicroelectronics/STM32CubeF4/issues/10

Download the firmware package for your series. Here is the F4 series. Look under the "projects" folder.

Lastly, and I think these were the hardest things to find when I was transitioning away from Keil, is all of the vendor-specific and compiler-specific “glue” like startup files and linker scripts. For example, STM32F4 startup, system config, and linker scripts can be found here for various MCUs

There's an open issue if you're interested in tracking progress on it.

This 1.5Y old ticket proves the point https://github.com/STMicroelectronics/STM32CubeF4/issues/10 (do not hesitate to upvote this one as everybody agrees it needs to be modified).

I think this would be the preinstalled program: https://github.com/STMicroelectronics/STM32CubeF4/tree/master/Projects/STM32F429I-Discovery/Demonstrations/TouchGFX

That's where I would begin for building new projects for interfaces and peripherals I don't already know well. However when you are just starting out with something, it can be even easier to modify a working example. Here's a source for official ST USB examples on STM32F4 MCUs: https://github.com/STMicroelectronics/STM32CubeF4/tree/master/Projects/STM32446E_EVAL/Applications/USB_Device

Clone STMCube repo https://github.com/STMicroelectronics/STM32CubeF4

I only use keyboards running QMK or ZMK, so:

My Caps Lock key is a Control/Escape key (when tapped it behave like a Escape, when hold it's Control), and my left Control is a one shot layer switch key [1], which means I tap LCtrl once, and then press Caps Lock + 5 to get Ctrl+F5. Doable with single hand and more ergonomic as I have an unusually small hand.

[1] https://github.com/qmk/qmk_firmware/blob/master/docs/one_sho...

I agree that reduced finger movement is a crucial step in achieving typing efficiency. This is nicely solved by mod tap modifiers in QMK/ZMK[1] where key acts as a char when tapped and as a layer while pressed.

[1]: https://github.com/qmk/qmk_firmware/blob/master/docs/mod_tap...

Separate wireless controller, see the glue code at [0]

[0]: https://github.com/qmk/qmk_firmware/compare/master...nuphy-s...

If you have a keyboard that runs QMK firmware[0] with the VIA[1] feature enabled[2], then there is a convenient testing app available from the same place you customize your keys [3].

[0] https://qmk.fm/

I made a layout that I'm happy with. Spanish is my native language, so it has characters like the accents and 'ñ', but it's meant to be used for programming as well. Visual Studio uses a lot of Ctrl and Ctrl + Shift shortcuts, so I left them in the same place as the default Corne layout so I can press them both with my pinkie finger. Perhaps some of the ideas are useful to you.

Also, it would be possible to do this for the RP2040. However, it needs some work to get working. but for example: https://github.com/qmk/qmk_firmware/pull/20999

Ok, it's an ST7735, not too different from the ST7789. You should be able to get running by looking at their files in the QMK repo and going from there. You should also check their resources page.