Absolutely! AVR is still reasonably easy to understand and manually bit-twiddle, but virtually all ARM cores are way too complicated for that. It is essentiall

Absolutely! AVR is still reasonably easy to understand and manually bit-twiddle, but virtually all ARM cores are way too complicated for that. It is essentially required to use a SDK to handle all the gory details for you. If you want to get a proper idea of what a modern ARM microcontroller architecture is like, I recommend you take a look at the RP2040 datasheet: https://datasheets.raspberrypi.com/rp2040/rp2040-datasheet.pdf https://datasheets.raspberrypi.com/rp2040/rp2040-datasheet.p...