Comment by ChuckMcM

I hope nobody was confused into thinking I thought a BIOS was required, I was pointing out the evolution from this to a monitor. I've written some code[1] that runs on the STM32 series that uses the newlib printf(). I created the UART code [2] that is interrupt driven[3] which gives you the fun feature that you can hit ^C and have it reset the program. (useful when your code goes into an expected place :-)).

[1] https://github.com/ChuckM/

[2] https://github.com/ChuckM/nucleo/blob/master/f446re/uart/uar...

[3] https://github.com/ChuckM/nucleo/blob/master/f446re/common/u...