bronco9588:
Do I loose anything with a higher frequencies? It just seems to purposeful that 16mhz is 2^4. Would serial monitor work?I still don't think the juice is worth the squeeze here... This is still chasing precision at the expense of accuracy.
Arduino uses 16MHz because it is dividable by 2 right down to 1. The accuracy is of the clock source, not the speed.
The chip core file used by the IDE has the value used to keep timing including baud rate correct. My 24MHz board second is the same as my 16MHz board second within tolerances of the clocks. I've run 328P's at 8MHz using an 8MHz core and 1 second is 1 second.
Where do you lose accuracy by running at 20MHz? For that matter, why not at least use a $12 48MHz Teensy LC? Or does removing "challenge" spoil things?