The core arduino environment is not very hard to port to other CPUs, but it might be more useful to point out that by the time you're capable of doing that, you'd probably also be capable of writing apps for the other CPU in "raw gcc" that didn't require any of the arduino environment.
You are right,There are AVR tutorials i shall read over and i'll continue to use Arduino for prototyping as intended.
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That last sentence undervalues the Arduino somewhat, so i must say that Arduino & it's resources including this forum have been invaluable to me & the Arduino environment facilitates so much more.
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