It was thus said that the Great drlegendre . once stated:
  @Sean
 I was wondering the same, but perhaps he needs physical hardware for some
 specific purposes, like timing and so forth? 
  The 6502 (as well as many of the other 8-bit CPUs of that era) are
deterministic to the point where published cycles counts for instructions
are an accurate measure of speed.  All you need is a cycle count to know how
fast a sequence of code is running.
  -spc