Shawn Hearn wrote:
"Bible John" <john.doggett@x-files.gov> wrote:The second major architecture change came in 1994 when Apple moved from the 68000 CPU to the IBM PPC CPU. Hardware would still work in the PPC Macs, and over 90% of 68K apps would work on a PPC. Even today I run many 68K apps on my ibook G4.This was the first CPU design change.
I seem to recall that the Mac was originally developed around a Motorola 6809 and then switched to the 68000 for performance reasons. The 68000 to 68020 to 68030 to 68040 changes weren't without hiccups, either; the onboard MMU and FPU led to a variety of incompatibilities back in the days.
But regardless, I've largely become ISA agnostic because little of my work is done at the level where the features of the CPU make a difference. And I'm an embedded developer :)
Kelly