Chips that changed the world

[Joachim Thiemann]

On Sat, May 2, 2009 at 15:38, Brent Hilpert <hilpert at cs.ubc.ca> wrote:
> Tony Duell wrote:
> Keeping in mind as well, that at the the time of the 68000 release ca. '79/80,
> 16MB=2^24 was a lot of memory. Going beyond 16-bit physical addressing was
> warranted in terms of market/economics, the same could not be said for 32-bit
> physical addressing for a microprocessor system. 24 bits was a practical
> goldilocks solution.
>
> The 32-bit initial architecture provided for future upgrade/compatibility, and
> was addressed (pun) in later versions.

Then of course there were those programmers that thought they were
clever, using the top 8 bits to store flags in pointers, etc.  Royally
messed up when upgrading to 68020 and up.

Somehow this seemed only a problem on Macs - the "dirty" ROMs issue on
the SE30 and some others.  I don't recall the Amiga ever having those
issues, and I have no clue about the Atari...

Joe.
-- 
Joachim Thiemann :: http://www.tsp.ece.mcgill.ca/~jthiem