[Coco] OSK, 68K question

Willard Goosey goosey at virgo.sdc.org
Mon May 24 15:46:13 EDT 2010


On Mon, May 24, 2010 at 09:10:51AM -0400, Gene Heskett wrote:
> On Monday 24 May 2010, Willard Goosey wrote:
> >So, I was reading http://www.folklore.org/ about the creation of the
> >Macintosh, and came across the comment that the 68000's relative jump
> >only has a range of 32K.
> >
> Wow!  That sounds as bad for what was supposedly a 24 bit cpu, 

I was willing to accept the idea, since I know (from other sources)
that MacOS allocates memory in "segments" <=32K.  OTOH the same site
said that the 68K had the same sort of bus as the 68xx and 65xx,
so....

And the docs I have on 68K assembly says that's a +/-32K range -- a
16-bit offset.  020+ can do 32-bit offsets, at the expense, of course,
of another full memory cycle to load the offset.

> >And I started wondering, what effects this had on OSK?

Besides an attitude of "break your humongoid app into modules, which
has lots of other advantages, idiot!", of course. :-)

Willard
-- 
Willard Goosey  goosey at sdc.org
Socorro, New Mexico, USA
I search my heart and find Cimmeria, land of Darkness and the Night.
  -- R.E. Howard



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