Re: IIgs peculiarities

[dempson@actrix.gen.nz (David Empson)]

Charlie <charlieDOTd@verEYEzon.net> wrote:

> "David Empson" <dempson@actrix.gen.nz> wrote in message 
> 1ivk1t0.1hybb3evsti5lN%dempson@actrix.gen.nz">news:1ivk1t0.1hybb3evsti5lN%dempson@actrix.gen.nz...
> > vladitx <vladitx@nucleusys.com> wrote:
> 
> > SNIP <
> 
> >> 3) IIgs maximum RAM - banks $00 .. $7F are specified as RAM range.
> >> This makes exactly 8MB. But the manuals keep saying 8.25MB. What is
> >> the truth and where those 256KB came from?
> >
> > Anything saying 8.25 MB is simply wrong. The correct figure is 8.125 MB
> > (8 MB plus 128 KB).
> >
> > The extra 128 KB is the "slow" memory in banks $E0 and $E1.
> >
> 
> Isn't there another 128KB of RAM dedicated to the sound generation chip?

Yes, but it isn't memory mapped into the CPU's address space, so it
doesn't really count.

-- 
David Empson
dempson@actrix.gen.nz