Re: A86: Asm-86 12k cap
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Re: A86: Asm-86 12k cap
Hmm....
In a message dated 4/29/98 9:15:40 PM Central Daylight Time,
assets@eden.rutgers.edu writes:
> Can a RAM page be put out port 5? I know that a ROM page can be put out
port
> 6.
>
> If you put the first 12k out port five, you could add another 16k using
port
> 6.
> The only
> problem is that the ROM call emulation would probably have to be changed (
> not
> having
> page $0d), but since you would have to check for ROM versions, you could
use
> that
> call on page 0 that swaps the page back after it's finished or just use the
> calls on page
> 0. Who knows? ... that might even get it to emulate faster.
>
> Kirk Meyer wrote:
>
> > that's not possible. the way 85 programs are simulated is an 85-like
> > environment is created from $8000-$BFFF in the 86 memory on RAM page 1,
> > which can be used for this purpose. since program execution on an 85
> starts
> > at about $9000 (or even later), this leaves only 12K of RAM page 1 to be
> > used by programs. you cannot use beyond the $BFFF address because $C000
> is
> > used by _getky routines and even if you move that data somewhere else
> > temporarily, lots of things would be corrupted (if you didn't understand
> > that sentence, that's good, 'cause neither did I :)
> >
> > Kirk
> >
> > Lifoo wrote:
> >
> > > Does anyone know of a shell of prog that removes the 12k CAPof progs.
> > > There are many games for the 85 and 83 that won't run on the 86 because
> > > they are too large. If there isn't a prog like that. Then I think
that
> > > that would be a good idea.
>