[Coco] Re: 64K Mode

[Paul T. Barton]

--- "John E. Malmberg" <wb8tyw at qsl.net> wrote:
> jdaggett at gate.net wrote:
> > John
--snipped-- 
> We are basically saying the same thing.
> 
> You have a choice of 64K Dynamic RAM, or upper
> 32K ROM/static RAM and 
> either the upper or lower 32 K of the 64K
> Dynamic RAM in the lower.
> 
> The 32K segment where the ROMs normally reside
> could also have static RAM in it.
> 
> It should be possible to run a second copy of
> BASIC in the other 32K 
> with an interrupt or other means to switch
> between them.
> 
> -John
> wb8tyw at qsl.net
> Personal Opinion Only

We used to do this very thing.
Load a program into the low 32k,
under program control switch pages
and run an identical program (with a
screen color to identify it) while
it switched back & forth between
32k pages (on the fly). {whew!}

Another ttl scheme allowed another
64k piggybacked dram that allowed
4 (four) pages of 32k in the low area.
You could run 4 different BASIC programs
on the fly while switching 32k pages.
I did this one too.

Paul T Barton


__________________________________
Do you Yahoo!?
Yahoo! Hotjobs: Enter the "Signing Bonus" Sweepstakes
http://hotjobs.sweepstakes.yahoo.com/signingbonus