No - can't use it for ZX128 paging - as SAM's is rather different layout
----- Original Message -----
From: "Aley Keprt" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Friday, August 03, 2001 11:22 AM
Subject: Re: External memory on Sam
> It is a great piece of hardware.
> Similar to Amiga. Only CPU access, but well pageable, usable to achieve
6MHz
> speed, and allows to emulatoe ZX Spectrum 128 paging. Am I right.
>
> Master Dos seems to use it for its own.
>
> That is probably what I talked about recently. Simon Cooke wrote that I am
> missing the point, when wanting this from 80's designed computer Sam
Coupe.
> But here I can see it is real. So why don't we have at least 256KB
internal
> memory made of this external one?
>
> ------------------------------------------------------------------
> Bc.Aley [eili] Keprt - games & multimedia programmer
> ICQ: 82357182 (evenings) *** phone: +420-68-5387035 (weekends)
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>
> ----- Original Message -----
> From: "Simon Owen" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: 3. srpna 2001 12:02
> Subject: RE: External memory on Sam
>
>
> > Aley Keprt wrote:
> > > Is external memory contended?
> >
> > Nope.
> >
> >
> > > Or how does it work? Is it possible to page it into 64KB CPU
> > > space, and then let CPU run at 6MHz in there?
> >
> > Well, it can only be mapped into the upper 32K, not the full 64K address
> > space (still be good enough for a lot of stuff). Depends whether you
> > were thinking about general programs using it, or getting the BASIC
> > system to use external memory instead of contended system RAM. The
> > display will always be in system RAM, so you'd have to write to it in
> > the border area to escape as much contention as possible!
> >
> > Not many people have external RAM though, so I can't imagine any
> > existing software would/could rely on it for the extra speed. It'd
> > certainly screw up fancy demo timings too!
> >
> > Si
> >
>
>
>
