Re: Information about this SRAM card

["Bryan Villados" <news002@macgeek.org>]

Cool! That's quite a bit of information. I'm especially interested in the
copyright wording on the card "The Engineering Dept." which I've never seen
before on anything else retail, which would lead me to believe it may be
something that's pre-production, such as a prototype.

--- Bryan

"David Empson" <dempson@actrix.gen.nz> wrote in message
1flifz4.1jrl7e3maxdc0N%dempson@actrix.gen.nz">news:1flifz4.1jrl7e3maxdc0N%dempson@actrix.gen.nz...
> Bryan Villados <news002@macgeek.org> wrote:
>
> > I've never seen this card before....
> >
> > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2070773121
> >
> > Could someone post a write-up about this card? Thanks! :)
>
> I've never seen one of these cards before.  The only visible components
> are two 8 KB static RAM chips and a PAL (logic chip).  It is obviously
> made by Apple, given the logo and corporate font.
>
> Given that it contains 16 KB of RAM, I expect it is supposed to be
> compatible with a language card.
>
> The only useful reason I can think of for it containing static RAM as
> opposed to dynamic RAM is that the contents of the RAM would be
> preserved if the computer stopped refreshing memory for some reason, but
> the only time it does that is when it is switched off, and the static
> RAM contents would be lost along with everything else.  If it had a
> battery backup option, it would make more sense.
>
> It would also consume less power than a card with the same amount of
> dynamic RAM, but that is pretty minor in comparison to the rest of the
> computer.
>
> According to the seller, it came from a IIe, which is possibly a
> counterargument to it being a language card, as the IIe would have no
> need for such a card.
>
> It might be some kind of prototyping card, which has read/write access
> to the $Cn00 and $C800-$CFFF space, with bank switching to provide
> access to the rest of the RAM.
>
> --
> David Empson
> dempson@actrix.gen.nz