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Re: IIc Memory..



vladitx wrote:
On Feb 2, 6:42 am, Mitchell Spector <mitch...@hotmail.com> wrote:


   There is an easier way to report the total installed memory, and
it's built-in to the IIc. The memory expandable IIc (ROM 3 and higher)
has same firmware as the Apple II Slinky RAM card, which is present
whether you have a memory card installed or not.


Maybe you can help me solve my confusion on this topic. :-)

The AE Z-RAM IIc memory expansion card (and few others) use the
RamWorks approach with bank-switched aux memory. The Slinky cards, on
the other hand, are usually indirectly addressable through 24-bit
pointer (a-la RamFactor).

So, which one is used for the official Apple IIc memory expansion
card, which is plugged into the dedicated connector on A2S4100 boards?

As Sean noted, the Apple expansion card is a Slinky.

Apple never made a bank-switched card (not counting the original
16K card with its "mini-bank").

Third parties did all the multi-banked cards, probably because it is
such a straightforward way to do the extension, and it allows the
extended memory to function as normal RAM when it is switched in.

The Slinky design only provides efficient sequential access to the
expansion memory, and is therefore best suited for RAM disks and
certain "swapping"-style memory managers, like Appleworks uses.

In fact, I've always theorized that the Slinky design was inspired
by Appleworks, which was the premier Apple II app that could benefit
from memory expansion.

-michael

NadaNet and AppleCrate II: parallel computing for Apple II computers!
Home page: http://home.comcast.net/~mjmahon

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