Re: Apple II 256K Memory Expansion Kit

["mdj" <mdj.mdj@gmail.com>]

On Feb 25, 5:14 pm, "Payton Byrd" <plb...@bellsouth.no.spam.net>
wrote:
> What is the correct memory card to install the Apple II 256K Memory Expansion Kit into?  The kit consists of eight (8) TMS4256 chips.  I've added them to my AIIE 80COL/64K memory expansion board for my IIe, but it still shows 128k in ProDOS (1.0.8) slot utility.  Does Apple have a newer memory expansion that these chips are intended for?

The official 'Apple' branded kits were intended for either a) The
Apple II memory Expansion Card (slinky) b) The Apple IIgs memory
expansion card c) The Apple IIc memory expansion card

Being run-of-the-mill 256kx1 RAMs, they'll also work quite well in
RamWorks cards, other 'Slinky' adapters, and possibly other IIgs
expansion cards.

> Also, what is J1 for on the AIIE 80COL/64K memory expansion board?  It appears to complete a circuit from pin 55 to pin 11 of the auxiliary port.  Is that possible for a hard reset switch, or maybe some kind of optional LED?

I've never looked up the exact 'technical' need for this jumper, but
it is necessary due to the hardware change that introduced double hi-
res graphics - I believe installing the jumper will inhibit 14Mhz
video when a graphics mode is active, which is necessary to prevent
hardware lockups on the revision A Apple IIe (which doesn't support
double resolution graphics modes)

Someone else here probably knows the exact details of why this change
is necessary.

Matt