Re: What do I do next?

[dempson@actrix.gen.nz (David Empson)]

Byron Desnoyers Winmill <wbdesnoy@acs5.acs.ucalgary.ca> wrote:

> In article <a453h9$6vv$1@venus.itns.co.za> you wrote:
> : Not necessarily so! It might be the plain vanilla 80 column card
> : WITHOUT the extra RAM.
> 
> I was given the erroneous impression by the simplicity of these cards
> that the IIe was simply using some of this additional memory to support
> 80 column mode.
> 
> So how does the 80-column card work?

There are two variants of the IIe 80-column card:

The "standard" 80 column card has 1 KB of RAM, mapped at memory
locations $0400 to $07FF in auxiliary memory.  It provides sufficient
RAM to support 80-column mode, but nothing else.

The "extended" 80 column card has 64 KB of RAM.  This allows the use of
80-column mode, double hi-res graphics, the ProDOS auxiliary memory RAM
disk, and any applications which require 128 KB of RAM.

The early versions of these cards used 1Kx4 and 64Kx1 RAM, so the
standard 80-column card has about five chips (including two RAM chips)
and is a little longer than the slot, while the extended 80-column card
has about eleven chips (including eight RAM chips) and is considerably
longer than the slot.

By the time the "platinum" IIe was released, Apple had switched to using
64Kx4 RAM chips, resulting in a much smaller extended 80-column card
(about an inch high, and just as long as the slot).  I believe this was
supplied with the machine, so the standard 80-column card was only of
use in older machines.

-- 
David Empson
dempson@actrix.gen.nz