HP 9825 configurrationss

From: Doug Yowza <yowza_at_yowza.com>
Date: Thu Jun 18 02:50:49 1998

On Wed, 17 Jun 1998, Joe wrote:

> For anyone that cares, here is a list of the configurations of my HP
> 9825s. Notice there's some funny stuff here. Some are marked 9825A on the
> back but 9825B in the front next to the display. Several are marked 9825T
> under the paper cover. #4 says A on the back, B next to the display and T
> under the cover! You figure that one out!

Bastards! I just opened mine up (it's pretty inside) and it's a bastard
too. AFAICT, it started life as a 9825A in 1979 and then got upgraded to
a B/T sometime in 1982 or later. It has the long channel for the system
ROM you described, but the channel is plugged, and I assume one of the
newer boards in the stack replaces that ROM.

BTW, mine seems pretty maxed out: 9872A plotter, general I/O, extended
I/O, adv. programming, string, system programming (sounds cool), total
memory 61670 (+ matrix cart).

Fixing my stuck "execute" key looks like it'll be a bastard too. It's not
stuck, the "snap" mechanism appears to be simply gone (not easily
explained since the keyboard appears to be a tight sandwich). I hope that
key isn't important in the big scheme of things, but I have a nagging
suspicion that it's needed to program.

BTW, one of the prettier chips looks like it's either the keyboard
controller or a ROM: a 40-pin white ceramic number labeled H1818 2508
6672.

-- Doug
Received on Thu Jun 18 1998 - 02:50:49 BST