Anyone have any experience replacing a Dallas 1287 with a 128 87?

From: Feldman, Robert <Robert_Feldman_at_jdedwards.com>
Date: Thu Jan 2 09:15:01 2003

There are 3 memory expansion slots. When filled with 4MB modules, the max
RAM is 12.6MB.

Three hard drives were offered: two 20MB (type 2) and one 40MB (type 22).
The difference between the 20MBs was the interleave of 1:1 vs 3:1.

The Compaq Service Quick Reference Guide (1992) lists 13 different ROM
revisions, from F.2 to K.1

-----Original Message-----
From: Ethan Dicks [mailto:erd_6502_at_yahoo.com]
Sent: Wednesday, January 01, 2003 4:51 PM
To: cctalk_at_classiccmp.org
Subject: Re: Anyone have any experience replacing a Dallas 1287 with a
12887?



--- Tothwolf <tothwolf_at_concentric.net> wrote:
> Years ago I used to maintain some of these systems...
> The memory modules are located center-front of the "laptop", under a
> metal shield/cover.

Yep. Found those. Full of SRAM, not DRAM, astonishingly enough.

> I don't remember how many slots exist, but I think it can
> hold 3, maybe 4 modules. Modules were available in 1MB and 4MB sizes.

Three. I have three 1MB modules. Didn't know there were 4MB modules.
I'm sure I'll never run across any. For DOS usage, 3.6MB is OK. This
one has Windows 3.0 on it, but I don't need it for what I'm doing.

> The hard drive is a 3.5" form factor IDE drive. Usually, these systems
> had a 20MB or 40MB drive, but it would have been possible to upgrade
> it to 120-210MB too...

Mine has the bog-standard 40MB Connor drive (type 22). Would love to
find a set of replacement ROMs for this so I could use oddball drives,
but for now, I'm stuck with what I've got.

-ethan
<snip>
Received on Thu Jan 02 2003 - 09:15:01 GMT