old external Apple drive

From: Richard Erlacher <edick_at_idcomm.com>
Date: Wed Jun 13 12:29:05 2001

When my WD20AP unit is attached to an ADAPTEC AHA1542B under DOS and allowed to
boot with the drive turned on, it "sees" and reports the presence of a device,
WD-1006-something which it later reports it can't spin up.

It looks like it belongs to the late Apple-II/early MAC period, being shaped and
colored to match. (take the color info with a grain of salt, though, since I'm
"chromatically challenged.")

It's pretty clearly a SCSI device, else the SCSI controller (AHA1542B) would not
be able to communicate with it via the SCSI-1<=>DB25 (Comonly used with Apple
SCSI ports) adapter cable.

I wouldn't bet on a healthy result attaching the device to anything not SCSI.
It's possible that my unit had a dead drive in it, at least if there's a bridge
controller, which I'd readily believe, but if there's a bridge, it probably
wants to be set up, i.e. told what sort of drive it's got, which has to happen
from the outside if it can't readily read the drive info from the drive itself,
in most cases. Now, a couple of other Apple type external drives with which
I've experimented have had customed firmware that prevents the bridge controller
from behaving as similar models would behave, possibly requiring that they see
the Apple setup routines before doing anything. I'm not at all certain about
that.

Dick

----- Original Message -----
From: "Eric Chomko" <chomko_at_greenbelt.com>
To: <classiccmp_at_classiccmp.org>
Sent: Wednesday, June 13, 2001 6:01 AM
Subject: Re: old external Apple drive


>
>
> Mike Ford wrote:
>
> > >> I recently was given a Western Digital Hard Disk 20AP, obviously
> > >>intended for
> > >> use with an Apple computer of some sort. It identifies itself as a
Western
> >
> > Why do you say obviously intended for use with an apple? I don't recall
> > anything by WD that was for an Apple, or even Apple friendly. 20AP sounds
> > more to me like some old parallel interface PC thing.
>
> I have the WD 40AP. It uses a DB-25 connector and I thought that it was SCSI,
but
> wasn't convinced for sure. I do remember I didn't find much on the web for it
one
> way or another. Does anyone know if its SCSI or TTL parallel? Any other info?
>
> Eric
>
>
>
>
>
Received on Wed Jun 13 2001 - 12:29:05 BST