old external Apple drive

From: Don Maslin <donm_at_cts.com>
Date: Wed Jun 13 18:04:58 2001

On Wed, 13 Jun 2001, Richard Erlacher wrote:

> 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.

Interesting and confusing! The WD-1006 series that I am familiar with
were all either ISA or MCA cards with either MFM or RLL ST-412 drive
interface.

> 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.

That is hard to argue with!

                                                 - don

> 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 - 18:04:58 BST