Date   : Tue, 30 Dec 1986 00:29:13-MST
From   : "Frank J. Wancho" <WANCHO@SIMTEL20.ARPA>
Subject: Cheap PC hard disks for old S-100 system?

With all those ads for dirt-cheap high-capacity hard disk drives
(relative to just a few years ago), just what would I need to buy to
hook one of those drives to my S-100 NorthStar Horizon, mostly running
TurboDOS these days?  What interface do most of these drives use/need?
Are they mostly ST-506-compatible, or SCSI, or what?

I have several ways to go depending on the answer.  For example, if
they were ST-506, I could probably get a TurboMaster card with a
built-in ST-506 interface and the TurboDOS drivers to go with it.
(The catch is that I haven't yet heard of a mod for it to allow me to
block out the 1K I need at the top of Bank 0 so I can keep my N* disk
controller in the system.)  Other hard disk controller cards pose
problems of their own, such as one of the old Morrow cards or the
CompuPro DISK3 - i.e., some know historical problems with these cards
on the N* S-100 bus with the N* ZPU card, plus the possible lack of
TurboDOS drivers to support them.

Now, if these drives can use the so-called SCSI interface, perhaps I
can consider using the AMPRO SCSI add-on, if they still sell it.  But,
as I recall, it wasn't quite up to the full SCSI spec - something
about limits on the number of devices or device addresses or somesuch.
That, of course, may be academic if you only plan to hook up one or
two of these drives.

In any event, the question remains: what interface do these cheap hard
drives expect?  (What do they expect if you don't buy the PC interface
card normally sold with these drives?)  I'll compile a list of brand
name, model number, interface, and recommendation when and if I
receive sufficient replies.

Thanks,
Frank