[Coco] hard drive questions

[Chester A. Patterson]

The RLL spec on the Seagate I got from their www. The connector
looks just like your common EIDE interface (as do the other two
drives) The Drive itself says very little of help on the label.
I plugged it into the PC anyways (!) and the BIOS coughed up
Incompatible IDE after thinking about it a few seconds.

-----Original Message-----
From: L. Curtis Boyle [mailto:curtisboyle at sasktel.net]
Sent: Monday, June 12, 2006 2:49 PM
To: CoCoList for Color Computer Enthusiasts
Subject: Re: [Coco] hard drive questions

On Mon, 12 Jun 2006 14:00:37 -0600, Chester A. Patterson
<vchester at setec-cr.com> wrote:

> Hi,
>
> I've collected some hard drives for when I get an IDE adapter. Thye have
> the ubiquitous standard dual in-line 40 pin connector. They were pulled
>  from (I'm told) working 286 and 386 PCs.
>
> The Conner I think is dead 'cause it sounds like it speeds up and slows
> down, after 5-10 minutes it appears to settle into a fixed speed. Intel
> BIOS doesn't even acknowledge its existence. The Quantum is my favorite
> for eventual use with Coco but Intel BIOS returns "NOT IDE Compatible
> Disk" Google search finds very little on this specific model, others
> similar yes.
> The Seagate is RLL. I guess I need a special interface for it. Haven't
> plugged it into the PC.
>
> Quantum HD LPS270A 257mb "AT interface" 12ms  Cyl.944 (800) Hd.14 Sec.40
> Seagate HD ST157A1 45mb "AT interface" RLL (2,7) Cyl.560 Hd.6 TPI.824
> Conner HD CP30061 "AT interface" Type 55
>
> How to check them? Should I toss or keep? Thanks!
>
> /Chester Patterson
>
    If you end up running an IDE driver that supports the last options I
did on it, the Detect IDE program I wrote for it should be able to tell
you if it will work or not. Some older IDE drives did not exactly follow
the spec (and lied about things like cylinders, sectors and heads), but
you can still get them to work by forcing the device descriptor to what
the drive _really_ wants to work with.
     An RLL drive would probably be the old 2 cable XT style, wouldn't it?
If it is, it should work with some of the older PC compatible hard drive
controllers (like the Burke&Burke; I ran a 65MB RLL drive on that for
years).
     The driver I did also had the advantage of being able to use a hard
drive that had problems on cylinder 0; you could just set the start track
of the drive to a higher #, and it would skip the bad cylinder(s)
altogether. I don't know if I would recommend this with critical data (bad
tracks, depending on the cause, may spread over time), but I did get a
Seagate 20 GB with a bad track 0 to work with it (and it wouldn't work on
a PC at all).
--
L. Curtis Boyle