IBM drives in a Kaypro

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Thu Feb 13 16:51:31 2003

> On Wed, 12 Feb 2003, Tony Duell wrote:
> > According to the O&A TechRef, there are 2 distinct 40 cylinder drives :
> > The 'Slimline' drive used in the PortablePC and PCjr. This des not have
> > the asterisk
>
> Originally a Qume "Qumetrak 142"?

Certainly a Qume something-or-other.
[...]

> matter, I failed to include step rate. The Qume drive was arguably the
> first "half height" 5.25" drive, and it was SO slow that changes needed to
> be made in the OS to keep from timing out waiting for it to seek.
> Some say that it was the worst drive ever sold; I don't agree - I had some
> BASF 2/3 height drives that were worse.

Having seen those darn things in RML 380Z machines, I fully agree with
you. Horrible drives..

>
>
> > The double density (360K) drive for the PC/AT. This does have the asterisk.
> > They are difference electrically (made by difference companies?). I think
> > the use of pin 34 on the connector differs too.
>
> At about the time that the 1.2M was released, there was a change in the
> use of pin 34. One use was "READY"? the other was "DISK CHANGED"?

Yep. Originally READY, became Disk Change on the 1.2M and therefore the
360K unit that went with it...

-tony
Received on Thu Feb 13 2003 - 16:51:31 GMT