AT interface under xenix/386 2.3.2

[Wm E Davidsen Jr]

In article <1990Jan9.234525.12280 at metro.ucc.su.oz.au> glenn at extro.ucc.su.oz.au (G Geers) writes:

| After looking through this I came across two drives which appear to be quite
| good. They are:
| 1. ST4144R  122.7Mb formatted, ST412 interface (<- supplants ST506 ??)
| 2. ST1144A  125.8Mb formatted, AT interface

| Looking through the Xenix release notes I am led to believe that the ST4144R
| will run under Xenix. What controller do people recommend ? It is an RLL drive
| but I don't think that matters.

  Only in that you want an RLL controller. I suggest the WD1006VSR2,
since the track buffering is in hardware, and it is much faster with
Xenix than Adaptec (at least in my systems).
| 
| The ST1144A is a 3.5" drive with a maximum(!) seek time of 20ms which is quite
| quick. The problem is that the AT interface is not mentioned anywhere in the
| Xenix docs. Has anyone used this drive (I'm guessing it's been released in
| the US or Europe, we're always a little behind.) ? Does anyone know how an
| AT interface differs from the standard ST412 ? Will Xenix support an AT
| interface.

  This is certainly not common yet, and unless you get an answer from
SCO I would consider it a chance to be at the bleeding (uh, that's
cutting) edge of peripherals.

  To make it worse, some ads say AT interface and means ST412, some mean
the interface Seagate is pushing. Conner is also delivering a small,
fast, 204MB (as I recall) drive with builtin controller, which they call
IDE. One distributor says that's the same as Seagate's AT interface,
another says it's not.

  If you try this out, please post. One real question is if you can run
multiple drives with Xenix. If you don't have a controller does each
drive take a slot for the bus interface board? One distributor said
"one bus unit for all drives," one said "one bus unit per drive," one
said "you can only run one drive, but they're so big you'll never need
another," and one said "unix? Sure these work with any DOS
application!"

  I have no trouble getting answers to these questions, just in getting
the same answer from more than one supplier, or any useful answer from
anyone.
-- 
bill davidsen	(davidsen at crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen)
"The world is filled with fools. They blindly follow their so-called
'reason' in the face of the church and common sense. Any fool can see
that the world is flat!" - anon