Xenix, Unix, and IDE drive install problems.

[Dick Dunn]

tom at tandon.UUCP (Tom Friel) writes:
> Sorry this is so long, but I would like to know if users of IDE drives
> have experienced problems with SCO Xenix 2.3.2 and Interactive Unix 2.2.

I've been running a pair of IDE drives on a machine with ISC 2.2 for a while
now.  I've occasionally pounded on them pretty hard, and I've see no
failures.  The drives are Maxtor (MiniScribe) 7080-A.

>...I will be nice and not mention drive manufacturers...

Tom - I don't think this is being "nice."  The drive manufacturers need to
know if there's a problem with their drives, and people on the net want
to know if there is some particular device, or combination of device(s) and
software, that won't work.  That's what the net is here for!

>...I'm posting because,
> until recently, I had heard of no such field problems with IDE drives and
> had posted a note saying everything was hunky-dory...

I don't see any reason to worry about IDE _per_se_.  It's just a drive
interface, and *if it's implemented correctly* it looks and works just like
a standard AT disk controller.  The description later in Tom's article...
	...a timing problem whilst selecting and testing
	the presence of a drive...
	...the busy bit in the status register will go
	low before IRQ 14 has been asserted...
...says that it's a real hardware problem, and we need to know what
hardware has the problem.  Even if it's only been found in one particular
manufacturer's drive so far, that drive might be using a piece of VLSI
that's also used in other controllers.  (Who knows; it sounds like a bus-
interface logic problem...which means [pure speculation here!] that it
could conceivably show up in any sort of device--not just an IDE drive; in
fact, not just a disk drive.)

Details, please?
-- 
Dick Dunn     rcd at ico.isc.com -or- ico!rcd       Boulder, CO   (303)449-2870
   ...Worst-case analysis must never begin with "No one would ever want..."