Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!elroy.jpl.nasa.gov!grian!alex From: alex@grian.cps.altadena.ca.us (Alex Pournelle) Newsgroups: comp.unix.xenix.sco Subject: Re: IDE controllers Message-ID: <1990Nov27.092125.3717@grian.cps.altadena.ca.us> Date: 27 Nov 90 09:21:25 GMT References: <5744@crash.cts.com> <1990Nov21.012836.12797@bagend.uucp> <1990Nov21.093114.15468@grian.cps.altadena.ca.us> <5857@crash.cts.com> Organization: Workman & Associates Lines: 52 root@crash.cts.com (Bill Blue) writes: >In <1990Nov21.093114.15468@grian.cps.altadena.ca.us> alex@grian.cps.altadena.ca.us (Alex Pournelle) writes: >I too speak from experience. The problem with IDE drives and Xenix is >not the drive or the controller ON the drive. It is with the adapter >card that plugs into the motherboard and connects to the drive. I'll have to come down on the other side of this one, Bill. The Conner people I've talked to, the SCO people, the third-parties who've send me info on this--everyone else agrees that it's the drive, and almost the drive alone, that determine the gotchas in most systems. The adapter board's important for *some BIOSes*, no question. Don't run an IDE drive with an AMI BIOS dated before 12/15/89; AMI did a major fix of their drive-handling code. Previously, you'd have to use the "Conner Compatibility jumper" on that adapter board--in other words, set for IRQ14 buffered--to keep from getting oddball drive not ready errors. This cures that. Conner themselves, though not directly, admit that the 3104 has a problem with asserting data-ready before it really was. This may be fixed in latest release, but who can tell from firmware? At the moment, what I have is a repeatable crash. Yes, it gets worse when I switch IDE adapter boards--from the ``no name'' Taiwan to the ``brand name'' Western Digital. Yes, that's right: the WD-240 is WORSE than Joe's Taiwan Clone & Bottle Company. Both crash in 6Using good adapter boards, I have installed quite a number of Xenix >systems on IDE drives with no problems. In fact I use a Conner CP3104 >on one of my test systems day in and day out. IDE drives are >basically RLL and you can expect the same general performance and data >throughput as you would with any other quality RLL drive/controller >combination. Well, "basically RLL" is a major misnomer. You've seen my postings for long enough to know that I wouldn't use an RLL ANYTHING in a production machine--too risky. But, we all know that the embedded controllers on very advanced drives used embedded servo-tracking to `watch over' the data's viability: they do a good job of ensuring you'll get back what you put on. Using an RLL controller & drive is putting 15 pounds into a 10 pound sock, and I don't think it's reliable enough. My 2 quatloos' worth. Glad you get it working: perhaps this SLS 133 will fix me up, too. Alex -- Alex Pournelle, freelance thinker Also: Workman & Associates, Data recovery for PCs, Macs, others ...elroy!grian!alex; BIX: alex; voice: (818) 791-7979 fax: (818) 794-2297 bbs: 791-1013; 8N1 24/12/3