From owner-freebsd-questions Sun Jul 28 15:44:12 1996 Return-Path: owner-questions Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id PAA15219 for questions-outgoing; Sun, 28 Jul 1996 15:44:12 -0700 (PDT) Received: from relay-2.mail.demon.net (disperse.demon.co.uk [158.152.1.77]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id PAA15212 for ; Sun, 28 Jul 1996 15:44:10 -0700 (PDT) Received: from post.demon.co.uk ([158.152.1.72]) by relay-2.mail.demon.net id ac05890; 28 Jul 96 23:44 +0100 Received: from jraynard.demon.co.uk ([158.152.42.77]) by relay-3.mail.demon.net id aa27305; 28 Jul 96 23:42 +0100 Received: (from fqueries@localhost) by jraynard.demon.co.uk (8.7.5/8.6.12) id TAA02655; Sun, 28 Jul 1996 19:28:05 GMT From: James Raynard Message-Id: <199607281928.TAA02655@jraynard.demon.co.uk> Subject: Re: Update on 'partition sector garbled ...' To: Robert Eckardt Date: Sun, 28 Jul 1996 19:28:04 +0000 () Cc: questions@freebsd.org In-Reply-To: <199607280816.KAA08014@ghost.mep.ruhr-uni-bochum.de> from "Robert Eckardt" at Jul 28, 96 10:16:28 am X-Mailer: ELM [version 2.4 PL24 ME8a] Content-Type: text Sender: owner-questions@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > > This time however, I went into depth and found that the wd driver > reports the wrong number of cylinders. > My AT-Bus disk (Conner 544CP) has 1054 cylinders, but FreeBSD sees > only 1053. It is partitioned as: [snip] > Any idea why FreeBSD sees only 1053 cyls. or how to work around ? > Anything special about the Conner ? Interesting. I have the same problem with a Conner CFA420, except the discrepancy is a litle larger - FreeBSD sees only 665 cylinders instead of 826. Every other OS I've run (DOS, Win3.1, WinNT, OS/2, Linux) on it has managed to work this out without any problems, as do the BIOSes on both the PC's I've used it in, so I think there must be something strange about how FreeBSD handles Conner disks (or alternatively, something strange about how Conner disks respond to being probed by FreeBSD). If there are any assembler wizards out there, the relevant code is in /sys/i386/boot/biosboot/bios.S (I'll have a look at it myself, but my reference manual is 400 miles away :-() 'info as' will get you the documentation on AT&T syntax (note that 'mov' is the opposite way round from Intel syntax, among other oddities; also, don't forget that you can't call DOS functions under FreeBSD :-)