From owner-freebsd-hackers Wed May 3 10:42:41 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id KAA06755 for hackers-outgoing; Wed, 3 May 1995 10:42:41 -0700 Received: from duality.gnu.ai.mit.edu (!#$%^&*!#$%^&*!#$%^&*!#$%^&*!#$%^&*!#$%^&*!#$%^&*!#$%^&*!#$%^&*!#$@duality.gnu.ai.mit.edu [18.43.0.236]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id KAA06749 ; Wed, 3 May 1995 10:42:39 -0700 Received: by duality.gnu.ai.mit.edu (8.6.12/8.6.12GNU) id NAA09007; Wed, 3 May 1995 13:42:32 -0400 Date: Wed, 3 May 1995 13:42:32 -0400 Message-Id: <199505031742.NAA09007@duality.gnu.ai.mit.edu> From: "Charles M. Hannum" To: phk@ref.tfs.com CC: dyson@Root.COM, sos@FreeBSD.org, paul@isl.cf.ac.uk, terry@cs.weber.edu, hackers@FreeBSD.org In-reply-to: <199505031557.IAA12888@ref.tfs.com> (message from Poul-Henning Kamp on Wed, 3 May 1995 08:57:15 -0700 (PDT)) Subject: Re: NetBSD supports LBA and large (EIDE) drives Sender: hackers-owner@FreeBSD.org Precedence: bulk According to Hale Landis, the guy who wrote 20-40% of the ATA std, LBA is inmature and buggy, even more so considering that it is not needed for anything. The problems that Hale has noted are entirely on the software end -- that there is little or no standardization about how the BIOS converts beetween C/H/S addresses and LBAs. This is only an issue when sharing a disk with another OS, or when booting from it, and is analagous to the standard geometry translation compatibility problems. LBA mode is not `needed' for IDE drives smaller than 8GB. However: 1) In practice, the differences between BIOS LBA implementations seem to be less annoying than the differences between BIOS C/H/S implementations. 2) There are already 9GB SCSI drives on the market, and the antiquated C/H/S addressing is not capable of supporting a drive that large. 3) LBA mode is *required* for ATAPI devices (i.e. EIDE CD-ROMs). What I really don't understand is why people are flaming at me about this.