Date: Thu, 21 Mar 1996 17:49:06 -0700 (MST) From: Terry Lambert <terry@lambert.org> To: joerg_wunsch@uriah.heep.sax.de Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: Adding a damn 2nd disk Message-ID: <199603220049.RAA01342@phaeton.artisoft.com> In-Reply-To: <199603212347.AAA14666@uriah.heep.sax.de> from "J Wunsch" at Mar 22, 96 00:47:40 am
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> > The driver for old MFM drives should read the CMOS drive table. > > No such thing like a CMOS drive table. CMOS holds the drive type, but > the BIOS holds the drive table. Each BIOS has got a very own idea of > what a particular CMOS drive type might mean. CMOS drive table index, then. I remember that some BIOS' reserved CMOS space for two slots (44? 45?) to let you specify the information. AMI was one of them... In any case, a linear congruential search for the boundry conditions followed by a binary search could easily find the last sector on any device for you. This is what is done in a partition recognition TSD under Win95. In any case, it's possible to put the data there so that when the tool program issues the ioctl, the data is returned. Worst case, you use the BIOS table (or CMOS entries for the last two BIOS drive types), and you let the user override it in their config file (or better yet, via booting -v). Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.
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