Path: utzoo!attcan!uunet!samsung!zaphod.mps.ohio-state.edu!wuarchive!udel!mmdf
From: TEMARI%ECAMV1.dnet.ge.com@vm1.nodak.edu
Newsgroups: comp.os.minix
Subject: Shoelace, Boot sector, Partition sector
Message-ID: <34243@nigel.ee.udel.edu>
Date: 22 Oct 90 23:33:38 GMT
Sender: mmdf@ee.udel.edu
Lines: 35

Hello Net:

I was installing shoelace and everything worked fine when I booted my
Minix partition, but when I tried to boot my DOS partition I got the
message: Unformatted partition.  So I disassembled the DOS boot sector
to find out what would cause the Unformatted partition message.  It would
do this if when comparing the starting sector and total sectors from the
partition table entry with the data in the start of the DOS boot sector.
If the numbers didn't match you get the Unformatted partition message.
So I figured that winiboot wasn't passing the partition entry correctly,
but I though I would have seen some bug fixes from the Net.  To make a
long story short :-) according to bootlace what is passed to a boot sector
is the drive in register dl and a pointer to the partition table entry in
ES:SI.  Here is the first few instructions from my Zenith DOS 3.3+ boot
sector:
	mov	bx,0x07c0
	cli
	mov	ss,bx
	mov	sp,0x0263
	sti
	push	ds
	pop	es		<-------- the kicker
	mov	ds,bx
it then went on to do the comparison with the partition entry with ES:SI.

According to this code it expects that the partition entry be passed to it
in DS:SI not ES:SI.  What is actually correct???  My own homebrew version
of the partition selection at boot up time has ES and DS the same when the
boot sector is loaded and run.

What is the official parameters passed to the boot sector??????



Michael Temari                                  temari@ecamv1.dnet.ge.com