Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!zaphod.mps.ohio-state.edu!samsung!munnari.oz.au!bruce!cechew
From: cechew@bruce.cs.monash.OZ.AU (Earl Chew)
Newsgroups: comp.os.minix
Subject: Re: Shoelace, Boot sector, Partition sector
Message-ID: <3301@bruce.cs.monash.OZ.AU>
Date: 1 Nov 90 21:45:28 GMT
References: <35159@nigel.ee.udel.edu>
Organization: Monash Uni. Computer Science, Australia
Lines: 46

In <35159@nigel.ee.udel.edu> TEMARI%ECAMV1.dnet.ge.com@vm1.nodak.edu writes:

>that Gordon W. Ross (gwr@linus.mitre.org) must be incorrect.  So I would
>then think that the partition boot sector passes:
>          DL = drive to read boot sector from
>       DS:SI = pointer to partition table entry to boot

>(I never believe documentation, the only true documentation is
> the program itself.)

This is getting confusing.

1. Currently winiboot passes:
          DL = drive to read boot sector from
       ES:SI = pointer to partition table entry to boot

2. Gordon W. Ross says that the Microsoft documentation says:
       DS:SI = pointer to partition table entry to boot

3. Michael Temari says that the Zenith 3.3+ systems uses:
          DL = drive to read boot sector from
       DS:SI = pointer to partition table entry to boot

(1) is known to boot at least two versions of MSDOS (my old machine and my
current machine).

(3) boots Michael Temari's Zenith 3.3+ system. Michael, when you disassembled
the bootstrap did you see whether DS:SI or ES:SI is used? Your posting didn't
make it at all clear.

I don't know if (2) will boot anything.

I think that to remain compatible with the world, the following will be
required:

1. DL contains the drive code
2. DS:SI pointer to partition table entry to boot
3. ES:SI pointer to partition table entry to boot
4. Partition table entry to boot has the drive code entered into its active
   field

Earl
-- 
Earl Chew, Dept of Computer Science, Monash University, Australia 3168
EMAIL: cechew@bruce.cs.monash.edu.au PHONE: 03 5655447 FAX: 03 5655146
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