From: Jason Green <news AT jgreen4 DOT fsnet DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: 18-sector limit with biosdisk()
Date: Wed, 14 Feb 2001 23:47:52 +0000
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To: djgpp AT delorie DOT com
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NoEmailAds AT execpc DOT com (Chris Giese) wrote:

> I have experimenting with boot sectors lately, and I wonder if
> it's REALLY the BIOS that makes oversized floppies fail. Maybe a
> bootloader fails to patch the maximum sectors-per-track value in
> the floppy parameter table (FPT). Or maybe it makes a bad guess
> or assumption about the floppy geometry.
> 
> Last time I checked, the built-in loader of Linux (bootsect.S) patches
> the FPT, but does NOT support 21 sectors per track. I downloaded Tom's
> boot/root disk, and it worked OK. His disk has 21 sectors per track,
> 82 tracks, and boots with LILO.

Precisely - LILO will load the kernel from an oversize floppy, but the
kernel will not boot itself from the same media formatted in the exact
same way.  

If the Linux source shows that oversized floppies are not handled
properly then we can safely say that the BIOS is not the culprit.