[syslinux] makebootfat: an utility to create bootable USB disks

[Andrea Mazzoleni]

On Wed, 23 Feb 2005 13:12:04 -0800, H. Peter Anvin <hpa at zytor.com> wrote:
> What I meant is the annoying fact that there isn't an easy way to query
> the geometry the BIOS is using for a floppy disk; there is a query call
> but it returns the "capabilities of the device", not the actual one in use.
Ok. But for an USB device, the capabilities of the reader are also the
capabilities of the media because they are the same thing.

Also, the USB-Mass Storage specification uses linear addressing to specify the 
sector number, so the only requirement for the BIOS is to use the same 
geometry in the int 13/08 and in the linear addressing computation for
int 13/02. Which appears to me the most reasonable approach. The
effective geometry used doesn't matter, supposing that the number of
cylinders is not limited.

> USB-FDD may very well assume a floppy-sized device, and could at least
> theoretically be limited to 1.44 MB.
Yes. If a BIOS imposes a such limit, it cannot work.

-- 
Andrea Mazzoleni
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