[syslinux] Trouble with Superfloppy format

[Gene Cumm]

On Wed, Nov 17, 2010 at 12:31, Sven Geggus <lists at fuchsschwanzdomain.de> wrote:
> Gene Cumm <gene.cumm at gmail.com> wrote:
>
>> I doubt that it'll ever work reliably as a "Superfloppy" if it doesn't
>> fit inside what appears to be the old limits on a floppy (256,255,63).
>
> Well it _does_ work fine one one Machine but does not on another.

Thanks for finally providing detailed information on the failing machine.

Also, the fdisk output is nearly irrelevant in this context (except
for its total capacity) as that's just how your Linux kernel wants to
interpret it and your BIOS may take a totally different spin on its
geometry.

> Non Superfloppy mode is not an option because the target device (not the one
> I'm currently testing but same problem) an encrypted USB Flash drive
> (http://www.takeanyware.com/Products/ClassifiedSecureFlashDrive/tabid/91/Default.aspx)
> does not "like" to get partitioned.

I was wondering why and that explains it well.  Ouch, sorry to hear
the bad news.

>> Another idea is to change from H/S 64/32 to 255/63 then redo the
>> partitioning (3948+ Cylinders; best to use whole cylinders for
>> partitions for compatibility).  Total capacity is 121 * 2 ^ 28.  Based
>> on the total capacity, H/S 64/32 is the best way to maximize usable
>> capacity.
>
> Which way would I be able to do "partitioning" when I did not use anything
> like fdisk at all?
>
> All I did is "mkdosfs -I /dev/sdb".

Seeing as partitioning is not an option, you should provide a
[block-count] (see man mkdosfs for more details).  I'd suggest a limit
along the lines of what I've already mentioned.  This may prove more
compatible.  If that still doesn't work with a block count of 257,040
or 130,560 (yes, VERY small) or even the extremely small count of 2880
or 5760 (standard floppy sizes; 1440kiB and 2880kiB respectively),
change to a much smaller UFD (like ~1 GB or less) and try again as
your BIOS probably hates the UFD.

-- 
-Gene