From: "Jaroslav Lukesh" <lukesh@seznam.cz>
Date: Thu, 18 Nov 1999 11:39:14 +0100


Jak na formátovat větší disketu
----------------------------------

	Can I used 'extra' formatted floppies, like 1.74MB or 2m 1.88MB ? 

	Yes. Normal higher formats as well as some 2m formats will work. 

0. mknod /dev/fd0u1722 b 2 60
1. fdformat /dev/fd0u1722 
2. mkdosfs /dev/fd0u1722 
	ted by se dala dat data z pripadneho image:
	dd if=1743-eth_PPP_QOS.floppy of=/dev/fd0u1743
3. syslinux -s /dev/fd0u1722 (the -s is very important here.) 
	(syslinux je k nalezeni na CD RH5.2 v
/mnt/cdrom/misc/src/trees/syslinux-140/
	zkopirovat vse do /root/syslinux/
	na soubor syslinux (13016 bytes) dat atribut eXecute,
	pak jej spustit viz vyse)

A problem with these disks is there is no way to accuratly determine their
size. 
For LRP to be able to mount these disks, you must specify the correct size,

IE fd0u1680, fd0u1840, etc. Apparently these disks break sooner as well 
(read errors etc), though I haven't heard of someone who had this problem 
4more frequent then with regular disks (anyone) 

> How to create a 1.7MB floppy in DOS? I have a dificulty to
> make a floppy
> using superformat. Because is hard for me to compile and install
> superformat package. Is there any easy way to create it?

I had difficulty getting superformat on my SUSE machine.  I suppose this is
because
the following alternative formatting sequence works, so the SUSE developers
didn't
think it warranted inclusion (?):

 (if needed: mknod /dev/fd0u1680 b 2 44)
 fdformat /dev/fd0u1680
 mformat -t 80 -h 2 -s 21 a:
 mbadblocks a:
 syslinux -s /dev/fd0u1680

mformat/mbadblocks are not present on LRP, so this cannot be used unless
you
have
another Linux machine around (if I can find the time, I will build an lrp
with them).

The cylinder/head/sector vs. /dev notations are unfortunately not obvious
to
the
occasional user (me), so I looked up some common combinations:

 device            major  minor   -t (cyl)   -h (heads)  -s (sectors)
 /dev/fd0u1440     2       28     80         2           18
 /dev/fd0u1600     2      124     80         2           20
 /dev/fd0u1680     2       44     80         2           21
 /dev/fd0u1722     2       60     82         2           21
 /dev/fd0u1743     2       76     83         2           21
 /dev/fd0u1760     2       96     80         2           22
 /dev/fd0u1840     2      116     80         2           23
 /dev/fd0u1940     2      100     80         2           24

t*h*s/2 = diskette size in megabytes.

1.68M should always work, but YMMV on larger sizes due to variation in
drive and diskette characteristics.

As for superformatting in DOS, I don't have much experience with it.
http://www.simtel.net has some DOS superformatting utilities (from docs:
mform19.zip only appears to handle 1.6M, fdform18.zip seems to have more
options but may be superceded by 2m30.zip).  Mform has a Win9x version
(http://www.herne.com/mdisk1.htm) that I have used to create 1.6M floppies
for LRP.

###############################################################

popis vsech ruznych formatu je v info dokumentaci k fdformatu
(info fdformat), kterym lze takovou disketu vytvorit
cisla potrebna pro makenod se daji najit v nekde
dokumentaci kernelu (adresar Documentation ve zdrojacich jadra)