Date   : Tue, 14 Apr 2009 08:18:34 -0500
From   : jules.richardson99@... (Jules Richardson)
Subject: Writing BBC Disc Images on Linux

Alex Taylor wrote:
> My main PC runs Mandriva, and I had a problem whereby the floppy drive
> only showed up as /dev/fd0. I couldn't therefore send an image to
> /dev/fd0d720, for example.

That's interesting - back in the day, Linux always had devices for the 
different floppy types, and 'fd0' would just be a link to the relevant 
'typical' one for the system, rather than a device special file. I'm not sure 
when that 'went away'...

It's probably still possible to create the relevant device files with mknod if 
needed (I don't have a floppy drive on this system to check) - floppies under 
Linux always have a major device number of 2 I believe, and the following web 
page seems to list the minor numbers for the various floppy-related device 
files: http://webtools.live2support.com/linux/fdformat.php

> Referring back to something someone said earlier about USB floppy
> drives, my mentioning the PCW has just reminded me that I successfully
> used a USB floppy drive to write CP/M format disk images to 720K
> floppies. I can't remember what software or OS I used though...

Interesting - IIRC CP/M (at least the OS) often uses a 128 byte sector size 
for the boot region, even if the rest of the disk uses something else; 
'native' PC disk controllers that'll read and write 128 byte sectors seem to 
be even rarer than those that'll handle plain old 256-byte FM. Knowing what 
USB unit it was could prove useful...

(Hmm, what CP/M release was it, though? Mention of '720K floppies' implies 
3.5" media, which presumably puts it at something late in the CP/M game - 
maybe they were running a 'bastardised' CP/M which no longer used the 128 byte 
sector size at all)

cheers

Jules