Date   : Sun, 12 Feb 2006 21:12:29 +0000
From   : Andrew Benham <adsb@...>
Subject: Re: Reading and writing BBC DFS disks under Linux

Stephen Hippisley-Cox wrote:

> I'm having trouble trying to access BBC DFS 3.5in floppies under Linux.
>  The Omniflop website hints that it should be fairly easy to do, but I'm
> afraid I'm stuck.
> Anyone have any ideas? Is it a matter of finding the right parameters
> for setfdprm?

I've had success today reading ADFS disks on Linux, using LibDsk
(http://www.seasip.demon.co.uk/Unix/LibDsk/).

"dsktrans /dev/fd0 foo.raw -otype raw -format acorn640 -logical"

has given me a 640k ADFS image file which looks right.


Doing DFS requires that the hardware supports single-density.

LibDsk looks to support DFS (disk types 'bbc100     : BBC 100k'
and 'bbc200     : BBC 200k').

I know early PCs which used a genuine floppy disk controller IC
tended to have the "density select" pin on the IC hard-wired
to the "double density" position.

-- 
Andrew Benham         adsb@...       
Southgate, London N14, United Kingdom

The gates in my computer are AND OR and NOT, not "Bill"