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Date: Sun, 3 Aug 1997 12:25:31 -0700 (PDT)
From: Doug White <dwhite@gdi.uoregon.edu>
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Reply-To: Doug White <dwhite@resnet.uoregon.edu>
To: Hugh Blandford <hugh@island.net.au>
cc: questions@FreeBSD.ORG
Subject: Re: Creating a specific floppy device
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On Fri, 1 Aug 1997, Hugh Blandford wrote:

> I am working with software that comes on a diskette with a format that
> under SCO is accessed by the device /dev/rfd0135ds18, ie r (raw,
> unbuffered) fd0 (floppy drive 0) 135 (135 tracks per inch) ds (double
> sided) 18 (18 sectors per track).

Isn't this a 720KB floppy?  :-)

> Being newish to unix can someone please tell me how to create a floppy
> device that meets these specifications under FreeBSD 2.2.2.

You'll have to look at the fd source in the kernel.  We provide a lot of
non-standard sizes already:  

gdi,ttyp3,~,65>ls /dev/rfd*
/dev/rfd0       /dev/rfd0.800   /dev/rfd0f      /dev/rfd1.1720  /dev/rfd1c
/dev/rfd0.1200  /dev/rfd0.820   /dev/rfd0g      /dev/rfd1.360   /dev/rfd1d
/dev/rfd0.1440  /dev/rfd0a      /dev/rfd0h      /dev/rfd1.720   /dev/rfd1e
/dev/rfd0.1480  /dev/rfd0b      /dev/rfd1       /dev/rfd1.800   /dev/rfd1f
/dev/rfd0.1720  /dev/rfd0c      /dev/rfd1.1200  /dev/rfd1.820   /dev/rfd1g
/dev/rfd0.360   /dev/rfd0d      /dev/rfd1.1440  /dev/rfd1a      /dev/rfd1h
/dev/rfd0.720   /dev/rfd0e      /dev/rfd1.1480  /dev/rfd1b

The number after the . is the size of the disk. You'll have to look at the
source to see what they map to in terms of actual disk geometry.

Doug White                              | University of Oregon  
Internet:  dwhite@resnet.uoregon.edu    | Residence Networking Assistant
http://gladstone.uoregon.edu/~dwhite    | Computer Science Major
Spam routed to /dev/null by Procmail    | Death to Cyberpromo