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From: enzerinkp@topaz.ucq.edu.au (Hello, hello. What's going on here then?)
Newsgroups: comp.sys.ibm.pc.hardware,comp.sys.ibm.pc.misc
Subject: Re: make 720K floppy a 1.44M
Message-ID: <1991May9.185346.7148@topaz.ucq.edu.au>
Date: 10 May 91 01:06:34 GMT
References: <1991May7.185223.27362@maverick.ksu.ksu.edu>
Organization: University College of Central Queensland, Australia
Lines: 27

In article <1991May7.185223.27362@maverick.ksu.ksu.edu>, devolder@festus.ksu.ksu.edu (Eric DeVolder) writes:
> Okay, all you IBM PC techno gurus, here is a question for you.  What I have
> in mind is this:  Is it possible to create your own device driver, for DOS
> or some other OS, that does not use the BIOS but rather communicates directly
> with the drive controller and make the drive believe that it is a 1.44M disk?

I assume you are then going to use 1.44mb disks rather than opting for the
dangerous practice of punching a hole in a 720k disk.

I suppose it depends on the drive itself. One of the differences between high
and low density drives is the accuracy with which the mechanism operates. If
you are making a low density drive you obviously do not need as much precision
in your movement and writing as with a high density.

The answer then comes down to the quality of the drive. As an aside a device
driver which allows larger than normal capacity on a variety of disks is a
bios modifier called FDREAD. Its overhead is about 128 bytes and it can give
you some whopping increases in capacity. Most larger capacities are of course
only readable when using the driver. Still...

-- 
                 "Hello, Hello. What's going on here then?"
^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v
Peter Enzerink          3rd year Student, Bachelor Applied Science (Computing) 
                                              University of Central Queensland
Internet: ENZERINKP@TOPAZ.UCQ.EDU.AU                          Rockhampton 4702
       or ENZERINP@JASPER.UCQ.EDU.AU                                 Australia