Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!uwm.edu!bionet!agate!web-1c.berkeley.edu!c60b-1eq
From: c60b-1eq@web-1c.berkeley.edu (Noam Mendelson)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: How do I add a 3.5" 1.44M drive to my old XT?
Message-ID: <1991Apr4.061613.537@agate.berkeley.edu>
Date: 4 Apr 91 06:16:13 GMT
References: <126.27FA60A4@buscard.FIDONET.ORG>
Sender: usenet@agate.berkeley.edu (USENET Administrator)
Organization: University of California, Berkeley
Lines: 31

In article <126.27FA60A4@buscard.FIDONET.ORG> Kevin.Gmyrek@p5.f121.n324.z1.FIDONET.ORG (Kevin Gmyrek) writes:
>
> > In article <12206@pasteur.Berkeley.EDU>
> > sadoyama@argon.berkeley.edu (Eric Sadoyama) writes:
> > >I've got an old Leading Edge Model D (an XT-compatible) that I'd like
> > >to add a 3.5" 1.44M drive to, either internally or externally.  I've
> > >been told that for various reasons, I can't do this.  Why?
> > >Is it the 8088 chip itself?  Is it the (Phoenix) BIOS?  Is it the floppy
> > >disk controller?  Or it it something that I haven't mentioned?  What do I
> > >need to upgrade in order to get this to work?
> > I assume you have the XT's original floppy disk controller.
> > You'll need a new one which recognizes 1.44Mb drives.  Also, if
> > you're going for internal, make sure you have a spare power supply
> > lead and, of course, a free slot for the drive ;-)
>   Well, Noam,  it's not quite as easy as just that!  Let's assume 
>that Eric's got a DOS version later than 3.3 which is the first
>version that supported 1.44 Mb 3.5" floppy disks (720Kb supported
>in DOS v3.2).
>   In addition to this you also need to have an AT or PS/2 BIOS in order 
>to support high density disks.  The PC and PC/XT BIOSs only support 
>low density disks (360Kb 5.25" and 720Kb 3.5").        ^^^^^^^^^^^^
 ^^^^^^^^^^^^^^^^^

I had no problems with the installation on a blue XT.  No BIOS upgrades
were necessary to read and write 1.44M diskettes, and the system
has been working flawlessly for the past two years.

+==========================================================================+
| Noam Mendelson   ..!agate!ucbvax!web!c60b-1eq | "I haven't lost my mind, |
| c60b-1eq@web.Berkeley.EDU                     |  it's backed up on tape  |
| University of California at Berkeley          |  somewhere."             |