[comp.sys.ibm.pc.hardware] AT 3 1/2" Floppy question

brada@bardlover.Eng.Sun.COM (Brad Albom) (03/13/91)

This is probably a simple question, but I just installed
a 3 1/2" floppy drive in my AT (sorry, don't remember brand
of floppy or controller). It works fine, but it seems that
whatever density disk it reads the first time after boot,
(1.44Meg or 720Meg) is the only type it will recognize 
until I re-boot. That is, if I first read from a 1.44Meg floppy,
there is no problem until I put a 720K floppy in. At that
point I get the typical, error reading from floppy message.
Subsequent read of the 1.44Meg variety still work.

Is this considered normal operation ?

-brad albom
Software Engineering Solutions, Inc
Office: (707) 552-5248    - Probably get our machine
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email : brada@eng.sun.com - Best Bet (Tuesday-Friday)

mir@opera.chorus.fr (Adam Mirowski) (03/13/91)

In article <9678@exodus.Eng.Sun.COM>, brada@bardlover.Eng.Sun.COM (Brad Albom) writes:
%% This is probably a simple question, but I just installed
%% a 3 1/2" floppy drive in my AT (sorry, don't remember brand
%% of floppy or controller). It works fine, but it seems that
%% whatever density disk it reads the first time after boot,
%% (1.44Meg or 720Meg) is the only type it will recognize 
%% until I re-boot. That is, if I first read from a 1.44Meg floppy,
%% there is no problem until I put a 720K floppy in. At that
%% point I get the typical, error reading from floppy message.
%% Subsequent read of the 1.44Meg variety still work.

I had this problem when installing a 5.25" drive in my previous computer,
some years ago. The reason was that my drive wasn't configured to signal
a disk change to the computer. I changed the position of a switch on the
drive to DC (Diskette change) and it worked fine.
Later I learned that if you press Ctrl-C or maybe Ctrl-Break at the prompt,
DOS will reread the diskette as if I received a disk change signal.

Of course, it was a 5.25" drive, not a 3.5" one.
-- 
Adam Mirowski,  mir@chorus.fr (FRANCE),  tel. +33 (1) 30-64-82-00 or 74
Chorus systemes, 6, av.Gustave Eiffel, 78182 Saint-Quentin-en-Yvelines CEDEX