Path: utzoo!utgpu!water!watmath!clyde!rutgers!orstcs!mist!johnm
From: johnm@mist.cs.orst.edu (John Matzka)
Newsgroups: comp.sys.ibm.pc
Subject: Re: F-15 Strike Eagl
Keywords: disk drive floppy
Message-ID: <2713@orstcs.CS.ORST.EDU>
Date: 17 Feb 88 16:52:12 GMT
Sender: netnews@orstcs.CS.ORST.EDU
Reply-To: johnm@mist.UUCP (John Matzka)
Organization: Oregon State Universtiy, Corvallis, Oregon
Lines: 42

In article <3255@cup.portal.com> DEIL_CLAYTON_BLAND@cup.portal.com writes:
>The index hole tells the disk controller where sector zero begins!
>All floppy disk have them!
>...
Although this little hole does serve as a reference point for SOME drives, not
all disks have them.  I just bought a large number of disks (okay 30) and none
of them have these little holes and the disks work just fine.

>Most drives have a LED and photo cell arangement to mark the start
>of sector zero.
>...
I can't say what percentage of disk drives actually use this little hole but
Apple ][ series doesn't and some IBM compatible units don't either.

Also, an interesting(?) point.  If there is only one (or none I suppose) of
these little holes in the disk media, then the disk is soft sectored.  If
there are many of them then the disk a hard sectored.  Just try using a hard
sectored floppy in a drive which expects only soft sectored disks and vice
versa.

>Deil Bland


John Matzka

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Internet: johnm@mist.CS.ORST.EDU                |  The opinions expressed here
UUCP:     {tektronix, hp-pcd}!orstcs!johnm      |  do not necessarily reflect 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~|  those of OSU, the CS dept.
Everything that is not nailed down is mine.     |  or my supervisors.
  Anything I can pry loose is not nailed down.  | 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

John Matzka

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Internet: johnm@mist.CS.ORST.EDU                |  The opinions expressed here
UUCP:     {tektronix, hp-pcd}!orstcs!johnm      |  do not necessarily reflect 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~|  those of OSU, the CS dept.
Everything that is not nailed down is mine.     |  or my supervisors.
  Anything I can pry loose is not nailed down.  | 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~