Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!cornell!uw-beaver!tektronix!uunet!dalcs!iisat!kevin
From: kevin@iisat.UUCP (Kevin Davies)
Newsgroups: comp.sys.ibm.pc
Subject: Re: More ? re Formatting and writing 360K diskettes with 1.2M drive.
Summary: 1.2Meg vs 360K
Message-ID: <110@iisat.UUCP>
Date: 11 Aug 88 23:30:00 GMT
References: <11069@cgl.ucsf.EDU> <2977@nicmad.UUCP> <6239@chinet.chi.il.us> <2972@dalcs.UUCP>
Distribution: na
Organization: International Information Service, Dart., NS
Lines: 32

In article <2972@dalcs.UUCP>, lane@dalcs.UUCP (John Wright/Dr. Pat Lane) writes:
> While we're on the subject (again), I've been wondering if, when I reformat
> a 360K disk using FORMAT A:/4 (actually that's a 354K disk!) in a 1.2M drive
> and the disk has been previously formatted and/or written on by a regular
> low density drive, am I not leaving part of the wider low density track on
> the disk and might I not have trouble reading the information written by the
> 1.2M drive on a low density drive?  Does this not imply that once a disk has
> *written* on by a low density drive, it has been "soiled" and probably should
> not be re-formatted and used on a 1.2M drive, not at least, if the disk is to 
> be readable by both types of drives?  I assume, of course, that when I format 
> on a low density drive, I completely erase any 1.2M information and the disk
> is the same as if it had never been written on.
> 

What you've said above is correct, especially about a disk that has been
formatted under 360K format and then later on a high density drive.
In order to use a disk that has previously been formatted and used on a
360K drive, you have to remove *everything* to make it appear like a
new disk that has not been touched.  I don't think one of those Bulk
Erase programs will work that great since you are relying on the head
technology again (reguire the larger head of the 360K).
I've used these magnetic bulk erasers and normal magnets to erase a disk
and they work perfectly, but you *must* keep it away from important
disks !

By keeping these ideosyncrises in mind, you should not have any problems
moving a disk between the 2 drive types.

-- 
Kevin Davies		International Information Service (IIS)
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Bitnet/Uucp: kevin@iisat.uucp	 Arpanet: kevin%iisat.uucp@uunet.uu.net