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From: hah@isum.intel.com (Hans Hansen)
Newsgroups: comp.sys.amiga
Subject: Re: An Amusing Anectode (The tale of the 2 Meg disk)
Message-ID: <873@omepd>
Date: Sun, 12-Jul-87 11:13:21 EDT
Article-I.D.: omepd.873
Posted: Sun Jul 12 11:13:21 1987
Date-Received: Mon, 13-Jul-87 04:20:13 EDT
References: <398@rocky.STANFORD.EDU> <1649@cadovax.UUCP>
Sender: news@omepd
Reply-To: hah@isum.UUCP (Hans Hansen)
Distribution: world
Organization: Intel Corp., Hillsboro
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In article <1649@cadovax.UUCP> keithd@cadovax.UUCP (Keith Doyle) writes:
>In article <398@rocky.STANFORD.EDU> ali@rocky.stanford.edu (Ali Ozer) writes:
>>Anyway, now I have a 2.0 Meg capacity floppy disk. 8-)
>
>Well, if 2.0M 3.5" floppys achieve their high density in the same way
>HD 5.25" floppys do, you might not want to use it.  HD disk drives use
>a higher write current, because the floppy media is less sensitive, which
>for some reason permits higher density.  Normal disk drives will not
>put out a high enough write current to write the media reliably.  I
>remember having all kinds of problems trying to format HD disks on
>non-HD drives until this was explained to me, and I gave up trying.
>
The new HI-Density Disks use PERPENDICULAR rather than PARALLEL magnetic
particle alignment.  The 2Meg floppy doubles the track count or has 160
cylendars.  Upgrading the A1000 with a 2Meg drive while sounding neet
and deliver more bytes for the buck, unless commodore gets on the band
wagon (HINT HINT), will cause a compatibility nightmare.  What I would
like to see is a driver that can recognise both types of drives and
automatically adjust the cylendar count.

Hans