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From: jimvons@ashtate (Jim von Schmacht)
Newsgroups: comp.sys.mac
Subject: Re: Beware formating HD floppies in DSDD drives
Message-ID: <839@ashton.UUCP>
Date: 9 Mar 90 16:33:52 GMT
References: <1567@diamond2.UUCP>
Reply-To: jimvons@ashton.UUCP (Jim von Schmacht)
Distribution: comp
Organization: Ashton-Tate, Torrance, CA
Lines: 21

In article <1567@diamond2.UUCP> derosa@cell.mot.COM (John DeRosa) writes:
>Apple (are you listening?) this is silly engineering
>in my book, not bad, just silly.

The tracking on a formatted 1.44 is *Much* tighter than that used on the
800k, leaving some space between tracks when formatted as 800k in an older
drive.  When the HD floppies are tested, they are given a test format which
is NOT completely overwritten by the old mechanisms.  When a new drive which
can read ALL the space available on the disk, it sees both good 800k and 
the garbage between tracks.  In my book, one can't go back in time to tell
the original SONY (note manufacturer/DESIGNER) team and tell them to use
techniques which did not then exist.  Bitch to SONY, as they are the ones
who defined the standard, with Apples input being the ability to be variable
as opposed to constant speed (the reason why PS/2's only get 720k while we
get 800k, and the Amiga 880k)

-- 
Jim von Schmacht    Senior Member, Project Test Staff    Ashton Tate Corporation
Disclaimer: Standard Issue
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                 "It isn't the years - it's the mileage" -Indiana Jones