Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!cs.utexas.edu!husc6!m2c!wpi!dseah
From: dseah@wpi.wpi.edu (David I Seah)
Newsgroups: comp.sys.apple
Subject: Re: Speaking of Quality Computers
Message-ID: <3017@wpi.wpi.edu>
Date: 27 Jun 89 21:23:13 GMT
References: <8906250736.AA14091@crash.cts.com>
Reply-To: dseah@wpi.wpi.edu (David I Seah)
Organization: Worcester Polytechnic Institute, Worcester, MA. USA
Lines: 34

In article <8906250736.AA14091@crash.cts.com> pnet01!pro-sol!pro-charlotte!pro-novapple!daveharv@nosc.mil writes:
>Network Comment: to #7480 by obsolete!pro-angmar!pro-generic!ulf
>
>The drive they sell, if I remember correctly, is just a drive with two heads
>on it.  You don't have to turn the disk over to access the other side.  That's
>all there is to it.  It's not made so that you can access one contigious block
>of data.  It just saves you the hassel of removing the diskette, turning it
>over and reinserting.

Somethings fishy.  Assume that you are using a disk that you normally flip
over to work with the other side (something like AppleWorks on 5.25").
Isn't that second side going to have the datastream recorded in the opposite
direction relative to the first side?

SIDE ONE 	[head]
data direction	------>    
				Apple II style, flippy disk
data direction  <------
SIDE TWO

SIDE ONE	[head]
data direction  ------>
				IBM-PC style, double sided disk.
data direction  ------>
SIDE TWO	[head]

It would seem for this drive to work, it would have to reverse the disk
direction everytime it flipped sides, or somehow be able to decode Apple's
disk format backwards.  It probably is just like the IBM style drive with a
ProDOS driver.

Dave Seah | O M N I D Y N E  S Y S T E M S - M |   Internet: dseah@wpi.wpi.edu 
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