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From: jefft@gnh-applesauce.cts.com (Jeff Tarr Jr.)
Newsgroups: comp.sys.apple2
Subject: Dos 3.3 Question
Message-ID: <9004082354.AA20755@apple.com>
Date: 9 Apr 90 00:21:27 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
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X-Unparsable-Date: Sun Apr  8 90 at 11:29:31 (EDT)



Okay, I was dissassembling the SEEKABS routine in the DOS 3.3 code that seeks
the read/write head and it appears that DOS 3.3 has the capability of seeking
and writing to half tracks as well as full tracks. I was wondering what the
reason for this was, and does this fact slow down disk access? To read a full
track, SEEKABS must be called in a loop twice, essentially seeking a double
half track to yield a full track, which seems to be wasteful, unless The Woz
originally had plans of formatting or using half tracks and then abandoned it.
I wanted to know if anyone knew why this was done in this way.


        Jeff Tarr Jr.. Sysop of the AppleSauce BBS [212] 721-4122...

America Online:  Klorn                     UUCP:  jefft@gnh-applesauce.cts.com

 * Sent by AppleSauce at Sun,  8 Apr 90 11:32:24