Article View: comp.sys.atari.st
Article #26872Re: Twister, Format+
From: Richard Sansom
Date: Mon, 18 May 1987 15:29
Date: Mon, 18 May 1987 15:29
32 lines
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2122 bytes
In article <719@ttidca.TTI.COM> woodside@ttidcb.UUCP (George Woodside) writes:
>TWISTER compensates for the track step/head settle/position verify
>time by staggering the sectors on the tracks in relation to the index mark,
>like this:
>
> INDEX---+ Sectors
>(TRK 00) ! 1 2 3 4 5 6 7 8 9 10
>(TRK 01) ! 3 4 5 6 7 8 9 10 1 2
>(TRK 02) ! 5 6 7 8 9 10 1 2 3 4
I think that twisting is backwards - shouldn't it be:
(TRK 00) ! 1 2 3 4 5 6 7 8 9 10
(TRK 01) ! 9 10 1 2 3 4 5 6 7 8
(TRK 02) ! 7 8 9 10 1 2 3 4 5 6
otherwise, you'll have to wait for 7-8 sectors to pass before sector 1 comes
around again. Also, if you look at the original code (file mmtwst.c, I think)
you'll see that is the way Twister actually does it.
I modified Twister to allow user spcification of sectors per track and
tracks per side. I was hoping to get Atari's permission to post using the
(Atari copyrighted) FDC code which was published with Twister, but,
unfortunately, never got a reply (and I'm too lazy to completely rewrite the
code).
-Rich
--
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/// Richard E. Sansom TRW Electronics & Defense Sector \\\
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!mnetor!seismo!rutgers!mit-eddie!genrad!decvax!ucbvax!hplabs!sdcrdcf!trwrb!sansom From: sansom@trwrb.UUCP (Richard Sansom) Newsgroups: comp.sys.atari.st Subject: Re: Twister, Format+ Message-ID: <1902@trwrb.UUCP> Date: Mon, 18-May-87 11:29:07 EDT Article-I.D.: trwrb.1902 Posted: Mon May 18 11:29:07 1987 Date-Received: Tue, 19-May-87 04:13:11 EDT References: <8705081618.AA15013@ucbvax.Berkeley.EDU> <13104@watmath.UUCP> <967@batcomputer.tn.cornell.edu> <719@ttidca.TTI.COM> Reply-To: sansom@trwrb.UUCP (Richard Sansom) Distribution: world Organization: TRW EDS, Redondo Beach, CA Lines: 32