Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!apple!tahoe!jimi!charlie.cs.unlv.edu!maniac
From: maniac@charlie.cs.unlv.edu (Eric J. Schwertfeger)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: Bizarre Fantasy: RLL Flopies?
Keywords: MFM, RLL, Floppies, Blitter, Clueless, Fantasy, etc.
Message-ID: <1991Apr3.233902.19052@unlv.edu>
Date: 3 Apr 91 23:39:02 GMT
References: <1991Apr2.061633.17980@kessner.denver.co.us> <1034@cbmger.UUCP>
Sender: news@unlv.edu (News User)
Reply-To: maniac@charlie.cs.unlv.edu (Eric J. Schwertfeger)
Followup-To: comp.sys.amiga.hardwareIn article <1034@cbmger.UUCP>,
Organization: UNLV Computer Science and Electrical Engineering
Lines: 20

In article <1034@cbmger.UUCP>, peterk@cbmger.UUCP (Peter Kittel GERMANY) writes:
[about GCR Encoding]

)  The caveat is that the Amiga hardware
) (Paula?) can't read this reliably and must be cut down to half speed,
) so effectively you gain only 4 bits out of 10. So finally MFM is more
) effective and used for that reason.
) 
) I have no idea whether this could change with today's more advanced
) technology. Also have no idea whether implementation of RLL would 
) need new custom chip(s).
) 
) -- 
) Best regards, Dr. Peter Kittel  // E-Mail to  \\  Only my personal opinions... 
) Commodore Frankfurt, Germany  \X/ {uunet|pyramid|rutgers}!cbmvax!cbmger!peterk

	I've heard this before, but still have one question.  Just *WHAT* is it that the hardware can't correctly read at full speed?  Two consecutive on bits, or 8 consectutive off bits?  I've been toying around with alternate encoding schemes, and I can get around either of these, but not both, and still get 25%-50% more on a disk.  I just don't know what I need to avoid, until I get my code working (could be a long time, without a hard disk).

-- 
Eric J. Schwertfeger, maniac@jimi.cs.unlv.edu