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From: shirriff@sprite.berkeley.edu (Ken Shirriff)
Newsgroups: sci.electronics
Subject: Re: VCR PLUS+ -- size of the code space
Keywords: encoding
Message-ID: <1991May6.221042.12365@agate.berkeley.edu>
Date: 6 May 91 22:10:42 GMT
References: <4764@osc.COM> <1991May6.165343.5041@msuinfo.cl.msu.edu> <42693@netnews.upenn.edu>
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In article <42693@netnews.upenn.edu> touch@cis.upenn.edu (Joseph D. Touch) writes:
>Has anyone considered how much information is in this short code?

Questions I have for someone with an appropriate VCR:

How does the VCR process variable length codes?
a) Is there an explicit end-of-code terminator?
   i.e. do you enter 55 <record> and 551234 <record> for different codes?
b) Or is no short code a prefix of a longer code?
   i.e. if there is a code 55, there is no code 551234, and the VCR knows
   after receiving 55 that this is the end.

And if anyone can determine if the code space is dense (i.e. every code
does something without an error), and unique (no two codes do the same
thing), this would be interesting to know.

Finally, my TV listings only give codes for prime-time to late night shows.
Do the codes do anything strange for daytime shows?

Ken Shirriff			shirriff@sprite.Berkeley.EDU