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From: u-dmfloy%sunset.utah.edu@utah-cs.UUCP (Daniel M Floyd)
Newsgroups: comp.lang.c
Subject: Re: non-binary hardware
Message-ID: <5718@utah-cs.UUCP>
Date: 11 Sep 88 03:38:11 GMT
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Reply-To: u-dmfloy%sunset.utah.edu.UUCP@utah-cs.UUCP (Daniel M Floyd)
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I've been toying with an idea along these lines for a while.
I've done some preliminary research and it's real sketchy.
The theme is along the trinary and up system. I don't think
digital systems like this have ever been built. Obviously
we can't count the n-ary as n goes to infinity because that's an
analog computer. A major problem with anything except binary (I'm
refering to BCD etc here too), is achieving the third, fourth, and
nth stable state. I can't count tri-state (i.e. bus circuits). The
third state with them is floating. If the bus wants high, the
float says "ok". Same if the bus wants low. For true trinary, the
circuit would complain if the bus tried any other level than what
it wanted. (I hope everyone doesn't mind the anthropomorphism.)
I've looked at several alternative trinary logic levels. No one
has given me a convincing argument about which is correct yet.

For example:

Trinary 'AND':

    0 1 2              0 1 2
=========          =========
0 | 0 0 0          0 | 0 0 0
1 | 0 1 2          1 | 0 1 2
2 | 0 2 2          2 | 0 2 1


Both have merits. I supose you could define them as AND2 and AND1.

Let's see what all of you have to say.