Path: utzoo!attcan!uunet!pyrdc!pyrnj!rutgers!apple!baum
From: baum@Apple.COM (Allen J. Baum)
Newsgroups: comp.arch
Subject: Re: non-binary hardware
Message-ID: <17361@apple.Apple.COM>
Date: 19 Sep 88 17:29:30 GMT
References: <1285@mcgill-vision.UUCP> <3473@phri.UUCP> <5718@utah-cs.UUCP> <655@calvin.EE.CORNELL.EDU> <2997@pt.cs.cmu.edu> <17234@apple.Apple.COM> <8756@srcsip.UUCP>
Reply-To: baum@apple.UUCP (Allen Baum)
Organization: Apple Computer, Inc.
Lines: 19

[]
>In article <8756@srcsip.UUCP> shankar@ely.UUCP (Subash Shankar) writes:
>The proof (of optimality of base-e hardware) is as follows:
>
>  Assume that hardware cost per digit is linearly proportional to the radix. 
> ..... (the proof)
>There is a serious flaw in this proof - it is not at all clear that the
>hardware cost per digit is linearly proportional to the radix; hence the
>controversy over the "optimal" radix remains an open question.  A second
>flaw is that the above shows optimal radices for functional components such
>as ALU's, but with interconnect being more important on chips, multi-valued
>logic may be of great use.

Agreed that the proof is flawed, but there are reasons that work both ways,
like signal-to-noise being worse, and settling times increasing. Anyway, a
book reference for the proof: "High Speed Computing Devices" by ERA Associates,
McGraw-Hil, 1950(!) pg 84. They talk about relays and triode logic a lot.

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