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. -- {decwrl,hplabs}!nsc!baum@apple.com (408)973-3385