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From: news@ism780c.isc.com (News system)
Newsgroups: comp.lang.c
Subject: Re: non-binary hardware (was: Absolute size of 'short')
Message-ID: <15565@ism780c.isc.com>
Date: 13 Sep 88 20:43:35 GMT
References: <1285@mcgill-vision.UUCP> <297@sdti.UUCP> <6266@venera.isi.edu>
Reply-To: marv@ism780.UUCP (Marvin Rubenstein)
Organization: Interactive Systems Corp., Santa Monica CA
Lines: 20

In article <6266@venera.isi.edu> lmiller@venera.isi.edu.UUCP (Larry Miller) writes:
>>By the way, does anyone know of a non-mechanical digital calculator or
>>computer that isn't essentially binary?
>
>    There was also the IBM 1620, a BCD machine.  Yes, decimal, but
>    all arithmetic was performed using table lookup, floating point
     ^^^
>    in software, so I guess it could be called a nonbinary machine.
>
>Larry Miller				lmiller@venera.isi.edu (no uucp)

Well, actually not quite all arithmetic was by table lookup.  Program counter
incrementing was done with traditional bcd (i.e. binary) add logic.  So I
would call even this machine binary.

BTW: There actually was hardware floating point. The harware supported
floating precision of from 2 decimal digits to an upper bound on precision
limited only by the amount of memory available to hold the data.

   Marv Rubinstein