Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!gatech!hao!ames!ucbcad!ucbvax!hplabs!sdcrdcf!psivax!csun!aeusesef From: aeusesef@csun.UUCP (Sean Eric Fagan) Newsgroups: comp.arch Subject: Re: Japanese 32-bit CPUs ( NEC V70 ) [really CISC] Message-ID: <609@csun.UUCP> Date: Thu, 14-May-87 12:00:31 EDT Article-I.D.: csun.609 Posted: Thu May 14 12:00:31 1987 Date-Received: Sat, 16-May-87 13:53:58 EDT Organization: California State University, Northridge Lines: 45 In article <277@astroatc.UUCP> johnw@astroatc.UUCP (John F. Wardale) writes: >Now the trend is to build simpler, faster REGULAR machines, and the only >thing that falls the the category of "fashionability" is terms "RISC" and >"CISC" Seymore (sp?) made a RISCy machine called the "Cray-1" before >anyone started to use the term "RISC" >A wonderful appearing "middle ground" part is the "Clipper" which is a >basic RISC machine with an additional set of "macro" instructions. >(So, we can't do MULT or DIV in one clock, we'll give you a MULT and DIV >macro in "hardware". I like this approach, but then I'm firmly rooted in >the RISC camp) >Name: John F. Wardale >UUCP: ... {seismo | harvard | ihnp4} !uwvax!astroatc!johnw >arpa: astroatc!johnw@rsch.wisc.edu Not to be nitpicky, or anything, but old Seymore did a RISC long before the Cray-1. Ever hear of the CDC Cyber line? The 6600, 7600, 170 lines? All RISC, with a grand total of about, oh, 70+ instructions. Two instructions to directly access memory, and a few instructions to indirectly access memory. Execution of non-divide, non-context save instructions in less than 10 clock cycles, generally under 5. Double precision multiply takes about 5 clock cycles, I believe (worse case). Single precision is the same, only it returns the low half. (I should mention that double precision on a Cyber is 120 bits.) Very fast floating point, slightly slower integer (yeah, slower), very nice instruction set. Lousy operating system, though, but that is not Seymore's fault. If you ever get the hardware reference manuals for both the Cray-1 and the Cyber 7600 (or a 170 model), you will notice that they are *extremely* similar, almost the same except for small things like word size, lack of a divide instruction on the Cray, no vectors on the Cyber, etc. Sorry, but I tend to ramble about the Cyber, especially when people bring up the Cray. If I misspelled Mr. Cray's first name, please forgive me... ----- Sean Eric Fagan Office of Computing/Communications Resources (213) 852 5086 Suite 2600 AGTLSEF@CALSTATE.BITNET 5670 Wilshire Boulevard Los Angeles, CA 90036 {litvax, rdlvax, psivax, hplabs, ihnp4}!csun!{aeusesef,titan!eectrsef} -------------------------------------------------------------------------------- My employers do not endorse my | "I may be slow, but I'm not stupid. opinions, and, at least in my | I can count up to five *real* good." preference of Unix, heartily | The Great Skeeve disagree. | (Robert Asprin)