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- Newsgroups: comp.lang.c++,comp.programming,comp.arch
- Path: uu4news.netcom.com!friend!news
- From: rich@kastle.com (Richard Krehbiel)
- Subject: Re: Why are 32 bit better than 16 bit pgms?
- Message-ID: <1996Feb8.181534.4170@friend.kastle.com>
- Sender: news@friend.kastle.com (News)
- Reply-To: rich@kastle.com
- Organization: Kastle Development Associates
- X-Newsreader: Forte Free Agent 1.0.82
- References: <4er4m4$78q@news1.ucsd.edu> <1996Feb5.163838.24531@amc.com> <1996Feb6.135808.12257@friend.kastle.com> <4f9e3p$alp@murrow.corp.sgi.com>
- Date: Thu, 8 Feb 1996 18:15:13 GMT
-
- mash@mash.engr.sgi.com (John R. Mashey) wrote:
-
- >In article <1996Feb6.135808.12257@friend.kastle.com>, rich@kastle.com (Richard Krehbiel) writes:
- >|>
- >|> curtis@amc.com (Curtis Green) wrote:
- >|>
- >|> >The "bits" quoted for the processor (16 bit, 32 bit, 64 bit, etc) is the
- >|> >size of the data path (data bus).
- >One more time, since this has been discussed here about every 6 months:
- >through computer history, there has been one overpoweringly common usage:
-
- > An N-bit architecture has an ISA with N-bit integer registers.
-
- >Implementations of such an architecture can vary all over the map:
-
- Well, that's what I was talking about.
-
- > 1) FP registers frequently have different sizes [>=N]
- > 2) Internal busses, even the integer ones, occasionally use different
- > sizes [<= N]
- > 3) External busses frequently have different sizes [=N, <N, >N]
-
- >|> My humble opinion:
- >|>
- >|> "Bitness" has become a marketing term, i.e. meaningless (rather like
- >|> the term "RISC"). There are a dozen different pieces inside a CPU
-
- >Consider studying computer history more or reading this newsgroup more often ...
-
- Oh, I read these newsgroups all the time. I think you just don't want
- to hear me to say that I don't think it's all that important that the
- R4000/8000/10000 are "64-bit" architectures. :-)
-
- >1) This term has had a long and consistent history of use, with only
- >occasional excursions into marketing aberration (i.e., like calling
- >the i860 a 64-bit processor).
-
- Since there are "occasional excursions" by marketers, I believe it's
- not all that well defined.
-
- BTW I do remember the i860 (64 bit bus, 32 bit otherwise). I remember
- flame war a'plenty about calling the 8088 an 8 bit vs 16 bit CPU, the
- 68000 a 16 bit vs 32 bit CPU, the 80386SX a 16 bit vs 32 bit CPU, the
- Pentium a 32 bit vs 64 bit CPU. I recall discussions on whether it's
- useful to consider the Alpha AXP a 64 bit CPU when you're running
- Windows NT, and the same for the MIPS R4000 for that matter.
-
- --
- Richard Krehbiel, Kastle Systems, Arlington VA USA
- rich@kastle.com (work) or richk@mnsinc.com (personal)
-
-