yodaiken@freal.cs.umass.edu (victor yodaiken) (10/04/89)
In the June 89 SIGARCH there's an article by Martin, Burns and a couple of other folks from CALTECH on using the self-timed (asynchronous) circuits that they've been pushing at CALTECH to build a processor. The paper and chip look interesting, but there's a lack of details. Any comments on this work out there? Any comments on self-timed circuits themselves?
haynes@ucscc.UCSC.EDU (Jim Haynes) (10/05/89)
In article <5241@dime.cs.umass.edu> yodaiken@freal.cs.umass.edu (victor yodaiken) writes: >In the June 89 SIGARCH there's an article by Martin, Burns and a couple ... I haven't seen that article, but see Ivan Sutherland's Turing Award Lecture printed in a recent issue of CACM. haynes@ucscc.ucsc.edu haynes@ucscc.bitnet ..ucbvax!ucscc!haynes "Any clod can have the facts, but having opinions is an Art." Charles McCabe, San Francisco Chronicle
paul@taniwha.UUCP (Paul Campbell) (10/05/89)
In article <5241@dime.cs.umass.edu> yodaiken@freal.cs.umass.edu (victor yodaiken) writes: >In the June 89 SIGARCH there's an article by Martin, Burns and a couple >of other folks from CALTECH on using the self-timed (asynchronous) >circuits that they've been pushing at CALTECH to build a processor. >The paper and chip look interesting, but there's a lack of details. I liked the bit when they put it in liquid nitrogen and got about twice as many MIPS out of it (being self-timed it has no clocks and only depends on internal delays to slow it down). Of course self-timed logic takes up more space .... >Any comments on this work out there? Any comments on self-timed >circuits themselves? Read this year's Turing Address in CACM a few months back. Paul -- Paul Campbell UUCP: ..!mtxinu!taniwha!paul AppleLink: D3213 "Free Market": n. (colloq.) a primitive fertility goddess worshipped by an obscure cult in the late 20th C. It's chief priest 'Dow Jones' was eventually lynched by an enraged populace during an economic downturn (early 21st C).
johng@prism.cs.orst.edu (John A. Gregor) (10/05/89)
In article <5241@dime.cs.umass.edu> yodaiken@freal.cs.umass.edu (victor yodaiken) writes: >In the June 89 SIGARCH there's an article by Martin, Burns and a couple >of other folks from CALTECH on using the self-timed (asynchronous) >circuits that they've been pushing at CALTECH to build a processor. Perfect timing! For my EE 478 (Computer Architecture) class we have to do a report and a presentation. I'm looking at doing mine on asynchronous logic design. Does anyone out there have some good references? Any personal experiences, observations, warnings, anecdotes, etc. you wish to share? Also, what I really need are some pointers to actual machines or subsystems that have been implemented in asynchronous logic. All information will be greatly appreciated. I'll summarize what I get if there is interest. John Gregor 423 Cauthorn Hall johng@cloud.ATS.ORST.EDU Oregon State University (503) 737-8426 Corvallis, OR 97331
lindsay@MATHOM.GANDALF.CS.CMU.EDU (Donald Lindsay) (10/05/89)
In article <9320@saturn.ucsc.edu> haynes@ucscc.UCSC.EDU.UUCP (Jim Haynes) writes: >see Ivan Sutherland's Turing Award Lecture >printed in a recent issue of CACM. Specifically, it's "Micropipelines" Turing Award Lecture Ivan E. Sutherland Communications of the ACM, June 1989 (32, 6, 720-738) Easy to find, it's just before the killer Literate Programming column. Also, I saw a book by Dave Dill in the latest blurb from MIT Press. My main reactions to "Micropipelines" were: 1) Sounds promising. 2) Isn't transition signalling noise-susceptible? The Sigarch article is "The First Asynchronous Microprocessor: The Test Results" Martin, Burns, Lee, Borkovic, Hazewindus Computer Architecture News, June 1989 (17, 4, 95-110) 3) Fast! Smaller than I expected, too. 4) Neato design method. 5) One reason that asynchronous systems fell into disfavor, was that they were often slightly wrong. They would have low-probability failure modes. Supposedly, the new methods give circuits which are guaranteed correct. So, I'm a bit worried by the line on P.96: "We cannot explain the phenomena yet." 6) A famous reason for synchronous systems, is that one can make all of the electrical noise happen at once, and arrange that no one is listening then. Self-timed circuits can't do this: what do they do instead? 7) Is it really necessary to independently self-time each and every line in a bus? -- Don D.C.Lindsay Carnegie Mellon Computer Science
baum@Apple.COM (Allen J. Baum) (10/06/89)
[] >In article johng@cloud.ATS.ORST.EDU (John A. Gregor) writes: >For my EE 478 (Computer Architecture) class we have to do a report and >a presentation. I'm looking at doing mine on asynchronous logic >design. Does anyone out there have some good references? Any personal >experiences, observations, warnings, anecdotes, etc. you wish to >share? Also, what I really need are some pointers to actual machines >or subsystems that have been implemented in asynchronous logic. > The only asynchronous machine that I'm aware of (outside of the recent Caltech micro) is the Illiac II. There are probably research reports still available. -- baum@apple.com (408)974-3385 {decwrl,hplabs}!amdahl!apple!baum
root@cca.ucsf.edu (Systems Staff) (10/06/89)
In article <35307@apple.Apple.COM>, baum@Apple.COM (Allen J. Baum) writes: > > The only asynchronous machine that I'm aware of (outside of the recent > Caltech micro) is the Illiac II. There are probably research reports still > available. Back around 1959-61 there were the Philco machines that used asynchronous logic. I used a model 209 at the Western Development Laboratory and they had a faster machine out called the 211. They were working on a new one called the 212 which got running just about the time Ford took them over. It was a very fast machine for its time but Ford had decided in advance that they were going to scrap the computer division so it went down the tubes. There is an amusing anecdote about the first 212 installed. It was scheduled in advance for the batch processing chores it was to do for a single shift operation. Surprise, it finished all the scheduled work by lunch time and everybody took the afternoon off. It's the only case I know of where a new machine came in exceeding the predicted performance level by such a substantial factor. Thos Sumner Internet: thos@cca.ucsf.edu (The I.G.) UUCP: ...ucbvax!ucsfcgl!cca.ucsf!thos BITNET: thos@ucsfcca U.S. Mail: Thos Sumner, Computer Center, Rm U-76, UCSF San Francisco, CA 94143-0704 USA I hear nothing in life is certain but death and taxes -- and they're working on death. #include <disclaimer.std>