On 2018-Jan-01, at 5:06 PM, Paul Koning via cctalk wrote: >> On Jan 1, 2018, at 3:57 PM, David Bridgham via cctalk >> <cctalk@classiccmp.org> wrote: >> On 01/01/2018 03:33 PM, Noel Chiappa via cctalk wrote: >>>> From: Paul Koning >>> >>>> The only asynchronous computer I can think of is the Dutch ARRA 1 >>> >>> Isn't the KA10 basically asynchronous? (I know, it has a clock, but I'm >>> not sure how much it is used for.) >> >> This was my understanding, as well. >> >> More recently there was the AMULET processors designed at the University >> of Manchester. >> >> https://en.wikipedia.org/wiki/AMULET_microprocessor >> >> One of the stories I read about the AMULET was that they wrote a little >> program to blink an LED where the timing was determined by a busy loop. >> If they sat a hot cup of coffee on the processor, the light would blink >> slower; a cup of ice water and it would blink faster. > > Neat. I found this 2011 paper that's interesting: > http://www.cs.columbia.edu/~nowick/nowick-singh-ieee-dt-11-published.pdf > > The company I was trying to remember is Fulcrum, which was bought by Intel; > they had morphed into an Ethernet switch chip company by then. A pretty good > one, as I recall. But the original concept was a microprocessor, possibly a > MIPS one, I don't remember. The idea was that the chip speed would depend on > how fast things happened to work, so different chips would run at different > speeds due to process variations, and power supply and temperature changes > would also affect things just as you described. > > The paper I just mentioned lists a number of early computer designs as > asynchronous, though it doesn't mention the ARRA 1, probably because it's not > well known (a problem common to Dutch computers). Also, those other > computers did work.
The IAS machine (1952, and in some measure a template design for modern processors) and its clones (ILLIAC, ORDVAC, MANIAC, etc.) were billed as an asynchronous design, although I haven't seen the details to see precisely what that meant in context.
