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What happened to clockless computer chips?

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Re: What happened to clockless computer chips?

#3
"The answer is that although the chip ran three times as fast and used half the electrical power as clocked counterparts..."

I thought another advantage was that it modularized chip design to some degree - ie you can improve individual sections to run much faster, without having to make the entire chip run at that speed - http://www.cs.virginia.edu/~robins/Computing_Without_Clocks....

In any case in a similar vein is TTA (https://en.wikipedia.org/wiki/Transport_triggered_architectu...) which I think Ivan Sutherland was also involved in, but maybe I'm wrong about that.

Re: What happened to clockless computer chips?

#6

Anyone here working on async chips these days?

I used to work at a startup ( https://www.linkedin.com/company/azuro ) that was commercialising the founders' work on asynchronous design. They eventually sold to Cadence.

Asynchronous design is a huge sell; we scaled it back to just applying some async techniques to the clock tree of synchronous designs for moderate performance/power improvements.

There are three problems we found:

- the existing toolchain is synchronous-orientated, so you'd have to replace all of it and retrain your staff.

- the chip developers and their managers tend to be older and more conservative than the software world. They're also potentially large teams (Intel are obviously huge). So the retraining is going to be difficult and expensive.

- it's risky. New toolchain and newly trained staff? There's going to be bugs in the tools and errors in the design. Worse, there will be new types of bug that people aren't good at diagnosing. These will take weeks to resolve and a couple of wafer sets. That's a very expensive proposition!

If async is to get a foothold it would be, like ARM, starting at the low end. Low power consumption is an obvious pitch for microcontrollers, and the simpler designs will be less risky.

Re: What happened to clockless computer chips?

#7
post #6

Anyone here working on async chips these days?

I used to work at a startup ( https://www.linkedin.com/company/azuro ) that was commercialising the founders' work on asynchronous design. They eventually sold to Cadence. Asynchronous design is a huge sell; we scaled it back to just applying some async techniques to the clock tree of synchronous designs for moderate performance/power improvements. There are three problems we found: - the existing toolchain is synchr…

ARM tried it in the 90s with the AMULET.

https://en.wikipedia.org/wiki/AMULET_microprocessor

Re: What happened to clockless computer chips?

#8
post #5

Nearly all chips have frequency scaling nowadays, so it is close to async tech. Intel got the turbo and XFR from AMD steps it up even more. You can only do so much with general purpose processors. After that point you just gotta go ASICS.

Variable clock frequency is something very different from being clockless.

Clockless architecture is also not about the general processor design.

Re: What happened to clockless computer chips?

#10
post #6

Anyone here working on async chips these days?

I used to work at a startup ( https://www.linkedin.com/company/azuro ) that was commercialising the founders' work on asynchronous design. They eventually sold to Cadence. Asynchronous design is a huge sell; we scaled it back to just applying some async techniques to the clock tree of synchronous designs for moderate performance/power improvements. There are three problems we found: - the existing toolchain is synchr…

I'm starting to feel like a broken record but... A perfect opportunity with risc-v.
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