Temporal Adaptation – Asynchronicity in Processor Design

  • Steve Furber
  • Jim Garside
Part of the Series on Integrated Circuits and Systems book series (ICIR)


Throughout most of the history of the microprocessor, designers have employed an approach based on the use of a central clock to control functional units within the processor. While there are situations – such as the musicians in a symphony orchestra or the crew of a rowing boat – where global synchrony is a vital aspect of the overall functionality, a microprocessor is not such a system. Here the clock is merely a design convenience, a constraint on how the system’s components operate that simplifies some design issues and allows the use of a well-developed VLSI design flow where the designer can analyse the entire system state at any instant and use this to influence the transition to the next state. The clock has become so dominant in modern processor design that few designers ever stop to consider dispensing with it; however, it is not necessary – synchronisation may be restricted to places where it is essential to function.

Although a tremendous aid in simplifying a...


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Steve Furber
    • 1
  • Jim Garside
    • 1
  1. 1.The University of ManchesterUK

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