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Timeless Truths about Sequential Circuits

  • Geraint Jones
  • Mary Sheeran

Abstract

We suggest the use of a declarative programming language to design and describe circuits, concentrating on the use of higher-order functions to structure and simplify designs. In order to describe sequential circuits, we use a language, µ fp, which abstracts from temporal iteration. The practicalities of vlsi design make regularity attractive, and we describe the use of familiar higher order functions to capture spatial iteration.

By reasoning about circuits rather than signals (programs rather than data) one abstracts from the sequential nature of a circuit. By reasoning about forms of circuit (higher order functions) one can devise implementation strategies for whole classes of algorithms. Reasoning about µ fp is formally quite similar to reasoning about fp.

In this paper we identify the semantic content of the formal similarity between fp and µ fp. This makes it possible to carry over from conventional functional programming those intuitions we have about algorithm design. It also makes it possible to conduct parts of a design in the simpler world of static calculations, with confidence in the correctness of the corresponding sequential circuit.

Keywords

Infinite Sequence Sequential Circuit Combinational Circuit High Order Function Equational Reasoning 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1988

Authors and Affiliations

  • Geraint Jones
    • 1
  • Mary Sheeran
    • 2
  1. 1.Oxford University Computing LaboratoryOxford UniversityUK
  2. 2.Dept. of Computing ScienceUniversity of GlasgowUK

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