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General microprogram width reduction using generator sets

Published:01 December 1981Publication History
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Abstract

The problem of reducing the microinstruction length for a parallel microprogram, by trading off microprogram width (bits) for subsequent logic, is considered. In a generalization of previous methods, it is shown that a considerable reduction of microprogram storage size can be achieved by selecting a subset of the original microorders to serve as inputs to some generating logic in order to provide all the microorders in the original microprogram. Heuristic solution methods are shown, along with ways to control the bounds of the solutions, allowing the designer the choice between a fast solution and an optimal solution. Examples show the effects of using these methods, alone and in conjunction with previously published methods for width reduction. Applications of the width reduction technique to reasonable modern design situations are discussed.

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        • Published in

          cover image ACM SIGMICRO Newsletter
          ACM SIGMICRO Newsletter  Volume 12, Issue 4
          Dec. 1981
          187 pages
          ISSN:1050-916X
          DOI:10.1145/1014192
          Issue’s Table of Contents
          • cover image ACM Conferences
            MICRO 14: Proceedings of the 14th annual workshop on Microprogramming
            December 1981
            214 pages

          Copyright © 1981 Authors

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          Association for Computing Machinery

          New York, NY, United States

          Publication History

          • Published: 1 December 1981

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