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A Coarse-Grain Phased Logic CPU
July 2005 (vol. 54 no. 7)
pp. 788-799
This paper describes an asynchronous design tool flow known as Phased Logic that converts a clocked design into an asynchronous design implemented as a micropipeline using two-phase control and bundled data signaling. Example designs include variations of a double-precision floating-point clipping operation mapped to two commercial standard cell libraries (0.18µ and 0.13µ) and a five-stage pipelined MIPs-compatible integer unit mapped to the 0.13µ library. The design style includes a feature known as early evaluation, which is a generalized form of bypass, that allows the self-timed design to recover some of the inherent latch delay penalty in micropipelines.

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Index Terms:
Index Terms- Automatic synthesis, self-timed, asynchronous, pipelined processor, micropipelines.
Robert B. Reese, Mitchell Aaron Thornton, Cherrice Traver, "A Coarse-Grain Phased Logic CPU," IEEE Transactions on Computers, vol. 54, no. 7, pp. 788-799, July 2005, doi:10.1109/TC.2005.105
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