Elastic Bundles: Modelling and Synthesis of Asynchronous Circuits with Granular Rigidity

Abstract

Elastic circuit design is a revolutionary step in VLSI design paving the way for commercial adoption of asynchronous design techniques. With a growing trend of synchronousasynchronous CAD tool flow integration, this paradigm shows promise to survive market forces of the semiconductor industry mainly due to scope for reuse of synchronous functional blocks and IP cores, and coexistence of synchronous and asynchronous design styles in a common EDA framework. In this paper, we introduce 'Elastic Bundles', a novel class of elastic circuits, and propose a method for modelling, designing and synthesising these circuits. Starting with a high-level dataflow model of a system, which is natively asynchronous, the key idea is to introduce rigidity of chosen granularity levels without changing functional behaviour. The resulting model is then partitioned into functional blocks of fine-grained and coarse-grained asynchronous elements that would finally be transformed to equivalent circuit descriptions for system logic synthesis using standard EDA tools. The methodology is illustrated using a case study of a 16-point FFT circuit design, which clearly demonstrates a spectrum of solutions that can be achieved in different levels of bundling granularity.

Practical Distributed Implementation of Very Large Scale Petri Net Simulations

“…It has been applied to PN simulations, first, using a centralized event scheduler and then followed by a fully asynchronous decentralized solution based on complex multi-phase communication protocols [13]. In addition to execution concurrency, PN partitioning across multiple execution devices also poses a challenge as it has a substantial impact on the amount of inter-device communication [14].…”