Jordi Cortadella

Designing asynchronous circuits from behavioural specifications with internal conflicts

The paper presents a systematic method for synthesizing asynchronous circuits from event-based specifications with conflicts on output signals. It describes a set of semantic-preserving transformations performed at the Petri net level, which introduce auxiliary signal transitions implemented by internally analogue components, Mutual Exclusion (ME) elements. The logic for primary outputs can therefore be realized free from hazards and external meta-stability. The technique draws upon the use of standard logic components and two-input MEs, available in a typical design library.

Automatic synthesis and optimization of partially specified asynchronous systemsProceedings 1999 Design Automation Conference (Cat. No. 99CH36361)

A method for automating the synthesis of asynchronous control circuits from high level (CSP-like) and/or partial STG (involving only functionally critical events) specifications is presented. The method solves two key subtasks in this new, more flexible, design flow: handshake expansion, i.e. inserting reset events with maximum concurrency, and event reshuffling under interface and concurrency constraints, by means of concurrency reduction. In doing so, the algorithm optimizes the circuit both for size and performance. Experimental results show a significant increase in the solution space explored when compared to existing CSP-based or STG-based synthesis tools.