School of Computer Science Intranet
Lilian Janin and Doug Edwards
Asynchronous circuit design shows many similarities with software design. This is due to the modular construction style associated with asynchronous circuits, where each asynchronous module is designed as a standalone object communicating with other modules. We propose a visualisation system for asynchronous circuit design tools, based on clustered graph visualisation and coordinated views. The novelty of our approach is to apply classical software visualisation techniques to a hardware environment and take advantage of properties specific to our asynchronous design flow. This system is based on a control and data flow graph representation of the asynchronous circuit compiled from a high-level description by a syntax-directed transparent process and transferable to the final hardware circuit by a direct synthesis process. Compared to software compilation flows, this transparent design flow offers opportunities for visualisation, with representations at different stages being easily mapped onto each other to combine their visualisation qualities. Each representation also exhibits properties based on some physical attributes of the final hardware circuit, allowing us to render some abstract properties on top of real-world-based ones. This paper shows how the handshake circuit graph is used as the underlying structure onto which properties extracted from other structures are mapped, and then how this structured graph is used as the central piece in a coordinated views environment. These visualisation techniques have been exercised by designers optimising the design of a fully asynchronous ARM processor.