Component-Based Asynchronous Circuit Design in B

Action systems offer a component-based approach to circuit design. Component-based approaches are well established in hardware design, but are only recently more established in software design. However, software oriented methods allow a higher level of abstraction than the often quite low-level hardware design methods used today. We propose a method to organise a large circuit derivation within the B Method via its library facilities as provided by the tools. The developer proceeds from an abstract high-level specification of the intended behaviour of the target circuit via correctness preserving transformation steps towards an implementable circuit description. At each step some part of the specification is implemented using a library component chosen by the designer and the correctness of the step is proved using the tool support of the B Method. We develop the needed program transformation rules that the designer can appeal to when using library components in his or her design.