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 correctnesspreserving 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.