From Ideal to Realisable Real-time Speciications

Formally reening a real-time speciication to an implementation is only possible when the speciication allows for all physical limitations , and timing and signal errors inherent in the implementation. Allowing for such implementation-speciic details in a top-level specii-cation can, however, obscure the desired functionality and complicate analysis. Furthermore, such an approach assumes the speciier has an understanding of the physical limitations and errors of the implementation which may not yet have been developed. As an alternative, we propose introducing a notion of realisation into the formal development process. Realisation is an approach to speciication development which allows errors and physical limitations to be introduced. It also allows properties of the new speciication to be derived from those proved for the original.