Resolving unknown inputs in mixed-level simulation with sequential elements

It is well known that techniques such as performance modeling that can effectively evaluate design alternatives early in the design process can greatly increase the quality of the ultimate implementation, while at the same time, decrease the design time. In order to gain the maximum benefit from performance modeling, it must be integrated into the design process such that the performance model can be directly refined into an implementation. This paper presents techniques for developing interfaces between abstract performance models and detailed behavioral models to enable this refinement process. These mixed-level modeling interfaces, as they are called, allow abstract performance models to be cosimulated with detailed behavioral models. Because of the differences in the level of detail between abstract performance models and detailed behavioral models, not all of the inputs to the behavioral model can be derived from information in the performance model. Techniques for determining values for these “unknown” inputs are presented, These techniques have been designed to generate bounds on the system performance that converge as the model is refined