Simulink-based hardware/software trade-off analysis technique

Fast analysis of hardware/software trade-offs for cost, performance and power-constrained embedded systems is a key to reduce the time to market and at the same time improve the quality of results. However, this analysis must also be close to the final results of the detailed HW and SW implementation in order to lead to an optimal solution. This requires the use of compilation (for SW) and synthesis (for HW) techniques that ensure the existence of a solution with the estimated cost, and are not too far from what will later be achieved by manual optimization and detailed design. We start from a realistic application domain, namely sound-triggered wireless security cameras, and we show in detail how one can start from an algorithm modeled and validated using Simulink, and using commercial state-of-the-art tools explore various possible hardware and software implementations for the frequency based audio detection front end, with respect to the overall design constraints and goals. We show how rapid estimations of the various aspects of the cost function can be obtained quickly, using directly the C code generated from Simulink, with a few manual refinements in order to increase the efficiency of both software and hardware implementations and bring them closer to the final optimized implementation. We report results showing different points in the design space. The results that we obtained are close to manual hand optimized implementations for both HW and SW, showing that the approach is useful for trade-off analysis in a very short time, and that further manual optimizations can quickly lead to the best implementation.