Task Implementation and Schedulability Analysis of Synchronous Finite State Machines

Model-based design of embedded control systems using Synchronous Reactive (SR) models is among the best practices for software development in the automotive and aeronautics industry. Previous research focused on the concurrent implementation of the dataflow part of SR models, including the optimization of the block-to-task mapping and the optimization of the communication buffers. When the system is composed of blocks implementing finite state machines, as in modeling tools like Simulink and SCADE, the task implementation can be further optimized with respect to time and memory. In this paper we analyze problems and opportunities in the implementation and analysis of finite state machine subsystems. We define the constraints and efficient policies for the block to task implementation and we introduce the schedulability analysis of these systems.