Handling timing constraints in rapid prototyping

Concepts and mechanisms for handling the real-time constraints of embedded software systems in rapid prototyping are presented. Rapid prototyping of embedded systems can be accomplished using a computer-aided prototyping system, CAPS, and its associated prototyping language PSDI. This system and language are used to aid the designer in the early stages of software engineering for hard real-time systems. Such systems contain time-critical operations with maximum execution times, maximum response times, and minimum calling periods. Interrupt handling, synchronization, and periodic behavior are also described at a high level. Time-critical operations in a real-time prototype are handled by constructing static and dynamic schedules to coordinate execution and to meet the required prototype execution times. The mechanisms for expressing timing constraints in PSDL are described along with their effects on the schedulers