An Ada runtime environment supporting the development of verifiable real-time software for embedded modular avionic systems

The Ada programming language has been criticized for lacking essential runtime system capabilities which support the generation of verifiable, real-time multitasking software. Such a capability is critical to the development of application software for high performance embedded avionic systems. The Ada Real-Time Machine Interface (ARTMI) software component of the F-16 Modular Mission Computer (MMC) provides Ada runtime environment (RTE) extensions that support development of real-time multitasking application software. The extensions eliminate the problem of mutual deadlock and unbounded priority inversion at critical sections through use of the priority ceiling protocol. This allows application software to be designed with task prioritization schemes that permit application of Rate Monotonic Analysis techniques. In addition, the extensions support execution time modification of task priorities. Such a capability can be used to reallocate processing bandwidth to critical system functions as the demands of a mission change