A REAL-TIME OPERATING SYSTEM DESIGNED FOR PREDICTABILITY AND RUN-TIME SAFETY

Abstract

Complex embedded machines are usually controlled by an application software sitting on top of a real-time oper-ating system. Thus, the safety issues involved do not apply only to the mechanical structure or to the elec-tronic circuitry, but also to the software that is responsi-ble for an efficient run-time and predictable error-handling. The single, least reliable, nonredundant piece building the system, will undermine the overall reliabil-ity of the whole machine. This paper describes a real-time operating system (XOberon) with deterministic and safe run-time behav-ior, which is easy to program and to customize. XOberon goes beyond the established concepts, like interrupt- or priority-driven scheduling, bringing in new program-ming paradigms, such as deadline-driven scheduling, automatic storage reclamation, dynamic linking and loading, memory protection, and off-line/on-line dura-tion computation.