A Distributed Real-Time Operating System with Prioritized Inter-Node System Calls for Distributed Embedded Control Systems

The paper presents a distributed real-time operating system (DRTOS) that provides prioritized inter-node system calls for location-transparent task management and inter-task synchronization. Embedded control software is usually designed as a set of tasks, which are managed according to their priorities by a real-time operating system. In a distributed embedded control system, not only task execution on each node but also inter-node communication should be managed according to their priorities. The DRTOS presented in this paper provides location-transparent inter-node system calls for task management and event control. The inter-node system calls are managed according to the priorities of the tasks that issues the system calls. The prioritized inter-node system calls are implemented using the prioritized communication mechanism of a CAN network. By using the DRTOS, we can develop a distributed control application program without considering the distributed environment and easily reallocate distributed tasks without rewriting the source code. The experimental evaluation results show that the performance of the inter-node system calls is acceptable for distributed embedded control systems with CAN networks.