New approaches for distributed industrial process control systems aimed to cope with strict time constraints

Four approaches aimed to cope with strict timing constraints as encountered in industrial process control applications are presented. For each node in a distributed system, an asymmetrical two-processor architecture is used that is capable of guaranteeing response times. One processor in each node is dedicated to the kernel of a real-time operating system. Its three reaction levels are constructively described by outlining their functional units and control procedures. It is shown that some problems of real-time computers can be solved by endowing the node computers with process peripherals