A high performance programmable controller for CIM systems based on Petri net theory

The authors propose a novel control architecture to realize high-performance programmable controllers which have the features especially suited to CIM (computer-integrated manufacturing) systems: a simple hardware and simultaneous execution of many functional jobs. The execution time of sequence control was decreased by adopting the Petri net theory to its task switching, which enabled the developed PC to perform other jobs, such as servo control, communications, information processing, and so on, under a time sharing condition. All jobs were driven by interrupt requests, which simplify the construction of the operating system. A compact operating system is proposed for dispatching these jobs effectively.<
>