Hardware design of a real‐time Petri net model for real‐time tasks

A real time Petri net (RTPN) model is proposed to model the task specification of a real time system in terms of events, actions, states, and temporal constraints. The basic operations of a RTPN include executable transition identification, marking updating, temporal constraint check, and shared input/output calculation. These are time‐consuming processes on whatever computers they are executed. A hardware‐implementable execution model is proposed to improve their performance. Detailed hardware designs of the event and state matching modules in the execution model are described. They employ an associative technique to provide massive parallelism needed in the modules. Moreover, the time complexities of the event and state matching modules are constant, which allows us to better control or predict the behavior of a real time task — a very important feature in a real‐time system.