Memory reduction of fire unit for Petri net controlled multiprocessor

The authors propose a novel Petri net (PN) controller that is easy to implement by ASIC (application-specific integrated circuit). This is to be used for a PN controlled multiprocessor in which the fire unit is adopted to implement fast PN control. Reduction of memory in the fire unit is proposed. In the reduced memory fire unit, a large number of places of the whole Petri net are partitioned into a subnet and numbered individually for each subnet. Using this numbering and an additional table for the subnet place table, one can reduce by more than 90% the memory of the fire unit. Two memory cycles are enough to check whether a transition is fireable or not. The proposed fire unit can be implemented by VLSI much more easily than the old one, and can realize fast PN control