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A b t ractThis paper proposes a new programmable controller baaed on the usage of Petri Net to describe the status of a whole syrtem. The proposed programmable controller consists of Fire Unit and Input Handling Unit. And it does not UM MY processon, because pluea u p r e~ the status of the controller, not proasses. Fin Unit L an ASIC memory with very wide word to check whether a transition is fireable or not in two memory cycles. Since Input Handling Unit can choose the earliest arrival signal input using mutual exclusion rule, it is not necessary to scan d input. It takes only Cour memory cyclu, Cor the newly proposed system to process one input signal. So it is possible to realize much Cuter control that the conventional system and it has mathematically analyzable foundation.

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faster control than conventional systems. Since Petri NetWe have proposed a high speed Petri Net Sequence Controller[l] which controls systems described in Petri Net. The main function ofits hardware architecture can be implemented in one-chip ASIC memorj-. But it is difficult to make ASIC for large Petri Net because of t h e restriction to the number of ASIC chip pins.To reduce 1/0 pins for one chip Petri Net Controller, we propose division strategy from a large Petri Net to several smaller subnets and an architecture of new Petri Net Controller with special 1/0 interface to handle with tokens between subnets. And We show that Petri Net Controller for large Petri Net can be constructed by smaller new Petri Net Controllers for sub.nets.