· It is a graphical modeling tool suggested by C A Petri
· Used in designing the algorithms for control circuits, computational and communication operators
· FSM is used when there are finite number of states and petri nets are used when the number of states is definite
· Instead of the states of the FSM model, there are the node-places and node-Transitions at each net.
· A circle shows the Node-places and a rectangle shows the Node-Transition.
· The node-place describes the state and the Node Transition describes the computations and Actions
· Each entry point or initial node place is indicated by a dot in the centre of the node place and is called the masking place.
Timer Using Petri Net