Trigger

• Inhibitors (arcs terminated with a hollow circle) provide a means to disable transitions even if there are enough tokens in its input place to enable transition otherwise. They provide an additional control for transition firing. In the presence of inhibitors, a transition is enabled only if for each of the inhibitors that terminate at the transition, the multiplicity of that inhibitor exceeds the number of tokens in its respective place where the inhibitor originates.
• Enablers (arcs terminated with a filled circle) are "inverse inhibitors": a transition is enabled only if the number of tokens in the place where the enabler originates exceeds its multiplicity. Enablers can be modeled using inhibitors (by inhibiting comlementary places with respect to all possbile places where the token or tokens might reside) but enablers can be more effective in providing "AND" logic, especially if there are more than one complementary place (simply by providing enablers for each additional condition that is required to be satisfied to enable the transition). Note, however that only one token (from the input place) is actually fired. If other tokens need to be moved as well (which is not always the case) appropriate additional transitions are added. The use of joints Joints provides a more appropriate means to model the "AND" logic in this scenario.
• Triggers can be hidden from top view if their importance is not deemed critical for the top view (the detailed view is not affected).
• Triggers properties can be controlled from the global list of trigger parameters, found in the menu under the Parameters menu as shown. This global table of parameters can be updated from a linked file as described in Global Parameters Section.