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11.6 State Hierarchies > 11.6 State Hierarchies - Pg. 296

296 CHAPTER 11 Modeling Event-Based Behavior with State Machines Submachine States A submachine state contains a reference to another state machine that is executed as part of the execution of the submachine state's parent. The entry- and exit-point pseudostates of the referenced state machine are represented on the boundary of the submachine state by special vertices called connection points. Connection points can be the source or target of transitions connected to states outside the submachine state. A transition whose source or target is a connection point forms part of a compound transition that includes the transition to or from the corresponding entry- and exit-point pseudostate in the referenced state machine. An example of this can be seen in Figure 11.14. In any given use of a state machine by a submachine state, only a subset of its entry- and exit-point pseudostates may need to be externally connected. initializing /ccount passed 1; 0; t1 testing : Test Camera [ccount total cameras] fail pass /passed passed 1 /ccount ccount 1 [ccount total cameras]/init OK (passed 0) FIGURE 11.14 Invoking a substate machine.