Enter actions of a state are written under the ENTER descriptor. Exit actions are written under the EXIT descriptor. There are two obligatory properties and one optional property for enter actions and exit actions:
There may be multiple parts of enter/exit actions defined for a single state. This is done with multiple ENTER or EXIT descriptors with the same N or S property. The guards of those parts are mutually independent. Each guard only controls the execution of the actions under one descriptor.
The model with an enter action and an exit action in Figure 4.11 is translated into the textual representation in Table 4.9.