A.3.3.TR:4.3.1 - Combine continuous evolution with events

When the model mixes continuous evolution and discrete events, state the flow law in each mode, where that flow is permitted, each event’s condition and timing, and its reset relation. A reset specifies which values change and which remain continuous.

For a condition that triggers an immediate event, evolve only to its first occurrence. Stop the continuous segment, apply the event relations, and resume from the resulting state under the applicable law. Process an already-enabled immediate event before advancing time. If the reset enables another immediate event, resolve that event according to the model before resuming flow. Incompatible event relations or an unresolved sequence of instantaneous changes are reasons to return a model or computation limitation.

An event that is merely permitted has a different timing rule: retain the allowed waiting and choice. Where simultaneous events can conflict, supply their joint relation or a justified priority. The thermostat in :5.4 uses mandatory immediate switching and a reset that preserves temperature.