| Previous | Table of Contents | Next |
A condition space describes a set of conditions; that is, it is a space of conditions. Each condition space is associated
with a particular sub-reason of the main reason ConditionReason. Each condition has logic describing when the condition is
active. The logic is described in a little language having the following constructs:
• arithmetic operators
• logic operators
• references to properties
The referred properties must be included in the set of properties defined by the associated reason. The little language grammar
is server specific and is outside the scope of this specification. Transitions describe what transitions between conditions
are allowed. The interface does not support exploration of the transitions.
In OPC the ConditionSpace interface is implemented by the methods:
• IOPCEventServer::QueryConditionNames()
• IOPCEventServer::QuerySubConditionNames()
.
+conditions
ConditionEvent
(from DAISAEIO)
Figure 5-12 DAIS alarms and events condition space IDL in UML