Table 20defines the ReadEventDetailsstructure. This parameter is only valid for Objectsthat have the EventNotifier Attributeset to TRUE (see OPC 10000-3). Two of the three parameters, numValuesPerNode, startTime, and endTimeshall be specified.
|
Name |
Type |
Description |
|
ReadEventDetails |
Structure |
Specifies the details used to perform an Eventhistory read. |
|
numValuesPerNode |
Counter |
The maximum number of values returned for any Node over the time range. If only one time is specified, the time range shall extend to return this number of values. The default value of 0 indicates that there is no maximum. |
|
startTime |
UtcTime |
Beginning of period to read. The default value of DateTime.MinValueindicates that the startTimeis Unspecified. |
|
endTime |
UtcTime |
End of period to read. The default value of DateTime.MinValueindicates that the endTime is Unspecified. |
|
Filter |
EventFilter |
A filter used by the Server to determine which HistoricalEventNodeshould be included. This parameter shall be specified and at least one EventFieldis required. The EventFilterparameter type is an Extensible parameter type. It is defined and used in the same manner as defined for monitored data items which are specified in OPC 10000-4. This filter also specifies the EventFieldsthat are to be returned as part of the request. |