The Attributes of Nodes, their DataTypes and descriptions are defined in OPC 10000-3. Attributes not marked as optional are mandatory and shall be provided by a Server. The following tables define if the Attribute value is defined by this specification or if they vendor specific.
For all Nodes specified in this specification, the Attributes named in Table 3 shall be set as specified in the table.
Table 3 – Common Node Attributes
|
Attribute |
Value |
|
DisplayName |
The DisplayName is a LocalizedText. Each server shall provide the DisplayName identical to the BrowseName of the Node for the LocaleId “en”. Whether the server provides translated names for other LocaleIds is vendor specific. |
|
Description |
Optionally a vendor specific description is provided |
|
NodeClass |
|
|
NodeId |
The NodeId is described by BrowseNames as defined in 3.4.2.1 and defined in Annex A. |
|
WriteMask |
Optionally the WriteMask Attribute can be provided. If the WriteMask Attribute is provided, it shall set all Attributes to not writeable that are not said to be vendor-specific like Description, EventNotifier or DisplayName with a LocaleId other than ‘en’. For example, the Description Attribute may be set to writeable since a Server may provide a server-specific description for the Node. The Attributes NodeId, BrowseName and NodeClass and DataType shall not be writeable, because they are defined for each Node in this specification. The WriteMask Attribute does not take any user access rights into account, that is, although an Attribute is writeable this may be restricted to a certain user / user group. |
|
UserWriteMask |
Optionally the UserWriteMask Attribute can be provided. It takes the user access rights for the Session user into account. |