This EventType is defined in OPC 10000-3. Its representation in the AddressSpace is formally defined in Table 47.

Table 47 – AuditWriteUpdateEventType definition

Attribute		Value
BrowseName		AuditWriteUpdateEventType
IsAbstract		True
References	NodeClass		BrowseName	DataType	TypeDefinition	ModellingRule
Subtype of the AuditUpdateEventType defined in 6.4.24, which means it inherits the InstanceDeclarations of that Node.
HasProperty	Variable		AttributeId	UInt32	PropertyType	Mandatory
HasProperty	Variable		IndexRange	NumericRange	PropertyType	Mandatory
HasProperty	Variable		NewValue	BaseDataType	PropertyType	Mandatory
HasProperty	Variable		OldValue	BaseDataType	PropertyType	Mandatory
Conformance Units
Auditing Write

This EventType inherits all Properties of the AuditUpdateEventType. The SourceName for Events of this type shall be "Attribute/Write". Their semantic is defined in 6.4.24.

AttributeId identifies the Attribute that was written. The SourceNode Property identifies the Node that was written.

IndexRange identifies the index range of the written Attribute if the Attribute is an array. If the Attribute is not an array or the whole array was written, the IndexRange is set to null.

NewValue identifies the value that was written. If the IndexRange is provided, only the values in the provided range are shown.

OldValue identifies the value that the Attribute contained before the write. If the IndexRange is provided, only the value of that range is shown. It is acceptable for a Server that does not have this information to report a null value.

Both the NewValue and the OldValue will contain a value in the DataType and encoding used for writing the value.