The SubscribedDataSetoption TargetVariablesdefines a list of Variablemappings between received DataSetfields and target Variablesin the Subscriber AddressSpace. The FieldTargetDataTypeis defined in 6.2.9.2.3. Target Variablesshall only be used once within the same TargetVariableslist.
This Structure DataTypeis used to represent TargetVariablesspecific parameters. It is a subtype of the SubscribedDataSetDataTypedefined in 6.2.9.1.
The TargetVariablesDataTypeis formally defined in Table 43.
Table 43– TargetVariablesDataType Structure
|
Name |
Type |
Description |
|
TargetVariablesDataType |
Structure |
|
|
targetVariables |
FieldTargetDataType[] |
Defined in 6.2.9.2.1. |
This DataTypeis used to provide the metadata for the relation between a field in a DataSetMessageand a target Variablein a DataSetReader. The FieldTargetDataTypeis formally defined in Table 44.
Table 44– FieldTargetDataType Structure
|
Name |
Type |
Description |
|
FieldTargetDataType |
Structure |
|
|
dataSetFieldId |
Guid |
The unique ID of the field in the DataSet. The fields and their unique IDs are defined in the DataSetMetaData Structure. |
|
receiverIndexRange |
NumericRange |
Index range used to extract parts of an array out of the received data. It is used to identify a single element of an array, or a single range of indexes for arrays for the received DataSetfield. If a range of elements is specified, the values are returned as a composite. The first element is identified by index 0 (zero). The NumericRangetype is defined in OPC 10000-4. This parameter is null if the specified Attribute is not an array. However, if the specified Attribute is an array, and this parameter is null, then the complete array is used. The resulting data array size of this NumericRangeshall match the resulting data array size of the writeIndexRange NumericRangesetting. |
|
targetNodeId |
NodeId |
The NodeIdof the Variablewhere to write the received DataSetMessagefield value to. |
|
attributeId |
IntegerId |
Id of the Attributeto write e.g. the Value Attribute. This shall be a valid AttributeId. The Attributes are defined in OPC 10000-3. The IntegerId DataType is defined in OPC 10000-4. The IntegerIdsfor the Attributesare defined in OPC 10000-6. |
|
writeIndexRange |
NumericRange |
The index range used for writing received data to the target node. It is used to identify a single element of an array, or a single range of indexes for arrays for the write operation to the target Node. If a range of elements is specified, the values are written as a composite. The first element is identified by index 0 (zero). The NumericRangetype is defined in OPC 10000-4. This parameter is null if the specified Attributeis not an array. However, if the specified Attributeis an array, and this parameter is null, then the complete array is used. |
|
overrideValueHandling |
OverrideValueHandling |
The value is used to define the override value handling behaviour if the State of the DataSetReaderis not Operational_2 or if the corresponding field in the DataSetcontains a Bad StatusCode. The handling of the OverrideValuein different scenarios is defined in 6.2.10. The OverrideValueHandlingenumeration DataTypeis defined in 6.2.9.2.4. |
|
overrideValue |
Variant |
This value is used if the OverrideValueHandling is set to OverrideValue_2and the State of the DataSetReaderis not Operational_2 or if the corresponding field in the DataSetcontains a Bad StatusCode. The handling of the OverrideValuein different scenarios is defined in 6.2.10. |
The OverrideValueHandlingis an enumeration that specifies the possible options for the handling of Override values. The possible enumeration values are described in Table 45.
Table 45– OverrideValueHandling Values
|
Value |
Description |
|
Disabled_0 |
The override value handling is disabled. |
|
LastUsableValue_1 |
In the case of an error, the last usable value is used. If no last useable value is available, the default value for the data type is used. |
|
OverrideValue_2 |
In the case of an error, the configured override value is used. |