Arrays are most naturally represented as lists in XML, so in AML, array DataTypes are represented as XML lists. The AML AttributeType Library of an OPC UA Namespace defines a number of lists for arrays of UA DataTypes, of which a subset is shown in Figure A.3. The same pattern shall be used to construct arrays of any derived DataTypes.

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Figure A.3 – Some of the “ListOf” AttributeTypes representing UA array DataTypes

The “ListOf” attributes are all derived from the OrderedListType attributes in the standard AutomationMLBaseAttributeTypeLib.