3 Terms, definitions and conventions ToC Previous Next

3.4 Conventions used in this document ToC Previous Next

3.4.1 Conventions for Node descriptions ToC Previous Next

Node definitions are specified using tables (see Table 2).

Attributes are defined by providing the Attribute name and a value, or a description of the value.

References are defined by providing the ReferenceType name, the BrowseName of the TargetNode and its NodeClass.

  • If the TargetNode is a component of the Node being defined in the table the Attributes of the composed Node are defined in the same row of the table.
  • The DataType is only specified for Variables; “[<number>]” indicates a single-dimensional array, for multi-dimensional arrays the expression is repeated for each dimension (e.g. [2][3] for a two-dimensional array). For all arrays the ArrayDimensions is set as identified by <number> values. If no <number> is set, the corresponding dimension is set to 0, indicating an unknown size. If no number is provided at all the ArrayDimensions can be omitted. If no brackets are provided, it identifies a scalar DataType and the ValueRank is set to the corresponding value (see OPC 10000-3). In addition, ArrayDimensions is set to null or is omitted. If it can be Any or ScalarOrOneDimension, the value is put into “{<value>}”, so either “{Any}” or “{ScalarOrOneDimension}” and the ValueRank is set to the corresponding value (see OPC 10000-3) and the ArrayDimensions is set to null or is omitted. Examples are given in Table 1.
Notation DataType ValueRank ArrayDimensions Description
Int32 Int32 -1 omitted or null A scalar Int32.
Int32[] Int32 1 omitted or {0} Single-dimensional array of Int32 with an unknown size.
Int32[][] Int32 2 omitted or {0,0} Two-dimensional array of Int32 with unknown sizes for both dimensions.
Int32[3][] Int32 2 {3,0} Two-dimensional array of Int32 with a size of 3 for the first dimension and an unknown size for the second dimension.
Int32[5][3] Int32 2 {5,3} Two-dimensional array of Int32 with a size of 5 for the first dimension and a size of 3 for the second dimension.
Int32{Any} Int32 -2 omitted or null An Int32 where it is unknown if it is scalar or array with any number of dimensions.
Int32{ScalarOrOneDimension} Int32 -3 omitted or null An Int32 where it is either a single-dimensional array or a scalar.

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