Figure 14 shows the “Parameters” sub-aspect in the Functional Aspect of the Information Model.
Figure 14 – Parameters Organization
The GsdGenParameterVariableType Variable represents one Parameter as part of a parameter record described by the “ParameterRecordDataItem” element in the GSDML. Each GsdGenParameterVariableType Variable shall be part of the “Configuration” folder. The optional Index Property contains the PROFINET record number used to read the parameter record from the Device. The “Configuration” folder Object references as many GsdGenParameterVariableType Variables as there are separate Parameter values in the Parameter records referenced by the associated Submodule. The modelling of the Parameters as Variables allows Clients to obtain the Parameters without dissecting the Parameter record structure. Figure 15 shows the schema of the GSDML “ParameterRecordDataItem” elements describing Parameter records.
Figure 15 – XML Schema of ParameterRecordDataItem elements
The Server shall use the “Index” attribute of the “ParameterRecordDataItem” element to read the actual value of the parameter record from the Device. The Server shall then use the attributes of the “Ref” elements describing single Parameters to obtain the values needed to create the GsdGenParameterVariableType Variables.
Only Parameters described by “ParameterRecordDataItem” elements contained in the “ApplicationProcess/RecordDataList” shall be represented in the Information Model. These “ParameterRecordDataItem” elements are referenced by “(Virtual)SubmoduleItem /RecordDataList/ParameterRecordDataRef” elements (see Figure 16 and [GSDML], 8.15.9).
Figure 16 – RecordDataList child element schema
Since only Parameter records readable from the Submodule are allowed (see above), the referenced “ParameterRecordDataItem” elements shall have an “Access” attribute containing at least the “prm” and the “read” tokens. Elements describing Parameter records which cannot be read from the Submodule shall not be referenced.
Figure 17 shows the mapping of the “ParameterRecordDataItem” elements and their “Ref” child elements to Variables and Properties in the Information Model. The “Const”, “MenuList”, “RefMeta” and “RecordMeta” elements are not used as well as most attributes of the “Ref” element.
Figure 17 – Mapping of XML elements describing configuration data
The Server shall provide the “Configuration” folder Object only if there are readable Parameter records specified in the GSDML for the Submodule.