Symbol Interface

The Symbol Interface block provides a graphical user interface (UI) for browsing ADS symbols. It simplifies the selection of different ADS symbols as read or write symbols and the parameterization of the symbols. The block creates, based on the configuration created by the user, a LabVIEW™ string which can be passed to the Init VI. Likewise, an XML file of the created configuration can be saved from the UI so that the configuration can be loaded and passed to the Init VI without repeated manual configuration.

Microsoft Windows only The Symbol Interface block can be accessed only with a Windows operating system.

Running the Symbol Interface will open the graphical user interface shown below. The TwinCAT Target Browser is integrated in the middle part. This is used to browse target systems or their ADS symbols. By drag and drop an ADS symbol (or by multi-select several ADS symbols at the same time) can be dragged to the right area for read accesses or to the left area for write accesses. For each selected ADS symbol a graphic element appears in the Write or Read area. By double-clicking on these graphical elements (multi-select is also possible here) another window appears. The window describes the information of the ADS symbol and offers the option to attach parameters to the ADS symbol, which are used for certain read or write commands.

Manual addressing via AmsNetId, Port, Index Group and Index Offset is also possible. To do this, create a new element under ADS-Read or ADS-Write with New and you can fill in the "Symbol Info" area manually.

Paramater CycleTime The cycle time in which the selected ADS symbol is executed in the TwinCAT runtime is always offered as the default value for the CycleTime. Only multiples of this cycle time are allowed, since an ADS notification with the new value is sent after each completed cycle. If a value other than CycleTime is entered, it is always rounded up to the next permissible value.