Tag database version

The ABCIP Communication Driver periodically checks for version changes and uploads the journal information from the controller, so that the tag database it maintains matches the corresponding database in the controller.

You can monitor changes in the Logix tag database version by subscribing to the tag database system item $SYS$TagDBVersion at the hierarchy of any CompactLogix, FlexLogix, or ControlLogix controller.

The ABCIP Communication Driver shows the new database major and minor versions presented as a number in addition to uploading the journal information from the controller.

Note: For tag items defined as array data types in an item addition request, the OPC_E_BADTYPE error is returned when an OPC client does not specify the array data type or the VT_EMPTY data type. The only exception is when an OPC client specifies VT_BSTR as the requested data type for an item that is defined as VT_ARRAY|VT_UI1. In this case, the Communication Driver accepts the item addition and returns the data as VT_BSTR.