The cross-reference list is created from cross-reference objects (*.SCT) which are first created separately for each POU tested from a list of global variables (GVLs) and from each data unit type (DUT). These cross-reference objects are then linked by the system to create a cross-reference file (*.SCX).
Cross-reference objects for the cross-reference list are only created if you have checked the objects (POUs, GVLs, DUTs) or the whole project with and activated the option to generate cross-reference objects during the check/compile process under . During each check of an object, the accompanying cross-reference object is updated.
By checking “Link cross-reference objects to cross-reference list”, you can have the cross-reference list created automatically while compiling the program. As this makes the compilation procedure longer, we do not recommend this procedure.