GlobalConstants (GVL)

This constant can be used for the initialization of not used inputs of type CB_CALLBACK

InOut:

Scope	Name	Type	Initial
Constant	gc_cbNULL	CB_CALLBACK	STRUCT(pPOUFunc := CAA.gc_pNULL, eEvent := EVENT.NO_EVENT, eClass := EVENT_CLASS.NO_CLASS, eSource := EVENT_SOURCE.NO_SOURCE)