Follow these rules when defining structures in Stateflow® charts:
You must define each structure as a
Simulink.Bus object in the base
You cannot define structures for Stateflow machines.
The Stateflow machine is the object that contains all other Stateflow objects in a Simulink® model (see Stateflow Hierarchy of Objects).
Structures cannot have a constant scope.
Structures of parameter scope must be tunable.
Data array objects cannot contain structures.