Engineering systems often share interface definitions across multiple components or subsystems.
Interfaces in System Composer™ can be stored either locally in a model or in a data dictionary, depending on the maturity of your system.
An interface data dictionary is a consolidated list of all the
interfaces in an architecture and where they are used. Local interfaces on a System Composer model can be saved in an interface data dictionary using the Interface Editor.
Interface dictionaries can be reused between models that need to use a given set of interfaces
and interface elements. Data dictionaries are stored in separate .sldd
files.
By default, interfaces are stored within the architecture model and are not visible outside the model. If you are in the initial stages of building a system model, store interfaces locally to limit the number of files that need to be managed. However, if your model is mature to the point of leveraging componentization workflows like reference architectures and behaviors, storing interfaces in a data dictionary gives you the ability to share interface definitions across the model hierarchy.
Use the
menu to save an interface to a new or existing data
dictionary. To create a new data dictionary, select Save to new
dictionary. Provide a dictionary name.

You can also add the interface definitions in the model to an existing data dictionary by selecting Link existing dictionary.
Use the
button to import interface definitions from a Simulink® bus object, either from a MAT-file or the workspace.
Delete an interface from a dictionary using the
button. If the interface is already being used by ports in a
currently open model, the software returns a warning message. The interface is then removed
from any ports in the open model that are associated with the interface. Note that if an
interface is deleted from a dictionary, upon opening another model that shares the dictionary,
a warning will be presented on startup if the deleted interface is used by ports in that
model. The Diagnostic Viewer offers an option to remove the deleted interface from all ports
that are still using it. You can also select ports individually and delete their missing
interfaces.

Note that a System Composer model and a data dictionary are separate artifacts. Even when the data
dictionary is linked to the model, changes to the data dictionary (a .sldd
file) must be saved separately from changes to the model (a .slx file). To
save changes to a linked data dictionary, use the
button and select Save dictionary.
Once a data dictionary is saved, other models can use its interface definitions by linking to
the data dictionary, allowing multiple models to share the same interface definitions.
createDictionary | linkDictionary | openDictionary | saveToDictionary | unlinkDictionary