Creating a Top-Level Subsystem Module - Creating a Top-Level Subsystem Module - 2026.1 English - UG1483

To generate output from the Vitis Model Composer model the top-level of the model must contain the Vitis Model Composer Hub block. (Described in Vitis Model Composer Hub.) It must also contain a subsystem that encapsulates the application design. To generate output from the subsystem that is instantiated at the top-level of the design, only HLS Library blocks and a limited set of specific Simulink® blocks can appear in the subsystem. The HLS Library blocks define the functions to be compiled for the packaged IP or compiled C++ code. The top-level design can contain other blocks and subsystem modules that serve different purposes, such as simulation. However, you must completely contain the specified subsystem within the primary application.

To create a subsystem from within a model, add one or more blocks to the model canvas. Select the blocks, and make them into a subsystem as follows:

1. Drag and drop blocks onto the model canvas in the Simulink Editor, as explained in Adding Blocks to a Model.
2. Select one or more blocks, and right-click to use the Create Subsystem from Selection command.
3. Name the subsystem. Select the name you want to assign to the generated output application or IP.
4. Double-click the subsystem to open it in the Simulink Editor, and continue the design.

The Explorer bar and Model Browser in Simulink help you navigate your model:

• The Explorer bar lets you move up and down the hierarchy, or back and forth between different views in the Simulink Editor.
• The Model Browser provides a view of the Model Hierarchy. This lets you select and open different levels to quickly move through the hierarchy of the design.