Inport/Output ordering on subsystem reference in parent model

I have a simple subsystem reference model that has 3 inputs and 2 outputs. When referencing the subsystem reference, it was realized that the ports can move within the parent model without affecting the subsystem reference (shown in the image attached). My question is this, is there a way to disallow changing the port order, such that the order would remain in the numbered order of the subsystem reference?

Answer 1

[Swastik Sarkar]

Hi @nmb,

I have encountered a situation where ports can be easily rearranged by dragging, as described in the following documentation:

https://www.mathworks.com/help/simulink/ug/connect-subsystems.html#mw_08d26a15-8a3e-4f56-ac48-742f9044dae0

To prevent reordering in the subsystem reference, ports can be locked by marking Subsystem Reference as ReadOnly, a feature introduced in R2021b. More information about this feature is available here:

https://www.mathworks.com/help/simulink/release-notes.html?startrelease=R2021b&endrelease=R2021b&rntext=&groupby=release&sortby=descending&searchHighlight=#mw_085456b8-4471-4ebc-a24f-b73cdc55389d

As shown in the figure, attempts to modify do not allow rearranging the port.