Hi Husson,
Thank you for sharing the screenshot for the error you are seeing. Without looking directly at your model, it is difficult to pinpoint directly the issue. However, given that this is a root outport block connection error, I can conjecture the following:
Your model likely violated one of the rules by muxing the outputs of two different blocks and feeding it directly to the outport. In Simulink, it is not allowed to have the following situation in your model: "A root Output port is connected directly or indirectly to more than one nonvirtual block port".
In order to resolve this problem, you can use one of the following two approaches:
1) Set the diagnostic 'Invalid root Inport/Outport block connection' to 'none', which will cause Simulink to automatically handle this kind of situations by inserting additional blocks. The diagnostic can be found under: Simulation > Model Configuration Parameters > Diagnostics > Model Referencing > Invalid root Inport/Outport block connection.
2) Insert a gain block with value 1 between the Mux and Outport block. This will make sure only one block is directly fed into the Outport.
Hope this helps.
Sincerely,
David
