To run your model in simulation prior to running it on OpenECU target hardware select Start from the Simulation menu, or click on the button in the Simulink toolbar. If your model has no design errors in it, and Simulink can find all the resources it needs, the simulation will run.

Of course, for this example, you cannot change the behaviour of the simulation as it runs. In order to do this, you can replace the ground input to the pai_AnalogInput block with a signal generator and attach scopes to the signals to view during the simulation.