Using Simulink

Tunable Parameters

Many block parameters are tunable. A tunable parameter is a parameter whose value can be changed without recompiling the model (see Model Compilation for more information on compiling a Simulink model). For example, the gain parameter of the Gain block is tunable. You can alter the block's gain while a simulation is running. If a parameter is not tunable and the simulation is running, Simulink disables the dialog box control that sets the parameter.

Note    Simulink does not allow you to change the values of source block parameters through either a dialog box or the Model Explorer while a simulation is running. Opening the dialog box of a source block with tunable parameters causes a running simulation to pause. While the simulation is paused, you can edit the parameter values displayed on the dialog box. However, you must close the dialog box to have the changes take effect and allow the simulation to continue.

It should be pointed out that parameter changes do not immediately occur, but are queued up and then applied at the start of the next time step during model execution. Returning to our example of the constant block, the function it defines is signal(t) = ConstantValue for all time. If we were to allow the constant value to be changed immediately, then the solution at the point in time at which the change occurred would be invalid. Thus we must queue the change for processing at the next time step.

You can use the Inline parameters option on the Optimization pane of the Model Parameter Configuration Dialog Box to specify that all parameters in your model are nontunable except for those that you specify. This can speed up execution of large models and enable generation of faster code from your model. See Model Parameter Configuration Dialog Box for more information.

Block Parameters

Block Sample Times

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