Add a trigger to a signal in the Simulation Data Inspector to specify criteria that determine when to update plots to display fresh data. Triggers can allow you to capture transient signal behavior and can help stabilize the display of periodic signals so you can take measurements.

Simulate the Triggers model. Data in the model logs to the Simulation Data Inspector.

open_system('Triggers');
out = sim('Triggers');

Then, add a trigger to the Pulse signal. Configure the trigger as a falling-edge trigger with a threshold of 0.5.

trigRun = Simulink.sdi.getCurrentSimulationRun('Triggers');
pulseSig = getSignalsByName(trigRun,'Pulse');
Simulink.sdi.addTrigger(pulseSig,'Type','Edge','Level',0.5);

You can verify that the trigger was added and configured correctly by opening the Simulation Data Inspector using Simulink.sdi.view and clicking the trigger icon next to the Pulse signal to check the configuration. You can also use the Simulink.sdi.getTrigger function to check which signal is used to generate trigger events and the trigger configuration.

[sig,trigOpts] = Simulink.sdi.getTrigger;

sig.Name

ans = 
'Pulse'

trigOpts

trigOpts = struct with fields:
                       Mode: 'Auto'
                       Type: 'Edge'
                   Position: 0.5000
                      Delay: 0
    SourceChannelComplexity: 'Scalar'
                   Polarity: 'Positive'
                  AutoLevel: 1
                      Level: 0.5000
                 UpperLevel: 0
                 LowerLevel: 0
                 Hysteresis: 0
                    MinTime: 0
                    MaxTime: Inf
                    Timeout: 0
                    Holdoff: 0

When you do not want to use a trigger to control when the Simulation Data Inspector updates the plots with fresh data, you can remove the trigger using the Simulink.sdi.removeTrigger function.

Simulink.sdi.removeTrigger

You can verify that the trigger was removed in the Simulation Data Inspector UI or using the Simulink.sdi.getTrigger function. The Simulink.sdi.getTrigger function returns an empty array of Simulink.sdi.Signal objects when no trigger is configured in the Simulation Data Inspector.

sig = Simulink.sdi.getTrigger;
size(sig)

ans = 1×2

     0     0