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Using Triggers

Contents

To create a Trigger:

2.Right-click in the Signal Plot Area, then select DataBlock->Properties, or right-click on the red DataBlock bar then select "Properties" from the context menu.

DataBlock-Triggers

3.Select the Triggers tab.

4.Use the Add, Edit, or Remove buttons to create, change, or delete a Trigger.

5.Enter a name and description of the Trigger. (optional)

6.Set the Trigger Condition and Trigger Action.

7.Click OK.

The trigger is marked in the TestCase with a green arrow:

A trigger in the second DataBlock of a Signal

Trigger Condition

There are three options for Trigger Condition:

•Change - The trigger is fired when the specified transition occurs (as shown in the example below). When counting transitions, it may be helpful to view the Transition List with the ID box checked. However, note that only transitions in the current DataBlock are counted.

•Failure - The trigger is fired when a failure is detected on-the-fly. The Project Setting for Pass/Fail Analysis must be set to On-the-Fly; see Project Settings.

•Threshold - The trigger is fired when the value of the Signal meets the specified condition relative to the specified Threshold. Options are: greater than, less than, less than or equal to, greater than or equal to, or equal. Note that if you are using a continuous Signal it may not be possible to meet the equal condition, so <= or >= are recommended.

TriggerExecution

Trigger Action

There are three tabs to specify the Trigger Action. All triggers, regardless of the specified action, can be used in Relative Time Criteria.

Execution

The Execution tab offers these options for the trigger action:

•None - The trigger fires but execution continues. The pass/fail analysis may be affected by options selected on the Pass/Fail Judgment tab.

•Set TestCase Complete - Execution of the TestCase is terminated when the trigger is fired.

•Set Scenario Complete - Execution of the TestCase and Scenario is terminated when the trigger is fired.

•Assert Failure - When this option is selected, you must also select a Signal from the drop-down list below it. The selected Signal is marked as Failed when the trigger fires.

TriggerExecution

Pass/Fail Judgment

These options are available on the Pass/Fail Judgment tab:

•No Action - Normal pass/fail analysis is performed. It is not changed by the trigger.

•Assert Failure when Trigger occurs - The Signal that contains the DataBlock is marked Failed when the trigger fires.

•Assert Failure if Trigger does not occur - The Signal that contains the DataBlock is marked Failed if the trigger does not fire during TestCase execution.

•Force to Pass when Trigger occurs - The Signal that contains the DataBlock is marked Passed when the trigger fires. This overrides any failures detected in normal pass/fail analysis.

TriggerPassFail

Note: Since pass/fail analysis is performed on responses only, this tab is not available for Stimulus Signals.

Shell Command

Check the Enable box in the Shell Command tab to execute the command in the Executable File text box when the trigger is fired.

TriggerShell

You can use this feature to interface with other test tools. It's also useful for safety functions. For example, you could set up a trigger and shell command to shut down the test if the temperature exceeds 100 degrees Celsius.

Example: Relative Time Criterion

Suppose we want to ensure that the time between two Trigger points is correct (this is called a Relative Time Criterion). Consider the image below:

TriggerEx1

Lets define the first Trigger point as the last pulse in the second sequence of five pulses. We select the second sequence of five pulses and convert it to a DataBlock. Now go into the DataBlock properties:

triggerEx2

In the example above, we have defined a Trigger as follows:

•The Trigger point is the 10th transition in the second DataBlock (2 transitions for each pulse)

•No action will be taken when this Trigger fires

Specify a second Trigger on another Signal in the same TestCase. Again, no action is to be taken when the Trigger fires.

Then go to the TestCase Properties to specify the Relative Time Criterion.

Triggers and System Signals

Triggers do not work directly with System Signals. However, triggers can be set on probes. To set a trigger on a System Signal, probe it then assign the trigger to the probe.

Using Triggers

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