All path-based tests in eXpress have a location for testing and a list of stimuli. The stimuli represent those inputs that directly influence the results of the test. Although nearly every input may be required to get a valid test result, the test stimuli in eXpress are specifically used to refine the path and in turn, the coverage of the test. This allows the diagnostics to interpret the test more accurately, proving good only those output functions or failure modes that are truly evaluated by the test.
Different types of test use the stimuli list slightly differently. For User-Initiated and Probe tests, the stimuli can be added and removed in order to control the paths that create the coverage. For Signature tests, stimuli are displayed for information purposes (since the test already has the coverage specified explicitly) to help the Analyst envision the creation interference that may be introduced for that test. Inspection tests do not use stimuli at all, since they are independent from the design's topology.
Therefore, it is best to examine how each test is used by the diagnostics in order to determine how to properly control the stimuli.
