Because Operational tests are path-based tests, coverage and stimuli are automatically determined using knowledge from the functional model. The test coverage is initially filled out with all output functions in the design that are upstream from the specified measurement location and which are not omitted due to the test's state selections. Likewise, the test's stimuli are filled out with all input flags and connectors that are upstream from the specified measurement location.
Operational tests are the only type of eXpress tests that are inherently symmetric, meaning that the same functions are exonerated when the test passes as those that are indicted when the test fails. Because of this, they can be thought of as the most diagnostically efficient type of eXpress test. For more details on test symmetry for Operational tests, refer to the topic "Operational Tests - Symmetry Explained".
When an Operational test is inherited hierarchically, the test will be performed at an upper-level test location and the stimuli consists of inputs to the upper-level model. Additional upper-level coverage will be added to the hierarchical test (both upstream and downstream from the inherited coverage) based on the new test location and stimuli.
