There are times when the Analyst would like to determine the degree of fault isolation that would be possible if individual signals could be tested at every possible internal location, without having to define a large number of imaginary tests to support this analysis. To facilitate this type of study, eXpress allows the Analyst to generate diagnostics using all of the individual net functions as if they were tests. When selected, the diagnostics will assume that each net function can test every upstreamoutput function and failure mode. Object States are ignored when determining the coverage for each net function (as if all states were enabled). This approach can be utilized to generate diagnostics in which ambiguityis generated only by design feedback loops (as opposed to fan-outs and other features of the design topology).
Tests and net functions can also be utilized together in diagnostics. Refer to the Test Candidate Groupings in the predefined Diagnostic Algorithms to understand how net functions are prioritized for each algorithm (as a rule of thumb, they will not be performed until all useful test set tests have been utilized).
