An Abstract Model for Digital System Fault Diagnosis

An abstract model applicable to the use of both diagnostic programs and hardware diagnostic aids in digital systems is presented. The model is capable of dealing with replaceable units having a variety of complexity and is shown in a mathematically rigorous fashion to encompass existing models for diagnosis. A three-level structure for representing faults and a two-level structure for representing tests are employed. Faults, multiple faults, tests, and test results are represented by sets. Relationships between these entities are represented by binary relations and functions.