Hardware Verification

Methods for detecting logical errors in computer hardware designs using symbolic manipulation instead of digital simulation are discussed. A non- procedural register transfer language is proposed that is suitable for describing how a digital circuit should perform. This language can also be used to describe each of the components used in the design. Transformations are presented which should enable the designer to either prove or disprove that the set of interconnected components correctly satisfy the specifications for the overall system. The problem of detecting timing anomalies such as races, hazards, and oscillations is addressed. Also explored are some interesting relationships between the problems of hardware verification and program verification. Finally, the results of using an existing proof checking program on some digital circuits are presented. Although the theorem proving approach is not very efficient for simple circuits, it becomes increasingly attractive as circuits become more complex. This is because the theorem proving approach can use complicated component specifications without reducing them to the gate level.