Abstract: A system for at-functional-clock-speed continuous scan array built-in self testing (ABIST) of multiport memory is disclosed. During ABIST testing, functional addressing latches from a first port are used as shadow latches for a second port's addressing latches. The arrangement reduces the amount of test-only hardware on a chip and reduces the need to write complex testing software. Higher level functions may be inserted between the shadow latches and the addressing latches to automatically provide functions such as inversions.

Abstract: An improved method and process of verifying a digital logic design complies with certain manufacturing test rules or guidelines to ensure adequate manufacturing test data can be generated. A replacement is created for any portion of a design to make it usable by the manufacturing test tool set, without requiring the contents of that portion of the design to be implemented. The inputs and outputs of a portion of the design are examined for violations of the manufacturing test rules or guidelines. If there are no violations, the contents of this portion of the design are replaced with some basic contents which satisfy the manufacturing structure rules. The interconnections between logic blocks can then be tested using test generation tools to ensure the design does not violate manufacturing test rules or guidelines The compliance verification can thus be done much earlier in the design process than typically occurs.