On combining off-line BIST and on-line control flow checking

If offline testing is complemented by online checks, in general some of the test hardware is only used either for online checking or for testing. A novel target structure for self-testable and self-monitoring controllers is presented, and a formal framework for the synthesis of self-monitoring controllers is established. It combines a method of monitoring the control flow with a self-test structure in such a way, that the self-test hardware is utilized for facilitating control flow checking. The corresponding design procedure considers this target structure while synthesizing the controller from a behavioral description, and thus minimizes hardware overheads. Existing approaches for designing concurrently checked controllers can be represented as special cases in the formal framework established. Experimental results are summarized.<>