'In system' transparent autodiagnostics of RAMs

摘要

In this paper we present an original technique of testing classical RAMs (without BIST) in real system environment. The developed testing methodology allows to cover a large class of faults including pattern sensitivity and dynamic faults. An important feature of the presented approach is test transparency which assures that at the end of the test the contents of the RAM are equal to its initial contents (before testing). This technique is especially useful for periodic autodiagnostic procedures in embedded and multiprocessor systems. It has been also extended for cache and dual port RAMs.