The role of test protocols in testing embedded-core-based system ICs

A core-based design style introduces new test challenges, which, if not dealt with properly, might defeat the entire purpose of using pre-designed cores. Macro Test is a liberal test approach for core-based designs, i.e., it supports all kinds of test access mechanisms to the embedded cores. The separation of tests into test protocols and test patterns plays a crucial role in Macro Test. Tasks as expansion of core-level tests to chip level, scheduling of tests, and test assembly are carried out on test protocols by software tools. This paper addresses the role of test protocols and features an example of a small scan-testable core. We argue that the fact that expansion and scheduling take place on test protocols rather than on complete tests is important to reduce the computational complexity of the associated software tools.