Patent ID: 6574764
Filing Date: 2003-06-03
Classification: G11C

Abstract:
A method of preserving the value of a parameter associated with testing a Device Under Test (DUT), the method comprising the steps of:(a) executing in a program execution environment a test program that causes stimulus signal values to be dispatched to a DUT through a stimulus pipeline having a first number of stages; (b) sending from the DUT to the program execution environment, and through a response pipeline having a second number of stages, response signal values obtained by operating the DUT with the dispatched stimulus signal values; (c) for each execution cycle of the test program and from a selected location in one of the stimulus and response pipelines, storing in a History FIFO the value of the parameter that is to be retrieved; (d) generating an error signal within the response pipeline, including at the DUT, in response to a selected error condition; (e) adjusting the depth of the History FIFO to correspond to the number of pipeline stages separating the storing in step (c) and the generation of an associated instance of the error signal in step (d); and (f) in response to an error signal generated by step (d), preserving in the History FIFO the parameter value stored at the depth adjusted to at step (e).