Patent ID: 8473796

Claim:
A method of testing a device under test (DUT) in an automatic test equipment (ATE), comprising the steps of: receiving a first data sequence from the DUT in response to a first stimulus signal, wherein the first stimulus signal is a data sequence for controlling the DUT to provide the first data sequence at a data rate corresponding to a data rate of the first stimulus signal and wherein the first data sequence comprises compressed data of a plurality of internal data sequences; comparing the first data sequence with expected data and detecting at least one error in the first data sequence; and providing a second stimulus signal to the DUT in order to instruct the DUT to generate a second data sequence comprising uncompressed data of the plurality of the internal data sequences at a position or positions wherein the at least one error has been detected, wherein the second stimulus signal stimulus is formed by inserting at least one diagnosis sequence into said data sequence of the first stimulus signal for controlling the DUT, to provide the uncompressed data of the plurality of the internal data sequences at the position or positions wherein the errors have been detected.