Patent ID: 7392449

Claim:
Apparatus for performing diagnostics on a scan chain having a plurality of latches, the apparatus comprising: a computer test system comprising means for diagnosing a scan chain employing at least one fuse coupled to at least one latch of the scan chain to load a first logic value into the at least one latch at known location(s) within the scan chain, wherein the at least one fuse couples to the at least one latch at a system port thereof; and wherein the means for diagnosing the scan chain further comprises means for unloading values from the scan chain, and if the scan chain is broken, for localizing a break in the scan chain from the unloaded logic values by comparison thereof with the known location(s) of the at least one latch of the scan chain loaded with the first logic value via the at least one fuse, wherein at least one known location of the known location(s) of the at least one latch is positioned between the break in the scan chain and a scan-out of the scan chain.