The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 21, 2012
Filed:
Apr. 14, 2009
Michael S. Floyd, Austin, TX (US);
Joshua D. Friedrich, Austin, TX (US);
Robert B. Gass, Pflugerville, TX (US);
Norman K. James, Liberty Hill, TX (US);
Michael S. Floyd, Austin, TX (US);
Joshua D. Friedrich, Austin, TX (US);
Robert B. Gass, Pflugerville, TX (US);
Norman K. James, Liberty Hill, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A mechanism is provided for internally controlling and enhancing logic built-in self test in a multiple core microprocessor. The control core may use architectural support for scan and external scan communication (XSCOM) to independently test the other cores while adjusting their frequency and/or voltage. A program loaded onto the control core may adjust the frequency and configure the LBIST to run on each of the cores under test. Once LBIST has completed on a core under test, the control core's program may evaluate the results and decide a next test to run for that core. For isolating failing latch positions, the control core may iteratively configure the LBIST mask and sequence registers on the core under test to determine the location of the failing latch. The control core may control the LBIST stump masks to isolate the failure to a particular latch scan ring and then position within that ring.