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:
May. 24, 2005
Filed:
Jul. 17, 2001
Charles P. Ryan, Phoenix, AZ (US);
William A. Shelly, Phoenix, AZ (US);
Stephen A. Schuerich, Phoenix, AZ (US);
Charles P. Ryan, Phoenix, AZ (US);
William A. Shelly, Phoenix, AZ (US);
Stephen A. Schuerich, Phoenix, AZ (US);
Bull HN Information Systems Inc., Billerica, MA (US);
Abstract
Cache memory, and thus computer system, reliability is increased by duplicating cache tag entries. Each cache tag has a primary entry and a duplicate entry. Then, when cache tags are associatively searched, both the primary and the duplicate entry are compared to the search value. At the same time, they are also parity checked and compared against each other. If a match is made on either the primary entry or the duplicate entry, and that entry does not have a parity error, a cache 'hit' is indicated. All single bit cache tag parity errors are detected and compensated for. Almost all multiple bit cache tag parity errors are detected.