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:
Jun. 07, 1994
Filed:
May. 01, 1991
Applicant:
Inventor:
Bahador Rastegar, Dallas, TX (US);
Assignee:
SGS-Thomson Microelectronics, Inc., Carrollton, TX (US);
Primary Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
395425 ; 36523005 ; 364D / ;
Abstract
A control circuit for a dual port cache tag memory is used to reset a snoop valid bit for an entry addressed through one of the dual ports. This port snoops a main memory bus, and a cache tag hit which occurs during a write operation to the main memory bus indicates that the snoop valid bit for the addressed entry should be reset. In order to avoid errors in resetting the snoop valid bit, which errors can occur due to signal propagation delay, the control circuit resets the snoop valid bit only after a preselected internal delay period.