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:
Sep. 28, 1993
Filed:
Dec. 13, 1991
Applicant:
Inventors:
Assignee:
NCR Corporation, Dayton, OH (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
395425 ; 364D / ; 364243 ; 36424341 ; 364247 ; 3642653 ; 364285 ;
Abstract
A method and system of maintaining coherency for a data block transferred from a main memory to a cache memory. The data transfer is recorded in a tag register in the main memory. An overwrite of the data block is detected by comparing main memory data writes with the recorded transfer. The cache memory is only notified in the event an overwrite is detected. An invalid flag is then set in the cache.