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. 02, 1992
Filed:
May. 15, 1989
Applicant:
Inventors:
William B Ledbetter, Jr, Austin, TX (US);
Russell A Reininger, Austin, TX (US);
Assignee:
Motorola, Inc., Schaumberg, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
395425 ; 364D / ;
Abstract
A bus snoop control method for maintaining coherency between a write-back cache and main memory during memory accesses by an alternate bus master. The method and apparatus incorporates an option to source `dirty` or altered data from the write-back cache to the alternate bus master during a memory read operation, and simultaneously invalidate `dirty` or altered data from the write-back cache. The method minimizes the number of cache accesses required to maintain coherency between the cache and main memory during page-out/page-in sequences initiated by the alternate bus master, thereby improving system performance.