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:
Jan. 14, 1997
Filed:
Nov. 01, 1994
Masataka Osaka, Osaka, JP;
Matsushita Electric Inductrial Co., Ltd., Osaka, JP;
Abstract
In a system bus connected to at least one CPU having a cache memory used for increasing memory access speed in an engineering workstation or the like, a main memory controller including a status memory for storing owned and unowned statuses in a main memory and a cache memory of data associated with an access operation to a system bus connected to at least one CPU having a cache memory performed by an access means of a CPU or the like, a memory control portion which is responsive to signals indicative of the stored statuses for reading the data in the main memory before the time for outputting a data invalidating signal from the cache memory elapses in the case of the owned status and for reading the data in the cache memory after the data invalidating signal is output in the case of the unowned status, and a status rewrite control portion for monitoring accesses to the system bus and for rewriting the status in the status memory according to the result of the monitoring.