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:
Apr. 10, 2007
Filed:
Mar. 18, 2004
Takuji Kawamoto, Nagoya, JP;
Takuji Kawamoto, Nagoya, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A data memory cache unit is provided which is capable of heightening the speed of memory access. The cache unitexecutes reading and writing of data in a 16-byte width line unit in a main memory unit, executes reading and writing of data in an MPUin the unit of a four-byte width small area included in each line. When the MPUexecutes a push instruction, if a cache miss takes place on a line which includes a small area that holds data which should be read out to the MPU(NO at S), then the cache unitopens the line (S). If a small area into which the data sent from the MPUshould be written is adjacent to a line boundary on the side where an address is larger or on the side where write-in is earlier executed (YES at S), then the cache unitdoes not execute a refill, and if this small area is not adjacent to the line boundary (NO at S), then it executes a refill (S).