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:
Dec. 12, 1995
Filed:
Apr. 06, 1992
Hitachi, Ltd., , US;
Abstract
A memory control unit connected to a scalar processor having a buffer for storing a copy of block data of a main storage and a vector processor having a store requester for writing data into the main storage is disclosed. The memory control unit has a block valid memory having a one-bit valid bit for all blocks. The valid bit represents that the copy of the block data corresponding to said bit is in the buffer of the scalar processor. The memory control unit further has a block group valid table which has a block group bit for each block group. The block group bit represents whether any one of the block valid bits of the block belonging to the corresponding group is valid or not. When the vector processor stores the data into the main storage by the store requester, the memory control unit first searches the block group valid table to check whether the block group valid bit of the block group including the store address is valid or not. If it is valid, the memory control unit further searches the block valid memory to check whether the block valid bit of the block including the store address is valid or not. If it is valid, it invalidates the buffer of the scalar processor.