Patent · US Expired

Cache memory apparatus having a plurality of accessibility ports

US5274790A · kind A · utility

60Cited by
2References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 30, 1991
Grant dateDec 28, 1993
Priority date
Expiry dateApr 30, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/126
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A cache memory apparatus to be coupled to a main memory, comprises a cache memory having a plurality of ports and capable of being independently accessed through the plurality of ports. The cache memory stores a portion of data stored in the main memory and tag information indicating memory locations within the main memory of the data portion stored in the cache memory. A hit discriminator receives first tag information included in an address given when the cache memory is accessed and second tag information read from the cache memory in accordance with the given address, in order to discriminate a cache-hitting and a cache-missing on the basis of the first and second tag information. A replacement control circuit operates for replacing data and corresponding tag information in the cache memory when the cache-missing is discriminated by the hit discriminating circuit. A replacement limiting circuit operates for limiting the replacement of the cache memory to one time when a plurality of accesses to the same address are generated and all the plurality of accesses to the same address are missed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.