Patent · US Expired

Memory having concurrent read and writing from different addresses

US5420997A · kind A · utility

13Cited by
5References
6Claims
0Family size

Inventors

Key dates

Filing dateJan 2, 1992
Grant dateMay 30, 1995
Priority date
Expiry dateJan 2, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/0846
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A random access memory (RAM) complex that can concurrently read and write to different addresses. The memory complex includes two RAMs, each having an address selector, includes a data out multiplexer for selecting outputs from one of the RAM's. A tag array stores an array of tag, one for each address in the RAM's. The tag marks which one of the two RAM's has the valid data for the corresponding read address. During a concurrent read and write cycle, the tag selects the read address for one RAM, selects the write address for the other RAM and a staged copy of the tag controls the multiplexer to select data from the correct RAM for the data out.

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