Patent · US Expired

Cam with additional row cells connected to match line

US5491703A · kind A · utility

171Cited by
10References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 29, 1993
Grant dateFeb 13, 1996
Priority date
Expiry dateJun 29, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C15/04
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method of accessing a content addressable memory having a plurality of RAM cells connected in an array of rows and columns, each row having a plurality of cells for storing a data word, at least one additional cell for storing a checking bit and a match line for providing a signal to indicate when a match occurs between an input data word and data stored in a row of cells, which method comprises storing in at least one row of cells a data word in data cells of the row and a checking bit in said at least one additonal cell of the row, the checking bit having a value dependent on the content of the data word in accordance with an error checking system, and controlling a memory accessing system to effect an associate operation by inputting to the columns of cells an input word with an input checking bit dependent on said input word in accordance with the same error checking system, comparing the input word and input checking bit with stored contents of each row of cells and in any row where a mismatch of the input data word with the stored data word occurs causing at least two cells in that row to change a signal level on a match line for that row, said memory accessing system being…

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