Patent · US Expired

Dynamic memory controller for single-chip microprocessor

US4649511A · kind A · utility

104Cited by
3References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 25, 1983
Grant dateMar 10, 1987
Priority date
Expiry dateJul 25, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/406
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A controller for interfacing a single-chip microcomputer with external dynamic random-access memory, includes a subcircuit for generating a column-address strobe at a time after a row-address strobe is generated, and also includes a multiplexing subcircuit for providing the proper 8-bit portion of a 16-bit address output from the microprocessor to the 8-bit dynamic memory inputs, prior to receipt of the associated row-address or column-address strobe. The microprocessor utilizes the strobe-generation and multiplexing subcircuits to burst-refresh the dynamic memory, in one presently preferred embodiment. In another presently preferred embodiment, lines from an additional microprocessor output port are utilized with a resettable binary counter and a multiplicity of buffers, to count through the range of row addresses in cyclic fashion, with each address being incremented after the previously-addressed row of memory cells has been refreshed.

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