Patent · US Expired

Data processing system and method having an improved arithmetic unit

US4761755A · kind A · utility

108Cited by
24References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 11, 1984
Grant dateAug 2, 1988
Priority date
Expiry dateJul 11, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2207/3856
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A data processing system, wherein the central processing unit has an arithmetic element for processing data in response to machine program instructions and a control store for microcode program storage responsive to the machine instructions for implementing the instruction, has an improved arithmetic unit for enabling higher throughput without substantially increasing hardware cost. The arithmetic unit has a reconfigurable arithmetic logic unit which is controlled in response to both hardware generated data signals and microcode generated data signals. A data string manipulation circuitry provides for aligning data strings for processing by the arithmetic logic unit. Circuitry is provided, responsive to a decoded machine instruction, for generating control signals for configuring the arithmetic unit and for controlling the data string manipulation circuitry. As a result, the number of microcode steps needed to implement particular decimal and string manipulation machine instructions is significantly reduced, thereby saving machine cycles, while the additional hardware cost is very modest.

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