Patent · US Expired

Arithmetic logic unit

US5081607A · kind A · utility

8Cited by
4References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 23, 1990
Grant dateJan 14, 1992
Priority date
Expiry dateFeb 23, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2207/3828
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A digital arithmetic logic unit in which the carry chain is subdivided into a series of bit fields allowing independent and simultaneous data manipulation to be undertaken in each of the bit fields. Division of the carry chain is achieved via a carry chain selector consisting of a series of multiplexers, one being placed between each pair of adjacent stages of the carry chain. Each multiplexer has two data inputs, one of which forms the carry to the next stage of the carry chain. The carry selected either continues the computation or defines the end of one bit field and provides the least significant carry-in bit to the next bit field. This selection of the carry by the multiplexer is under control of a programmable register, thus allowing variable division of the carry chain.

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