Patent · US Expired

Method and apparatus for performing restricted modulo arithmetic

US5249148A · kind A · utility

20Cited by
3References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 26, 1990
Grant dateSep 28, 1993
Priority date
Expiry dateNov 26, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2205/106
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A digital data processor is capable of performing limited modulo arithmetic. The base, M, of the modulo arithmetic to be preformed by the processor must be equal to 2.sup.X, where X is an integer. The method and apparatus is particularly useful for generating addresses for a circular buffer or queue data structure and avoids both the large amount of hardware required for general modulo arithmetic and the software overhead associated with the use of linear arithmetic to generate modulo addresses. According to this method, X is represented as a first digital value. This representation of X is ANDed with a second digital data value (an offset). The result is then ADDed linearly with a third digital data value (a current address with the buffer). During this addition process, certain carry-out signals are inhibited from propagating, according to the digital representation of X.

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