Patent · US Active

Decimal adder with end around carry

US8554822B2 · kind B2 · utility

6Cited by

3References

18Claims

0Family size

Assignee

International Business Machines Corporation · US

Inventors

Steven R. Carlough · Poughkeepsie, US
Adam B. Collura · Hopewell Junction, US
Klaus M. Kroener · Ehningen, DE
Silvia M. Mueller · Altdorf, DE

Key dates

Filing date	Jun 24, 2010
Grant date	Oct 8, 2013
Priority date	—
Expiry date	Jan 12, 2032

Classification

Technology area (CPC G)Physics
CPC primaryG06F7/508
WIPO fieldComputer technology
WIPO sectorElectrical engineering

Abstract

Binary code decimal (BCD) arithmetic add/subtract operations on two BCD numbers independent of which BCD number is of a greater magnitude include, responsive to the BCD arithmetic add/subtract operation being a subtract operation, performing a BCD arithmetic subtraction operation on a first BCD number and a second BCD number, the first BCD number having a first magnitude and the second BCD number having a second magnitude. The first magnitude is greater than, equal to, or less than the second magnitude. The performing includes: in parallel to a carry generation, partial sums or partial differences of the first and second BCD numbers are computer such that a final result in signed magnitude form is selectable from the partial sums or differences based on carry information without any post processing steps.

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