The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 05, 1986
Filed:
Sep. 30, 1983
Theodore R Staplin, Jr, Chelmsford, MA (US);
John J Bradley, Framingham, MA (US);
Brian L Stoffers, No. Billerica, MA (US);
Honeywell Information Systems Inc., Waltham, MA (US);
Abstract
A data processing system having a central processing unit (CPU) capable of performing binary and decimal arithmetic software instructions is described. The CPU includes a microprocessor which executes the binary arithmetic software instructions under firmware control. Also disclosed is an arithmetic logic unit (ALU) that functions with the CPU. The ALU has operand inputs to which are connected switched steering circuits that permit particular operands and zero operands to be selectively applied to any or all of the ALU operand inputs. This allows easy performance of special arithmetic functions such as adding a decimal operand to itself when converting the decimal operand to a binary operand, and to subtract a decimal operand from zero when complementing decimal operands.