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:
Nov. 18, 1997
Filed:
Apr. 02, 1996
Robert D Maher, III, Carrollton, TX (US);
Cyrix Corporation, Richardson, TX (US);
Abstract
A method of detecting anomalous overflow conditions is used, in an exemplary embodiment, in implementing in a 486-type microprocessor, nonrestoring two's complement division for negative quotients using 2n bit dividends and n bit divisors. Each interative division step, an adder/subtractor is used to add/subtract the properly aligned divisor to/from the left shifted dividend, to produce a partial remainder and a carry out bit Cout. Complement Cout is assumed to be the same as the most significant bit of the partial remainder PR(MSB), such that PR(MSB) is used as the sign bit in further computations, with complement Cout being used to control quotient generation according to DVRS XOR Cout. The anomalous overflow test signals overflow when complement Cout is the different than the most significant bit of the first partial remainder PR1(MSB), such that the anomalous overflow test is implemented according to the logic equation: Cout XNOR PR1(MSB).