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:
Mar. 19, 1996
Filed:
Jun. 13, 1994
Mana Saishi, Fukuoka, JP;
Takayuki Minemaru, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A product P is calculated by multiplying a multiplicand X and a multiplier factor Y which are 16-bit fixed-point numbers and binary numbers in two's complement notation. Thus obtained product P is 31-bit length and the most significant bit thereof is a sign bit. Further, the product P is rounded down or rounded off to obtain a 16-bit rounded result PR. At this time, the 15-bit rounding data R to be added to the product P is changed according to the sign of the product P which is predicted so as to obtain respective rounded results which have the same absolute value from the two products which have different signs from each other and the same absolute value. In detail, in a case of rounding-down, '0000' and 'TFFF' (both in hexadecimal numeral) are respectively generated as the rounding data when the product P is positive and when the product P is negative. In a case of rounding-off, '4000' and '3FFF' (both in hexadecimal numeral) are respectively generated as the rounding data R when the product P is positive and when the product P is negative. The rounding data is added to the less significant 15 bits of the thus calculated product P and the less significant 15 bits of the thus added result are deleted to make the remaining 16 bits the rounded product PR.