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:
Sep. 15, 2009
Filed:
Jun. 09, 2006
Toshihiro Katashita, Tsukuba-shi, Ibaraki, JP;
Kenji Toda, Tsukuba-shi, Ibaraki, JP;
Kazumi Sakamaki, Kita-ku, Tokyo, JP;
Takeshi Inui, Higashi-murayama-shi, Tokyo, JP;
Tadamasa Takayama, Shinjuku-ku, Tokyo, JP;
Mitsugu Nagoya, Chiyoda-ku, Tokyo, JP;
Yasunori Terashima, Shinagawa-ku, Tokyo, JP;
Toshihiro Katashita, Tsukuba-shi, Ibaraki, JP;
Kenji Toda, Tsukuba-shi, Ibaraki, JP;
Kazumi Sakamaki, Kita-ku, Tokyo, JP;
Takeshi Inui, Higashi-murayama-shi, Tokyo, JP;
Tadamasa Takayama, Shinjuku-ku, Tokyo, JP;
Mitsugu Nagoya, Chiyoda-ku, Tokyo, JP;
Yasunori Terashima, Shinagawa-ku, Tokyo, JP;
Other;
Abstract
A CRC value calculator enables throughput to be improved while keeping down the increase in the size of the circuitry. This is achieved by using (n+1) basic CRC circuits to configure a CRC value calculator in which the width of the data processed during one clock cycle is m2bits. For example, when m2bits is the data width processed per calculator cycle, the CRC value calculator of this invention is configured by using selectors to serially connect a CRC circuit that processes every m2bits, a CRC circuit that processes every m2bits, . . . , and a CRC circuit that processes every m2bits. This configuration makes it possible to calculate a correct CRC value even when the remainder of an input network frame is not a multiple of m2bits. Selectors are used to select CRC circuit output according to process data width. Reduction of the operating frequency is avoided by using registers to form a pipeline between CRC circuits.