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:
Oct. 22, 2002
Filed:
Feb. 21, 2000
Daming Jin, Fort Collins, CO (US);
Dean A. Mulla, Saratoga, CA (US);
Tom Grutkowski, Fort Collins, CO (US);
Other;
Abstract
The inventive adder can perform carry look-ahead calculations for a bi-endian adder in a cache memory system. The adder can add one of +/−1, 4, 8, or 16 to a loaded value from memory, and the operation can be a 4 or 8 byte add. The inventive adder comprises a plurality of byte adder cells and carry look-ahead (CLA) logic. The adder cells determine which of themselves is the least significant bit (LSB) byte adder cell. The LSB cell then adds one of the increment values to its loaded value. The other cells add 0x00 or 0xFF, depending upon the sign of the increment value, to a loaded value from memory. Each adder performs two adds, one for a carry-in of 0, and the other for a carry in of 1. Both results are sent to a MUX. The CLA logic determines each of the carries, and provides a selection control signal to each MUX. of the different cells.