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:
Feb. 23, 1999
Filed:
Nov. 21, 1997
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ; G06F / ;
U.S. Cl.
CPC ...
711114 ; 39518204 ; 371 511 ;
Abstract
A disk drive has two channels of upper interfaces, and one channel is connected to a disk array controller, and the other channel is connected between a plurality of disk drives. A data disk drive reads the old data on the recording medium, calculates the exclusive OR of the old data and the corresponding data from the disk array controller, and transfers it to a parity disk as pseudo-parity data from the other channel. The parity disk drive reads the old parity data on the recording medium, calculates the exclusive OR of the old parity data and the pseudo-parity data, and writes it as new parity data.