Patent ID: 7530009
Filing Date: 2009-05-05
Classification: G11B

Abstract:
1. A data storage device comprising: a disk storage medium having a plurality of sectors containing the user data wherein each of the plurality of sectors comprises a subdivision of a track; a head for performing a writing process or a reading process into or from said disk storage medium upon a write command or a read command transferred from a host; and error correcting means for correcting an error that occurs in said data during said reading process; wherein said error correcting means makes the error correction, using a first error correcting code appended to each of a plurality of sectors and a second error correcting code appended to said sector for every block composed of a predetermined number of sectors; and comprises: a syndrome generator for generating a syndrome on the basis of said user data; a Euclid circuit for constructing an error locator polynomial and an error evaluator polynomial on the basis of the syndrome generated by said syndrome generator; a chien search circuit for solving said error locator polynomial and said error evaluator polynomial; and a verification circuit for verifying the validity of the solutions of said error locator polynomial and said error evaluator polynomial in said chien search circuit; wherein an operation process for updating said syndrome after the end of making an error correcting process with said first error correcting code is performed using said Euclid circuit and said chien search circuit, wherein said Euclid circuit comprises a general-purpose multiplier, said chien search circuit comprises a first register and said operation process is performed by said general-purpose multiplier to acquire a first operation result, which is saved temporarily in said first register.