Patent ID: 7555702

Claim:
An error correction device for correcting errors of a code word according to the code word and erasure information it acquires, the device comprising: an erasure judging circuit for judging if the code word involves erasure or not according to the erasure information; a syndrome generating circuit for generating a syndrome for the code word; a processing unit that executes software for correcting the code word for erasure according to the syndrome generated by the syndrome generating section and the erasure information when the erasure judging section judges that the code word involves erasure and causes the syndrome generating section to generate a syndrome for the code word that is corrected for erasure; and an erasure-free error-correcting section that is a hardware for correcting errors that do not involve erasure according to the syndrome generated by the syndrome generating section, wherein when the erasure judging circuit judges that the code word involves erasure, the syndrome generating circuit first generates a syndrome for the acquired code word and delivers the outcome to the processing unit, and further generates a post-erasure-correction syndrome for the code word corrected by the processing unit and delivers the outcome to the erasure-free error-correcting section, and the erasure-free error-correcting section performs post-erasure-correction error correcting according to the post-erasure-correction syndrome.