TECHNOLOGY FOR SHARING PARITY OVER PLURAL SINGLE ERROR CORRECTION CODE WORDS

摘要

PROBLEM TO BE SOLVED: To provide a technology for sharing parity over plural single error correction code words. SOLUTION: All bits of a data block are allocated to plural logical groups so that a bit corresponding to a component is allocated to a logical group (302). The allocation guarantees that only an one-bit error at most is entered into a logical group due to a component fault. Each logical group detects and corrects a bit error by using a single error correction code. A parity bit is added to a data block including plural logical groups. The parity bit can be used together with a single error correction code in order to judge whether a detected error is a single-bit error or a plural-bit error.