Iterative decoding of multiply-added error-correcting codes in a data processing error correction device

A data error correction method of correcting errors in data by subjecting error-correcting codes which are multiply added to the data, to iterative decoding up to a predetermined number of times, wherein

• even when the number of times of the decoding is less than the predetermined number of times, the error correction processing is terminated when it is judged that the data have no error, and a clock signal which is necessary for the error correction processing is stopped during a period until the iterative decoding for next data is started, said method including the steps of:
• an uncorrectability detection step of detecting presence or absence of uncorrectable codewords in a present decoding;
• a detection result holding step of containing a result of the detection in the uncorrectability detection step, corresponding to decoding immediately precedent to the present decoding;
• a syndrome zero detection step of detecting that syndromes of all codewords in the present decoding are zero;
• a correction termination judgement step of judging termination of the correction processing when no uncorrectable codeword is detected in the decoding immediately precedent to the present decoding and the syndromes of all the codewords in the present decoding are zero;
• and
• a control step of stopping a clock signal which is necessary for the error correction processing during a period after the error correction processing during a period after the error correction processing is terminated in accordance with the correction processing judgement step when the number of times of the decoding is less than the predetermined number of times, till the iterative decoding for the next data is started.