METHOD AND APPARATUS FOR DETECTING FREE PAGE AND ERROR CORRECTION CODE DECODING METHOD AND APPARATUS USING THE SAME

摘要

PURPOSE: A free page detecting method, an error correction code decoding method and a device thereof are provided to prevent the reduction of a memory size by normally using a page which has the number of errors within a tolerance range. CONSTITUTION: A conversion mode changing a free page data to an arbitrary codeword is established(S401). A data read from the memory is transformed by applying the preset conversion mode(S402). The transformed codeword and the preset codeword are compared according to a corresponding bit(S403). The number of total bits which are different each other according to a comparison result is detected(S404). The number of the total bits which are different each other is compared with a critical value(S405). A free page determining procedure is operated(S406). A ECC(Error Correction Code) decoding is suspended(S407). A normal ECC decoding is executed(S408).