Abstract: The method provided first partitions the memory, which has defective cells at unknown locations, into a plurality of frames. Each of the plurality of frames has a corresponding N-bit of cell, and M-bit of cell for storing an index representative of the defectiveness of the (M+N)-bit cell. Secondly, the method performs a predetermined pattern write-read access test to the corresponding (M+N)-bit cell for each frame to determine if the (M+N)-bit of cell is defective. Thirdly, the method stores a first value of the index into the corresponding M-bit of cell for each frame, if the (M+N)-bit cell is good. Fourthly, the method stores a second value of the index into the corresponding M-bit of cell, if the (M+N)-bit cell is defective.