MEMORY CONTROLLER, AND METHOD OF CONTROLLING SEMICONDUCTOR MEMORY

PROBLEM TO BE SOLVED: To decrease the access frequency of a semiconductor memory without impairing the reliability of a system and improve the performance of the system. SOLUTION: A data search part, when writing in the semiconductor memory the write data of a smaller size than the data held in the storage area of the semiconductor memory, searches for a free storage area where no data is written. A rewriting register has a plurality of storage parts for holding the data corresponding to the free storage area. A write control part sequentially writes the write data in the storage parts, and writes the data held in the rewriting register in the corresponding storage area in response to writing of the write data to the last storage part of the rewriting register. A state flag is set when the write data is written in the rewriting register. Thereby, the access frequency of the semiconductor memory is reduced while preventing access of incorrect data. COPYRIGHT: (C)2011,JPO&INPIT