MEMORY CONTROL UNIT, MEMORY DEVICE, INFORMATION PROCESSING SYSTEM AND MEMORY CONTROL METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a memory control unit capable of correcting a data uncorrectable with a first ECC by using a second ECC at any timing.SOLUTION: A memory stores a first error detection-correction code corresponding to a first data unit and a second error detection-correction code corresponding to a second data unit in which plural first data units are set. An uncorrectable error occurrence flag represents whether an error which is uncorrectable with a first error detection correction code has occurred. When an access instruction accompanying data change is generated to a second data unit representing a generation of the error which is uncorrectable with a first error detection correction code has occurred, the access is prohibited. When recovering the second data unit which represents a generation of the error uncorrectable with the first error detection correction code has occurred, the second data unit is corrected by using the second error detection correction code.