MEMORY CONTROLLER AND FLASH MEMORY SYSTEM

PROBLEM TO BE SOLVED: To provide a memory controller and a flash memory system that can reduce search time for an empty block. SOLUTION: An empty block search table 100 indicating a use state of physical blocks of a flash memory is provided in the work area of a memory controller. The use state of each physical block is represented by 1 bit data in the empty block search table 100. The data indicating the use state is read per predetermined bit string unit, and an empty block is detected based on the bit string data. A group is configured by collecting two or more pedetermined bit strings. Data indicating the number of empty blocks included in each group is stored. Reading the bit string belonging to a group whose number of empty blocks is zero is skipped based on the data indicating the number of empty blocks. COPYRIGHT: (C)2007,JPO&INPIT