| 摘要 |
<p>PROBLEM TO BE SOLVED: To eliminate erasure before writing and increasing a writing speed by rewriting the sector information of an address specified externally to information in a surplus storage region based on the address exchange information of an address exchange circuit. SOLUTION: A control circuit 20 controls the operation of an address exchange circuit 19, a low decoder 12, and a column selection circuit 14 by receiving control information from a control buffer 17. Then, an erasure operation is made to the unit sector of an address in write-disable state, when a surplus bit has been set and a writecompletion bit has been set. Then, after the erasure, the write-completion bit of a sector information region corresponding to a memory array 18 for sector information is set. In this manner, the control circuit 20 for rewriting the sector information to address information on the main memory array of the sector of the address instead of the surplus sector is provided, thus eliminating the need for erasure before writing.</p> |
