Claims
- 1. A method of writing and erasing data in a memory device with a memory area having a plurality of blocks each with a plurality of sectors, the memory device erasing data by the unit of one block, the method comprising:selecting a first predetermined number of blocks from a top of a first list in which the blocks are ranked in a descending order of a number of necessary sectors in each of the blocks; selecting a second predetermined number of blocks from a top of a second list in which the blocks are ranked in an ascending order of a number of necessary sectors in each of the blocks; and evacuating the necessary sectors from the first predetermined number of blocks and a second predetermined number of blocks to other blocks which have free sectors.
- 2. The method as claimed in claim 1, wherein said evacuating the necessary sectors distributes the necessary sectors to the other blocks by mixing the necessary sectors from the first predetermined number of blocks and the necessary sectors from the second predetermined number of blocks.
- 3. The method as claimed in claim 1, wherein said evacuating the necessary sectors distributes the necessary sectors to the other blocks evenly.
- 4. The method as claimed in claim 2, wherein said evacuating the necessary sectors distributes the necessary sectors to the other blocks evenly.
Priority Claims (1)
Number |
Date |
Country |
Kind |
5-246547 |
Oct 1993 |
JP |
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional of application Ser. No. 09/688,858 filed Oct. 17, 2000, now U.S. Pat. No. 6,584,579B1, which is a divisional of application Ser. No. 09/385,998 filed Aug. 30, 1999, now issued as U.S. Pat. No. 6,161,163, which is a divisional of application Ser. No. 08/912,692 filed Aug. 18, 1997, now issued as U.S. Pat. No. 5,983,312, which is a divisional of application Ser. No. 08/292,213 filed Aug. 19, 1994, now issued as U.S. Pat. No. 5,802,551.
This application is related to application Ser. No. 09/010,795 filed Jan. 22, 1998, now issued as U.S. Pat. No. 6,125,424.
US Referenced Citations (14)
Foreign Referenced Citations (2)
Number |
Date |
Country |
62-283496 |
Dec 1987 |
JP |
62-283497 |
Dec 1987 |
JP |