| 摘要 |
<p>PURPOSE:To perform rewriting operation at high speed by providing a table which converts a logic block address to a physical block address at the time of reading and writing operation of a block. CONSTITUTION:A table 31 stored at a position indicated with a logical block address LBi of an address conversion table 31 is read out, and a physical block address PBi corresponding to the LBi is obtained. Next, an erasing flag in the PBi is written and set to zero requiring for erasing. Next, a erasing flag and a valid flag of the physical block in a nonvolatile semiconductor memory are successively read out, and a physical block PBk in which the both are '1' is obtained. Next, new data of the LBi is written in a data section in the PBk, a valid flag is set to zero indicating validity, and the LBi is written in a logical block address section 32. Further, the content PBi stored at a position indicated with the LBi of the table 31 is rewritten to the PBk. Thereby, when the LBi is accessed thereafter, the PBk is read out from the table 31.</p> |
