| 摘要 |
<p>PURPOSE:To reduce a cost at the time of constructing a file storage by using a semiconductor memory. CONSTITUTION:The external storage is provided with a file data storage area 1, a flash memory 2 being one kind of a nonvolatile semiconductor memory, a mask ROM 3 being one kind of the nonvolatile semiconductor memory similarly, a data controller 4, a bus interface controller 5 and a system bus 6. The file data storage area 1 is provided with the flash memory 2 and the inexpensive mask ROM 3. Data which are not rewritten among the data are stored in the mask ROM, and the data which is probable to be rewritten are stored in the flash memory. By realizing the different use of the memory according to the data, the cost of a storage medium usually storing the data by using only the expensive flash memory is reduced.</p> |
