| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor memory device in which even if the inexpensive semiconductor memory of a block access type is used for a storage medium, this can be treated as a normal system memory which can be accessed at random, and its access method and a memory control system. <P>SOLUTION: This semiconductor memory device 19a is provided with a NAND type flash memory 17a as a first semiconductor memory and an SRAM 18a as a second semiconductor memory, wherein the SRAM 18a is the cache of the flash memory 17a, and the flash memory 17a is accessed through the SRAM 18a. A first address region and a second address region are arranged in a logical memory address to be accessed from the outside, and a portion of the SRAM 18a is mapped in the first address region. Also, a control circuit 16a controls data transfer between the flash memory 17a and the SRAM 18a by carrying out memory-accessing of the second address region. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
