| 摘要 |
PROBLEM TO BE SOLVED: To surely protect a secret code stored in a memory. SOLUTION: This memory system comprises a first memory storing secret codes; a processor having an address conversion buffer for converting a virtual address to a physical address, the processor executing a program using the virtual address; and an access propriety determination circuit for determining the propriety of access to the first memory by the processor. The access propriety determination circuit stores an access propriety determination code which is the criterion for the determination of access propriety in a second memory and, on receipt of the physical address converted from the virtual address of the access propriety determination code from the processor, determines the access propriety based on the access propriety determination code stored in this physical address in the second memory and an access code outputted from the processor that is a determination object in the determination of access propriety. COPYRIGHT: (C)2005,JPO&NCIPI
|
