| 摘要 |
PROBLEM TO BE SOLVED: To provide a memory controller which has simple and inexpensive constitution and can be flexibly adaptive to a difference in capacity of a mounted memory, securely performs limit writing even for access from a shadow area, and securely detects a fault such as a runaway of a program. SOLUTION: A memory controller is provided with: an address comparison part 5 which stores only one threshold address for identifying a writing limited section from magnitude relation of an address signal ADDR into a threshold register 2 and detects magnitude relation between a portion of the address signal and the value held in the threshold register; and a mask control part 6 which masks a write control signal to a memory device on the basis of the comparison result of the address comparison part 5. When the address comparison part 5 detects the value of the address signal ADDR and the threshold address being in specified magnitude relation where writing should be limited, writing access to the memory device is invalidated. COPYRIGHT: (C)2005,JPO&NCIPI
|
