| 摘要 |
A system using RAM is provided to prevent intrusion to set a protection area and block access to it, so preventing intrusion to the protection area and increase the reliability of the system. In a system using RAM, a random access memory inputs and outputs data or code and a controller generates the code or data to be inputted or outputted into/from RAM and controls input and output operation. A memory control unit outputs an address of the RAM used for the controller and a write signal according to command and information supplied from the controller. An address analysis unit outputs a memory protection enable signal when the address which the memory control unit outputs is included in the protection area. A protection unit protects receives the memory protection enable signal provided from the address analysis unit and blocks the memory address when the memory address and write enable signal are provided from the memory control unit. |
