| 摘要 |
PROBLEM TO BE SOLVED: To provide a protection device for registers, which prevents occurrence of an error at an early stage by prevention of an unauthorized writing on the registers and detection of the unauthorized writing. SOLUTION: The protection device for the registers comprises: a protection register 126a for storing data; a master key code storing unit 106a for storing the master key code to write the data on a protected register; a comparison circuit 107a for comparing an input key code with the master key code in order to compare whether they match or not; a permission flag setting circuit 109a for setting a writing permission flag on the protected registers if results generated by the comparison circuit is matched, and for not setting a writing permission flag on the protected registers if results generated by the comparison circuit 107a is unmatched to each other; and a first signal output circuit 113 for outputting a reset signal or an interrupt signal if compared results generated by the comparison circuit 107a are unmatched to each other. COPYRIGHT: (C)2008,JPO&INPIT
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