| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To protect important data, and to easily detect the occurrence of abnormality in a doubling memory device for doubling a memory accessible from a processor. <P>SOLUTION: This doubling memory device has doubled memories 3 and 4 accessible by the processor 1, and a memory switching device 2. This memory switching device 2 has the constitution connected in a switching system to write the same data in the same address of the memories 3 and 4 of doubled one and the other at data writing time when imparting a memory protective condition, connected in a switching system to transfer the data read out of one memory 3 to the processor 1 at data reading-out time, connected in a switching system to write the data only to the doubled other memory 4 at data writing time when imparting no memory protective condition, and connected in a switching system to transfer the data read out of the other memory 4 to the processor 1 at data reading-out time. <P>COPYRIGHT: (C)2003,JPO</p> |
