| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To protect the security of data written in a semiconductor memory by improving the performance of a system. <P>SOLUTION: In a conversion control part, a conversion function of a write-in data converting part or a read-out data converting part is set validly or invalidly for each controller. External data is thereby input/output for a controller requiring the original external data, and internal data is input/output for a controller requiring converted internal data. Since the data conversion function possessed by a conventional controller is realized in the semiconductor memory, burden of the controller is lightened. Performance of the system is thus improved. An invalid controller having no access-right cannot read out correct data (original data before conversion). Security of data written in the semiconductor memory is protected thereby. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
