| 摘要 |
PURPOSE:To secure confidentiality of data stored in recording media by converting or not-converting write/read data in accordance with selection. CONSTITUTION:When a low-level selecting signal is impressed to a terminal 12 from a CPU, buffers 19 and 21 becomes the dead state, conversion and inverse conversion will not be carried out by exclusive OR circuits 17 and 18, which are connected through invertors 15 and 16 becoming the operational state for a terminal 10 at the CPU side, and terminals at recording media side such as a disk. Information from the CPU side is written in recording media without conversion, and that from recording media is read out to the CPU side without inverse conversion. On the other hand, circuits for conversion and inverse convertion become unable through invertors 19 and 21 which are brought into the operational state when a selecting signal becomes a high level, writing and reading by converting information are executed; therefore confidentiality of data stored in recording media can be secured. |
