| 摘要 |
PROBLEM TO BE SOLVED: To prevent the illicit access to data stored in a storage by a third person. SOLUTION: A firmware necessary for the read and write to a storage medium 26 is not stored in a nonvolatile memory 24 but downloaded to a volatile memory 23 from a host device. When a download command of firmware is issued from the host device, an interface control part 21 reports the receipt of the command to a processor 22. The processor 22 analyzes the command received in the interface control part 21 and, when it is the download command of firmware, successively stores the firmware transmitted from the host device in the volatile memory 23. Since the content in the volatile memory 23 is lost every cut of a power source, the access to the storage medium 26 by the third person can be prevented. |
