OPTICAL DISK DEVICE, METHOD FOR REWRITING ITS FIRMWARE AND ITS PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide an optical disk device in which a firmware reconstructed by a user is never rewritten. SOLUTION: This optical disk device receives an encrypted main firmware 21 for a rewriting and an encrypted key code 24 which are transmitted from a personal computer 2 and restores the encrypted main firmware 21 for the rewriting and the encrypted key code 24 by a firmware restoring means 27 to store them in a buffer memory 16 and the disk device prohibits a firmware which is different from the firmware supplied from a manufacturer from being written in the device by comparing the key code 24 stored in a nonvolatile memory 17 with the key code 24 stored in the buffer memory 16.