| 摘要 |
PURPOSE:To prevent a password from being exposed to a 3rd party by not displaying a password set by the user, deleting the password automatically after the end of data transfer and displaying the presence of the setting of the password. CONSTITUTION:A password entered by the user is stored in a password memory table of a RAM 3 of each data transfer device and only when the password is set, it is displayed and the password set once is not displayed externally afterward. A CPU 1 of a data transfer device at a sender side reads the password from the RAM 3 and gives a command of transmission start request to a communication control section 9 together with the password. A password in a reception I frame is fetched in the CPU 1 in the communication of a data transfer device at a receiver side, whether or not the password in the RAM 3 in its own device is coincident is discriminated, the CPU 1 gives a command of start reply transmission to the communication control section 9, which sends one frame of start reply. |
