| 摘要 |
<p>PURPOSE:To disable writing, reading, and erasure in an area regarding the application program in an E<2>PROM. CONSTITUTION:With a change mode key, the mode is changed from 'normal AP execution mode' to 'ROM command execution mode' and after writing, reading or erasure is carried out, an 'only-erase flag' is set to '1' when the mode is returned to 'normal AP execution mode' by change mode key resetting. When an IC card is issued to a user in this state, 'erase-only flag' is set to '1', so even when the user tries to change the mode to 'ROM command execution mode' with the change mode key after the issue, the mode is changed to 'only-erase executable mode' and only the erasure of the E<2>PROM is enabled.</p> |
