Title:
IC CARD AND ERASING METHOD FOR ITS DATA STORAGE MEMORY
Document Type and Number:
Japanese Patent JP2779092
Kind Code:
B2
Abstract:
PURPOSE: To disable writing, reading, and erasure in an area regarding the application program in an E2PROM.
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 E2PROM is enabled.
Inventors:
KIMURA TAKESHI
NANBA SEIICHI
KUBO TAKASHI
NANBA SEIICHI
KUBO TAKASHI
Application Number:
JP6714592A
Publication Date:
July 23, 1998
Filing Date:
March 25, 1992
Export Citation:
Assignee:
NIPPON HOSO KYOKAI
HITACHI MAKUSERU KK
HITACHI MAKUSERU KK
International Classes:
G06K17/00; G06K19/07; G06K19/073; G06K19/10; G11C16/02; G11C16/06; G11C17/00; (IPC1-7): G06K19/07; G06K17/00
Domestic Patent References:
| JP62103742A | ||||
| JP61235994A | ||||
| JP259937A | ||||
| JP2157988A |
Attorney, Agent or Firm:
Kenjiro Take (1 person outside)