Registers – Records – Conductive
Reexamination Certificate
2001-02-22
2003-02-25
Le, Thien M. (Department: 2876)
Registers
Records
Conductive
C235S487000, C235S437000
Reexamination Certificate
active
06523754
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates in general to a contact type of IC card which reads/writes data through a particular terminal, or a non-contact type of IC card which reads/writes data through a radio interface. More particularly, this invention relates to a technology for normally restoring data and a message relating to an interrupted processing if the processing is stopped due to the interruption of the supply of power or the supply of radio wave or if data which is being received is discontinued and the processing is then resumed.
BACKGROUND OF THE INVENTION
In recent years, IC cards each including a CPU and having a higher capacity than that of a magnetic card have been introduced in many places. The IC card has been studied as a successor to the magnetic card and gradually employed as, for example, a credit card or a personal card for storing welfare/health data. In the future, it is expected to spread IC cards each of which can be used as a multifunctional card system allowing a single card to fulfill the functions of various types of cards or a card system allowing a user to receive more services in cooperation with other card service businesses.
The operation of a conventional IC card will be described here. A contact IC card, for example, is supplied with power from a host apparatus through a power terminal and operates an IC chip in the IC card. A non-contact IC card, on the other hand, is supplied with radio wave from a host apparatus, converts the received wave into power in the IC card and operates an IC chip.
The data write processing flow of the conventional IC card will be described.
FIG. 11
is a flow chart showing a data write processing flow. First, a host apparatus transmits an update command (including update data) to the IC card (in a step S
101
). The host apparatus then turns into a state of waiting for a response from the IC card.
The IC card receives the update command from the host apparatus (in a step S
102
), and searches for a place where data is to be updated based on control information (which is pointer information indicating up to which region data was written in a previous processing) stored within the IC card (in a step S
103
). At this moment, the IC card writes update data to the next region (or address) to that of the previous data stores in a memory region (in a step S
104
). After completing writing data, the IC card updates the control information (in a step S
105
) and further transmits a response indicating that a write processing was normally ended, to the host apparatus (in a step S
106
).
Finally, the host apparatus receives the response from the IC card with which the host apparatus communicates and previously transmitted the update command, and ends a series of data write processings (in a step S
107
).
In this way, the conventional IC card rewrites data under the control of the host apparatus, whereby the data stored in the memory such as credit card information, personal information for storing welfare/health data and charge information, can be always held in an update state.
In IC cards in general, however, power may possibly be stopped during a write processing for some reason. If so, the operation of the IC card is stopped. In case of the contact IC card, for example, this may be because the supply of power from the host apparatus is interrupted due to some trouble, a contact failure occurs to a power supply terminal, the IC card is released (including a case where the IC card is purposely released) or the like. In case of the non-contact IC, by contrast, this may be because the supply of radio wave from the host apparatus is interrupted due to some trouble, an IC card user is away from areas radio waves can reach or the like.
In the above case, the supply of power to the conventional IC card is interrupted and the processing is stopped halfway. The host apparatus cannot grasp up to which processing the IC card has carried out and from which processing the host apparatus allows the IC card to carry out when the IC card is restarted. As a result, the conventional IC card is confronted with a disadvantage in that the data written in the IC card which data the host apparatus recognizes and the data actually written to the IC card contradicts.
FIG. 12
illustrates a problem in a case where old data of five bytes already stored in the IC card is updated to new data of five bytes. In
FIG. 12
, it is particularly assumed that the supply of power to the IC card is stopped while data is being written to the IC card or the IC card cannot receive data from the host apparatus. For example, if the supply of power is stopped when data of the third byte has been written to the IC card, a data write processing is ended at that point. As a result, the data which has been written the moment the data write processing is stopped differs from what should be originally written to the IC card.
FIG. 13
shows a concrete example of the above-stated problem. Time zones in which the supply of power is stopped may be the following three zones. The first time zone is one, as shown in {circle around (
1
)} in
FIG. 13
, before the IC card recognizes an update command, i.e., the supply of power is stopped before a write operation is started. In the first case, if power supply is recovered and restarted, the IC card can read the state of control information before the supply of power is stopped. However, since the write processing is not completed when the supply of power is stopped, the IC card cannot transmit a response signal for notifying the host apparatus of this state. The second time zone is one, as shown in {circle around (
2
)}, in which the supply of power is stopped while data is being written to the IC card. In this case as in the case of (
1
), the IC card can read the previous state of control information when the IC card is restarted but cannot transmit a response signal to the host card. The third time zone is one, as shown in {circle around (
3
)}, in which the supply of power is stopped after a data update processing is finished and new control information is written. In the third case as in the case of (
1
) and (
2
), the IC card can read the new state of control information when the IC card is restarted but cannot transmit a response signal to the host apparatus.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an IC card, a data update control method, a data/message restoration control method and a recording medium storing a control program capable of normally restoring a processing which was executed until the operation of the IC card is stopped when the IC card is restarted even if the supply of power (to the contact IC card) or the supply of radio wave (to the non-contact IC card) is stopped for some reason.
The IC card according to one aspect of this invention comprises a first storage region in which written data is not guaranteed; a second storage region in which the written data is guaranteed; a third storage region in which a status bit indicating a processing state is stored; and a processing section. When the processing section receives a first command to write the data without guarantee from a host apparatus, it sets the status bit corresponding to a write processing at a state indicating a non-guarantee write processing and writes the received data to the first storage region. On the other hand, when processing section receives a second command to write data with guarantee from the host apparatus, it sets the status bit corresponding to the write processing at a state indicating a guarantee write processing and writes the received data to the second storage region.
According to the above-mentioned aspect, one of “the data guarantee region” and “the data non-guarantee region” is designated using a predetermined command, thereby guaranteeing important data relating to operations between the host apparatus and the IC card. Thus, even if the supply of power (to the contact IC card) or the supply of radio wave (to the non-contact IC card) is stopped for some reason, for exam
Hoshino Masao
Seki Yuji
Shiobara Tomomi
Armstrong Westerman & Hattori
Cyr Daniel St.
Fujitsu Limited
Le Thien M.
LandOfFree
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