JPH06309527A - IC card - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an IC card capable of recovering erased data. [Structure] The IC card 1 transmits / receives data to / from an external device through an input / output unit 2. The memory management means 4 includes at least a writing means 7, an initialization means 8 and a recovery means 9.
The non-volatile memory 3 for storing the data written by the writing means 7 can be initialized by the initialization means 8, and the initialized data can be recovered by the recovery means 9. It is possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card capable of erasing information in a memory.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram of a conventional IC card. In FIG. 5, 10 is an IC card, 11 is a volatile memory, 12 is an input / output means, 13 is a non-volatile memory, 14
Is a memory management means. A method of initializing all information other than system information in the memory of the conventional IC card will be described.

The conventional IC card 10 has an input / output means 12
Send and receive data with external devices through. The memory management unit 14 is composed of at least a writing unit 17 and an initialization unit 18, and the nonvolatile memory 13 for storing the data written by the writing unit 17 has a system area 15 for storing information of the memory management and a business use area. It comprises a user area 16 for storing information.

Since the system area 15 and the user area 16 are physically one medium (here, the nonvolatile memory 13), the initialization means 18 first saves the information in the system area 15 to the volatile memory 11 first. , 1 is written in all the bit units of the non-volatile memory 13 to initialize it. There is a method in which power is supplied to set all bit units to 1 or 0. Since this is a physical method, high-speed processing is possible.

Next, the initialization means 18 uses the volatile memory 11
The information saved in the system area 15 is returned to the system area 15, the information for managing the user area 16 is rewritten to the initial information, and the IC card 1 is initialized.

[0006]

In the conventional IC card, since 1 or 0 is written in all the bit units of the non-volatile memory, the initialization process takes time and the initialized user area of the IC card is initialized. It was not possible to return to the state before conversion.

In view of the above point, the present invention has an object to provide an IC card capable of recovering erased data.

[0008]

In order to achieve the above object, the IC card of the present invention has an input / output means for transmitting / receiving information to / from the outside, a system area for storing management information, and a user for storing information. A memory consisting of a user area to store,
The system area includes at least a user management area for storing user management information of the user area and a save area for temporarily saving the user management information. The memory management unit has an initialization unit that stores the user management information in the save area and restores the user management area to an initial state according to an instruction from the outside, and the save area according to an instruction from the outside. And a recovery means for restoring the user management information stored in the user management area to the user management area.

[0009]

According to the IC card of the present invention, the data writing process at the time of initialization is simplified and speeded up, and the state before initialization is retained without being erased, so that the initialized user area is obtained. Can be recovered.

[0010]

EXAMPLES Example 1 Hereinafter, a first example of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of an IC card according to a first embodiment of the present invention. In FIG. 1, 1 is an IC
Card, 2 is input / output means, 3 is non-volatile memory and 4
Is a memory management means. A method of initializing all information other than system information in the memory in the IC card of this embodiment will be described.

The IC card 1 of this embodiment is composed of input / output means 2
Send and receive data with external devices through. The memory management unit 4 includes a writing unit 7, an initialization unit 8, and a recovery unit 9. The non-volatile memory 3 comprises a system area 5 for storing memory management information and a user area 6 for storing business information, and data is written by the writing means 7.

FIG. 2 shows the details of the block diagram of the nonvolatile memory of the IC card in this embodiment. It is assumed that the user area 6 has a plurality of information already written by the writing means 7 and has an empty area. The system area 5 includes a plurality of pointers for managing the user area 6, an area for saving the pointers, an initialization flag, and other system information. The pointer 1 of the system area 5 is the user area 6
The beginning address of the empty area of is stored. There are as many save areas as there are pointers. The initialization flag of the system area 5 stores the state (for example, 0) before the initialization unit 8 is executed.

When the initialization means 8 is executed to initialize the user area 6, all pointers for managing the user area 6 including the pointer 1 for storing the start address of the free area of the user area 6 are saved. Save to area. Here, the pointer 1 is saved in the save area 1, and the pointer 2 is saved in the save area 2. After this, the initialization means 8 sets the user area 6
The initialization flag is set to 1 without any change, and the initial address of the information 1 of the user area is stored in the pointer 1 of the system area 5 to complete the initialization processing.

When it is desired to restore the original user area after the initialization by the initialization means 8, the recovery means 9 is executed. First, the recovery means 9 confirms the initialization flag of the system area 5, and when the initialization flag is 1, determines that the recovery is possible, and the pointer 1 stores the information stored in the save area 1 of the system area 5, The information stored in the save area 2 is returned to the pointer 2 and the initialization flag is set to 0. If the initialization flag is 0 at the confirmation stage, it is determined that the recovery is impossible and the processing is interrupted.

The initialization flag of the system area 5 is set to 0 when the writing means 7 is executed. That is, the recovery unit 9 can be executed after the initialization unit 8 is executed and before the writing unit 7 is normally executed.

As described above, in the IC card of this embodiment, since it is not necessary to write 1 or 0 in all the bit units of the non-volatile memory, the initialization processing time is shortened. Further, since the data itself in the user area is not lost even after the initialization, the user area can be recovered.

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a block diagram of an IC card according to the second embodiment of the present invention. 21 is an IC
A card, 22 is an input / output unit, 23 is a non-volatile memory, and 24 is a memory management unit. A method of invalidating the information stored in the memory of the IC card of this embodiment will be described.

The IC card 21 of this embodiment transmits / receives data to / from an external device through the input / output means 22. The memory management means 24 comprises at least a writing means 27, a deleting means 28 and a recovering means 29, and the writing means 27.
Non-volatile memory 2 for storing the data written by
3 is a user area 2 for storing business information in a record
It consists of six.

FIG. 4 shows a block diagram of a record of the IC card in this embodiment. The writing unit 27 writes the data received through the input / output unit 22 in the record 30 by adding the valid / invalid flag and the record number. Here, the valid / invalid flag is set to 1, which means valid, and the record numbers are added with uniform and consecutive numbers.

When the written record becomes unnecessary, the deletion means 28 is executed to set the valid / invalid flag of the record to be erased to 0, thereby making the record invalid. Here, the deletion means 2 is erroneously
If step 8 is executed, the recovery means 29 is executed to set the valid / invalid flag of the erased record to 1, so that this record can be validated. However, the recovery means 29 suspends the execution when the designated record is already valid. Note that the recovery unit 29 can be executed after the deletion unit 28 is executed and before the writing unit 27 is normally executed.

As described above, according to the IC card of the present embodiment, even if the record is invalidated, the information of the record is retained, so that the information stored in the invalidated record can be recovered.

In the above embodiment, an IC card having a rewritable non-volatile memory was used, but it goes without saying that an IC card having a power source and a volatile memory that holds data by this power source may be used. Yes.

[0023]

As described above, according to the present invention, when the initialization flag is 1, the pointer for managing the user area can be recovered from the save area, and the user area of the IC card before the initialization is restored. It became possible to return to. Furthermore, it is possible to recover even if the information stored in the record in the user area is deleted.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an IC card according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a nonvolatile memory of the IC card according to the first embodiment of the present invention.

FIG. 3 is a configuration diagram of an IC card according to a second embodiment of the present invention.

FIG. 4 is a block diagram of a record of an IC card according to a second embodiment of the present invention.

FIG. 5 is a block diagram of a conventional IC card

[Explanation of symbols]

 1 IC card 2 I / O means 3 Non-volatile memory 4 Memory management means 5 System area 6 User area

Claims (4)

[Claims] 1. A memory comprising input / output means for transmitting / receiving information to / from the outside, a system area for storing management information, and a user area for storing information by a user, and writing / reading control to / from the memory. The system area includes at least a user management area for storing user management information of the user area, and a save area for temporarily saving the user management information. , An initialization unit that stores the user management information in the save area according to an instruction from the outside and returns the user management area to the initial state, and stores the user management information stored in the save area according to an instruction from the outside. An IC card, comprising: a recovery unit for returning to the user management area. 2. The IC card according to claim 1, wherein the recovery means can be executed only when the initialization means is executed and the user area is not written. 3. A memory comprising input / output means for transmitting / receiving information to / from the outside, a system area for storing management information, and a user area for storing information by a user, and writing / reading control to / from the memory. Memory management means for performing the user area, the user area comprises at least one storage partition, the system area has a flag indicating whether the information of the storage partition is valid or invalid for each of the storage partition, The memory management unit invalidates the information in the storage partition by setting the flag invalid according to an external instruction, and enables the flag invalidated by the deletion unit according to an external instruction. An IC card, comprising: a recovery unit that validates information in the invalidated storage section. 4. The IC card according to claim 3, wherein the recovery means can be executed in the storage section in which the information is not written only when the deletion means is executed.