JPS6321197A - Ic card - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Technical Field> The present invention has a built-in microprocessor and memory, and an I/O
An IC that executes transactions for a desired application when connected to a C card reader/writer or various terminals equipped with the reader/writer.
Regarding the card, the microprocessor is used to effectively utilize the number of times the memory is repeatedly written.

<Prior art> Correction of data stored in an IC card with a built-in non-volatile memory such as EEPROM,
There are various methods for editing processing such as changing or erasing.
In all conventional methods, editing is performed after all data in the memory is moved to a storage RAM (random access memory), and when editing is completed, all data is written to the memory again. This method is adopted.

Therefore, it can be said that the conventional IC card does not effectively utilize the number of times the memory is repeatedly written.

<Object of the Invention> In view of the above circumstances, the present invention inspects the usage status of a memory area in which a transactional application is stored when a transaction is executed, and removes garbage existing in the area based on the inspection result. To provide an IC card that performs garbage collection (garbage collection) and thereby controls generation of free space, thereby effectively utilizing the number of repeated writes to the memory.

<Example> Hereinafter, the present invention will be explained with reference to the drawings.

FIG. 1 shows an IC card and its terminal to which the present invention is applied.

In the figure, 1 represents an IC card, and the IC card 1 is an I
It is inserted into the C card reader/writer 2. After inserting the IC card], the reader/writer 2
Transaction (t
transaction )), that is, conduct a transaction.

As shown in FIG. 2, the IC card 1 includes a microprocessor CPU1a, a memo IJ1b storing a control program, and a non-volatile memo 'J' consisting of an EEPROM.
lc and RAMId are built-in.

Further, in the figure, 1e is an external terminal of the IC card 1, and the external terminal 1e is the connection terminal 2 of the read/writer 2.
connected to a. The read/writer 2 internally includes a CPU 2b and a memory 2c storing a discrimination program in order to exchange data between various devices 3 and the IC card 1.
It also has an interface IF2d.

In the nonvolatile memo 'JIc' provided in the IC card 1, if the unusable data area or the erased area is left unused, the memory usage rate will decrease. It uses the built-in microprocessor to perform data sorting and create free space.

Note that the read/writer 2 may be independent or incorporated into various terminals;
A device that includes a C card card/writer is called a terminal.

To give an example of a transaction (a transaction in which information is exchanged), a card is inserted after selecting a transaction such as deposit, withdrawal, bookkeeping, or inquiry at a bank's ATM or DC equipment. , enter your 4-digit PIN to confirm your identity, enter the amount for withdrawals, display the amount for deposits, and respond to the confirmation key press to process the data on the host device.・The update is executed and the card is ejected at the end, but the processing after the transaction selection is called a transaction.

FIG. 3 is a flowchart showing the overall processing of the IC card according to this embodiment.

The following is a step-by-step explanation.

After the IC card is inserted into the terminal, the system of the IC card is set so that transactions can be made with the target application (step S1).

Setting up the IC card system means establishing a protocol between the IC card and the terminal and authenticating the validity of the IC card. Here, the protocol is to secure and set a transmission method that satisfies both parties between various types of IC cards and terminals, so that data signals can be transferred freely. To tell. Further, the validity of the IC card is verified by confirming (checking) the history of the IC card, and if the history is correct as a result of the confirmation, it means that the IC card is approved as being correct. As a result, data transfer between the IC card and the terminal (
Proceed to the next step in the protocol. Note that the history of the IC card is a record of evidence of unauthorized access to the IC card or a record of an accident, and cannot be accessed in the case of an unauthorized IC card.

Next, the user selects an application for conducting a transaction and starts accessing the selected application (step S2).

The application with which the transaction is to be made is selected by displaying the application directory on the terminal and specifying it. For example, a user enters a PIN number to verify his or her identity, and if the input PIN is verified and the PIN is correct, the application can be accessed.

Then, the transaction area for the target application (the area where the application to be transacted is stored) is grasped, and the first address to the last address of the transaction area are stored. This completes the transaction area address setting (step S3).

Next, the usage status of the transaction area specified in step S3 is checked, ie, whether it is an in-use data area, an erased data area, or a free area, and the addresses of each status are stored (step S4).

Based on the result of checking the usage status of the transaction area, the microprocessor determines whether garbage collection of the transaction area is necessary (step Ss).

Garbage refers to meaningless data in a storage device that has become meaningless due to an error or is leftover data from a previous unrelated job.

If the microprocessor determines that it is necessary to perform garbage collection of the transaction area, it moves to step S6, executes this, and refills the data field (step S6).

When the processing of step S6 is completed, the process moves to step S7, and the transaction of the target application is executed.

If the microprocessor determines in the previous 2ss step that garbage collection of the transaction area is not necessary, the process directly moves from the S5 step to the S7 step.

After executing the transaction, the result is stored in non-volatile memory (step S8).

Here, garbage collection (garbage collection)
will be explained using FIG.

FIG. 5A shows the stored contents of the memory before garbage collection is performed, in which the memory is used sequentially from the end and some unnecessary data is deleted along the way. In the figure, the part clearly marked as free indicates an empty area (area) where no data is stored.
The other data storage areas are divided into A, B, C, and D by the free areas.

If an attempt is made to store additional data E, which requires a large area as shown in FIG. 3(b), in the memory shown in FIG.

Therefore, as shown in FIG. 3(c), the free space existing between the divided data storage areas is eliminated and the data is repacked. That is, the data storage area B is moved so that the first address and subsequent addresses of the data storage area B are set after the final address of the storage area A. Subsequently, the data storage area C is moved so that the first address and subsequent addresses of the storage area C are set after the dispersion and ending address of the storage area B. Thereafter, similar operations are performed on the remaining storage areas, and finally a free area capable of storing the additional data E is generated, and the additional data E is stored in the generated free area.

Then, during the transaction, the microprocessor of the IC card searches and determines whether or not there is free space in the area for recording transaction results for the application. At this time, it is calculated how much recordable area remains from the specified address (the first address of the free area).

As a result, an algorithm is built into the ROM or the like to collect garbage when the size of the remaining free space reaches a certain condition. For example, if deposits and withdrawals of bank deposits are taken up, and as a result of the transaction, only 5 data items remain in memory, there is a possibility that the memory recording area will run out within a few days, so garbage It is necessary to collect

FIG. 5 shows a flowchart of transaction area check processing. This shows step 84 in FIG. 3 in detail.

First, the designated starting address is set to 7,7) (step S21).

Thereafter, the data is inspected one record at a time in order from the set start address (step S22).

Here, record unit means the unit of data that constitutes transaction result data. For example, in the case of financial transactions, transaction information and its results are recorded in memory, so it is used as a general data item. , date/time, summary.

Possible items include amount, balance, 9-store food, terminal code, and reserve items. These are expressed in record format as shown in Figure 6.

Inspection involves determining whether a record of data exists (
It is determined whether the data records in steps S23 and 524 are valid or unusable (step S24, knob).

As a result, two addresses, ie, the data area in use and the addresses of the other data areas, are stored (step S25).

The inspection is repeated until the entire specified transaction area is covered, and if the entire area has not been inspected (step S26), the address is updated (step S27).
22 Step G returns.

When it is determined that the inspection of the entire transaction area has been completed (step S26), the information from the step S25 is summarized (step 828).

FIG. 7 shows a flowchart of garbage collection processing. This shows step 86 in FIG. 3 in detail.

Based on the information obtained in step S28 in FIG. 3 described above, the original address and destination address at the beginning are set (S3
1 step) 0 The data is moved between the set original address and the destination address, that is, the data is repacked (step S32).

When the process of step S32 is completed, it is determined whether the original address at which the process of step S32 was performed is the last one (step S33).

If the original address is not the final address in step S33, the original address and destination address are updated (step S34), and the process returns to step S32.

In this way, when the original address becomes the final address, G (S3
3), the garbage collection process is completed. The present invention is applicable not only to existing IC cards without a display section, but also to new type IC cards with a display.

In the present invention, the microprocessor of the IC card is provided with intelligence regarding the timing and conditions for performing garbage collection processing.

In other words, by incorporating a memory management algorithm into the ROM, etc. of the IC card, garbage collection is executed at the time of executing a transaction for the target application, and moreover, it is possible to perform this all the time. Instead, only when certain conditions are met.

<Effects> As described above, according to the present invention, in an IC card that has a built-in microprocessor and memory and is connected to a terminal to execute an application transaction, an application to be transacted is stored when a transaction is executed. Since the usage status of the memory area is inspected, and based on the inspection result, the garbage existing in the area is collected and control is performed to generate a free area, the following effects are obtained.

D) The ability to effectively utilize the number of repeated writes to memory, which is a physical and electrical limiting condition.

(b) Free memory space can be quickly secured by collecting garbage and repacking the data in the transaction area.

(c) Garbage collection processing is not performed every time an IC card is inserted into a terminal, but garbage processing is performed based on the results of the microprocessor's investigation of the transaction area, thus preventing time loss. can.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an IC card and a terminal to which the present invention is applied, FIG. 2 is an internal block diagram of the IC card and terminal, and FIG. 3 is an overall diagram of an IC card according to an embodiment of the present invention. Flowchart showing the process, FIG. 4(a) to (c) are diagrams for explaining the garbage collection process, FIG. 5 is a flowchart showing the inspection process of the transaction area of the IC card, and FIG. 6 is a flowchart showing the transaction result. FIG. 7, a diagram showing the data, is a flowchart showing the garbage collection process of the IC card. 1...IC card, la...microprocessor,
1c...Memory, 2...Read/Writer. Figure 3 Figure 5 (t)
(b) (C) @Figure 4Figure 6

Claims (1)

[Claims] 1. An IC card that has a built-in microprocessor and memory and is connected to a terminal to execute application transactions.When a transaction is executed, the usage status of the memory area where the transactional application is recorded is inspected, and the inspection results are recorded. An IC card characterized in that based on the above, garbage existing in the area is collected and control is performed to generate a free area based on the collected garbage.