JPH03276383A - Communication system for ic card - Google Patents

Abstract

PURPOSE:To improve communication efficiency with an IC card of the communication control means of a reader/writer by receiving data from the IC card in block size, storing and multiple-coupling them and transmitting them to a host computer. CONSTITUTION:When the power source of the reader/writer 23 is turned on, a hard reset instruction is transmitted from a host computer 21 and the writer 23 hard-resets a communication control means 24 and waits the inserting of an IC card 22. When the card 22 is inserted, the writer 23 gives a reset signal and initializes the card 22. The card 22 transmits ATR information to possess the information of block size, etc., to the writer 23. The means 24 receiving the ATR information executes the setting of the block size for data communication and moreover, transmits the ATR information to the computer 21. Then, the computer 21 judges which processing to make the means 24 execute, the writing processing or the reading processing and transmits a command signal to the writer 23. The means 24 judges the command signal and executes a writing or reading subroutine.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an IC card communication system that performs data communication between a host computer and an IC card via a reader/writer, and more specifically, a communication system for an IC card that performs data communication between a host computer and an IC card via a reader/writer. The present invention relates to an IC card communication system that stores read data of a predetermined block size in its memory, then combines a plurality of pieces of data and transmits the combined data to a host computer.

<Prior Art> Conventionally, in IC card communication systems, data is exchanged between a host computer and an IC card via a reader/writer. In that case, the data is generally sent in units of messages of arbitrary size.

However, when this message is long, for transmission reasons, this data is stored in units of a certain block size (e.g., I
The data is divided into 256 bytes (defined by the human output buffer of the C card) and transmitted or received.

Therefore, data exceeding this block size (256 bytes) (for example, 1024 bytes) is sent from the host computer.
When transmitting (byte) to an IC card, the host computer divides this data into block size units and transmits them.

On the other hand, the following procedure was used to transmit data from the IC card to the host computer.

FIG. 6 is a flowchart showing the transmission procedure when transmitting data from the IC card to the host computer.

When the IC card receives a hard reset command from the host computer via the reader/writer, it performs a hard reset (step Sl). Next, the IC card receives ATR information (Answer to Re) including its block size (determined by its communication buffer), etc.
5et) to the host computer via the reader/writer (step S2).

The host computer and reader/writer that have received the ATR information perform subsequent communications using this block size as the unit of data transmission.

Next, when a data request command is received from the host computer via the reader/writer (step S3), the size of the data to be transmitted included in the command is determined based on this block size (communication buffer size). (Step S4).

If the transmitted data is data whose size does not exceed the block size, step S9, which will be described later, is executed.

If the data to be transmitted exceeds this block size (YES at S4), this data is divided into this block size (step S5).

Next, the IC card (its CPU) checks whether it has received a read command via the reader/writer (
Step S6).

When the data request command is received, a chain code is added to the created divided data to notify the existence of the next divided data to be transmitted, and the chain code is transmitted to the reader/writer and further to the host computer (step S7).

Next, the IC card determines whether the divided data remains in its memory (step S8), and if so, returns to S6. If there is no remaining data, the data (only the final divided data or only the data that does not exceed the block size) is sent to the host computer (step S9), and then a termination response is sent (step 5).
10).

<Problem to be Solved by the Invention> However, in such a conventional IC card communication system, data communication between the IC card and the host computer is determined by, for example, the capacity of the IC card's human output buffer. Data is exchanged in units of a fixed block size. However, the reader/writer transfers divided data (data divided into block size units) from the host computer to the IC card, and
It was only an intermediary from the C card to the host computer. In other words, with conventional reader/writers,
It was not possible to combine data in block size units.

In such a conventional communication system using a reader/writer, when sending divided data from an IC card to a host computer via the reader/writer, the reader/writer is sent every time one unit of divided data is sent to the host computer. A response signal was received from the host computer via the writer. As a result, when the amount of data transmitted from the IC card is large, that is, when the number of divided data is large, the number of communications between the host computer and reader/writer and the IC card increases. For this reason, I.C.
This resulted in a decrease in communication efficiency between the card and the host computer.

SUMMARY OF THE INVENTION An object of the present invention is to provide an IC card communication system that improves data communication efficiency between an IC card and a host computer.

Means for Solving the Problems> The present invention includes a host computer, an IC card that performs data communication with the host computer, and a reader/writer that controls data communication between these,
In an IC card communication system in which an IC card and a reader/writer perform data communication in units of a predetermined block size, the reader/writer has a storage means having a memory capacity larger than the block size, and a memory device that reads this block from the IC card. Read data in size units,
an IC comprising a communication control means for combining a plurality of pieces of data in block size units and transmitting the combined data to a host computer;
It is a card communication system.

<Operation> In the present invention, when the host computer reads data from the IC card via the reader/writer, the communication control means of the reader/writer receives the data from the IC card in block size units, and then reads the data. is once stored in the storage means, and then a plurality of stored block size units of data are combined and sent to the host computer as data of a predetermined size. For example, the data may be sent in bulk to the host computer.

<Embodiment> FIG. 1 is a block diagram showing the configuration of an IC card communication system according to an embodiment of the present invention.

In the figure, 21 is a host computer, 22 is an I
23 indicates a C card, and 23 indicates a reader/writer.

The host computer 21 exchanges data (information dedicated to the IC card) with the reader/writer 23 via an interface (for example, R5232C), and performs various processes based on the data.

The IC card 22 has a built-in 8-bit CPU, a 16-64 bit IC memory, an external connection terminal, etc., and exchanges information with the reader/writer 23 via the external connection terminal.

The reader/writer 23 includes a communication control means 24, such as a CPU, that controls data communication between the IC card 22 and the host computer 21, and a storage means 25, such as a memory, for storing data. Note that the memory capacity of this memory 25 is larger than the block size of the IC card 22 described below. For example, it has a memory capacity of 5 to 5 bytes.

In such a configuration, the reader/writer 23 has a power supply,
Supplying clock signals, control signals, etc. to the IC card 22,
Reading data from the IC card 22 based on a prearranged protocol, or reading the data from the IC card 22 based on a prearranged protocol
Data is being written to 2.

In this case, the data is transmitted or received after being divided into IC card block size units (a fixed block size unit defined by the capacity of the person's output buffer 7, etc., for example, 256 bytes).

FIG. 2 is a data configuration diagram showing an example of data with a block size of 256 bytes.

In the same figure, data 31 with a block size of 256 bytes is 5TX32 of 1 byte indicating the start of the block.
, a 1-byte code section 33 indicating the type of command or response
, an accompanying 2-byte address field 34, a 250-byte data field 35 for writing or reading, and a 1-byte LRC 36 for parity checking.

The program executed by the communication control means 24 of the reader/writer 23 in the IC card communication system having the above configuration will be explained based on the flowcharts shown in FIGS. 3 to 5.

FIG. 3 is a flowchart showing the communication main routine in the communication control means 24 according to this embodiment.

First, when the reader/writer 23 is powered on, the host computer 21 sends a hard reset command. The reader/writer 23 that received this hard reset command
The CPU hard resets its own communication control means (CPU) 24 (step 511) and waits for the IC card 22 to be inserted.

When the IC card 22 is inserted, the reader/writer 23 supplies power and a clock signal to the IC card 22, and also gives a reset signal to initialize the IC card 22.

The initialized IC card 22 transmits ATR information including information such as block size to the reader/writer 23.

The communication control means 24 that has received this ATR information sets a block size for data communication (step 512), and further transmits this ATR information to the host computer 21.

Then, the host computer 21 that received the ATR information
determines whether to cause the communication control means 24 to execute a write process or a read process, and transmits a command signal (WRITE command or READ command) to the reader/writer 23. In the case of writing, the host computer 21 transmits data of a predetermined size to the reader/writer 23 together with this command signal. In the case of reading, read data of a predetermined size is transmitted together with a command signal.

The communication control means 24 receives the command signal (step 513), determines the command signal (step 514),
If it is a WRITE command, execute the write subroutine (step 515), and if it is a READ command, execute the read subroutine (step 818).
.

The write subroutine will now be explained.

FIG. 4 is a flowchart showing the processing procedure of the write subroutine in the communication control means 24 according to an embodiment of the present invention.

First, the communication control means 24 receives write data from the host computer 21 and temporarily stores it in the memory 25 (step 521).

Next, the communication control means 24 determines the data size of the write data (step 522). As a result of this judgment,
If the data size of the write data does not exceed the block size of the IC card, step S27 is executed.

On the other hand, if the write data exceeds the block size of the IC card, this data is retrieved from the memory 25,
After dividing the IC card into a plurality of blocks in block size units and assigning division numbers, the data is stored in the memory 25 again in the order of the division numbers (step 523). For example, if the block size of the IC card is 256 bytes (the data part is 250 bytes) and the write data is IK pie) = 1024 bytes, it will be divided into 5 parts. Hereinafter, the data divided into communication block sizes with the IC card will be referred to as divided data.

Next, the communication control means 24 transmits one piece of divided data and the chain code to the IC card 22 (step 52
4). Note that the chain code is a code that notifies the existence of divided data to be transmitted next. Further, this divided data is transmitted in the order of the divided numbers.

Next, the IC card 22 that has received one piece of divided data and the chain coat added thereto stores the divided data in the memory (EEPROM) and transmits a data request response to the reader/writer 23.

Thereafter, when the communication control means 24 receives the data request response (step 525), it determines whether the next divided data to be transmitted is the last divided data (step 52).
6). As a result, if there is divided data to be transmitted next, the process returns to step S24 and the divided data and chain code are transmitted.

As a result of step 526, if there is no divided data to be transmitted next, only the divided data or only the data that does not exceed the block size is transmitted to the IC card 22 (step 5
27).

Next, the IC car F'22 stores only the divided data or
When only data that does not exceed the block size is received, it is stored in the memory and a termination response is sent to the reader/writer 23.

When the communication control means 24 receives the end response (step 528), it transmits the end response to the host computer 21 (step 529), and returns to the main routine program.

Next, the read subroutine will be explained.

FIG. 5 is a flowchart showing the processing procedure of the read subroutine in the communication control means 24 according to one embodiment.

First, the communication control means 24 transmits a data request command to the IC card 22 (step 531).

When the IC card 22 receives the data request command,
If there is multiple block size data to send, 1
Data of one block size and the chain code attached to it are sent, and if it is a single piece of data, only that data is sent.

If there is data of multiple block sizes to be transmitted, after the first block is transmitted, the pointer moves to the beginning of the next block.

When the communication control means 24 receives the read data (step 532), it stores the read data in the temporary memory 25 (step 533), and then checks whether there is a chain code, that is, whether there is divided data to be transmitted next. (step 534). As a result of the determination, if there is divided data, the communication control means 24 returns to step 531 and transmits a data request command.

On the other hand, if there is no divided data, the divided data and all the divided data stored in the memory 25 are matched and combined as read data, and then the host computer 25
1 (Step 535), the program returns to the main routine.

These subroutine processes (step S15゜518)
After the completion of step 51, the communication control means 24 determines whether there is next write data in the host computer 21 or read data in the IC card 22.
6, 519), if there is next write data, the process returns to step 515 and executes the write subroutine. If there is next read data, the process returns to step S18 and the read subroutine is executed.

If there is no next write data or read data, the communication control means 24 controls the host computer 2I.
Step 517)
, if communication is to be continued, the process returns to step S13 and a command signal is received.

If communication is not to be continued, the main program is terminated.

As described above, in this communication system, when transmitting data from the IC card 22 to the host computer 21 via the reader/writer 23, the reader/writer 23 once reads all divided data from the IC card 22, and then , - transmit all divided data to the host computer 21 at once. Therefore, the number of times of communication between the host computer 21 and the reader/writer 23 is only one, and communication efficiency is dramatically improved.

Further, in this communication system, when the data from the host computer 21 exceeds the block size of the IC card 22, the communication control means 24 of the reader/writer 23 temporarily stores the data in the memory 25, and then transfers the data to the IC card 22.
It is divided into two block sizes and transmitted sequentially. Therefore, even the host computer 21, which does not have a means for dividing data into the block size of the IC card 22 and sequentially transmitting the data, can write data to the IC card 22.

Furthermore, when the data size to be written from the host computer 21 to the IC card 22 via the reader/writer 23 is large, the reader/writer 23 temporarily stores this data in the memory 22.
After storing the data into the IC card 22, the data is divided into block sizes and sequentially transmitted to the IC card 22 as divided data. Therefore, the number of times of communication between the host computer 21 and the reader/writer 23 is only one, thereby improving communication efficiency.

<Effects> As described above, according to the present invention, it is possible to improve communication efficiency between a host computer and an IC card.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an IC card communication system according to an embodiment of the present invention, FIG. 2 is a data configuration diagram showing an example of data with a block size of 256 bytes, and FIG. 3 is a block diagram showing the configuration of an IC card communication system according to an embodiment of the present invention. FIG. 4 is a flowchart showing a communication procedure in a communication control means according to an embodiment of the present invention, FIG. A flowchart showing the processing procedure of the read subroutine in the communication control means according to the embodiment. FIG. 6 is a flowchart showing the procedure when data is transmitted from a conventional IC to a reader/writer. 21...Host computer, 22...
・ ・ ・ ・ ・ IC card, 23...
・Reader/writer, 24...CPU (communication control means), 25.
...Memory (storage means).

Claims (1)

[Claims] The IC card includes a host computer, an IC card that performs data communication with the host computer, and a reader/writer that controls data communication between them, and the IC card and the reader/writer are arranged in a predetermined manner. In an IC card communication system that performs data communication in units of block size, the reader/writer has a storage means having a memory capacity larger than the block size, reads data from the IC card in units of this block size, and reads data from the IC card in units of this block size. 1. A communication system for an IC card, comprising: communication control means for combining a plurality of pieces of data in block size units and transmitting the combined data to a host computer.