JPH09102789A - Data communication device - Google Patents

Abstract

(57) [Abstract] [Problem] When communicating between a master station and a plurality of slave stations,
Surely prevent interference. A memory 7 of an IC card 2 stores a card number different from other IC cards 2 in addition to an ID number. When the IC card 2 receives the identification number request signal from the card reader 1, the IC card 2 transmits the ID number at a unique communication timing corresponding to the stored card number. As a result, the card reader 1 can read the ID numbers of all the IC cards 2 without interference. Then, the card reader 1 communicates with a specific IC card 2 of the plurality of IC cards 2 based on the read ID number.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to communication between a master station and a slave station (contactless tag), and more particularly to a data communication device for identifying a plurality of slave stations and performing data communication.

[0002]

Conventionally, in communication between a master station and a slave station (contactless tag) using weak radio waves, the master station and the slave station have a one-to-one relationship. It controlled and polled the slave station from the master station to communicate.

However, when a plurality of slave stations are located within the monitoring range of the master station, there is a problem that the slave station's response to the polling from the master station collides, and proper communication cannot be performed. .

Therefore, as means for solving the above problem, (1) an ID number (identification number) is registered in advance in the slave station, and the master station reads and reads the ID numbers from the slave stations sequentially located in the monitoring range. Communication with a specific slave station based on the ID number. (2) A random number is generated in the slave station, and communication with the master station is executed at a communication timing according to the random number.

However, in the above method (1), I
If the timings of reading the D number overlap, it becomes impossible to read the ID number, or the ID number changes and communication based on the ID number cannot be executed. Further, in the above method (2), since communication is performed at a timing based on the probability of random numbers, the probability of interference increases as the number of slave stations increases and the time spent for interference prevention decreases. It becomes high, and after all, interference cannot be completely prevented.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a data communication apparatus capable of reliably preventing interference when communicating between a master station and a plurality of slave stations. To provide.

[0007]

The present invention provides a data communication apparatus for performing data communication between a master station and a slave station having a unique identification number located within the monitoring range of the master station. Transmits an identification number request signal intermittently toward the monitoring range, and a slave station located in the monitoring range is assigned a unique slave station number and receives an identification number request signal from the master station. In this case, the identification number set for itself is transmitted at a unique timing corresponding to the assigned slave station number, and the master station is located in the monitoring range based on the identification number read from the slave station. Communication with a specific slave station among a plurality of slave stations is executed (Claim 1).

In such a configuration, when the plurality of slave stations located within the monitoring range simultaneously receive the identification number request signal transmitted from the master station, the slave stations corresponding to the assigned slave station numbers are unique. At that timing, the identification number set for itself is transmitted. This allows the master station to read the identification numbers of a plurality of slave stations without interference. Then, the master station executes communication with a specific slave station among the plurality of slave stations located in the monitoring range based on the identification number read from the slave station.

Further, the master station sequentially transmits an identification number request signal to which the slave station number assigned to the slave station is added toward the monitoring range, and the slave stations located in the monitoring range have their own slaves. When the station number is assigned and the identification number request signal with the slave station number added is received from the master station, the identification number set for itself is transmitted at a unique timing corresponding to the slave station number, The master station may execute communication with a specific slave station among a plurality of slave stations located in the monitoring range based on the identification number read from the slave station (claim 2).

In such a configuration, when a plurality of slave stations located within the monitoring range simultaneously receive the identification number request signal transmitted from the master station, they correspond to the slave station number added to the identification number. The identification number set for itself is transmitted at the unique timing. This allows the master station to read the identification numbers of a plurality of slave stations without interference.

Then, the master station executes communication with a specific slave station among a plurality of slave stations located in the monitoring range based on the identification number read from the slave station.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment in which the present invention is applied to a commuter pass will be described below with reference to FIGS. FIG. 1 shows the overall system configuration. In this FIG.
The card reader 1 as a master station is installed at the ticket gate so as to perform data communication with the IC card 2 as a slave station located in the monitoring range. That is,
The IC card 2 is provided with an antenna 3, a receiving unit 4 and a transmitting unit 5, and when the operating power is supplied by electromagnetic coupling with the card reader 1, the IC card 2 is powered on and radio waves are transmitted between the IC card 2 and the card reader 1. To communicate.

The memory control unit 6 controls the memory 7 based on the reception result of the reception unit 4. The memory 7 stores a card number (slave station number), an ID number (identification number), application information and the like.

The transmission timing determination unit 8 determines the transmission timing unique to the IC card 2 based on the card number stored in the memory 7. Then, the transmission control unit 9 transmits the ID number stored in the memory 7 to the transmission unit 5 according to an instruction from the transmission timing determination unit 8.

FIG. 2 shows the file information stored in the memory 7, and all of this information is encrypted. Here, commuter pass basic information and option information are set as file information. As the commuter pass basic information, a card number, a card ID, an issue date, a company code, a boarding station, a transit station, an expiration date, a type, and a user attribute are stored.

Here, the card number means a serial number assigned to all IC cards 2 carried by one user, and usually one user owns a maximum of 5 IC cards 2. One of the numbers 1 to 5 is assigned on the assumption that That is, the card number of the IC card 2 owned by one person is set so as not to overlap. The card ID is a number that is set to be different for each IC card 2, and the number of digits for the total number of issued commuter passes is set. Further, a ticket gate history and settlement information are set as option information. As the ticket gate history, the ticket gate time, type, and ticket gate station are stored. In addition, the payable amount is stored as the settlement information.

Next, the operation of the above configuration will be described. In this case, when commuting by connecting multiple routes (JR, private railway, etc.) from home to the office, multiple IC cards 2 functioning as commuter passes are required for each route,
It is sufficient to assume that a maximum of five IC cards 2 are carried. Now, for example, when issuing an IC card 2 to a passenger who needs the maximum number of five IC cards 2, a different card number from 1 to 5 is added to the five IC cards 2. Is stored in the memory 7 of the IC card 2.

Then, the passenger carrying the IC card 2
When passing through the ticket gate, all IC cards 2 carried (which are usually stored in a commuter pass and in close contact with each other) are opposed to the card reader 1 installed at the ticket gate. Here, in FIG. 3 showing the operation of the card reader 1, the card reader 1 intermittently wirelessly transmits an ID response request signal from an antenna (not shown) (step A1).

When the IC cards 2 face the card reader 1, all IC cards 2 receive the ID response request signal from the card reader 1. At this time,
In FIG. 4 showing the operation of the IC card 2, the IC card 2
When a command is received from the card reader 1 (step B1), it judges whether the command is an ID response request signal (step B2).

In this case, since the command is the ID response request signal, all IC cards 2 wait until the time slot corresponding to the card number (step B3),
The ID number stored in the memory 7 is returned. That is,
The IC card 2 having the card number "1" has the time slot No. 1 shown in FIG. 1 returns the ID number, and the IC card 2 having the card number "2" is the time slot No. 2 in ID
The IC card 2 whose card number is “3” is returned as the time slot number. 3, the ID number is returned, and the IC card 2 having the card number “4” is the time slot number. I in 4
The IC card 2 which returns the D number and the card number is "5" is the time slot number. The ID number is returned at 5.

As a result of the above operation, the card reader 1 sequentially reads the ID numbers from the plurality of IC cards 2 simultaneously located in the monitoring range at different timings (step A3 shown in FIG. 3), and as shown in FIG. ID of each IC card 2
The number can be read without interference.

After reading the ID numbers from all the IC cards 2, the card reader 1 confirms the authenticity of the ID numbers, and then performs data communication with a specific IC card 2 as necessary. That is, when communicating with the IC card 2 having the card number "1", the ID number of the card number "1" is added to the command and transmitted (step A4).

Then, the IC card 2 is the card reader 1
When the command is received from the command, it is determined whether the ID number added to the command matches the ID number stored in the memory 7 (step B5 in FIG. 4). If they match, the command is the read command. It is determined whether or not (step B6). At this time, if the command is a read command, the predetermined read data read from the memory 7 is returned (step B7). As a result, the read data is transmitted from the IC card 2 having the card number “1” to the card reader 1.

On the other hand, the card reader 1 which has transmitted the read command determines whether or not there is a response from the IC card 2 before the time-out (steps A5 and A in FIG. 3).
6). At this time, before the time out, IC card 2
Since the read command is transmitted from, the process returns to step A4, and the command is added with the ID number of "2" and transmitted. As a result, the read data is transmitted from the IC card 2 having the card number “2” to the card reader 1.
Then, the card reader 1 performs all I
When communication with the C card is executed and the communication is completed (step A7), the process returns to step A1.

According to the above structure, one IC card 2 functions as all commuter passes carried by one user.
When the IC card 2 transmits its own ID number to the card reader 1 by previously allocating different card numbers of ~ 5 to each other, the ID number is transmitted at a unique communication timing corresponding to the time slot corresponding to the allocated card number. Therefore, unlike the conventional example in which the ID number is simply stored in the slave station or the communication is executed at the communication timing corresponding to the random number, the card reader 1 is provided for the plurality of IC cards 2 simultaneously located in the monitoring range. The ID number can be reliably read, and subsequent communication with the IC card 2 can be reliably performed based on the ID number.

7 to 10 show a second embodiment of the present invention, and since the basic structure is the same as that of the first embodiment, its explanation is omitted. In the second embodiment, the card reader 1
Is to transmit the card number to the IC card 2, and the IC card 2 returns the identification number at a unique communication timing corresponding to the transmitted card number.

That is, in FIG. 7 showing the operation of the card reader 1, the card reader 1 sets the card number to "1" (step C1) and transmits an ID response request signal to which the card number "1" is added. And then (Step C
2) Then, 1 is added to the card number (step C3), and it is monitored whether or not there is an ID response request signal before the time-out (steps C4 and C5).

In this case, FIG. 8 showing the operation of the IC card 2
In the case where the IC card 2 located in the monitoring range receives a command from the card reader 1 (step D
1), it is determined whether the command is an ID response request signal (step D2). At this time, the received command is ID
Since it is a response request signal, it is determined whether or not the card number added to this ID response request signal matches the ID number assigned to itself (step D3).

Here, the IC card 2 with the card number "1"
Judges that the transmitted card number "1" matches the card number "1" assigned to itself, and therefore returns the ID response signal (step D4). The card reader 1 which has read the ID number of the card number "1" as described above
Transmits an ID response request signal to which the IC card number "2" is added, this time, the ID number can be read from the IC card having the card number "2" as shown in FIG.

As a result of repeating the above-described operation, the card reader 1 sequentially reads the ID numbers from the plurality of IC cards 2 at different timings. Therefore, as shown in FIG.
The ID number of the card 2 can be read without interference.

Then, the card reader 1 that has read the ID numbers from all the IC cards 2 adds the ID numbers such as a read command and transmits the same as the specific IC card 2 as in the first embodiment. Execute communication. As a result of the above operation, the card reader 1 is
Communication can be performed without interference with the C card 2.

The present invention is not limited to the above embodiment, but can be modified or expanded as follows. The card number stored in the memory 7 of the IC card 2 is not limited to 1 to 5, and may be 6 or more, and need not be a serial number. Data communication may use magnetic coupling.

[0033]

As is apparent from the above description, according to the data communication device of the present invention, when the slave station is assigned a unique slave station number and the master station reads the identification number from the slave station, the slave station Since the identification number is read at a unique communication timing according to the slave station number assigned to the mobile station, interference can be reliably prevented when communicating between the master station and a plurality of slave stations. It has an excellent effect.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an overall configuration in a first embodiment of the present invention.

FIG. 2 is a diagram showing various kinds of information stored in a memory of an IC card.

FIG. 3 is a diagram showing an operation of a card reader.

FIG. 4 is a diagram showing an operation of an IC card.

FIG. 5 is a timing diagram showing communication between a card reader and an IC card.

FIG. 6 is a processing flow showing communication between a card reader and an IC card.

FIG. 7 is a view corresponding to FIG. 3, showing a second embodiment of the present invention;

FIG. 8 is a view corresponding to FIG.

FIG. 9 is a diagram corresponding to FIG. 5;

FIG. 10 is a view corresponding to FIG.

[Explanation of symbols]

Reference numeral 1 is a card reader (master station), IC card (slave station), and 7 is a memory.

Claims (2)

[Claims] 1. A data communication device for performing data communication between a master station and a slave station having a unique identification number located in the monitoring range of the master station, wherein the master station is directed toward the monitoring range. The slave station that transmits the identification number request signal intermittently is assigned a unique slave station number to the slave station located in the monitoring range, and when it receives the identification number request signal from the master station, the slave station The identification number set to itself is transmitted at a unique timing corresponding to the station number, and the master station identifies the plurality of slave stations located in the monitoring range based on the identification number read from the slave station. A data communication device for performing communication with a slave station of the data communication device. 2. A data communication device for performing data communication between a master station and a slave station having a unique identification number located in the monitoring range of the master station, wherein the master station is directed toward the monitoring range. Sequentially transmitting an identification number request signal to which the slave station number assigned to the slave station is added, the slave station located in the monitoring range is assigned a unique slave station number, and the slave station number from the master station is When receiving the added identification number request signal, it transmits the identification number set to itself at a unique timing corresponding to the slave station number, the master station, based on the identification number read from the slave station. A data communication apparatus, which executes communication with a specific slave station among a plurality of slave stations located in the monitoring range.