JPH05314011A - Ic card - Google Patents

Abstract

PURPOSE:To make the use of an IC card more convenient by protecting easily and surely data when the data is desired to be protected from the decoding, the alteration, or the rewriting of the data by the operation of another person. CONSTITUTION:An IC chip 6 provided with a function to generate a signal for judging a write protection state, and simultaneously, execute protection about the write-in of the data to the IC card 2 by judging the write protection state in accordance with whether the signal is inputted or not is mounted on a card substrate 4. This IC chip 6 is provided with an output port 14 to output the signal to the outside and an input port 16 to fetch this signal from the outside. Wiring 18 to connect both the ports 14, 16 is provided on the card substrate 4. The state of write protection is judged by the presence of the disconnection of this wiring 18.

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 being protected from acts such as falsification and rewriting of data by an external operation, that is, so-called write protection.

[0002]

2. Description of the Related Art An example of a conventional method for such write protection will be described. In the conventional IC cards, a collation such as a password is used to determine whether it is possible or impossible to access the data stored in the internal memory and perform an operation such as rewriting. The IC card is attached to the IC card reader / writer, and the password is input to the reader / writer, and it is determined whether or not the passwords match by a software method. If the verifications match, the IC card IC attached to the reader / writer
Some cards allow the above-mentioned operations by the reader / writer to be enabled, and if they do not match, protect the data in the memory, that is, write protect. These are software-like ones, and are not ones that enable write-protection by hardware-like means such as some kind of physical treatment of an IC card.

[0003]

Even if the IC card has the same structure in terms of hardware, it can be used for different purposes depending on the application software incorporated therein, so that many application softwares are applied and IC cards are used for various purposes. Now that cards are being used, the IC is not used for password verification as described above.
It is highly possible that another application system, which is completely different from the application software installed on the card corresponding to the intended use, is mistakenly used and the data is rewritten, and that the password is known to others. The internal data may be tampered with or rewritten.

When data rewriting is managed by password verification by application software, for example, only the person who knows the password can rewrite it, and the person who does not know the password cannot rewrite the data. Therefore, as a user who uses the application software legally from the application software provider but does not know the password to rewrite the data, the user can write protect to another third party or invalidate the card. There is no way to do it by oneself, which is rather inconvenient when using an IC card.

Therefore, in the present invention, data protection can be arbitrarily performed by anyone who owns the IC card, as well as password protection given to a specific person, and operation by another person. The purpose of the present invention is to make the use of an IC card more convenient by easily and surely protecting data when it is desired to protect it from manipulation such as falsification or rewriting of data.

[0006]

In order to achieve such an object, in the IC card of the present invention, a write protect signal for determining the write protect state is generated and whether or not the signal is input. An output port for outputting a signal to the functional component on the card substrate, the functional component having a function of determining the write protect state according to whether to protect the IC card from writing data. And an input port for receiving this signal from the outside, and wiring for connecting both ports is provided on the card board.
It is characterized in that the state of write protection can be determined by the functional component depending on whether or not the signal from the output port is input through the input port depending on whether or not the wiring is cut.

[0007]

When the wiring between the input port and the output port is not cut, the write protect signal for determining the write protect state generated from the functional component is output from the output port and then input to the input port. Therefore, the functional component determines that the IC card is not in the write protect state, and can rewrite the data in the IC card. Further, when the wiring is disconnected, the signal is not taken in from the input port. Therefore, the functional component determines that the IC card is in the write protect state, and as a result, rewrites the data for the IC card. Can not be.

Therefore, when the wiring is disconnected, the internal data will not be tampered with or rewritten, and the data can be rewritten even if it is erroneously applied by another application system. Absent. Further, for example, a means for performing write protection is also provided to a user who uses the application software legally provided by the application software provider but does not know the password for rewriting the data, which is useful for using the IC card. It is convenient.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a plan view of an IC card according to an embodiment of the present invention, and FIG. 2 is a circuit diagram of its main part. In the figure, the IC card 2 has an IC chip 6 as a functional component mounted on a card substrate 4. The IC chip 6 includes a CPU 8, a ROM 10, and an EEPROM.
12 and the like, and in the CPU 8 thereof, R
It controls the execution of various functions as an IC card according to the program in the OM10 and
A write protect signal generator 8a for generating a write protect signal for determining the write protect state for write protect of the data stored in M12, and whether or not the write protect signal is input. It functionally has a write protect state determination unit 8b that determines the write protect state.

The I mounted on the card substrate 4 in this way
The C chip 6 is provided with an output port 14 for outputting the write protect signal to the outside and an input port 16 for taking in the write protect signal from the outside, and the output port 14 is provided for the write protect signal generator 8a of the CPU 8.
Similarly, the input ports 16 are also connected to the write protect state determination unit 8b of the CPU 8, respectively.

A conductive wire 18 is provided on the card board 4, and the output port 14 and the input port 16 are connected by the wire 18. The wiring 18 may be embedded inside the card substrate 4, or may be printed on the surface with a conductive ink.

The power supply receiving section 8c of the CPU 8 which receives power from the power supply terminal 20 of the IC card 2 and the write protect state determining section 8b are connected via a resistor 22. When the write protect signal generating section 8a outputs a low level when not being cut along the line AA, the input potential to the write protect state determining section 8b becomes a low level through the wiring 18, thereby The write protect state determiner 8b determines that the IC card 2 is not in the write protect state, and when the wiring 18 is cut along the line AA, the write protect state determiner 8b via the resistor 22. Since the input potential to 8b is at high level by the power source from the power source terminal 20, State determination unit 8b is the IC card 2
Is determined to be in the write protect state.

Therefore, when the wiring 18 between the input port 14 and the output port 16 is not cut as described above, the write protect signal generator 8 of the CPU 8
The write protect signal generated from a is output from the output port 14 of the IC chip 6 and then taken into the input port 16 via the wiring 18, and is input to the write protect state determination unit 8b of the CPU 8. Therefore, the CPU 8 determines that the IC card 2 is not in the write protect state and enables rewriting of the data in the IC card 2.

On the other hand, when the wiring 18 is cut off, the write protect signal is not taken into the write protect state judging section 8b of the CPU 8 via the input port 16, so that the CPU 8 writes the IC card 2 in the write protect state. It is determined that the IC card 2 is in the state, and the IC card 2 cannot be rewritten.

As an example of using this IC card,
An IC card interface device is installed in a pay broadcast receiver or personal radio that requires an identification code unique to the device. When selling this pay broadcast receiver or personal radio, the IC card with the unique identification code is sold. After the store writes the expiration date and the like, the device is a write protect of the present invention, and the device for cutting the wiring cuts it, and then the IC card is attached to the receiver or the wireless device. Since it has the identification code, it is impossible for the user to tamper with the data of the IC card.

[0017]

As is apparent from the above description, according to the present invention, when the wiring between the input port and the output port is not cut, the write protect signal from the functional component is output from the output port. After that, it is determined that the functional component is not in the write protect state by this, and it is possible to rewrite the data in the IC card, and when the wiring is disconnected. , The signal is not taken in from the input port, it is judged that the functional component is in the write protect state, and it is made impossible to rewrite the data to the IC card, so wiring is different from the conventional password. Other application software is wrongly applied just by disconnecting or not,
It is possible to easily prevent the internal data from being tampered with or rewritten. For example, the data is rewritten when the application software is legally used and the application software is used. A means to perform write protection is provided to users who have not been notified of the password.
It is very convenient to use the IC card.

[Brief description of drawings]

FIG. 1 is a plan view of an IC card according to an embodiment of the present invention.

FIG. 2 is a circuit diagram inside the IC card.

[Explanation of symbols]

 2 IC card 4 Card board 6 IC chip (functional part) 8 CPU 8a Write protect signal generator 8b Write protect state judgment unit 14 Output port 16 Input port 18 Wiring

Claims (1)

[Claims] 1. A write protect signal for determining a write protect state is generated, and a write protect state is determined according to whether or not the signal is input to protect data writing to the IC card. An output port (14) for outputting a signal to the functional component (6) to the outside, and an input port for fetching the signal from the outside, provided with a functional component (6) having a function of performing on the card substrate (4) (16) and both ports (14, 1) are provided on the card board (4).
6) A wiring (18) for connecting the two is provided, and this wiring (1
According to the presence or absence of disconnection of 8), the signal from the output port (14) of the functional component (6) is input to the input port (16).
An IC characterized in that the state of write protection can be determined according to whether or not it is input via
card.