JP7424536B1 - Electronic information storage medium, IC chip, IC card, communication parameter transmission method, and program - Google Patents

Abstract

The present invention provides an electronic information storage medium, an IC chip, an IC card, a communication parameter transmission method, and a program that can present two types of communication parameters corresponding to two types of standby states to an external device. [Solution] An IC chip 1 transmits information indicating a communication parameter CPI to an external device 2 by a response signal when starting communication from an IDLE state, and indicates a communication parameter CPH when starting communication from a HALT state. The information is transmitted to the external device 2 by a response signal. [Selection diagram] Figure 8

Description

The present invention relates to a technical field such as a contactless IC (Integrated Circuit) card that can perform contactless communication with an external device.

Conventionally, two types of standby states, IDLE state and HALT state, are known as states in which a non-contact IC card conforming to ISO/IEC14443-3 waits for communication with an external device. For example, when a Type-B contactless IC card starts communicating with an external device in the IDLE or HALT state, it uses pre-stored communication parameters in response to WUPB (Wake UP command Type B) from the external device. The information is sent to an external device using ATQB (Answer To reQuest for PICC B). For example, the contactless IC card disclosed in Patent Document 1 stores a plurality of communication conditions including an initial communication condition, and by switching these plurality of communication conditions on the contactless IC card side, the communication method It is possible to communicate with multiple communication terminals with different types.

Japanese Patent Application Publication No. 2008-276572

However, in the conventional technology including Patent Document 1, the external device changes the communication parameters (for example, maximum frame size, etc.) when starting communication with the contactless IC card from IDLE state and when starting communication from HALT state. cannot be switched.

Therefore, the present invention has been made in view of these points as an example of the problem, and provides an electronic information storage medium that can present two types of communication parameters corresponding to two types of standby states to an external device. , an IC chip, an IC card, a communication parameter transmission method, and a program.

In order to solve the above problem, the invention according to claim 1 provides an electronic information storage medium capable of communicating with an external device, the electronic information storage medium changing from a first standby state in which communication with the external device is waited. Information indicating a first communication parameter when starting the communication, and a second standby state in which communication with the external device is waited, which is different from the first standby state, and the communication is started from a second standby state different from the first standby state. a storage means for storing information indicating a second communication parameter when starting the communication; and a storage means for storing information indicating the first communication parameter when starting the communication from the first standby state; An electronic information storage medium comprising: transmitting means for transmitting information indicating the second communication parameter to the external device when starting the communication from a second standby state.

The invention according to claim 2 is the electronic information storage medium according to claim 1, wherein the information indicating the communication parameter includes at least one of a maximum frame size, a maximum waiting time, and a communication speed. It is characterized by including information indicating.

According to a third aspect of the invention, in the electronic information storage medium according to the first aspect, the information indicating the first communication parameter includes information indicating the first standby state, and the information indicating the second communication parameter is characterized in that it includes information indicating the second standby state.

The invention according to claim 4 is the electronic information storage medium according to any one of claims 1 to 3, wherein the communication is contactless communication, the first standby state is an IDLE state, and the first standby state is an IDLE state. 2. The standby state is characterized in that it is a HALT state.

The invention according to claim 5 is an IC chip capable of communicating with an external device, and the first communication when starting the communication from a first standby state of waiting for communication with the external device. Information indicating a parameter and a second communication parameter when starting communication from a second standby state in which communication with the external device is waited and is different from the first standby state. a storage means for storing information, and transmitting information indicating the first communication parameter to the external device when starting the communication from the first standby state, while starting the communication from the second standby state. and transmitting means for transmitting information indicating the second communication parameter to the external device in the case where the communication parameter is the second communication parameter.

The invention according to claim 6 provides an IC card capable of communicating with an external device, wherein the first communication is performed when starting the communication from a first standby state in which communication with the external device is waited. Information indicating a parameter and a second communication parameter when starting communication from a second standby state in which communication with the external device is waited and is different from the first standby state. a storage means for storing information, and transmitting information indicating the first communication parameter to the external device when starting the communication from the first standby state, while starting the communication from the second standby state. and transmitting means for transmitting information indicating the second communication parameter to the external device in the case where the communication parameter is the second communication parameter.

The invention according to claim 7 provides a communication parameter transmission method executed by an electronic information storage medium capable of communicating with an external device, the method comprising: starting from a first standby state of waiting for communication with the external device; Information indicating a first communication parameter when starting the communication, and a second standby state in which communication with the external device is waited, which is different from the first standby state, and the communication is started from a second standby state different from the first standby state. storing information indicating a second communication parameter when starting the communication; and transmitting information indicating the first communication parameter to the external device when starting the communication from the first standby state; The method is characterized in that it includes the step of transmitting information indicating the second communication parameter to the external device when starting the communication from the second standby state.

The invention according to claim 8 is a case where a computer included in an electronic information storage medium capable of communicating with an external device starts communication from a first standby state in which it waits for communication with the external device. and information indicating a first communication parameter of the external device, and a second standby state in which communication with the external device is waited for, and a second standby state in which the communication is started from a second standby state different from the first standby state. storing information indicating communication parameters; and transmitting information indicating the first communication parameters to the external device when starting the communication from the first standby state; and transmitting information indicating the second communication parameter to the external device when starting the second communication parameter.

The invention according to claim 9 is an electronic information storage medium capable of communicating with an external device, comprising a memory that stores at least information indicating default communication parameters used in communication with the external device. an electronic information storage medium provided with the electronic information storage medium, the current state of the electronic information storage medium is a first standby state in which it waits for communication with the external device, or a first standby state in which it waits for communication with the external device; a first determining means for determining whether the current state is a second standby state different from the first standby state, and the current state is determined to be the first standby state; If the current state is the second standby state, it is determined whether information indicating a first communication parameter for starting the communication from the first standby state is stored in the memory. If determined, a second determining means for determining whether information indicating a second communication parameter for starting the communication from the second standby state is stored in the memory; If it is determined that information indicating the default communication parameter is not stored in the memory, information indicating the default communication parameter is transmitted to the external device, while information indicating the first communication parameter is stored in the memory. If it is determined that the information indicating the first communication parameter is not stored in the memory, the first transmitting means transmits information indicating the first communication parameter to the external device; and if it is determined that the information indicating the second communication parameter is not stored in the memory, the default and transmitting information indicating the second communication parameter to the external device, and if it is determined that information indicating the second communication parameter is stored in the memory, transmitting information indicating the second communication parameter to the external device. A second transmitting means for transmitting data.

The invention according to claim 10 is an electronic information storage medium capable of communicating with an external device, comprising a memory that stores at least information indicating default communication parameters used in communication with the external device. A communication parameter transmission method executed by an electronic information storage medium comprising: a current state of the electronic information storage medium is a first standby state in which it waits for communication with the external device; determining whether the current state is a second standby state in which communication with an external device is waited for and which is different from the first standby state; and the current state is in the first standby state. If it is determined that there is, it is determined whether or not information indicating a first communication parameter for starting the communication from the first standby state is stored in the memory; If it is determined that the communication is in the standby state, determining whether information indicating a second communication parameter for starting the communication from the second standby state is stored in the memory; and If it is determined that information indicating the parameter is not stored in the memory, information indicating the default communication parameter is transmitted to the external device, while information indicating the first communication parameter is not stored in the memory. If it is determined that the first communication parameter is present, transmitting information indicating the first communication parameter to the external device; and if it is determined that the information indicating the second communication parameter is not stored in the memory, the default While transmitting information indicating a communication parameter to the external device, if it is determined that information indicating the second communication parameter is stored in the memory, transmitting information indicating the second communication parameter to the external device. The method is characterized by comprising the steps of:

The invention according to claim 11 is an electronic information storage medium capable of communicating with an external device, comprising a memory that stores at least information indicating default communication parameters used in communication with the external device. A computer included in an electronic information storage medium provided with the electronic information storage medium has a current state of the electronic information storage medium in a first standby state in which it waits for communication with the external device, or a first standby state in which it waits for communication with the external device. a step of determining whether the current state is a second standby state different from the first standby state in which communication is waited; and when it is determined that the current state is the first standby state; , determining whether information indicating a first communication parameter for starting the communication from the first standby state is stored in the memory; and determining that the current state is the second standby state. If the communication is started from the second standby state, determining whether information indicating a second communication parameter is stored in the memory, and information indicating the first communication parameter is stored in the memory. If it is determined that the default communication parameters are not stored in the memory, information indicating the default communication parameters is transmitted to the external device, while if it is determined that the information indicating the first communication parameters is stored in the memory. , transmitting information indicating the first communication parameter to the external device; and if it is determined that the information indicating the second communication parameter is not stored in the memory, transmitting information indicating the default communication parameter. While transmitting to the external device, if it is determined that information indicating the second communication parameter is stored in the memory, transmitting information indicating the second communication parameter to the external device. It is characterized by causing

According to the present invention, two types of communication parameters corresponding to two types of standby states can be presented to an external device.

1 is a diagram showing an example of a hardware configuration of an IC chip 1. FIG. (A) is a diagram showing an example of a memory map of a record area that stores information indicating communication parameters in the NVM 13 of the IC chip 1 that employs Type A as the communication method, and (B) is a diagram showing an example of a memory map of a record area that stores information indicating communication parameters. 2 is a diagram illustrating an example of a memory map of a record area that stores information indicating communication parameters in the NVM 13 of the IC chip 1 employing the above. FIG. 3 is a diagram illustrating an example of an ATQA encoding configuration. FIG. 3 is a diagram illustrating an example of an ATS encoding configuration. FIG. 3 is a diagram illustrating an example of an ATQB encoding configuration. FIG. 3 is a diagram showing state transitions of an IC chip 1 that employs Type A as a communication method. FIG. 3 is a diagram showing state transitions of an IC chip 1 that employs Type B as a communication method. 5 is a flowchart showing an example of communication parameter transmission processing executed by the CPU 15 of the IC chip 1. FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[1. Configuration and functions of IC chip 1]
First, with reference to FIG. 1, the configuration and functions of an IC chip 1 according to the present embodiment will be described. The IC chip 1 is an example of an electronic information storage medium that can communicate with an external device 2. The IC chip 1 is installed in, for example, an IC card such as a credit card, a cash card, or a My Number card, or a mobile device such as a smartphone. In the case of a mobile device such as a smartphone, the IC chip 1 may be mounted on a small IC card that is removable from the mobile device, or may be installed as an eUICC (Embedded Universal Integrated Circuit Card) so that it cannot be easily removed or replaced from the mobile device. It may also be mounted on a built-in board. Note that IC cards and mobile devices are equipped with antennas used for contactless communication.

FIG. 1 is a diagram showing an example of the hardware configuration of the IC chip 1. As shown in FIG. As shown in FIG. 1, the IC chip 1 includes an I/O circuit 11, a RAM (Random Access Memory) 12, an NVM (Nonvolatile Memory) 13 (an example of a storage means), a ROM (Read Only Memory) 14, and a CPU ( Central Processing Unit) 15 (an example of a computer), etc., and complies with ISO/IEC 14443, the international standard for contactless communications. Note that the IC chip 1 stores a unique UID (Unique IDentifier). The I/O circuit 11 serves as an interface with the external device 2. The IC chip 1 performs contactless communication with an external device 2 via an I/O circuit 11 and an antenna (not shown). Type A and Type B standardized by ISO/IEC 14443 will be taken as examples of communication methods related to such contactless communication. The I/O circuit 11 is connected to an antenna and includes a power supply circuit 11a, a clock generation circuit 11b, a modulation/demodulation circuit 11c, and the like. The antenna includes an antenna coil, receives a carrier wave (electromagnetic wave) emitted from the external device 2 (reader/writer), and transmits a modulated signal output from the modulation/demodulation circuit 11c as an electromagnetic wave.

The power supply circuit 11a rectifies and smoothes an induced current related to power (induced electromotive force) induced by a carrier wave received by an antenna, and supplies power to the CPU 15 and the like. The clock generation circuit 11b generates an internal clock from the induced current related to the power induced by the carrier wave received by the antenna, and outputs it to the CPU 15 and the like. The modulation/demodulation circuit 11c demodulates data from the carrier wave received by the antenna and outputs it to the CPU 15. Further, the modulation/demodulation circuit 11c modulates the data from the CPU 15 and outputs the modulated signal to the antenna. Note that examples of the external device 2 include a transaction device equipped with a reader/writer, a data writing device, and the like.

For example, a flash memory is applied to the NVM 13. Note that the NVM 13 may be an "Electrically Erasable Programmable Read-Only Memory." The NVM 13 or the ROM 14 stores an OS (Operating System), one or more applications (including the program of the present invention), and the like. The program of the present invention can be downloaded from a data writing device. By executing the OS and applications (including the program of the present invention) stored in the NVM 13, the CPU 15 can perform the first determination means, the second determination means, the transmission means, the first transmission means, and the second transmission means in the present invention. It functions as a means etc.

Further, the NVM 13 stores at least information indicating default communication parameters used in communication with the external device 2. Here, when the default communication parameters are distinguished from other communication parameters, they are hereinafter referred to as "communication parameters CPD." The communication parameter CPD is a standard communication parameter that is also stored in conventional non-contact IC cards. Note that the information indicating the communication parameter may be a value representing the communication parameter itself, or may be a bit string that can identify the communication parameter (the same applies hereinafter).

Furthermore, the NVM 13 contains information indicating communication parameters when starting communication from an IDLE state (an example of a first standby state) in which communication with the external device 2 is waited, and information indicating communication parameters with respect to communication with the external device 2. Information indicating communication parameters when starting the communication from a standby HALT state (an example of a second standby state) is stored, for example, by setting according to an external setting command. Here, communication parameters for starting communication from the IDLE state (communication parameters corresponding to the IDLE state) are hereinafter referred to as "communication parameters CPI" to be distinguished from other communication parameters. Further, communication parameters for starting communication from the HALT state (communication parameters corresponding to the HALT state) are hereinafter referred to as "communication parameters CPH" when distinguished from other communication parameters. In this way, it is possible to present to the external device 2 two types of communication parameters corresponding to the two types of standby states, IDLE state and HALT state (that is, present them at different timings). Therefore, the external device 2 appropriately selects the communication parameter that is more suitable for the external device 2 (for example, considering the communication performance of the external device 2) from among the two types of communication parameters presented at different timings. Communication can be performed with the IC chip 1.

FIG. 2A is a diagram showing an example of a memory map of a record area that stores information indicating communication parameters in the NVM 13 of the IC chip 1 that employs Type A as the communication method. FIG. 2B is a diagram showing an example of a memory map of a record area that stores information indicating communication parameters in the NVM 13 of the IC chip 1 that employs Type B as the communication method. Note that the record area is divided into a plurality of areas, and the physical addresses of each record area are different. The information (data) stored in the record area is called a record. Each record is given a record number and associated with a physical address. Each record is logically stored (for example, a record number is stored) in one or more files (for example, EF (Elementary File)), and managed by, for example, an application. Each file is given a unique SFI (Short File Identifier). Note that in FIGS. 2A and 2B, information consisting of "1" and "0" (that is, information indicating communication parameters) is merely an example.

First, in Type A, as shown in FIG. 2(A), the NVM 13 has the maximum frame size (FSC: Frame Size for proximity Card) and communication speed (DS: Divisor Send) as communication parameters CPD, CPI, and CPH. , communication speed (DR: Divisor Receive), maximum waiting time (FWT: Frame Waiting Time), start-up frame guard time (SFGT: Start-up Frame Guard Time), and information indicating each of the UID size of IC chip 1 are stored as individual records. Note that the information indicating the communication parameter CPD, the information indicating the communication parameter CPI, and the information indicating the communication parameter CPH are preferably managed by different files. For example, information indicating the communication parameter CPD is managed by a file with SFI "001", information indicating communication parameter CPI is managed by a file with SFI "002", and information indicating communication parameter CPH is managed by a file with SFI "003". It is preferable that the information be managed by the following file.

Here, each of the maximum frame size (FSC), communication speed (DS), communication speed (DR), maximum waiting time (FWT), start frame guard time (SFGT), and UID size of IC chip 1 is communicated. These are called parameter elements. Note that the communication speed (DS) is the communication speed from the IC chip 1 to the external device 2, and the communication speed (DR) is the communication speed from the external device 2 to the IC chip 1. In the example of FIG. 2(A), each element (that is, maximum frame size (FSC), communication speed (DS), communication speed (DR), maximum waiting time (FWT), ...) are different from each other. However, information indicating some elements (for example, communication speed (DS)) may be the same among the communication parameters CPD, CPI, and CPH (for example, they are all "001"), and in this case, the The information may be stored in the same record area (ie, the same address) of NVM 13. Furthermore, in the NVM 13 shown in FIG. 2(A), information indicating the standby state type (that is, IDLE state or HALT state) as an element of communication parameters CPI and CPH is stored in each record. is remembered as.

Next, in Type B, as shown in FIG. 2(B), the NVM 13 includes communication parameters CPD, CPI, and CPH, such as communication speed capacity (an example of communication speed, BRC: Bit Rate Capacity), maximum frame size ( FSC), maximum waiting time (FWT), and start frame guard time (SFGT) are stored as respective records. Also in this case, the information indicating the communication parameter CPD, the information indicating the communication parameter CPI, and the information indicating the communication parameter CPH are preferably managed by different files. Also, in the example of FIG. 2B, the information indicating each element is different among the communication parameters CPD, CPI, and CPH. However, information indicating some elements may be the same among the communication parameters CPD, CPI, and CPH, and in this case, such information may be stored in the same record area of the NVM 13. Note that the present embodiment can also support an IC chip 1 in which information indicating at least one of the communication parameter CPI and the communication parameter CPH is not stored in the NVM 13. If the information indicating at least one of the communication parameter CPI and the communication parameter CPH is not stored in the NVM 13, information indicating the communication parameter CPD is used instead. On the other hand, if information indicating both the communication parameter CPI and the communication parameter CPH is stored in the NVM 13, the information indicating the communication parameter CPD is not used, so the information indicating the communication parameter CPD may be deleted.

The information indicating the communication parameters described above is transmitted from the IC chip 1 to the external device 2 when communication with the external device 2 is started. For example, in the case of the IC chip 1 that adopts Type A as the communication method, information indicating communication parameters is transmitted while being included in ATQA (Answer To reQuest for PICC A) or ATS (Answer To Select). On the other hand, in the case of the IC chip 1 that employs Type B as the communication method, information indicating communication parameters is transmitted while being included in ATQB (Answer To reQuest for PICC B). ATQA, ATS, and ATQB are response signals (responses) to the external device 2, respectively. FIG. 3 is a diagram illustrating an example of an ATQA encoding configuration (standard format defined by ISO/IEC14443-3). For example, when IC chip 1 starts communication from the IDLE state, information indicating the size of the UID of IC chip 1 (for example, "01") among the elements included in the communication parameter CPI is bit b7 in ATQA shown in FIG. ,b8 is set. On the other hand, when IC chip 1 starts communication from the HALT state, information indicating the size of the UID of IC chip 1 (for example, "10") among the elements included in the communication parameter CPH is bit b8 in ATQA shown in FIG. ,b7 is set.

FIG. 4 is a diagram illustrating an example of an ATS encoding configuration (standard format defined by ISO/IEC14443-3). For example, when the IC chip 1 starts communication from the IDLE state, information indicating the maximum frame size (FSC) (for example, "1100") among the elements included in the communication parameter CPI is T0 ( Set in FSCI (bits b4 to b1) in the format byte). In addition, when starting communication from the IDLE state, information indicating the communication speed (DS) and communication speed (DR) among the elements included in the communication parameter CPI is the TA(1) (interface byte) in the ATS shown in Figure 4. Set in DS (bits b7 to b5) and DR (bits b3 to b1) in In addition, when starting communication from the IDLE state, information indicating the maximum waiting time (FWT) and start frame guard time (SFGT) among the elements included in the communication parameter CPI is TB(1) in the ATS shown in FIG. Set in FWI (bits b8-b5) and SFGI (bits b4-b1) in (interface byte). In addition, when starting communication from the IDLE state, information indicating the standby state type (IDLE state) among the elements included in the communication parameter CPI is stored in any of T1 to Tk (historical bytes) in the ATS shown in Figure 4. bit is set.

On the other hand, for example, when IC chip 1 starts communication from the HALT state, information indicating the maximum frame size (FSC) (for example, "1111") among the elements included in the communication parameter CPH is Set in FSCI (bits b4-b1) in T0. In addition, when starting communication from the HALT state, information indicating the communication speed (DS) and communication speed (DR) among the elements included in the communication parameter CPH is changed to DS ( bits b7-b5) and DR (bits b3-b1). In addition, when starting communication from the HALT state, information indicating the maximum waiting time (FWT) and start frame guard time (SFGT) among the elements included in the communication parameter CPH is TB(1) in the ATS shown in Figure 4. FWI (bits b8 to b5) and SFGI (bits b4 to b1) in Furthermore, when starting communication from the HALT state, information indicating the standby state type (HALT state) among the elements included in the communication parameter CPH is set to any bit in T1 to Tk in the ATS shown in FIG. Ru.

FIG. 5 is a diagram illustrating an example of an ATQB encoding configuration (extended format defined by ISO/IEC14443-3). For example, when the IC chip 1 starts communication from the IDLE state, information indicating the communication speed capability (BRC) (for example, "00000010") among the elements included in the communication parameter CPI is the protocol information in ATQB shown in FIG. This is set in the BRC (bits b8 to b1) in the 10th byte. In addition, when starting communication from the IDLE state, information indicating the maximum frame size (FSC) among the elements included in the communication parameter CPI is stored in the FSCI (bit b8 ~b5). In addition, when starting communication from the IDLE state, information indicating the maximum waiting time (FWT) among the elements included in the communication parameter CPI is stored in the FWI (bit b8 ~b5). In addition, when starting communication from the IDLE state, information indicating the guard time (SFGT) of the start frame among the elements included in the communication parameter CPI is included in the SFGI ( bits b8 to b5).

On the other hand, for example, when the IC chip 1 starts communication from the HALT state, information indicating the communication speed capability (BRC) (for example, "00000100") among the elements included in the communication parameter CPH is Set in BRC (bits b8 to b1) in the 10th byte in the protocol information. In addition, when starting communication from the HALT state, information indicating the maximum frame size (FSC) among the elements included in the communication parameter CPH is stored in the FSCI (bit b8 ~b5). In addition, when starting communication from the HALT state, information indicating the maximum waiting time (FWT) among the elements included in the communication parameter CPH is set to FWI (bit b8 ~b5). In addition, when starting communication from the HALT state, information indicating the guard time (SFGT) of the start frame among the elements included in the communication parameter CPH is included in the SFGI ( bits b8 to b5).

As described above, the CPU 15 of the IC chip 1 transmits information indicating the communication parameter CPI to the external device 2 by a response signal when starting communication from the IDLE state, and transmits the communication parameter CPI when starting communication from the HALT state. Information indicating the CPH is transmitted to the external device 2 by a response signal. Here, with reference to FIGS. 6 and 7, a case where communication is started from the IDLE state and a case where communication is started from the HALT state will be described in relation to the state transition of the IC chip 1. FIG. 6 is a diagram showing the state transition of the IC chip 1 that employs Type A as the communication method. FIG. 7 is a diagram showing the state transition of the IC chip 1 that employs Type B as the communication method. Note that the specific conditions for the state transition of the IC chip 1 are well known in ISO/IEC14443-3, so the explanation will be omitted.

First, in Type A, as shown in FIG. 6, the IC chip 1 is in the POWER-OFF state and no power is supplied when it is outside the operating magnetic field radiated by the external device 2, but when it enters the operating magnetic field. When this happens, power is supplied and the device transitions to IDLE state. In the IDLE state, if the IC chip 1 successfully receives REQA (Request Command Type A) or WUPA (Wake UP command Type A) from the external device 2 (that is, when starting communication from the IDLE state), the IC chip 1 performs the above-mentioned Among the elements included in the communication parameter CPI, ATQA including information indicating the size of the UID of the IC chip 1 is transmitted to the external device 2, and the state is changed to READY. In the READY state, the IC chip 1 transitions to the ACTIVE state when the UID of the IC chip 1 is selected by the external device 2. In the ACTIVE state, when the IC chip 1 receives a RATS (Request for Answer To Select) from the external device 2 (this case also applies when communication starts from the IDLE state through the ACTIVE state), the IC chip 1 performs the same operation as described above. Then, it transmits ATS including information indicating the maximum frame size (FSC), communication speed (DS), communication speed (DR), etc. among the elements included in the communication parameter CPI to the external device 2, and transitions to the PROTOCOL state.

On the other hand, in the ACTIVE state, when the IC chip 1 normally receives an HLTA (HaLT command, Type A) from the external device 2, it transitions to the HALT state. This HALT state is a state in which only WUPA can be received. In the HALT state, when the IC chip 1 normally receives WUPA from the external device 2 (that is, when starting communication from the HALT state), the IC chip 1 out of the elements included in the communication parameter CPH, as described above, Sends ATQA including information indicating the size of the UID to external device 2, and transitions to READY ^* state. In the READY ^* state, when the UID of the IC chip 1 is selected by the external device 2, the IC chip 1 transitions to the ACTIVE ^* state. In the ACTIVE ^* state, when the IC chip 1 receives RATS from the external device 2 (this also applies to the case where communication is started from the HALT state through the ACTIVE ^* state), the communication parameter CPH is set as described above. The ATS including information indicating the maximum frame size (FSC), communication speed (DS), communication speed (DR), etc. among the elements included in is transmitted to the external device 2, and transitions to the PROTOCOL state.

Next, in Type B, as shown in FIG. 7, when the IC chip 1 enters the operating magnetic field, as in Type A, power is supplied and the IC chip 1 transitions to the IDLE state. In the IDLE state, when the IC chip 1 normally receives REQB (Request Command Type B) or WUPB from the external device 2 (that is, when starting communication from the IDLE state), the IC chip 1 changes the communication parameter CPI to The ATQB, which includes information indicating communication speed capability (BRC), maximum frame size (FSC), etc. among the included elements, is transmitted to the external device 2, and transitions to the READY-REQUESTED state or READY-DECLARED state. In the READY-DECLARED state, when the IC chip 1 normally receives ATTRIB (PICC selection command, Type B) from the external device 2, it transitions to the PROTOCOL state. On the other hand, in the READY-DECLARED state, when the IC chip 1 normally receives an HLTB (HaLT command, Type B) from the external device 2, it transitions to the HALT state. This HALT state is a state in which only WUPB can be received. In the HALT state, when the IC chip 1 normally receives WUPB from the external device 2 (that is, when starting communication from the HALT state), the IC chip 1 determines the communication speed capability among the elements included in the communication parameter CPH, as described above. (BRC) and maximum frame size (FSC), etc., to the external device 2, and transitions to the READY-REQUESTED state or READY-DECLARED state.

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[2. Operation of IC chip 1]
Next, the operation of the IC chip 1 will be explained with reference to FIG. FIG. 8 is a flowchart showing an example of communication parameter transmission processing executed by the CPU 15 of the IC chip 1. The process shown in FIG. 8 is started when a command (REQA, WUPA, REQB, or WUPB) is received from the external device 2 while the IC chip 1 is in the IDLE state or HALT state. When the process shown in FIG. 8 is started, the CPU 15 determines whether the current state of the IC chip 1 is the IDLE state or the HALT state (step S1). If it is determined that the current state of the IC chip 1 is the IDLE state (step S1: IDLE state), the process advances to step S2. On the other hand, if it is determined that the current state of the IC chip 1 is the HALT state (step S1: HALT state), the process proceeds to step S6.

In step S2, the CPU 15 searches for the communication parameter CPI corresponding to the IDLE state. For example, the presence or absence of a file that manages information indicating the communication parameter CPI is searched. Next, the CPU 15 determines whether the communication parameter CPI corresponding to the IDLE state is set (that is, stored in the NVM 13) based on the search result in step S2 (step S3). If it is determined that the communication parameter CPI corresponding to the IDLE state is set (step S3: YES), for example, if a file managing information indicating the communication parameter CPI is found, the process proceeds to step S4. On the other hand, if it is determined that the communication parameter CPI corresponding to the IDLE state is not set (step S3: NO), the process proceeds to step S5.

In step S4, the CPU 15 reads information indicating the communication parameter CPI from the NVM 13, sets it in the above-mentioned response signal (adjusts the data format as necessary), and advances the process to step S9. On the other hand, in step S5, the CPU 15 reads information indicating the default communication parameter CPD from the NVM 13, sets it in the above-mentioned response signal, and advances the process to step S9.

On the other hand, in step S6, the CPU 15 searches for a communication parameter CPH corresponding to the HALT state. For example, the presence or absence of a file that manages information indicating the communication parameter CPH is searched. Next, the CPU 15 determines whether the communication parameter CPH corresponding to the HALT state is set (that is, stored in the NVM 13) based on the search result in step S6 (step S7). If it is determined that the communication parameter CPH corresponding to the HALT state is set (step S7: YES), for example, if a file managing information indicating the communication parameter CPH is found, the process proceeds to step S8. On the other hand, if it is determined that the communication parameter CPH corresponding to the HALT state is not set (step S7: NO), the process moves to step S5.

In step S8, the CPU 15 reads information indicating the communication parameter CPH from the NVM 13, sets it in the above-mentioned response signal (adjusts the data format as necessary), and advances the process to step S9. In step S9, the CPU 15 transmits the response signal in which the information indicating the communication parameters was set in step S4, S5, or S8 to the external device 2 via the I/O circuit 11 and the antenna, and ends the process. The process shown in FIG. 8 described above can be universally applied to the existing IC chip 1 in order to implement the present invention.

As explained above, according to the above embodiment, the IC chip 1 transmits information indicating the communication parameter CPI to the external device 2 by a response signal when starting communication from the IDLE state, while starting communication from the HALT state. Since the configuration is configured so that information indicating the communication parameter CPH is sent to the external device 2 by a response signal when starting the communication, two types of communication parameters corresponding to the two types of standby states, IDLE state and HALT state, are sent to the external device 2. can be presented to. Therefore, the external device 2 can communicate with the IC chip 1 by switching the communication parameter that is more suitable for the external device 2 out of the two types of communication parameters presented at different timings. Performance can be improved. Further, according to the above embodiment, when starting communication from the IDLE state, the IC chip 1 includes information indicating the IDLE state in the information indicating the communication parameter CPI and transmits it to the external device 2. Since the configuration is such that when starting communication, the information indicating the HALT state is included in the information indicating the communication parameter CPH and transmitted to the external device 2, the external device 2 immediately connects the IC chip 1 upon receiving the response signal from the IC chip 1. Since the current state of the chip 1 can be recognized, communication parameters can be switched more quickly.

In the above embodiment, the case where the IC chip 1 and the external device 2 perform contactless communication has been described, but the present invention is also applicable to the case where the IC chip 1 and the external device 2 perform contact communication. be. In this case, the IC chip 1 is in a first contact communication state when starting contact communication from a reception standby state (an example of a first standby state) of a cold reset (that is, a reset executed immediately after the IC chip 1 is activated). Information indicating communication parameters and a second communication when contact communication is started from a reception standby state (an example of a second standby state) of a warm reset (that is, a reset performed when the voltage and clock are in a stable state). and information indicating the parameters. When the IC chip 1 receives the cold reset and starts contact communication from the cold reset reception standby state, it transmits information indicating the first communication parameter to the external device 2, while the warm reset reception standby state When receiving the warm reset from , and starting contact communication, information indicating the second communication parameters is transmitted to the external device 2 .

1 IC chip 11 I/O circuit 11a Power supply circuit 11b Clock generation circuit 11c Modulation/demodulation circuit 12 RAM
13 NVM
14 ROM
15 CPU

Claims (11)

An electronic information storage medium capable of communicating with an external device,
information indicating a first communication parameter when starting the communication from a first standby state in which communication with the external device is waited; and a second standby state in which communication with the external device is waited. storage means for storing information indicating a second communication parameter when starting the communication from a second standby state different from the first standby state;
When starting the communication from the first standby state, information indicating the first communication parameter is transmitted to the external device, and when starting the communication from the second standby state, the second communication parameter is indicated. transmitting means for transmitting information to the external device;
An electronic information storage medium comprising: 2. The electronic information storage medium according to claim 1, wherein the information indicating the communication parameters includes information indicating at least one of a maximum frame size, a maximum waiting time, and a communication speed. 2. The information indicating the first communication parameter includes information indicating the first standby state, and the information indicating the second communication parameter includes information indicating the second standby state. Electronic information storage medium as described. The electronic information according to any one of claims 1 to 3, wherein the communication is contactless communication, the first standby state is an IDLE state, and the second standby state is a HALT state. storage medium. An IC chip capable of communicating with an external device,
information indicating a first communication parameter when starting the communication from a first standby state in which communication with the external device is waited; and a second standby state in which communication with the external device is waited. storage means for storing information indicating a second communication parameter when starting the communication from a second standby state different from the first standby state;
When starting the communication from the first standby state, information indicating the first communication parameter is transmitted to the external device, and when starting the communication from the second standby state, the second communication parameter is indicated. a transmitting means for transmitting information to the external device;
An IC chip characterized by comprising: An IC card capable of communicating with an external device,
information indicating a first communication parameter when starting the communication from a first standby state in which communication with the external device is waited; and a second standby state in which communication with the external device is waited. storage means for storing information indicating a second communication parameter when starting the communication from a second standby state different from the first standby state;
When starting the communication from the first standby state, information indicating the first communication parameter is transmitted to the external device, and when starting the communication from the second standby state, the second communication parameter is indicated. a transmitting means for transmitting information to the external device;
An IC card characterized by comprising: A communication parameter transmission method performed by an electronic information storage medium capable of communicating with an external device, the method comprising:
information indicating a first communication parameter when starting the communication from a first standby state in which communication with the external device is waited; and a second standby state in which communication with the external device is waited. and storing information indicating a second communication parameter when starting the communication from a second standby state different from the first standby state;
When starting the communication from the first standby state, information indicating the first communication parameter is transmitted to the external device, and when starting the communication from the second standby state, the second communication parameter is indicated. transmitting information to the external device;
A communication parameter transmission method characterized by comprising: A computer included in an electronic information storage medium that can communicate with an external device,
information indicating a first communication parameter when starting the communication from a first standby state in which communication with the external device is waited; and a second standby state in which communication with the external device is waited. and storing information indicating a second communication parameter when starting the communication from a second standby state different from the first standby state;
When starting the communication from the first standby state, information indicating the first communication parameter is transmitted to the external device, and when starting the communication from the second standby state, the second communication parameter is indicated. transmitting information to the external device;
A program characterized by executing. An electronic information storage medium capable of communicating with an external device, the electronic information storage medium comprising a memory that stores at least information indicating default communication parameters used in communication with the external device,
The current state of the electronic information storage medium is a first standby state in which it waits for communication with the external device, or a second standby state in which it waits for communication with the external device. a first determining means for determining whether the second standby state is different from the first standby state;
If it is determined that the current state is the first standby state, it is determined whether information indicating a first communication parameter when starting the communication from the first standby state is stored in the memory. On the other hand, when it is determined that the current state is the second standby state, whether information indicating a second communication parameter for starting the communication from the second standby state is stored in the memory. a second determination means for determining whether
If it is determined that the information indicating the first communication parameter is not stored in the memory, the information indicating the default communication parameter is transmitted to the external device, and the information indicating the first communication parameter is not stored in the memory. a first transmitting means for transmitting information indicating the first communication parameter to the external device if it is determined that the first communication parameter is stored in the external device;
If it is determined that the information indicating the second communication parameter is not stored in the memory, the information indicating the default communication parameter is transmitted to the external device, while the information indicating the second communication parameter is not stored in the memory. a second transmitting means for transmitting information indicating the second communication parameter to the external device when it is determined that the second communication parameter is stored in the external device;
An electronic information storage medium comprising: An electronic information storage medium capable of communicating with an external device, the electronic information storage medium comprising a memory that stores at least information indicating default communication parameters used in communication with the external device. A method for transmitting communication parameters, the method comprising:
The current state of the electronic information storage medium is a first standby state in which it waits for communication with the external device, or a second standby state in which it waits for communication with the external device. determining whether the second standby state is different from the first standby state;
If it is determined that the current state is the first standby state, it is determined whether information indicating a first communication parameter when starting the communication from the first standby state is stored in the memory. On the other hand, when it is determined that the current state is the second standby state, whether information indicating a second communication parameter for starting the communication from the second standby state is stored in the memory. a step of determining whether
If it is determined that the information indicating the first communication parameter is not stored in the memory, the information indicating the default communication parameter is transmitted to the external device, and the information indicating the first communication parameter is not stored in the memory. If it is determined that the first communication parameter is stored in the first communication parameter, transmitting information indicating the first communication parameter to the external device;
If it is determined that the information indicating the second communication parameter is not stored in the memory, the information indicating the default communication parameter is transmitted to the external device, while the information indicating the second communication parameter is not stored in the memory. If it is determined that the second communication parameter is stored in the second communication parameter, transmitting information indicating the second communication parameter to the external device;
A communication parameter transmission method characterized by comprising: A computer included in an electronic information storage medium that is capable of communicating with an external device and that includes a memory that stores at least information indicating default communication parameters used in communication with the external device. To,
The current state of the electronic information storage medium is a first standby state in which it waits for communication with the external device, or a second standby state in which it waits for communication with the external device. determining whether the second standby state is different from the first standby state;
If it is determined that the current state is the first standby state, it is determined whether information indicating a first communication parameter when starting the communication from the first standby state is stored in the memory. On the other hand, when it is determined that the current state is the second standby state, whether information indicating a second communication parameter for starting the communication from the second standby state is stored in the memory. a step of determining whether
If it is determined that the information indicating the first communication parameter is not stored in the memory, the information indicating the default communication parameter is transmitted to the external device, and the information indicating the first communication parameter is not stored in the memory. If it is determined that the first communication parameter is stored in the first communication parameter, transmitting information indicating the first communication parameter to the external device;
If it is determined that the information indicating the second communication parameter is not stored in the memory, the information indicating the default communication parameter is transmitted to the external device, while the information indicating the second communication parameter is not stored in the memory. If it is determined that the second communication parameter is stored in the second communication parameter, transmitting information indicating the second communication parameter to the external device;
A program characterized by executing.

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