METHOD FOR DETECTING THAT CONTACTLESS CPU CARD LEAVES RADIO-FREQUENCY FIELD

• US 20150091699A1
• Filed: 12/21/2012
• Published: 04/02/2015
• Est. Priority Date: 05/30/2012
• Status: Active Grant

• Current Assignee: Feitian Technologies Company Limited
• Original Assignee: Feitian Technologies Company Limited
• Inventors: Lu, Zhou, Yu, Huazhang
• Granted Patent: US 9,754,142 B2
• Time in Patent Office: Days
• US Class Current: 340/10.1
• CPC Class Codes: G06K 7/10128 the step consisting of detection of the presence of one or more record carriers in the vicinity of the interrogation device
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications

Abstract

A method for detecting that a contactless CPU card leaves a radio-frequency field relates to the field of smart cards. The method comprises: receiving and judging whether a valid instruction sent by an upper computer is received, and conducting a corresponding operation according to the received instruction; as a notification card search instruction, conducting a card search operation, and judging whether returned information is received; obtaining card number information about a contactless card according to the returned information; as an APDU instruction, sending A data to the card in accordance with a designated format, judging whether a response is received, and sending the operation result to the upper computer; as an extension instruction, executing a corresponding operation, and sending the operation result to the upper computer; when a valid instruction is not received, judging the mark of the card in the radio-frequency field, and if the card is in the radio-frequency field, conducting a card detection operation, and sending the operation result to the upper computer; and if the card is not in the radio-frequency field, conducting a card search operation. The present invention can detect the problem that a CPU card leaves a radio-frequency field in real time.

Claims

1. A method for detecting whether a contactless CPU card has left a radio frequency field, comprising

Step A, a card reader obtaining an instruction and determining whether the instruction is a valid instruction, if yes, go to Step B;

otherwise, go to step C;

Step B, the card reader determining the type of the valid instruction;

if the type is an instruction on informing to seek a card, go to Step D;

if the type is an APDU instruction, sending the APDU instruction to the card, and sending a response returned by the card to a master computer via USB interrupting channel;

then go back to Step A;

if the type is an extension instruction, performing operation according to the extension instruction, and sending a result of the operation to the master computer via USB interrupting channel;

then go back to Step A;

Step C, the card reader determining whether a flag of the card in the radio frequency field is set, if yes, go to Step E;

otherwise, go to Step D;

Step D, the card reader sends a card seeking instruction to the card and determines whether the card reader receives a card seeking response returned by the card, if yes, setting the flag of the card in the radio frequency field and sending the response that the card is in the radio frequency field to the master computer via USB interrupting channel;

otherwise, resetting the flag of the card in the radio frequency field and sending the response that card leaves the radio frequency field to the master computer via USB interrupting channel;

then go back to Step A;

Step E, the card reader sending a detecting instruction to the card and determining whether the card reader receives a detecting response returned by the card successfully, if yes, storing the detecting response and go to Step F;

otherwise, go to Step G;

Step F, the card reader setting the flag of the card in the radio frequency field, and sending the response that the card is in the radio frequency field to the master computer via USB interrupting channel;

go back to Step A; and

Step G, the card reader resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel;

then go back to Step A.

2. The method of claim 1, wherein sending response that the card is in the radio frequency field to the master computer via USB interrupting channel specifically comprises

determining whether a recorded card status is that the card is in the radio frequency field, if yes, go back to Step A;

otherwise, updating the recorded card status to be that card is in the radio frequency field and go back to Step A; and

informing the master computer of the response that card leaves the radio frequency field via USB interrupting channel specifically comprises

determining whether the recorded card status is that the card leaves the radio frequency, if yes, go back to Step A;

otherwise, updating the recorded card status to be that card leaves the radio frequency field, then go back to Step A.

3. The method of claim 1, wherein determining whether the instruction is a valid instruction specifically comprises

the card reader receiving instruction sent from buffer via an interrupting way;

if the first byte of the instruction is identical to a predetermined character, the card reader receiving the valid instruction;

otherwise, the card reader receiving no valid instruction.

4. The method of claim 1, wherein before Step A, the method comprises

the card reader is powered up and initialized, switching on communication interruption enabling;

the method further comprises when the card reader detects communication interrupting, the card reader entering communication interrupting process, which comprises

StepS1, the card reader switches off communication interruption enabling, clearing a communication interrupting flag;

StepS2, the card reader receives an instruction issued from the master computer and determines whether the instruction is a valid instruction, if yes, setting the flag of the instruction, switching on communication interruption enabling and exiting the communication interrupting process;

otherwise, switching on communication interruption enabling and exiting the communicating interrupting process;

Step A specifically comprises the card reader determining whether the flag of the instruction is set, if yes, resetting the flag of the instruction and go to Step B;

if no, go to Step C.

5. The method of claim 4, wherein determining whether the instruction is a valid instruction in Step S2 specifically comprises

determining whether the first byte of the instruction is identical to a predetermined character, if yes, the valid instruction is received, if no, the valid instruction is not received.

6. The method of claim 1, wherein the card reader sending the detecting instruction to the card in Step E specifically comprises

if it is the first time that the card reader sends the detecting instruction, the card reader sends a first predetermined character string to the card;

while

if it is not the first time that the card reader sends the detecting instruction, the card reader determines the detecting instruction to be sent according to the detecting response, if the value of the last bit of the detecting response is 0, the card reader sends a first predetermined character string to the card;

if the value of the last bit of the detecting response is 1, the card reader sends a second predetermined character string to the card.

7. The method of claim 6, wherein determining whether the card successfully receives the detecting response returned by the card in Step E specifically comprises

if the detecting instruction is the first predetermined character, the card reader determines whether the received response returned by the card is a first detecting response, if yes, receiving the detecting response returned by the card successfully and storing the response;

if no, receiving the detecting response returned by the card unsuccessfully;

while

if the detecting instruction is the second predetermined character, the card reader determines whether the received response returned by the card is a second detecting response, if yes, receiving the detecting response returned by the card successfully and storing the response;

if no, receiving the detecting response returned by the card unsuccessfully.

8. The method of claim 7, wherein Step B specifically comprises

Step B11, the card reader determining type of the valid instruction, if the type is the instruction on informing to seek a card, going to Step D;

while if the type is the APDU instruction, go to Step B12;

if the type is the extension instruction, go to Step B13;

Step B12, the card reader sending the APDU instruction to the card and determining whether the card reader receives a response returned by the card;

if yes, setting the flag of the card in the radio frequency field and returning the received response to the master computer via USB interrupting channel, go back to Step A;

otherwise, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, then go back to Step A; and

Step B13, the card reader performing operation according to the extension instruction and returning the result of operation to the master computer via USB interrupting channel, then go back to Step A.

9. The method of claim 8, wherein Step D specifically comprises

Step D11, the card reader sending a first requesting instruction to the card and determining whether receives a first response returned by the card, if yes, go to Step D12;

otherwise, closing the radio frequency field;

waiting for automatically opening the radio frequency field in a predetermined time, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, go back to Step A;

Step D12, the card reader sending a second requesting instruction containing 0x93 and 0x20 to the card and obtaining a first confirming information to the card;

Step D13, the card reader obtaining a first data according to the first confirming information and a fixed data and determining whether the first data is 0x00, if yes, a cascade level of the card is 1 and the card number information is stored in buffer;

go to Step D18;

otherwise, go to Step D14;

Step D14, the card reader sending a third requesting instruction containing 0x95 and 0x20 to the card and obtaining a second confirming information returned by the card;

Step D15, the card reader obtaining a second data according to the second confirming information and the fixed data and determining whether the second data is 0x00, if yes, the cascade level of the card is 2 and the card number information is stored in the buffer, go to Step D18;

otherwise, go to Step D16;

Step D16, the card reader sending a fourth requesting instruction containing 0x97 and 0x20 to the card and obtaining a third confirming information;

Step D17, the card reader obtaining a third data according to the third confirming information and the fixed data and determining whether the third data is 0x00, if yes, the cascade level of the card is 3 and the card number information is stored in the buffer and go to D18;

otherwise, closing the radio frequency field;

waiting for automatically opening the radio frequency field in a predetermined time, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel;

go back to Step A;

Step D18, the card reader sending a request selecting and answering instruction to the card and determining whether the card reader receives a selecting and answering response returned by the card, if yes, going to Step D19;

otherwise, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel;

then go back to Step A; and

Step D19, the card reader setting the flag of the card in the radio frequency field and sending the selecting and answering response and the response that the card is in the radio frequency field to the master computer via USB interrupting channel;

then go back to Step A.

10. The method of claim 8, wherein Step D specifically comprises

Step D21, the card reader sending a fifth requesting instruction to the card and determining whether the card reader receives a fifth response returned by the card, if yes, goes to Step D22;

otherwise, closing the radio frequency field, waiting for automatically opening the radio frequency field in a predetermine time, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, then go back to Step A;

Step D22, the card reader sending the request selecting and answering instruction and determining whether the card reader receives the selecting and answering response returned by the card, if yes, go to Step D23;

otherwise, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master compute via USB interrupting channel;

then go back to Step A;

Step D23, the card reader setting the flag of the card in the radio frequency field and sending the selecting and answering response and the response that the card is in the radio frequency field to the master computer via USB interrupting channel;

then go back to Step A.

11. A method for detecting whether a contactless CPU card has left a radio frequency field, comprising

Step a, a card reader switching on regular interruption enabling;

Step b, the card reader receiving an instruction sent by the master computer and determining whether the card reader receives a valid instruction, if yes, determining the type of the valid instruction, if the type is an instruction on informing to seek a card, go to Step c;

if the type is an APDU instruction, go to Step d;

if the type is an extension instruction, go to Step e;

otherwise, go to Step f;

Step c, the card reader switching off the regular interruption enabling, sending a card seeking instruction to the card and determining whether the card reader receives a card seeking response returned by the card, if yes, setting the flag of the card in the radio frequency field and switching on regular interruption enabling, goes to Step f;

otherwise, resetting the flag of the card in the radio frequency field and switching on regular interruption enabling, go to Step f;

Step d, the card reader switching off regular interruption enabling, sending the APDU instruction to the card and determining whether the card reader receives a response returned by the card, if yes, setting the flag of the card in the radio frequency field, sending the received response to the master computer via USB interrupting channel and switching on regular interruption enabling, then go to Step f;

otherwise, resetting the flag of the card in the radio frequency field and switching on regular interruption enabling, go to Step f;

Step e, the card reader switching off regular interruption enabling, performing operation according to the extension instruction, sending the operation result to the master computer via USB interrupting channel and switching on regular interruption enabling, go to Step f;

Step f, the card reader determining whether the flag of the card in the radio frequency field is set, if yes, sending the response that the card is in the radio frequency field to the master computer via USB interrupting channel, then go back to Step a;

otherwise, sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, then go back to Step a;

when the card reader receives triggering of regular interrupting, entering regular interrupting process, comprising

Step g, the card reader switching off regular interruption enabling and clearing any regular interrupting flag

Step h, the card reader determining whether the flag of the card in the radio frequency field is set, if yes, goes to Step i;

otherwise, sending card seeking instruction to the card and determining whether receiving a card seeking response returned by the card, if yes, go to Step l;

otherwise, go to Step m;

Step i, the card reader sending detecting instruction to the card and determining whether the card reader receives a detecting response returned by the card, if yes, storing the detecting response and go to Step l;

otherwise, go to Step m;

Step l, the card reader switching on regular interruption enabling, exiting the regular interrupting process; and

Step m, the card reader resetting the flag of the card in the radio frequency field, switching on regular interruption enabling, and exiting the regular interrupting process.

12. The method of claim 11, wherein Step c specifically comprises

Step c11, the card reader switching off regular interruption enabling, sending a first requesting instruction to the card, determining whether the card reader receives a first response returned by the card, if yes, go to Step c12;

otherwise, closing the radio frequency field, waiting for automatically opening the radio frequency filed in a predetermined time, resetting the flag of the card in the radio frequency field and switching on regular interruption enabling, then go to Step f;

Step c12, the card reader sending a second requesting instruction containing 0x9 3 and 0x20 to the card and obtaining a first confirming information returned by the card;

Step c13, the card reader obtaining a first data according to a first confirming information and a fixed data and determining whether a first data is 0x00, if yes, the cascade level of the card is 1, the card number information is stored in buffer, then go to Step c18;

otherwise, go to Step c14;

Step c14, the card reader sending a third requesting instruction containing 0x95 and 0x20 to the card and obtaining a second confirming information returned by the card;

Step c15, the card reader obtaining a second data according to the second confirming information and the fixed data and determining whether the second data is 0x00, if yes, the cascade level of the card is 2 and the card number information is stored in the buffer, then go to Step c18;

otherwise, go to Step c16;

Step c16, the card reader sending a fourth requesting instruction containing 0x97 and 0x20 to the card and obtaining a third confirming information;

Step c17, the card reader obtaining a third data according to the third confirming information and the fixed data and determining whether the third data is 0x00, if yes, the cascade level of the card is 3 and the card number information is stored in the buffer, go to Step c18;

otherwise, closing the radio frequency field, waiting for automatically opening the radio frequency field in a predetermined time, resetting the flag of the card in the radio frequency field and switching on regular interruption enabling, go to Step f;

Step c18, the card reader sending a request selecting and answering instruction to the card and determining whether the card reader receives a selecting and answering response returned by the card, if yes, go to Step c19;

otherwise, resetting the flag of the card in the radio frequency field and switching on regular interruption enabling;

then go to Step f; and

Step c19, the card reader setting the flag of the card in the radio frequency field and sending the selecting and answering response to the master computer via USB interrupting channel and switching on regular interruption enabling, then go to Step f.

13. The method of claim 11, wherein Step c specifically comprises

Step c21, the card reader switching off regular interruption enabling, sending a fifth requesting instruction to the card and determining whether the card reader receives a fifth response returned by the card, if yes, go to Step c22, otherwise, closing radio frequency field and waiting for automatically opening the radio frequency field, resetting the flag of the card in the radio frequency field and switching on regular interruption enabling;

then go to Step f;

Step c22, the card reader sending a request selecting and answering instruction to the card and determining whether the card reader receives a selecting and answering response returned by the card, if yes, go to Step c23;

otherwise, resetting the flag of the card in the radio frequency field and switching on regular interruption enabling;

then go to Step f; and

Step c23, the card reader setting the flag of the card in the radio frequency field, sending the selecting and answering response to the master computer and switching on regular interruption enabling, then go to Step f.

14. The method of claim 11, wherein if no valid instruction is received in Step b, going on waiting for receiving instruction;

Steps c to f, Steps l to m are replaced with Steps c′

to e′ and

Steps l′

to m′

, respectively;

Step c′

, the card reader switching off regular interruption enabling and sending a card seeking instruction to the card and determining whether a card seeking response is returned by the card, if yes, setting the flag of the card in the radio frequency field and sending the response that the card is in the radio frequency field to the master computer via USB interrupting channel;

then go back to Step a;

otherwise, resetting the flag of the card in the radio frequency field and sending a response that the card leaves the radio frequency field to the master computer via USB interrupting channel, then go back to Step a;

Step d′

, the card reader switching off regular interruption enabling, sending the APDU instruction to the card and determining whether the card reader receives a response returned by the card, if yes, setting the flag of the card in the radio frequency field and sending the received response and the response that the card is in the radio frequency field to the master computer via USB interrupting channel, go back to Step a;

otherwise, resetting the flag of the card in the radio frequency field and sending the response that the card is in the radio frequency field to the master computer via USB interrupting channel, go back to Step a;

Step e′

, the card reader switching off regular interruption enabling, performing operation according to the extension instruction and sending the operation result to the master computer via USB interrupting channel, then go back to Step a;

Step l′

, the card reader setting the flag of the card in the radio frequency field, sending the response that the card is in the radio frequency field to the master computer via USB interrupting channel, switching on regular interruption enabling and exiting regular interrupting process; and

Step m′

, the card reader resetting the flag of the card in the radio frequency field, sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, switching on regular interruption enabling and exiting regular interrupting process.

15. The method of claim 14, wherein Step c′

specifically comprises

Step c′

11, the card reader switching off regular interruption enabling, sending a first requesting instruction to the card and determining whether the card reader receives a first response returned by the card, if yes, go to Step c′

12;

otherwise, closing radio frequency field, waiting for automatically opening the radio frequency field in a predetermined time, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, go back to Step a;

Step c′

12, the card reader sending a second requesting instruction containing 0x93 and 0x20 to the card and obtaining a first confirming information returned from the card;

Step c′

13, the card reader obtaining a first data according to the first confirming information and the fixed data and determining whether the first data is 0x00, if yes, the cascade level of the card is 1 and storing the card number information is stored in buffer, then go to Step C′

18;

otherwise, go to Step c′

14;

Step c′

14, the card reader sending a third requesting instruction containing 0x95 and 0x20 to the card and obtaining a second confirming information returned by the card;

Step c′

15, the card reader obtaining a second data according to the second confirming information and the fixed data and determining whether the second data is 0x00, if yes, the cascade level of the card is 2 and the card number information is stored in the buffer, then go to Step c′

18;

otherwise, go to Step c′

16;

Step c′

16, the card reader sending a fourth requesting instruction containing 0x97 and 0x20 to the card and obtaining a third confirming information;

Step c′

17, the card reader obtaining a third data according to the third confirming information and the fixed data and determining whether the third data is 0x00, if yes, the cascade level of the card is 3 and the card number information is stored in buffer, then go to Step c′

18;

otherwise, closing the radio frequency field, waiting for automatically opening the radio frequency field in a predetermined time, restoring the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, then go back to Step a;

Step c′

18, the card reader sending a request selecting and answering instruction to the card and determining whether the card reader receives a selecting and answering response returned by the card, if yes, go to Step c′

19;

otherwise, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, then go back to Step a; and

Step c′

19, the card reader setting the flag of the card in the radio frequency field and sending the selecting and answering response and the response that the card is in the radio frequency field to the master computer via USB interrupting channel;

then go back to Step a.

16. The method of claim 14, wherein Step c′

specifically comprises

Step c′

21, the card reader switching off regular interruption enabling and sending a fifth requesting instruction to the card and determining whether the card reader receives a fifth response returned from the card, if yes, go to Step c′

22;

otherwise, closing radio frequency field, waiting for automatically opening on the radio frequency field in a predetermined time, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel, then go back to Step a; and

Step c′

22, the card reader sends a request selecting and answering instruction to the card and determining whether the card reader receives the selecting and answering response returned by the card, if yes, go to Step c′

23;

otherwise, resetting the flag of the card in the radio frequency field and sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel;

go back to Step a.

17. The method of claim 11, wherein

sending the response that the card is in the radio frequency field to the master computer via USB interrupting channel specifically comprises

determining whether the recorded card status is that the card is in the radio frequency field, if yes, go back to Step a, otherwise, updating the recorded card status to be that the card is in the radio frequency field, go back to Step a;

and

sending the response that the card leaves the radio frequency field to the master computer via USB interrupting channel specifically comprises

determining whether the recorded card status is that the card leaves the radio frequency field, if yes, go back to Step a;

otherwise, updating the recorded card status to be that the card leaves the radio frequency field;

go back to Step a.

18. The method of claim 11, wherein determining whether the instruction is a valid instruction specifically comprises

the card reader receiving an instruction sent from the buffer via interrupting;

if the first byte of the instruction is identical to a predetermined character, the valid instruction is received;

otherwise, no valid instruction is received.

19. The method of claim 11, wherein the card reader sending a detecting instruction to the card specifically comprises

if it is the first time that the card sends the detecting instruction, the card reader sending a first predetermined character to the card;

while

if it is not the first time that the card sends the detecting instruction, the card reader determines the detecting instruction to be sent according to the detecting response, if the value of the last bit of the detecting response is 0, the card reader sends the first predetermined character string to the card;

if the value of the last bit of the detecting response is 1, the card reader sending a second predetermined character string to the card.

20. The method of claim 19, wherein determining whether the card reader successfully receives the detecting response returned by the card specifically comprises

if the detecting instruction is the first predetermined character string, the card reader determines whether the response returned by the card is a first detecting response, if yes, successfully receiving the detecting response returned by the card and storing the response;

if no, unsuccessfully receiving the detecting response returned by the card;

while

if the detecting instruction is the second predetermined character string, the card reader determines whether the response returned by the card is a second detecting response, if yes, successfully receiving the detecting response returned by the card and storing the response;

if no, unsuccessfully receiving the detecting response returned by the card.