JP4056685B2 - Wireless device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention, from the transmitter transmits a predetermined transmission code, for example, lock the locking device, in which relates to wireless equipment which is adapted to perform a responsive action such as unlocking.
[0002]
[Prior art]
As this type of wireless device, for example, there is one as disclosed in Japanese Patent Application Laid-Open No. 8-120987, which will be described below.
A transmission comprising a custom code, a fixed code (ID code), a code (hereinafter referred to as a rolling code), a function code, and an end code as shown in FIG. 6 from a transmitter (not shown) in accordance with the operation of the transmission switch. When the receiver receives the code, the receiver first determines whether or not the received fixed code matches the fixed code of the registered regular code. The rolling code and the normal rolling code (the rolling code of the normal code obtained using a predetermined calculation formula based on the rolling code used in the previous collation) are compared. If the received rolling code matches the normal rolling code, the actuator is driven to perform a predetermined response operation based on the function code.
[0003]
On the other hand, when the authorized owner of the transmitter presses the transmission switch, the rolling code of the transmission code changes, so there is a gap between the normal code and the rolling code. If they do not match, the rolling code used this time is temporarily recorded in the memory of the receiver, and the deviation between the transmission code and the regular code is corrected based on the rolling code of the transmission code input last time. I am doing so. As a result, the transmission code from the transmitter next time matches the regular code.
[0004]
[Problems to be solved by the invention]
In such a device, the ID code is fixed among the transmission codes of the transmitter, and only the rolling code is changed so as to improve the anti-theft performance. Therefore, the occurrence pattern of the rolling code is stolen and the transmission code is read. There is no guarantee that it will not.
[0005]
The present invention has been made paying attention to such problems, and has been made for the purpose of further improving the anti-theft property.
[0009]
[Means for Solving the Problems]
A wireless device according to a first aspect of the present invention includes a transmitter that transmits a different transmission code in accordance with a switch operation, and a receiver that switches a normal code in a predetermined order in response to a change of the transmission code in the transmitter. In a wireless device that performs a predetermined output on the receiver side when the transmission code and the regular code are matched, the receiver has at least an ID code, a rolling code, and a counter value related to a switch operation as the transmission code. wherein the rolling code, ID code, be those that are calculated based on the counter value related to the switch operation, the counter value related to the switching operation from the transmitter, receiving the transmitted code in the receiver When it is determined that the number of times exceeds the specified range, the number of receptions is matched with the number of transmissions. A.
[0010]
According to a second aspect of the present invention, there is provided a wireless device according to the first aspect , wherein the receiver in the first aspect collates the code part after matching the number of receptions with the number of transmissions.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment according to the present invention will be described.
[0012]
Embodiment 1 FIG.
FIG. 1 is a circuit block diagram of the keyless entry device, FIG. 2 is a configuration diagram of a transmission code, and FIG. 3 is a flowchart showing the operation of the CPU 11 shown in FIG.
In FIG. 1, 1 is a portable transmitter (wireless device), 2 is a receiver (wireless device) attached to the automobile side, 3 is an actuator for driving a vehicle door lock / unlock device, It is connected to an interface (I / F) 16. The transmitter 1 is provided with a battery 4, a transmission operation switch (consisting of an unlock switch 5a and a lock switch 5b) 5, a ROM 6, an EEPROM 7, a RAM 8, a CPU 9, and the like, and the receiver 2 A receiver 11, a ROM 12, an EEPROM 13, a RAM 14, a CPU 15, an interface 16 and the like are provided.
[0013]
First, the configuration and operation of the transmitter 1 will be described.
The ROM 6 is a non-volatile memory and has a communication format of a transmission code (consisting of a custom code, an ID code (fixed), a counter value n, a rolling code, a function code, and an end code as shown in FIG. 2). Although stored, the rolling code among the items stored in the ROM 6 includes not only the rolling code itself but also the calculation formula itself for calculating the rolling code. That is, the calculation formula means a counter value n (= a value obtained by combining n1 and n2) in the present invention, which is expressed by an upper bit n1 and a lower bit n2. For example, the upper bit n1 and the lower bit n2 are each 4 bits, and they are expressed as 8 bits.
[0014]
The EEPROM 7 is calculated based on the calculation formula for calculating the rolling code stored in the ROM 6 by the CPU 9 to be described later, and stores the rolling code sent when the operation switch 5 is turned on next time calculated in advance by the CPU 9. To do. Further, the EEPROM 7 stores the number of ON operations in the past of the operation switch 5, that is, the counter value n.
[0015]
When the CPU 9 receives the ON signal from the transmission switch 5, the CPU 9 reads the communication format stored in the ROM 6 and reads the number of ON operations of the switch 5 from the EEPROM 7 until the previous use, that is, the counter value n, A counter value n to be transmitted this time is calculated by adding 1 to the counter value n, and a rolling code to be used at the time of transmission is calculated based on the read calculation formula. The rolling code is calculated based on the calculation formula based on the custom code, ID code, counter value n, function code, and the like.
[0016]
Further, the CPU 9 arranges the calculated rolling code and counter value n and the custom code, ID code, function code and end code read from the ROM 6 into a predetermined communication format and transmits it from the transmission output device 10 as a transmission code. .
[0017]
With the above configuration, the CPU 9 applies the communication format to the counter value n and the rolling code, and transmits the data form as shown in FIG. 2 from the transmission output device 10 to the receiver 2. Thereafter, the counter value n is incremented by 1 and stored in the EEPROM 7.
For example, for the lower bit n1 of the counter value n according to the present invention, as shown in FIG. 4, when the counter value n1 immediately before the ON operation of the first operation switch 5, for example, the unlocking switch 5a, is “00000100”. In the first ON operation, the counter value n1 is “00000101”, the second is “00000110”,..., The thirteenth is “00010001”, and the fourteenth is “00010010”.
[0018]
Next, the receiver 2 will be described.
That is, 11 is a receiver. When a transmission code transmitted from the transmission output unit 10 of the transmitter 1 is received, the CPU 15 selects an ID code from the transmission codes based on a communication format stored in a ROM 12 described later. , Counter value n, rolling code, and function code are extracted.
[0019]
A ROM 12 corresponds to the ROM 6 and stores the transmission format as a reception format. An EEPROM 13 stores a registered normal code, that is, an ID code, a counter value n, and a function code. These various codes are supplied in response to a read request from. The ROM 12 stores a calculation formula for calculating a rolling code, and supplies these various codes in response to a read request from the CPU 15.
[0020]
An EEPROM 13 stores counter values n and S (equal to n1 at the initial setting) in different storage areas, for example, n in area 1 and S in area 2, and counter value n in response to a read request from the CPU 15. , S, the lower bit n1 of the counter value n is supplied.
[0021]
Reference numeral 15 denotes a CPU. When a transmission code including an ID code, a counter value n1, a rolling code and a function code is supplied from the receiver 11, a rolling code calculation formula is read from the ROM 12, and a counter value n is read from the EEPROM 13. , S are read, code verification is performed according to the flowchart shown in FIG. 3, and if the verification result is OK, the actuator 3 is driven via the interface 16 and the code is verified according to the function code. The door lock or unlock is controlled, and if it is NG without verification, it is not controlled. Further, the CPU 15 stores the read counter value n1 in the EEPROM 13.
[0022]
Next, the operation of the CPU 15 will be described below based on the flowchart shown in FIG.
When the transmission code is transmitted from the transmitter 1 to the receiver 11, the CPU 15 extracts the ID code from the communication format of the received transmission code in step ST1, and stores the ID code and the EEPROM 13 in step ST2. The ID code is collated. If the collation in step ST2 is not established and fails as NG, it is determined that an irregularly different transmission code is received, the process proceeds to step ST10, and the collation operation is terminated.
[0023]
In step ST2, if the ID codes match and the collation is OK, the process proceeds to step ST3, where the previously used counter value n1, for example, the counter value n1 shown in FIG. The code having S1 of “00000100” is read from the EEPROM 15, and the process proceeds to step ST4.
[0024]
In step ST4, the upper bit n2 of the counter value n is calculated from the rolling code, ID code, function code received by the receiver 11, and the lower bit n1 of the counter value n.
For the calculation of the upper 8 bits n2 of the counter value n, the received lower bits, for example, the received lower bit for example, a 24-bit ID code are shifted to the left (if the counter value is 24 bits or more, The bit string obtained by shifting the remainder divided by 24), the lower bit n1 of the received counter value n, and the rolling code are arranged to obtain a bit string, and obtained by taking the exclusive bore of them.
[0025]
In step ST5, (the counter value n1 of the counter value n read in step ST3) is subtracted from (the counter value n2 calculated in step ST4) to obtain the difference, and the difference is in the range of 0 to 128. For example, it is considered that it is in the range of erroneous “empty press” of the person who owns the transmitter 1, and proceeds to the next step ST6. If this range is exceeded, transmission codes from other transmitters are transmitted. The process proceeds to step ST11.
[0026]
When the process proceeds to step ST6, the rolling code is calculated from the ID code, the function code, and the custom code based on the counter value n2 calculated in step ST4.
In the next step ST7, if the rolling code read in step ST4 is not matched with the rolling code calculated in step ST6, the process proceeds to step ST10 and the collating operation is prohibited. On the other hand, if the matching is established, the process proceeds to step ST8.
[0027]
In step ST8, the counter values n2 and S2 calculated in step ST4 for the next collation and the counter values n1 and S1 read in step ST2 are combined to create counter values n and S, which are stored in the EEPROM 13. The counter values n and S used last time are rewritten.
Thereafter, the process proceeds to step ST9, and an operation corresponding to the function code read in step ST1 is performed. For example, if the function code indicates door unlock, a signal indicating door lock is sent via the interface 16 to the actuator 3. Then, the process proceeds to step ST10 and the program operation is terminated.
[0028]
If it is determined in step ST5 that the counter value n is a predetermined value, for example, 128 or more, and the process proceeds to step ST11, the counter value S that has been rewritten and stored in step ST8 when the previous transmission code is received is step ST3. The counter value S of the counter values n128, S read in step S is subtracted to obtain the difference. If the difference is in the range of 0 to 128, the person who owns the transmitter 1 is erroneously “empty”. It is considered to be within the range, and the process proceeds to step ST6 and proceeds to normal processing. If this range is exceeded, “empty push” is performed, for example, it is determined that the game has been played, and the process proceeds to steps ST12 and ST13. .
[0029]
In steps ST12 and ST13, the same operations as in steps ST6 and ST7 are performed.
In the next step ST13, if the rolling code read in step ST4 is not matched with the rolling code calculated in step ST12, the process proceeds to step ST10 and the collating operation is prohibited. On the other hand, if the matching is established, the process proceeds to step ST14.
[0030]
In step ST14, as in step ST8, the counter values n2 and S2 calculated in step ST4 for the next collation are combined with the counter values n1 and S1 read in step ST2 to create counter values n and S. And stored in the EEPROM 13.
[0031]
Next, a detailed description of the lower bit portion of the counter value in the above configuration will be given with reference to FIG. The upper bit portion has a large number of digits in a normal switch operation and hardly changes.
(First time)
First, when the counter value n1 of the transmission code of the transmitter 1 is “00000100”, when the unlocking switch 5a is turned on once, the counter value n1 becomes “00000101”, and this counter value n1 is the receiver 2 Since the difference is within 127 in comparison with the counter value n1 ("00000100": S1 is the same) stored in the EEPROM 13, the counter values n1 and S1 are updated to "00000101" in step ST8.
[0032]
(Second time)
Next, when the operation switch 5 is turned on once again, the counter value n1 becomes “00000110”. This counter value n1 is transmitted to the receiver 2 and the counter value n1 (“00000101” previously stored in the EEPROM 13). ": S1 is the same)", the counter values n1 and S1 are updated to "00000110" in step ST8.
[0033]
(On the way)
Here, when the operation switch 5 is pressed 130 times, the counter value n1 of the transmitter 1 is updated to “10000111”.
[0034]
(3rd)
When the unlocking switch 5a is turned on once, the counter value n1 becomes “10001000”. This counter value n1 is transmitted to the receiver 2 and is stored in the EEPROM 13 at the second time (“00000110”: Unlike S1), the difference exceeds the range of 0 to 127. Therefore, only the counter value n1 is updated to “10001000” and the current counter value in step ST14.
[0035]
(4th)
When the unlocking switch 5a is turned on once again, the counter value n1 becomes “10001001”. This counter value n1 is transmitted to the receiver 2 and is stored in the EEPROM 13 at the second time. Since the difference is within 127 in comparison with (“10001000”), the process proceeds from step ST11 to step ST6, which is a step during normal operation, and the counter values n1 and S1 are updated to “10001001”.
[0036]
Next, the calculation method of the counter value n and the calculation method of the rolling code will be described again with reference to FIG.
A transmission code shown in FIG. 5A from the portable transmitter 1 to the receiver 2, that is, a custom code, a function code, an ID code, a rolling code, and a lower bit n1 of the counter value n (K8, K9,... K2, When K1) is transmitted, an ID code is extracted from it, and this ID code (A24, A23,... A2, A1) is shifted to the left by the lower bit n1 of the counter value n received this time. . For example, as shown in FIG. 5B, if the lower order of the counter value n is 27 (when expressed in decimal) and the transmission code is 24 bits, the remainder is 3, so the ID code is shifted three times to the left. A new ID code is obtained (FIG. 5B).
[0037]
Next, an exclusive OR (EXOR) logic is calculated between the new ID code (a24, a23,... A2, a1) and the currently received rolling code (R24, R23,... R2, R1). Then, the upper bits n2 (K16, K15,... K9) of the counter value n are extracted (FIG. 5C).
[0038]
Next, an exclusion OR between the new ID code (a24, a23,..., A2, a1) and the custom code, function code, and counter value n (combined upper bit n2 and lower bit n1) The logic of (EXOR) is calculated to calculate rolling codes (R24, R23,... R2, R1) (FIG. 5D).
Thereafter, the calculated rolling code (R24, R23,... R2, R1) and the received rolling code (R24, R23,... R2, R1) are compared and collated (FIG. 5 (E)). .
[0039]
In the above-described embodiment, the case where the unlocking switch 5a is inserted and operated as the operation switch 5 has been described. However, the case where the locking switch 5b is inserted and pressed may be considered similarly. Further, a trunk opening switch may be added as the operation switch 5, and in this case as well, it may be considered in the same manner as the unlocking switch 5a. Furthermore, when a plurality of switches are simultaneously inserted and operated to generate a new function, this simultaneous insertion may be considered as one switch operation and a function code corresponding to this operation may be generated.
[0040]
【The invention's effect】
As is clear from the above description, according to the present invention, when it is determined that the counter value related to the switch operation from the transmitter exceeds the predetermined range than the reception circuit of the transmission code at the receiver, Match the number of receptions with the number of transmissions, calculate the rolling code based on the ID code and the counter value related to the switch operation, and compare it with the rolling code received from the transmitter. By adopting such a configuration, there is an effect that improvement of the anti-theft property intended for the original purpose can be realized.
[Brief description of the drawings]
FIG. 1 is a circuit block diagram of an embodiment according to the present invention.
FIG. 2 is a transmission code configuration diagram illustrating the configuration of a transmission code used in FIG. 1;
3 is a flowchart showing a control procedure of a CPU 15 of the receiver 2 in FIG.
4 is an explanatory diagram for explaining the operation of FIG. 1; FIG.
FIG. 5 is an explanatory diagram of a method for calculating an upper bit n2 of a counter value n and a rolling code.
FIG. 6 is a transmission code configuration diagram illustrating a configuration of a conventional transmission code.
[Explanation of symbols]
1 Portable transmitter (wireless device)
2 Receiver (wireless device)
3 Actuator 4 Battery 5 Operation switch for transmission 6, 12 ROM
7,13 EEPROM
8,14 RAM
9,15 CPU
10 Transmitter output 11 Receiver 16 Interface

Claims (2)

Equipped with a transmitter that transmits different transmission codes in response to switch operations, and a receiver that switches the normal codes in a predetermined order in response to changes in the transmission codes in this transmitter. In a wireless device that performs a predetermined output on the receiver side when
The receiver includes at least an ID code, a rolling code, and a counter value related to switch operation as a transmission code,
The rolling code is calculated based on an ID code and a counter value related to a switch operation,
Wherein the counter value according to the switch operation from the transmitter, when it is determined that often exceeds the predetermined range from the number of times of reception of the transmitted code in the receiver, which allowed matching the received number to the number of transmissions A wireless device. The receiver, after allowed matched reception frequency to the transmission count, the radio apparatus according to claim 1, characterized in that for matching of the identification code portion.

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