JP3692843B2 - Automotive door lock control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of a transmitter of a remote control device for operating a door lock of an automobile from the outside of the vehicle. The technical field to which the present invention belongs is sometimes called a wireless door lock or a keyless entry.
[0002]
[Prior art]
As shown in FIG. 9, a normal vehicle door lock control transmitter has a built-in memory for storing a code for counting the number of operations (called a rolling code). Incremented each time a call is made. In transmission, an identification code unique to the transmission device, an encrypted rolling code, operation information including an operation command, and a transmission signal in which transmission information is scrambled are transmitted. The reason why the rolling code is included in the transmission signal is to prevent theft that the transmission signal is intercepted by a malicious other person and the same transmission signal is transmitted later to open the door lock of the automobile.
[0003]
On the other hand, every time the transmission signal is normally received, the decoded rolling code is stored in the memory and is referred to at the next reception as an index of the number of receptions. Therefore, not only the transmission signal is normally decoded, but also it is determined that normal reception has been performed when the value of the rolling code for which the secret code has been resolved is higher than the previous value. Therefore, even if a malicious other person sends the same transmission signal as the previous one, the value of the rolling code is not incremented, so the receiving device does not determine that a normal transmission signal has been received, and theft is prevented. It has become.
[0004]
However, it is often the case that the receiving device could not receive the signal even though the transmission device for controlling the automobile door lock was operated several times. Therefore, in order to cope with such a case, when the rolling code is increased by 2 or more than the previous value, the receiving device side updates the rolling code indicating the number of receptions and updates the transmission signal to be normal. It has come to accept.
[0005]
By the way, when the battery voltage of the automobile door lock control transmitter decreases, the rolling code may not be incremented or written to the memory normally, and the rolling code may not increase from the previous value. In such a case, the receiving device side does not determine that a normal transmission signal has been received, and the operator receives an impression as if the automobile door lock control function has suddenly failed. For the purpose of avoiding such inconvenience, an ordinary automobile door lock control transmitter is provided with a protection circuit for detecting a decrease in battery voltage as shown in FIG. When the protection circuit detects that the battery voltage has dropped below the specified value during operation, the protection circuit notifies the operator of the fact and stops the transmission function.
[0006]
However, since the protection circuit is an analog circuit provided separately from the microcomputer, the provision of the protection circuit inevitably increases the cost and weight and volume of the hardware. Therefore, as a conventional technique, Japanese Patent Laid-Open No. 8-303078 discloses a technique that can prevent a transmission error of a rolling code even when the battery voltage is lowered, without providing a protection circuit, as shown in FIG. It is disclosed.
[0007]
In the memory of this conventional vehicle door lock control transmitter, a plurality of rolling code areas for storing a plurality of rolling codes and a check area for checking a write error in the same area are formed. ing. The check areas are formed in the same number as the plurality of rolling code areas, and each check area corresponds to each rolling code area. Then, the flag of the check area is laid down immediately before the writing to the rolling code area starts, and the flag of the check area is raised immediately after the writing to the rolling code area is finished. Then, when the battery voltage gradually decreases and the rolling code is not written normally because the battery voltage is insufficient for writing to the memory while writing the rolling code to the rolling code area, the flag in the check area goes to sleep. Will remain.
[0008]
Therefore, according to the prior art, it is possible to determine whether the rolling code in the corresponding rolling code area is normal by checking whether the flag in the check area is standing or sleeping. As a result, if it is not normal, it is possible to eliminate the writing error of the rolling code only by reading the previous normal rolling code and adding an appropriate value.
[0009]
[Problems to be solved by the invention]
However, in the above-described conventional technology, there are cases where the operation is effective and cases where the operation is invalid, and it is not always possible to completely eliminate the writing error of the rolling code.
[0010]
In other words, the above-described conventional technique is effective when the battery voltage gradually decreases, the battery voltage is insufficient for writing to the memory while writing the rolling code in the rolling code area, and the rolling code is not written normally. is there. However, it is not effective when the battery voltage fluctuates and writing to the rolling code area is not normal, or when data corruption occurs in the rolling code area due to static electricity or memory charge loss. It was. In other words, since the prior art determines whether the rolling code is correct or not based on the flag in the check area, the conventional technique can effectively prevent a rolling code transmission error against an error that occurs only in the rolling code area. There wasn't.
[0011]
Accordingly, an object of the present invention is to provide an automobile door lock control transmission device that can more reliably eliminate rolling code transmission errors than the prior art.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, the inventors have invented the following means.
[0013]
(First means)
The first means of the present invention is the vehicle door lock control transmitting apparatus according to claim 1 at the beginning of the application . That is, in this means, the memory has a plurality of storage areas in which the number of operations (rolling code) is stored. The operation count adding unit has a cyclic storage logic that cycles through these storage areas and stores the operation count in the memory. On the other hand, the message generation unit has an operation frequency repair logic that appropriately repairs the operation frequency even if an erroneous operation frequency is stored in a part of the storage area of the memory.
[0014]
Here, it is desirable to use a non-volatile memory that does not require a memory holding operation, such as an EEPROM, but other types of memory may be used as long as a rolling code can be stored. Further, in this specification, an operation means including a cyclic storage logic is referred to as an operation number adding unit, and a logical operation means including an operation number repair logic is referred to as a message generation unit.
[0015]
Therefore, in this means, the number of operations (rolling code) is sequentially stored in a plurality of storage areas (rolling code areas) in the memory by the action of the cyclic storage logic of the operation number adding unit. At this time, there is rarely an error in one or several of the plurality of storage areas due to a decrease in battery voltage, garbled data, or the like. However, due to the operation frequency recovery logic of the message generator, even if an incorrect operation frequency is stored in a part of the storage area of the memory, the operation frequency is properly recovered. The operation of the specific operation count repair logic will be described in detail in an embodiment described later. If the operation count repair logic is set appropriately, the wrong operation count is stored in a part of the memory storage area. Even if it is done, the number of operations can be properly restored by the operation of the operation number restoration logic.
[0016]
As a result, unlike the prior art, this means does not require a check area and can reproduce an appropriate rolling code based on the rolling code itself already stored in the rolling code area. Therefore, it is possible to effectively deal with an error that occurs only in the rolling code area, and it is possible to prevent a transmission error of the rolling code. In addition, this means can be implemented only by rewriting the software of the microcomputer incorporated in the transmission device for automobile door lock control, and does not require a protection circuit, and therefore has an advantage that the cost is hardly increased.
[0017]
Therefore, according to the vehicle door lock control transmission device of this means, there is an effect that it is possible to eliminate the transmission error of the rolling code even more surely than the above-mentioned prior art with almost no cost increase. is there. Unlike the above-described normal technique, since a plurality of rolling code areas are rewritten in order, there is an effect that the memory rewrite life is extended even when the number of times of memory rewrite compensation is limited.
[0018]
(Second means)
The second means of the present invention is the vehicle door lock control transmitting apparatus according to claim 2 at the beginning of the application .
[0019]
In this means, since the number of storage areas is three, as described in detail in the embodiment, even if an inappropriate value is stored in the rolling code stored in up to two of the areas, The vehicle door lock control transmitter operates normally. If an incorrect value is written in all three storage areas, it may not work properly and a recovery operation may be required. However, such a case is extremely rare and may occur first. You can say no.
[0020]
Therefore, in practice, the writing error of the rolling code can be almost completely eliminated without requiring a large amount of memory capacity.
[0021]
Therefore, according to this means, in addition to the effect of the first means described above, there is an effect that the configuration having the most excellent cost performance can be obtained.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
The embodiments of the transmission device for automobile door lock control of the present invention will be described clearly and sufficiently in the following examples so that a person skilled in the art can understand that the embodiments can be implemented.
[0023]
[Example 1]
(Configuration of Example 1)
As shown in FIG. 1 together with a corresponding receiver, an automobile door lock control transmission device as Embodiment 1 of the present invention includes a key operation unit 1, an EEPROM 2, an operation count addition unit 3, a message generation unit 4, and a modulation. Part 5 and transmission part 6.
[0024]
Here, the key operation unit 1 is an operation unit that is operated by an operator and specifies desired operation information. The EEPROM 2 stores the number of operations of the key operation unit 1 in a predetermined storage area (rolling code area). Memory. The operation number adding unit 3 is a digital arithmetic unit that increments or updates the operation number stored in the rolling code of the EEPROM 2 for each operation of the key operation unit 1. Similarly, the message generation unit 4 is a digital calculation unit that generates a message including the operation information from the key operation unit 1 and the number of operations (rolling code). That is, the message generation unit 4 is a digital calculation unit that generates a digital signal that scrambles the identification code unique to the transmission device, the encrypted rolling code, the operation information by the operation of the key operation unit 1 and the transmission information. . The operation number adding unit 3 and the message generating unit 4 are realized by software by the same CPU. Further, the modulation unit 5 is a modulation circuit that modulates the message generated by the message generation unit 4 according to a predetermined rule, and the transmission unit 6 transmits the message modulated by the modulation unit 5 on a carrier wave. It is.
[0025]
On the other hand, the receiving device equipped in the automobile includes a receiving unit 16, a demodulating unit 15, a message decoding unit 14, a reception number adding unit 13, an EEPROM 12, and a driving unit 11, and a door lock or the like according to a message received from the transmitting device. Drive. At this time, the reception number adding unit 13 has a function of incrementing the rolling code stored in the single rolling code storage area in the EEPROM 12 every time the message is normally received. Further, when the rolling code included in the received and decoded message is larger than the predicted value, the reception number adding unit 13 updates the rolling code stored in the EEPROM 12 and updates the rolling code on the transmission device side. It also has a function to synchronize with. On the other hand, when the rolling code received this time is not larger than the rolling code received normally last time, the message decrypting unit 14 determines that an illegal signal has been received and prevents the receiving apparatus from reacting. Has a security function.
[0026]
As shown in FIG. 2, in the automobile door lock control transmitting apparatus of the present embodiment, the EEPROM 2 has three storage areas (rolling code areas) (1), (2), It has (3). The operation count adding unit 3 (see FIG. 1) has a cyclic storage logic that cycles through these storage areas and stores the operation count (rolling code) in the EEPROM 2. On the other hand, the message generator 4 (see FIG. 1) properly restores the number of operations even if the number of erroneous operations is stored in some of the storage areas (1), (2), and (3) of the EEPROM 2. Has operation frequency repair logic. The operation of the operation frequency repair logic and the like will be described in detail in the next section of operation and effect.
[0027]
(Operational effect of Example 1)
Since the vehicle door lock control transmitter of this embodiment has the above-described configuration, it operates as follows.
[0028]
That is, the number of operations (rolling code) is sequentially stored in three storage areas (rolling code areas) (1), (2), and (3) in the EEPROM 2 by the operation of the cyclic storage logic of the operation number adding unit 3. Has been. At this time, it is rare that an error occurs in one or several of the plurality of storage areas due to a decrease in the battery voltage or data corruption. However, even if an incorrect rolling code is stored in some of the rolling code areas (1), (2), (3) of the EEPROM 2 due to the operation of the operation frequency recovery logic of the message generator 4, the rolling code is It is repaired properly. Hereinafter, the repairing action of the rolling code will be described for each case.
[0029]
First, as shown in FIG. 3, when a normal rolling code is stored in all of the rolling code areas (1), (2), and (3), the largest stored value is transmitted. Used for. Thereafter, this rolling code is incremented to increment the value and stored in the next rolling code area. That is, in the case of FIG. 3, since values of 8, 9, and 10 are stored in the order of (1), (2), and (3) in each rolling code area, all are read once and rolled. Check that the code is normal. When the confirmation is obtained, the largest value 10 stored in the rolling code area {circle around (3)} is used for transmission before being incremented to 11, and stored in the next rolling code area {circle around (1)}.
[0030]
Next, as shown in FIG. 4, if there is an error in one of the rolling code areas {circle over (1)}, {circle over (2)}, {circle over (3)}, a serial number or a jump is made according to the writing order of the rolling code area. Contains rolling code. This can be easily determined by reading each rolling code from all the rolling code areas. In this case, the larger one of the serial numbers or the skipping rolling code is used for transmission. However, if it is determined that there is an error in the previously stored rolling code area, the larger one of the consecutive rolling codes is incremented to be a transmission rolling code. Then, the erroneous rolling code area is restored, and the rolling code used for the current transmission is incremented and stored in the next rolling code area. By performing such an operation, even if there is an error in one of the rolling code areas {circle over (1)}, {circle over (2)}, {circle over (3)}, the vehicle door lock control transmitter of this embodiment It is possible to correct normal operation.
[0031]
Furthermore, as shown in FIG. 5, there is a possibility that there are errors in two areas of the rolling code areas {circle around (1)}, {circle around (2)} and {circle around (3)} very rarely. In this case, after all the rolling codes are read out, the largest rolling code among them is incremented regardless of whether it is correct or not to be a transmission rolling code. Then, as described above, if the received rolling code is larger than the predicted value, the receiving device has a function corresponding to the jump update, and thus the receiving device functions normally. The rolling code area in the next order stores a value obtained by incrementing the maximum rolling code, and two of the three rolling codes are serial numbers. This is equivalent to the case where there is an error in one of the above-mentioned rolling code areas {circle over (1)}, {circle over (2)}, {circle around (3)}.
[0032]
Similarly, although it does not happen first, assuming that there is an error in all of the three rolling code areas, the maximum rolling code is transmitted in the same manner as in the case where there is an error in the above two areas. used. Then, with a probability of approximately one-eighth, the transmitted rolling code is larger than the rolling code expected by the receiving device, so the receiving device usually operates normally. In rare cases, a rolling code smaller than the rolling code expected by the receiving device may be stored in all of the erroneous rolling code areas. In this case, the door is manually opened to perform a reset operation. Can be done. In any case, it can be said that such a case does not occur probabilistically first, so there is no inconvenience in actual operation.
[0033]
Finally, as shown in FIG. 6, there is a possibility that the same value is stored in all rolling code areas, although it does not happen first. Even in such a case, there is no particular problem if the transmission device is used after the operator performs the reset operation. However, when used without performing a reset operation, the value of the rolling code area (1) is used for transmission, and then incremented and stored in the rolling code area (2).
[0034]
In the above description, it has been clarified what operations are performed in the rolling code areas (1), (2), and (3) in all cases. Next, the main points of the overall operation of the transmission device for automobile door lock control of this embodiment will be described with reference to the flowchart of FIG.
[0035]
First, when the key operation unit 1 is operated, the logic starts. In processing step S1, three rolling code values are read from all of the rolling code areas (1), (2), (3) of the EEPROM 2. . In step S2, it is determined whether or not all three rolling codes have values arranged in a normal order. If it is determined that the three rolling codes are normal, the largest rolling of the three is determined in processing step S3. The code is encrypted for transmission.
[0036]
Conversely, if it is determined in decision step S2 that all three rolling codes are not normal, the logic proceeds to decision step S4 and whether or not two of the three rolling codes are normal. Is determined. As a result, if it is determined that up to two are normal, the larger one of the two normal rolling codes is encrypted for transmission in processing step S5. In step S5, if it is determined that the rolling code to be encrypted is not the previously stored value, the rolling code is incremented and then encrypted for transmission. However, since it is sufficient to perform the operation twice even if there is no such determination action and increment action, it is not always necessary and may be omitted from the logic.
[0037]
Conversely, if it is determined in decision step S4 that even two of all the rolling codes are not arranged in the normal order, the logic proceeds to decision step S6 and all three rolling codes have the same value. It is determined whether or not. If it is determined in the determination step S6 that all three rolling codes have the same value, the rolling code stored in the rolling code area (1) is encrypted for transmission in the processing step S7. Otherwise, the logic proceeds to process step S3, where the largest rolling code among the three different ones is encrypted for transmission as described above.
[0038]
After the proper rolling code has been encrypted for transmission as described above, the logic proceeds to successive processing steps S8-S11. That is, each operation of reading the identification code from the identification code area of the EEPROM 2, generating a message, transmitting the message, and incrementing the rolling code adopted for transmission and storing it in the next rolling code area is performed in order. Is called. In this way, the message is transmitted and the rolling code area is updated.
[0039]
On the other hand, as shown in FIG. 8, the logic of the receiving apparatus starts when a message from the transmitting apparatus is received. First, in a decision step S21, parity check, CRC, etc. are performed, and it is confirmed that there is no transmission error. The In step S22, the identification code is read from the identification code area of the EEPROM 12 (see FIG. 1). In the determination step S23, the identification code is compared with the received identification code and received from the transmission device specific to the car. Confirmed to be a message. Then, in the processing step S24, the rolling code received normally last time is read from the rolling code area of the EEPROM 12, and in the judgment step S25, it is confirmed that the rolling code received this time is larger than the previous value. Finally, in processing step S26, the currently received rolling code is written into the rolling code area of the EEPROM 12, and in step S27, a door lock operation is performed according to the operation information in the received message.
[0040]
Conversely, if it is determined that there is an abnormality in any of the determination steps S21, S23, and S25 among the above processes, the receiving apparatus determines that a normal message has not been received. As a result, in the receiving apparatus, the rolling code is not updated and no operation is performed.
[0041]
As described above in detail, in the automobile door lock control transmission device of this embodiment, even if there is an error in some of the three rolling code areas of the EEPROM 2 (see FIG. 1), the operation frequency recovery logic operates. A proper rolling code is transmitted. As a result, the vehicle door lock control transmission device of this embodiment does not require a check area unlike the prior art, and transmits an appropriate rolling code based on the past rolling code itself stored in the rolling code area. can do. Therefore, it is possible to effectively deal with an error occurring only in the rolling code area, and to prevent a rolling code transmission error. In addition, the present embodiment can be implemented only by rewriting the software of the microcomputer incorporated in the transmission device for automobile door lock control, and does not require a protection circuit unlike the conventional technique, so that there is an advantage that the cost is hardly increased. It also has.
[0042]
Therefore, according to the transmission apparatus for automobile door lock control of the present embodiment, there is an effect that the transmission error of the rolling code can be more surely eliminated with almost no cost increase. In addition, since the three rolling code areas are rewritten in order, there is an effect that the rewriting life of the EEPROM 2 is tripled as compared with the above-described normal technique that uses only one rolling code area.
[Brief description of the drawings]
FIG. 1 is a block diagram showing the configuration of an automobile door lock control transmitting device as a first embodiment together with the receiving device. FIG. 2 is a schematic diagram showing the configuration of a rolling code area in the first embodiment. Schematic diagram showing the operation of the message generator, etc. in Example 1 [FIG. 4] Schematic diagram showing the operation of the message generator, etc. in Example 1. [FIG. 5] Schematic diagram showing the operation of the message generator, etc. in Example 1 [FIG. FIG. 6 is a schematic diagram showing the operation of the message generation unit and the like in the first embodiment. FIG. 7 is a flowchart showing the operation of the automobile door lock control transmitting device as the first embodiment. FIG. 9 is a schematic diagram showing the operation of the memory in the conventional technology. FIG. 10 is a schematic diagram showing that the normal technology has a protection circuit. Schematic diagram illustrating that there is no circuit protection EXPLANATION OF REFERENCE NUMERALS
1: Key operation unit (as operation unit) 2: EEPROM (as memory)
3: Operation count addition unit 4: Message generation unit 5: Modulation unit 6: Transmission unit

Claims (2)

An operation unit that is operated by an operator to specify desired operation information, a memory that stores the number of operations of the operation unit in a predetermined storage area, and the number of operations stored in the storage area An operation count addition section that increments for each operation, a message generation section that generates a message including the operation information and the operation count, a modulation section that modulates the message according to a predetermined rule, and the modulated message A transmission device comprising a transmission unit for transmitting on a carrier wave ;
A receiving device that is mounted on an automobile and includes a receiving unit, a demodulating unit, a message decoding unit, a reception number adding unit, an EEPROM and a driving unit, and driving a door lock according to the message received from the transmitting device;
In an automobile door lock control device having
Among the transmission devices,
The memory has three storage areas in which the number of operations is stored,
The operation number adding unit has a cyclic storage logic that circulates the storage area and stores the operation number in the memory.
The message generation unit has operation number repair logic for properly repairing the operation number even if the operation number is stored in a part of the storage area of the memory.
This operation number repair logic has the effect that if there are errors in two or all of these storage areas, the maximum one of all the operation times is incremented to be the number of operations for transmission. Mochi,
Of the receiving device, the reception number adding unit is,
A function of incrementing a rolling code stored in a single rolling code storage area in the EEPROM each time the message is normally received;
Further, when the rolling code included in the received and decoded message is larger than the predicted value, the rolling code stored in the EEPROM is skipped and updated to synchronize with the rolling code on the transmitter side. It has a function ,
Automobile door lock control device . The operation number repair logic has an operation of incrementing a larger one of the number of operations of serial numbers or skipping one to make the number of operations for transmission when there is an error in one of the three storage areas. have,
The automobile door lock control device according to claim 1.

Images