JP2012222466A - Multiplex communication device and multiplex communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multiplex communication device and a communication control method that do not cause a problem regarding robustness or a high-speed property if fixing has occurred in an exclusive message box.SOLUTION: An electronic control device 1 that is connected to a LAN employing the CAN protocol and causes display units D1 and D2 to display information comprises: a plurality of exclusive message boxes ch1, ch2, and ch3 for accommodating messages which are communication contents for each frame; a plurality of empty message boxes which become alternative means of the plurality of exclusive message boxes; means for checking fixing of the exclusive message boxes in a stage before communication; and means for rewriting an empty message box from disable (D) to enable (E) when an exclusive message box has become a fixing state to make an alternative message box for the fixed exclusive message box.

Description

  The present invention relates to a multiplex communication apparatus and a multiplex communication method capable of realizing accurate communication even when a message box that accommodates data of communication contents (messages) divided for each frame in multiplex communication is stuck due to a hardware failure. It is about. In particular, the present invention relates to a multiplex communication apparatus and a multiplex communication method applied to a vehicle information providing apparatus including an instrument that displays a vehicle state in a vehicle to a driver.

  As conventional techniques, the following techniques are implemented in CAN communication for automobiles. Message boxes are used for sending and receiving messages in the CAN macro. This message box is made up of registers and stores information consisting of a set of 01s.

  However, when the written data is read, there may occur a sticking (a failure in which the signal level is hardened) that 1 should be read as 0 or 0 should be read as 1.

  Therefore, in general, it is checked before starting the message communication whether or not it is stuck due to a hardware failure. When the sticking occurs, the corresponding message box is not used as fail-safe control for not transmitting / receiving abnormal data. Alternatively, control such as stopping the function of CAN communication itself is performed.

  For example, in Patent Document 1, in the ECU (electronic control unit) on the receiving side, the communication controller receives data from the multiplex communication bus, and transmits the received data for each packet using a CRC check code, sum check data, or the like. Checking whether there is any abnormality above. If there is no transmission error in normal communication, the data is stored in the reception data memory in the communication controller, and if abnormal, processing such as requesting transmission is performed again.

Japanese Patent No. 3639455

  However, the inventor has paid attention to such a problem that robustness or high-speed performance is insufficient such as communication itself cannot be performed or communication processing is delayed. In addition, in a situation where sticking occurs, even if retransmission is requested, the situation may not be improved.

  In particular, in the vehicle information providing apparatus including a speedometer that displays the vehicle state in the vehicle to the driver and an indicator that displays an important failure or warning matter, it is not preferable that such communication failure or delay occurs. .

  Vehicle speed meter, fuel gauge, engine water temperature gauge, fuel level warning light, seat belt warning light, half door warning light, engine warning light, charging warning light, hydraulic pressure warning light, brake warning light, SRS airbag / pretensioner warning light It is desired that the indicator display including the ABS & brake assist warning light etc. provides the driver with accurate and high-speed information.

  For example, it is preferable to avoid a situation where the vehicle speedometer stops working or an indicator that displays a dangerous state cannot be displayed immediately. In such a case, in the conventional control described above, for example, in the case of an indicator, it is displayed on the active side, and the concept of fail-safe is applied. However, it is actually not desirable for the indicator to display danger on the active side even though it is not dangerous.

  The present invention has been made by paying attention to such problems existing in the prior art, and its purpose is to be achieved even when data sticking occurs in a message box that accommodates transmitted data. It is an object of the present invention to provide a multiplex communication apparatus and a multiplex communication method that do not cause a problem of robustness such as that communication itself cannot be performed or a delay in communication processing, or a problem of high speed.

  Descriptions of patent documents listed as prior art can be introduced or incorporated by reference as explanations of technical elements described in this specification.

  In order to achieve the above object, the present invention employs the following technical means. That is, according to the first aspect of the present invention, information is displayed on a multiplex communication line that multiplexes communications by dividing the content received for each frame, and an information providing device that displays the status of devices connected to the multiplex communication line. An electronic control device connected to the multiplex communication line, and the electronic control device is assigned with a plurality of messages for each frame, which is a content of communication from the transmission side to the reception side, and the assigned message Is stored in a dedicated message box consisting of a plurality of registers for storing data, an empty message box consisting of registers to which messages for communication for each frame are not assigned, and a dedicated message box before communication By the sticking check means that checks whether the data is stuck or not, and the sticking check means Wear check result, when the data in the dedicated message box is determined to be fixed, an empty message box, is characterized by having a setting unit for setting as an alternative message box dedicated message box data is secured.

  According to the present invention, even if data sticking occurs in a message box, an empty message box to which no message serving as communication content for each frame is assigned is used as an alternative message box for the dedicated message box to which data is stuck. Since it is set, communication is not interrupted and no reception error occurs, so that it is possible to obtain a multiplex communication apparatus that can reliably receive information.

  According to the second aspect of the present invention, in the electronic control device, the first message and the second message to which different dedicated message boxes are assigned among the plurality of messages are synchronized between the transmission side and the reception side. It is characterized by being received at no asynchronous timing.

  According to the present invention, the first message and the second message are received at an asynchronous timing. Therefore, between the first message at the time of reception and the next first message, the second message and the next message are received next. Even if a sufficient time can be set between the two messages, the time between the first message and the second message may be nearly 0 seconds. However, in the reception of the present invention, since different message boxes are assigned to the first message of one frame and the second message of one frame, the time between the first message and the second message is almost 0 seconds. Even in a case close to, message data can be accommodated at high speed in different message boxes.

  According to a third aspect of the present invention, the electronic control device includes a meter electronic control unit that controls the vehicle information providing device that forms the information providing device, and includes vehicle operation information and device operation information. The situation is displayed on the vehicle information providing apparatus in the vehicle.

  According to the present invention, since the electronic control device is a meter electronic control unit (meter ECU) that controls the vehicle information providing device, the following effects can be obtained. The meter ECU must execute communication processing from many devices distributed in the vehicle at a high speed even though a high-class microcomputer is not used. However, according to the present invention, when one message box is assigned to a message of one frame, and when data sticking occurs in the mailbox, an alternative message box is assigned. It can be received at high speed without error, and the received data is less likely to be garbled or impossible to receive. Therefore, the correct vehicle status can be displayed at high speed to the vehicle driver, leading to safe driving.

  In the invention according to claim 4, the electronic control device includes a transport machine information providing device for displaying the status of the transport machine, a factory monitoring information providing device for displaying the status of the device in the factory, and the status of the machine tool. It is characterized by comprising an electronic control unit for any one of the information providing apparatus for machine tools that displays.

  According to the present invention, the present invention is applied to multiplex communication in an electronic control unit for any one of a transport machine information providing apparatus, a factory monitoring information providing apparatus, and a machine tool information providing apparatus. Therefore, the following effects can be obtained. This type of electronic control unit has to execute many processes at high speeds without using a high-end microcomputer. However, as in the present invention, when one message box is assigned to a message of one frame, and when data sticking occurs in the mailbox, an alternative message box is assigned. It can be received at high speed without error, and the received data is less likely to be garbled or impossible to receive. Therefore, correct device information can be displayed at high speed to the driver of the device.

  In the invention according to claim 5, the electronic control unit has storage means for storing in advance the position information of the register that becomes the empty message box, and the storage means stores the empty message box in the data fixed state. The position information is updated every time the setting means sets as a substitute message box for the generated dedicated message box.

  According to the present invention, each time an alternative message box is set, the storage means updates the register position information that becomes an empty message box. Therefore, the empty message box is replaced with the alternative message box of the dedicated message box to which the data is fixed. When set as, it is not necessary to search for an empty message box, and communication processing can be performed at high speed.

  In the invention according to claim 6, the electronic control device is set with an individual acceptance mask corresponding to each frame, and the electronic control device is configured to accept the acceptance mask assigned to the dedicated message box. The dedicated message box stores the data of the corresponding message of each frame, and the sticking check means checks the register that becomes each dedicated message box in order, and the sticking check results in the register of the dedicated message box to which the data is stuck. If it is determined that there is a dedicated message box related to the register where the sticking has occurred, an acceptance mask for the empty message box is set. Special message box. It is set to.

  According to the present invention, when a message box to which data is fixed is found, an acceptance mask for the message box to which the data is fixed is set for an empty message box, and there is no message box to which the data is fixed. If it is determined, the acceptance mask is set for a predetermined dedicated message box, so that even if there is a message box to which data is fixed, high-speed communication is possible.

  In the invention according to claim 7, when all the empty message boxes are set as alternative message boxes for the dedicated message box, the electronic control unit sets the empty message box before the dedicated message box to which the data is fixed is found. A warning display signal indicating that there is no message box is issued.

  According to this invention, measures such as repairing a dedicated message box can be urged before falling into communication, and the state of the device is accurately displayed on the information providing device to ensure further safety. Can do.

  In the eighth aspect of the invention, the electronic control unit, when all the empty message boxes are replaced with the dedicated message box, causes a new message when the data relating to the dedicated message box is newly fixed. A warning display signal indicating that there is no box is generated.

  According to the present invention, after all of the empty message boxes are finally replaced with the dedicated message box, a warning message indicating that there is no empty message box is displayed when a new dedicated message box is stuck. Since it is out of service, communication failure will occur, but the failure status can be displayed, so it is possible to take measures such as repairing the message box early, and display the device status accurately on the information providing device, Safety can be ensured. Further, when the degree of occurrence of data sticking is small, it is possible to delay the output of the warning display signal until the last minute.

  According to the ninth aspect of the present invention, in an electronic control unit connected to a multiplex communication line for performing information display on an information providing device for displaying the status of a device and dividing the content received for each frame and performing multiplex communication , A plurality of messages that are the contents of communication from the transmission side to the reception side for each frame are assigned, and this is an alternative to a dedicated message box consisting of a plurality of registers for storing data of the assigned messages. A plurality of empty message boxes are set in advance, a sticking check is performed to check whether the data stored in the dedicated message box is not stuck, and if the data is stuck, one of a plurality of empty message boxes as an alternative means Set as an alternative message box for the dedicated message box where data is stuck. It is characterized in that.

  According to the present invention, even if data sticking occurs in a message box composed of registers, an alternative message box is set, so that communication is not interrupted or a reception error does not occur. A multiplex communication method in which information is received can be provided.

  In the invention according to claim 10, the electronic control device has a microcomputer in the electronic control device, and when the microcomputer is turned on, the microcomputer enters the first transition state, and the first transition In the initialization process, the sticking check is performed in the initialization process, and when the initialization process is completed, the microcomputer enters the second transition state which is a normal communication state. When there is no need for communication, the microcomputer enters the bus transition state of the third transition state, and in the third transition state, an operation is performed on a device connected to the electronic control unit via the multiple communication line. When the microcomputer returns to the first transition state and the microcomputer sleeps in the third transition state Microcomputer, is characterized in that a sleep state is shifted to the fourth transition condition.

  According to the present invention, the initialization process is performed first, and then the communication is started. Therefore, it is possible to perform the data sticking check on the message box at the preparation stage for starting the communication, and reliable communication is ensured. Done. In addition, when an operation is performed on the device in the third transition state, the operation returns to the first transition state. For example, when the driver starts driving with a key switch on and after that, the door is opened. When there is an action on a device such as the above, it is possible to perform a data sticking check on the message box at the preparation stage for starting communication.

  In the invention described in claim 11, an individual reception mask corresponding to each frame is set in the electronic control unit, and each of the corresponding message boxes corresponding to the dedicated message box is set according to the reception mask assigned to the dedicated message box. Frame message data is stored in a dedicated message box, and the sticking check sequentially checks the registers that become each dedicated message box. As a result of the sticking check, it is determined that there is a dedicated message box register to which the data is stuck. Then, the acceptance mask setting for the dedicated message box related to the register where the sticking has occurred is performed for the empty message box, and if it is determined that there is no dedicated message box to which the data is stuck, the acceptance mask setting is set. What to do with a dedicated message box It is characterized in.

  According to the present invention, when a message box to which data is fixed is found, an acceptance mask for the message box to which the data is fixed is set for an empty message box, and there is no message box to which the data is fixed. If it is determined, the acceptance mask is set for a predetermined dedicated message box, so that even if there is a message box to which data is fixed, high-speed communication is possible.

  In the invention described in claim 12, after setting all the empty message boxes as alternative message boxes for the dedicated message box, there is no empty message box before the dedicated message box to which the data is fixed is found. The electronic control device emits a warning display signal.

  According to this invention, measures such as repairing a dedicated message box can be urged before falling into communication, and the state of the device is accurately displayed on the information providing device to ensure further safety. Can do.

  In the invention described in claim 13, after all the empty message boxes are replaced with the dedicated message box, when the data relating to the dedicated message box is newly fixed, there is no empty message box. The electronic control device emits a warning display signal.

  According to the present invention, after all of the empty message boxes are finally replaced with the dedicated message box, a warning message indicating that there is no empty message box is displayed when a new dedicated message box is stuck. Since it is out of service, communication failure will occur, but the failure status can be displayed, so it is possible to take measures such as repairing the message box early, and display the device status accurately on the information providing device, Safety can be ensured. Further, when the degree of occurrence of data sticking is small, it is possible to delay the output of the warning display signal until the last minute.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view showing an outline of a vehicular information providing apparatus adopting multiplex communication to which a CAN is applied in a first embodiment of the present invention. It is a block block diagram of the information provision apparatus for vehicles of FIG. 1 in the said embodiment. It is a schematic block diagram regarding CAN in the electronic control unit for meters which employ | adopted the multiplex communication which applied to the said embodiment and applied CAN. It is a soft state transition diagram in the control means in ECU for meters of the above-mentioned embodiment. It is a flowchart including the sticking check process of a message box which is one of a series of processes in the initialization process in the embodiment. It is explanatory drawing which shows the outline | summary of the read / write check in the said embodiment. It is explanatory drawing explaining the state which substitutes an exclusive message box for an empty message box in the said embodiment. In the said embodiment, it is explanatory drawing explaining the reception timing of a message.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration.

  Not only combinations of parts that clearly indicate that the combination is possible in each embodiment, but also the embodiments are partially combined even if they are not clearly specified unless there is a problem with the combination. It is also possible.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. Even if the message box of the CAN hard macro (CAN macro) built in the microcomputer is fixed due to a hardware failure including a register in the controller area network (CAN), the first embodiment The present invention relates to a multiplex communication apparatus and a multiplex communication method for realizing normal message transmission / reception using an empty (unused) message box.

  In particular, the present invention relates to a multiplex communication apparatus and a multiplex communication method applied to a vehicle information providing apparatus including an instrument that displays a vehicle state in a vehicle to a driver. FIG. 1 is a front view showing an outline of a vehicular information providing apparatus adopting a multiplex communication apparatus to which a CAN according to the present embodiment is applied.

  In FIG. 1, a vehicle information providing device 100 provided on an instrument panel in front of a driver in a vehicle includes first and second display means (display units) D1 and D2, an alarm display device (indicator) 20, Consists of.

  The first display means D1 includes a liquid crystal display panel such as TFT, an organic EL panel, and the like, and is a multi-display that displays vehicle speed and the like. A part of the alarm display device in the instrument panel according to the present invention is also configured in the multi-display, and the other part is configured by a plurality of alarm display devices (indicators) 20.

  The 2nd display means D2 consists of a pointer type display part (instrument) provided with the pointer | guide and index plate which are mentioned later. 30 is a first pointer type display unit made up of an engine tachometer, 320 is a sounding body, 40 is a second pointer type display unit made up of a fuel gauge, and 50 is a third pointer type display unit made up of a thermometer. It is.

  FIG. 2 is a block diagram of the vehicle information providing apparatus 100 of FIG. The configuration includes a vehicle information terminal 200 and a multiplex communication input / output terminal 210 for inputting / outputting vehicle information, and a vehicle interface (vehicle I / F) means 230.

  Furthermore, a control means 250 for controlling the vehicle information providing apparatus 100, a storage means 26 comprising a ROM or the like for storing a processing program, display control for the display means D1, each pointer type display unit 30, 40, 50, and A control output unit 270 that transmits a control output to the alarm display device (indicator) 20 to perform control, and an auditory information provision unit 290 that performs auditory display of various information.

  The auditory information providing unit 290 includes a sound / speech synthesis unit 300 that reproduces sound / sound, and an amplifier 310 that amplifies an output signal (sound / speech output signal) from the sound / speech synthesis unit 300. The sound generator (speaker) 320 outputs the amplified signal from the amplifier 310 as an alarm sound, and the sound guide section 330 that guides the sound emitted from the sound generator 320.

  Furthermore, the vehicle information providing apparatus 100 includes a travel control apparatus 410 including another ECU (electronic control unit) such as an engine control apparatus via a multiplex communication line 400 that forms a signal line such as a CAN bus of the multiplex communication apparatus, It is connected to operation means 420 including various operation switches.

  Next, the operation of the vehicle information providing apparatus 100 in FIG. 2 will be described. The control means 250 obtains vehicle status related to travel control, alarm information, and information related to operation from the vehicle information terminal 200 and the multiple communication input / output terminal 210 that input and output vehicle information.

  Based on this acquired information, vehicle status notification, alarm output, guidance on operation, and answerback are notified through sound generator 320 of auditory information providing means 290 with sound effects and voice. At the same time, the image is displayed on the display means D1 (FIG. 1). Further, necessary alarm display is performed by an alarm display device (indicator) 20.

  Here, the operation at the time of input / output of the control means 250 will be described by taking alarm information as an example. The control means 250 obtains information about the vehicle from the vehicle information terminal 200 for inputting / outputting vehicle information and the multiplex communication input / output terminal 210, and determines whether there is a warning generation condition based on this information. .

  When a warning occurrence condition is detected, the warning information is notified by sound effects and sound by the auditory information providing means 290, and the display form related to the warning information is displayed by the display unit D1 or the alarm display device (indicator) 20. To do.

  For example, when a detection signal indicating that the seat belt is not attached is input via the vehicle information terminal 200 or the multiplex communication input / output terminal 210, the control unit 250 displays an image and sound after the sound effect “Pawn”. The display unit D1 and the auditory information providing means 290 are controlled so as to output “Please wear your seat belt”.

  The control means 250 in the instrument control device uses the vehicle speed signal SSg input to the control means 250 through the multiplex communication line 400 in order to determine that the vehicle has stopped. That is, a vehicle stop signal is generated from the vehicle speed signal SSg. The vehicle speed signal SSg is a signal that is input from the traveling control device 410 to the control unit 250 and used for vehicle speed display using the first display unit (display unit) D1.

  In addition, the control means 250 in the instrument control device determines that the engine has stopped, the “engine stop signal ESSg or engine speed signal ERSg input from the multiplex communication line 400 in the control means 250. Utilizes the engine control signal consisting of

  Among these, the engine speed signal ERSg is input to the control means 250 from the travel control device 410, and is an existing signal used for displaying the engine speed on the display unit D1 or the pointer type display unit 30 (FIG. 1). It is.

  The engine stop signal ESSg is a signal used for displaying the engine stop, which is displayed on the liquid crystal screen of the display unit D1 as “idling stop is in progress”. The engine stop signal ESSg is displayed so as to determine whether the engine is stalled or the engine is intentionally stopped (whether idling is stopped).

  Next, the multiplex communication to which CAN used for the vehicle information presentation apparatus 100 of FIG. 2 is applied will be described. First, an outline will be described before detailed description. The inventor paid attention to the following points. In the CAN communication related to the meter display for vehicles (displays for the 30, 40, 50, D1, and 20 parts in FIG. 1), message boxes are not normally used as a single message box, but a plurality (for example, 16, 62, 62). In many cases, there is a fact that only 1/3 or half of a plurality of message boxes are used.

  One message box is controlled to store only the contents of one frame. In other words, if (ch1) of the message box stores the content (X), it is set as a dedicated message box for the content (X). The content (Y) is stored in (ch2), which is a dedicated message box for the content (Y). The content (Z) is stored in (ch3), which is a dedicated message box for the content (Z).

  In such a state, when the dedicated message box (ch3) of the content (Z) is fixed, there is an empty message box, so that the empty message box is newly used as the dedicated message box of the content (Z). From now on, we will use this new dedicated message box.

  Hereinafter, the first embodiment will be described in more detail with reference to FIGS. FIG. 3 shows a meter ECU (electronic control unit for an instrument or indicator stored in an instrument panel in a vehicle) 1 used in the first embodiment and connected to a LAN using a CAN protocol. FIG.

  The meter ECU 1 includes the vehicle interface (vehicle I / F) means 230, the control means 250, the control output means 270, and the storage means 26 shown in FIG.

  The meter ECU 1 includes a CAN controller 3 built in a microcomputer 2 and a CAN transceiver 4 for transmitting and receiving a frame generated by the CAN controller 3 via a CAN bus 10.

  The CAN controller 3 includes a plurality of message boxes 5 for storing messages transmitted and received between the meter ECU 1 and other ECUs (such as the travel control device 410 in FIG. 2). Although only one is shown in FIG. 3 for convenience, the message box 5 is an aggregate of a plurality of dedicated message boxes and empty (unused) message boxes.

  In addition, a transmission control unit 6 that frames a message based on the setting value of the message box 5 and transmits the frame to the CAN bus 10 via the CAN transceiver 4 is provided. Further, it has a reception control unit 7 that receives a frame via the CAN transceiver 4 and extracts a message. These transmission control unit and reception control unit are collectively shown as transmission / reception control units 6 and 7.

  Bus arbitration control (bit-by-bit non-destructive arbitration) when a frame collides on the CAN bus 10, error detection and notification related to frame transmission / reception, and communication control according to the CAN protocol The CAN protocol control unit 8 is provided as communication control means for executing the above.

  Note that the notification or the like refers to notifying the software side of “received now” or “now transmitted”. Based on the notification “received now”, processing such as going to the message box 5 for the received content is performed.

  FIG. 4 is a soft state transition diagram in the control means 250 in the meter ECU 1 of FIG. In FIG. 4, when the power source of the microcomputer in the control means 250 is turned on, the first transition state T1 is entered. In the first transition state T1, an initialization process state is entered, and an initialization process (initialization process) is performed.

  In this initialization process, a RAM used in the software is initialized, and resources (hardware) in the microcomputer are initialized. The initialization of the resources of the microcomputer includes the initialization of the CAN hard macro (CAN macro). During initialization of the CAN hard macro (CAN macro), it is also checked whether the message box 5 in the register is stuck.

  FIG. 5 is a flowchart including the sticking check process for the message box 5 in the register, which is one of a series of processes in the initialization process in the first embodiment. In FIG. 5, when the initialization process starts, in step S401, the message box 5 in the register is checked for sticking.

  This sticking check sequentially checks the inside of the message box 5. As a result, if a stuck “dedicated message box in the register” is found, that is, if there is a sticking check NG dedicated message box, the process proceeds to step S403 when it is determined in step S402.

  In step S403, an acceptance mask (corresponding to the information destination, address or nameplate) for the dedicated message box at the time of sticking check NG is set for the message box in the vacant register.

  If it is determined in step S402 that there is no fixed dedicated message box, the process proceeds to step S405, and the acceptance mask setting for the dedicated message box at the time of the sticking check OK (GO) is set to a predetermined original dedicated message box. To do.

  Next, in step S404, other initialization processing is performed, and a series of initialization processing ends. In other words, in this step S404, other initial values after the sticking check and the acceptance mask are set for the dedicated message box in the register in the series of initialization processes in the first transition state T1 in FIG. Is being processed.

  The order of processing in step S404 may be reversed. That is, the initialization process in step S404 may be performed before step S401. The receiving mask is also called an ID mask and is well known.

  When the initialization process is completed, the second transition state T2 that is the normal state of communication is entered in FIG. In the second transition state T2, when there is no need for communication, a Bus Sleep (bus sleeve) condition is satisfied, and a Bus Sleep (bus sleeve) state of the third transition state T3 is established.

  In this transition state 3, if there is an action in the vehicle such as opening the door of the vehicle, the CAN activation condition is satisfied and the process returns to the first transition state T1. In the third transition state T3, when the microcomputer finally goes to sleep, the microcomputer sleep (sleep) condition is satisfied and the state transitions to the fourth transition state T4 to enter the sleep state.

  Note that the dedicated message box can be used for both reception setting and transmission setting. When the dedicated message box is used in the reception setting, in order to receive only a specific message, an acceptance mask is set as a setting value of the dedicated message box for each message ID in the message.

  For example, in order to receive only the frame with the message ID “600”, “600” is set as the acceptance mask setting of the dedicated message box. As a result, only the message with the message ID “600” is stored in the set dedicated message box.

  The dedicated message box can also be used for transmission. For each dedicated message box, it can be assigned for transmission (can only be used in transmission settings), or can be assigned for reception (used only in reception settings). Can not)

  Also, before starting the operation of CAN communication, as described above, the hardware failure (adherence) of the dedicated message box is checked. Note that a known method can be used for this sticking check. In addition, the sticking check is not performed all the time, but basically when the driver turns on the key switch and starts driving, or when there is an action such as opening the vehicle door, Since the communication is started, the sticking check of the dedicated message box is performed at the preparation stage for starting the communication at that time.

  In this sticking check, for example, a value such as “AA55, 55AA” is written, and then the read / write check is performed by reading the value. If a value that matches the written value cannot be read, control is performed to prohibit the use of the corresponding dedicated message box as a hardware failure.

  In this case, it becomes impossible to correctly receive the message received in the dedicated message box that has been disabled. Note that writing / reading a value such as “AA55, 55AA” (values “A” and “5”), and then reading it, has already been performed.

  FIG. 6 is an explanatory diagram showing an outline of the read / write check in the first embodiment. In FIG. 6, “A5” is written to and read from the 8-bit register, and then “5A” is written and read. It is possible to check that there is no sticking to all the bit positions if these readings are normally performed from the arrangement of the bits 01 having the values of “A” and “5”.

  Therefore, if it is determined that there is a problem (NG) in the write / read check of the dedicated message box, a corresponding acceptance mask is set in an empty (unused) message box, and the message box receives the message. Set up to do. As a result, a message that would otherwise be unreceivable can be received in the alternative dedicated message box. This will be described in detail below.

  FIG. 7 is an explanatory diagram illustrating a state in which the dedicated message box in the first embodiment is replaced with an empty message box. In FIG. 7, for example, 16 dedicated message boxes are called ch (channel) 1, ch2, and ch3. In this case, the message M0 flowing from the CAN bus 10 is stored in each channel for each frame according to the content of the message M0. For example, the content (X) frame is stored in channel 1 (ch1), and the other content (Y) and content (Z) frames are stored in ch2 and ch3.

  Here, it is possible to store the contents of a plurality of frames in one channel. However, if multiple frames transmitted at high speed are stored in one channel, the next content will be entered while trying to extract the content of the first entered frame, and as a result, the first content entered. The content of the frame may be overwritten with the next frame.

  Therefore, control is performed so that only one frame content is stored in one channel, that is, a dedicated message box. In other words, if the dedicated message box ch1 stores the content (X), it is set as the dedicated message box for the content (X). The contents (Y) and the like are stored in ch2 and the like, which are dedicated message boxes for the contents (Y).

  In this state, if ch3 which is a dedicated message box for content (Z) is fixed, there is an empty message box, so that the empty message box is newly used as a dedicated message box for content (Z). The acceptance mask is set to the next, and the next is to use this new dedicated message box.

  Note that, as described above, the timing for performing the sticking check to determine whether or not the dedicated message box is stuck is when it is determined that communication is to be started. This sticking check is performed based on whether or not the written value can be read after writing a predetermined value.

  Further, there is no need to search for an empty message box, and information on the empty message box is stored in advance and is updated afterwards. In other words, when the software is first created, for example, “content (X) is ch1”, “content (Y) is ch2”, “content (Z) etc. is ch3 etc.” Settings are made in advance such that message boxes other than are empty.

  Therefore, there is no need to search for an empty message box, and communication processing can be performed at high speed. In this case, the priority of adopting free mailboxes is not very important.

  As a result of the sticking check, if ch1 is enabled (E), ch2 is enabled (E), and ch3 is in a stuck state, ch3 is disabled (E) from disabled (E). Rewrite to D). In addition, the vacant channel is rewritten from disable (D) to enable (E).

  FIG. 8 is an explanatory diagram illustrating message reception timing in the first embodiment. A vehicle speed signal, an engine speed signal, an engine stop signal, various operation signals, various sensing signals, and various alarm signals are transmitted to the meter ECU 1 via the multiplex communication line 400 (FIG. 2). In FIG. 8, it is assumed that the signal is transmitted by the first message M1 and the second message M2 as an example.

  In FIG. 8, the first message M1 and the second message M2 are received at asynchronous timings. Therefore, between the first message M1 and the first message M1 at the time of reception, the second message M2 and the second message M2 are received. Even if there is a sufficient time TL, the time TS between the first message M1 and the second message M2 may be close to 0 seconds.

  Therefore, in receiving, in order to increase the communication speed, it is necessary to use different message boxes for the first message M1 of one frame and the second message M2 of one frame. That is, it is necessary to assign one dedicated message box to one ID.

  If the present invention is applied to communication using CAN in the meter ECU 1 in the instrument panel provided with the vehicle information providing apparatus 100 as in the first embodiment, the following effects can be obtained. . The meter ECU 1 has to execute many processes at a high speed while not using a high-class microcomputer.

  As in the present invention, if one dedicated message box is assigned to one frame and an alternative dedicated message box is assigned when sticking occurs, a large amount of data can be received at high speed without error, and the received data is garbled. Or correct reception of the vehicle information to the driver at high speed, leading to safe driving.

(Other embodiments)
The present invention is not limited to the above-described embodiments, and can be modified or expanded as follows. For example, in the first embodiment described above, an example in which a dedicated message box is used for reception has been described. However, even when a dedicated message box is used for transmission, the concept of the present invention is adopted. Can do.

  That is, when sticking occurs in the dedicated message box used for transmission, it can be replaced with an empty message box. Of course, the idea of the present invention can be adopted both at the time of transmission and at the time of reception.

  However, in the control of the vehicle information providing apparatus including the instrument and the display provided on the instrument panel of the vehicle, it is more effective to apply the present invention to the receiving side. The reason is that the vehicle information providing apparatus can display the situation in the vehicle without delay.

  As described with reference to FIG. 8, the first message M1 and the second message M2 are transmitted to the meter ECU 1 via the multiplex communication line 400. The time TS between the first message M1 and the second message M2 at the time of reception may be almost 0 seconds.

  Therefore, in reception, different dedicated message boxes must be used for the first message M1 of one frame and the second message M2 of one frame. That is, it is necessary to assign one dedicated message box to one ID.

  On the other hand, at the time of transmission, since it is rarely transmitted at random and is often transmitted in time series, it is almost always necessary to prepare one empty message box in one dedicated message box for transmission. is there. Note that the sticking check is also required at the time of transmission. If a dedicated message box that is stuck is used, data is sent in a garbled state.

  In addition, CAN is one of the ISO standard protocols for vehicle communication networks, and is a standard that is designed in consideration of enhanced noise resistance and used for data transfer between interconnected devices. It is widely used for transferring control information of equipment, and is also used in the field of robots such as transport machines, factories, and machine tools.

  Therefore, the present invention can be applied to these fields other than vehicles. In particular, the present invention is maximally effective when applied to the reception of data such as a transport machine information providing device, a factory monitoring information providing device, and a machine tool information providing device.

1 Electronic control unit for meter (ECU for meter) (electronic control unit)
2 Microcomputer
3 CAN controller having a plurality of message boxes 4 CAN transceiver for transmitting / receiving via CAN bus 5 Message box (aggregate)
6 Transmission control unit that frames messages and transmits them to CAN bus 7 Reception control unit that receives frames and extracts messages 8 CAN protocol control unit that performs arbitration control, error detection, and communication control 10 CAN Bus 20 Alarm display device (indicator)
26 Storage means for storing information of empty message box in advance 30, 40, 50 Each pointer-type display unit 100 Vehicle information providing device 200 Vehicle information terminal 210 Multiplex communication input / output terminal 230 Vehicle interface (vehicle I / F) means 250 control means 270 control output means 290 auditory information providing means 400 multiplex communication line 410 travel control device as another electronic control unit in the vehicle 420 operation means comprising various operation switches, etc. Ch1, ch2, ch3 dedicated message box (D) Disabled (disabled)
D1, D2 First and second display means (display unit)
(E) Enable (valid)
M0 Message that is the communication content for each frame M1 First message M2 Second message S402 Means for checking sticking of dedicated message box at the previous stage of communication S403 Means for using empty message box as alternative message box T1 First transition State T2 Second transition state T3 Third transition state T4 Fourth transition state (X), (Y), (Z) Contents

Claims (13)

Information is displayed on a multiplex communication line that divides the contents received for each frame and performs multiplex communication, and an information providing device that displays the status of devices connected to the multiplex communication line, and is connected to the multiplex communication line. An electronic control unit,
The electronic control device has a dedicated message box composed of a plurality of registers each of which is assigned a plurality of messages for each frame, which is the content of communication from the transmission side to the reception side, and stores data of the assigned messages. ,
An empty message box consisting of a register to which the message that is the content of the communication for each frame is not assigned;
A sticking check means for performing a sticking check as to whether or not the data contained in the dedicated message box is stuck before performing the communication;
As a result of the sticking check by the sticking check means, if it is determined that the data in the dedicated message box is stuck, setting means for setting the empty message box as an alternative message box for the dedicated message box to which the data is stuck And a multiplex communication apparatus.   In the electronic control device, among the plurality of messages, the first message and the second message to which the different dedicated message boxes are respectively assigned are asynchronous timings at which the transmission side and the reception side are not synchronized. 2. The multiplex communication apparatus according to claim 1, wherein   The electronic control device includes a meter electronic control unit that controls the vehicle information providing device that constitutes the information providing device, and displays the status of the vehicle including operation information of the device and operation information of the device in the vehicle. 3. The multiplex communication apparatus according to claim 1, wherein the information is displayed on the vehicle information providing apparatus in a vehicle.   The electronic control device includes a transport machine information providing device for displaying the status of the transport machine, a factory monitoring information providing device for displaying the status of the device in the factory, and a machine tool information providing for displaying the status of the machine tool. The multiplex communication apparatus according to claim 1, comprising an electronic control unit for any one of the apparatuses.   The electronic control unit has storage means for storing in advance the position information of the register serving as the empty message box, and the storage means stores the empty message box in the dedicated area where the data is stuck. 5. The multiplex communication apparatus according to claim 1, wherein the position information is updated each time the setting unit sets the message box as the alternative message box. 6. In the electronic control unit, an individual receiving mask corresponding to each frame is set,
The electronic control unit accommodates the message data of each corresponding frame in the dedicated message box according to the acceptance mask assigned to the dedicated message box,
Let the sticking check means check the inside of the register which becomes each dedicated message box in turn,
As a result of the sticking check, if it is determined that there is the register of the dedicated message box to which the data is stuck, the acceptance mask for the dedicated message box related to the register in which the sticking has occurred is set to the empty message box. Set
The determination according to claim 1, wherein if it is determined that there is no dedicated message box to which the data is fixed, the acceptance mask is set for the predetermined dedicated message box. Multiple communication device.   When the electronic control unit sets all the empty message boxes as the alternative message box of the dedicated message box, the electronic control unit can detect the empty message box before the dedicated message box to which the data is fixed is found. 7. The multiplex communication apparatus according to claim 1, wherein a warning display signal indicating that there is no signal is generated.   The electronic control device has no empty message box when the data relating to the dedicated message box is newly fixed when all the empty message boxes are replaced with the dedicated message box. 7. A multiplex communication apparatus according to claim 1, wherein a warning display signal is issued. In the electronic control unit connected to the multiplex communication line that divides the content received for each frame and performs multiplex communication by causing the information providing device to display the status of the device to divide the contents received for each frame, from the transmitting side to the receiving side for each frame A plurality of empty message boxes serving as alternatives are preliminarily assigned to a dedicated message box composed of a plurality of registers for storing data of the assigned messages. Set it,
A sticking check is performed to determine whether the data contained in the dedicated message box is not stuck. When the data is stuck, the data sticking occurs in one of a plurality of empty message boxes serving as the alternative means. A multiplex communication method, characterized in that it is set as an alternative message box for the dedicated message box. The electronic control device has a microcomputer in the electronic control device, and when the microcomputer is turned on, the microcomputer enters a first transition state, and initialization processing is performed in the first transition state. In the initialization process, the sticking check is performed,
When the initialization process is completed, the microcomputer enters the second transition state, which is the normal communication state. In the second transition state, when the communication is not necessary, the microcomputer Transition to the bus sleep state,
In the third transition state, when an operation is performed on the device connected to the electronic control unit via the multiplex communication line, the microcomputer returns to the first transition state,
10. The multiplex communication method according to claim 9, wherein, when the microcomputer sleeps in the third transition state, the microcomputer transitions to a fourth transition state and enters a sleep state. A separate receiving mask corresponding to each frame is set in the electronic control unit;
The dedicated message box accommodates message data of each frame corresponding to the dedicated message box according to the acceptance mask assigned to the dedicated message box,
The sticking check sequentially checks the inside of the register which becomes each dedicated message box, and if it is determined that there is the register of the dedicated message box to which the data sticks as a result of the sticking check, the sticking is checked. Setting the acceptance mask for the dedicated message box relating to the generated register for the empty message box;
The multiplex communication according to claim 9 or 10, wherein when it is determined that there is no dedicated message box to which the data is fixed, the acceptance mask is set for the predetermined dedicated message box. Method.   After setting all the empty message boxes as the alternative message box of the dedicated message box, before the dedicated message box to which the data is fixed is found, a warning display indicating that there is no empty message box The multiplex communication method according to claim 9, wherein the electronic control device emits a signal.   After all the empty message boxes are replaced with the dedicated message box, when the data relating to the dedicated message box is newly fixed, a warning display signal indicating that there is no empty message box is displayed. The multiplex communication method according to any one of claims 9 to 11, wherein the electronic control device emits.

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