JP4889411B2 - In-vehicle device communication system and distribution device - Google Patents

Description

  The present invention provides a vehicle-mounted device communication system comprising a plurality of vehicle-mounted devices and a distribution device that is connected to the vehicle-mounted device via an in-vehicle communication line and distributes data received from the vehicle-mounted device to the other vehicle-mounted devices, and the vehicle-mounted device communication. The present invention relates to a distribution device used in a system, and more particularly to an in-vehicle device communication system capable of suppressing the amount of data transmitted and received between the distribution device and the in-vehicle device and a distribution device used in the in-vehicle device communication system.

  2. Description of the Related Art In recent years, the number and types of electronic control units (ECUs) that electrically control onboard equipment or driving assistance functions tend to increase with the increase in equipment mounted on automobiles and the increase in driving assistance functions. .

  Accordingly, as the number of ECUs increases, the amount of data transmitted / received via an in-vehicle communication line to which the ECUs are connected also increases. The in-vehicle communication line is generally configured by connecting an ECU in a bus form to a serial bus conforming to CAN (Controller Area Network) or the like. For this reason, data used only by some ECUs is also transmitted to all ECUs connected to the same in-vehicle communication line. Therefore, an increase in the amount of data transmitted / received through the in-vehicle communication line causes data delay or loss due to collision (collision). A significant delay or loss of data may be fatal to driving assistance functions such as brake control by the ECU.

  Therefore, a configuration in which the in-vehicle communication line is divided into a plurality and ECUs are connected to different in-vehicle communication lines is generally used. This is because the waste of use of the in-vehicle communication line can be suppressed by collecting ECUs that commonly use data. There is also a configuration in which the ECUs are connected by being classified according to the type of data transmitted / received to / from the in-vehicle communication line having a different communication speed in order to efficiently use the in-vehicle communication line against the increase in the type of ECU. In these configurations, different in-vehicle communication lines are connected by a gateway device that controls transmission and reception of data. In this case, the gateway device functions as a distribution device that temporarily stores the data received from the ECU and distributes and transmits the stored data to the in-vehicle device that requires the data.

In Patent Document 1, priority information for identifying priority is added to data to be transmitted and received, and when the gateway device transmits and receives data between different in-vehicle communication lines, the priority is determined from the priority information of the received data. A technique is disclosed in which data having a high priority is preferentially transmitted so that transmission of data having a high priority is not greatly delayed even when the communication load of the in-vehicle communication line increases.
JP 2005-159568 A

  However, in the in-vehicle device communication system so far, when each in-vehicle device needs certain data, the gateway device functions as another distributor or another data for obtaining the data by processing such as calculation, determination, etc. Get from. Therefore, even if one data is necessary, a plurality of data are transmitted from the gateway device to the in-vehicle device. Therefore, the amount of data transmitted from the gateway device to the in-vehicle device increases.

  In patent document 1, when communication load is high, it aims at transmitting high priority data preferentially and not delaying greatly, and does not suppress an increase in the amount of data transmitted and received in the in-vehicle device communication system. .

  The present invention has been made in view of such circumstances, and reduces the amount of data transmitted to the in-vehicle device, reduces the communication load of the in-vehicle communication line, and further reduces the calculation load of the in-vehicle device. The main object is to provide a system and a distribution device used in the in-vehicle device communication system.

  Another object of the present invention is to provide an in-vehicle device communication system in which system update such as program change is easy.

A vehicle-mounted device communication system according to a first aspect of the present invention includes a plurality of vehicle-mounted devices having means for transmitting data and a data transmission request, and the vehicle-mounted device is connected to the vehicle-mounted device via an in-vehicle communication line and is received from one vehicle-mounted device. A distribution device for distributing the received data to other in-vehicle devices, the distribution device storing data received from one in-vehicle device, and from the storage means based on a transmission request received from the in-vehicle device In a vehicle-mounted device communication system including a transmission unit that reads and transmits data, one vehicle-mounted device includes a unit that transmits information indicating data to be acquired as a transmission request , and the distribution device calculates data to be transmitted. or other data necessary for determining and means for storing definition information that is to define the method of calculating or determining the data, when receiving the transmission request, Means for reading the other data required to calculate or determine the data shown in the transmission request based on the serial definition information from said storage means, said transmission request based on the read data and the definition information shown Means for calculating or determining the calculated data, and transmitting the calculated or determined data by the transmission means.

  The in-vehicle device communication system according to a second aspect is characterized in that the distribution device includes means for acquiring the definition information from the outside.

A distribution device according to a third aspect of the present invention comprises storage means for storing data received from the outside and transmission means for reading and transmitting data from the storage means based on the received transmission request, and distributes the data to the outside. In the distribution device, when receiving a transmission request, means for storing other data necessary for calculating or determining data to be transmitted, and definition information in which a method for calculating or determining the data is defined , It means for reading the other data required to calculate or determine the data shown in the transmission request based on the definition information from the storage unit, shown above to the transmission request based on the read data and the definition information provided and the means for calculating or determining the data, characterized in that the calculated or determined data are to be transmitted by said transmitting means.

  In the present invention, the distribution device is the acquisition target of the in-vehicle device based on the definition information stored in order to generate the data for the information indicating the acquisition target data transmitted as a transmission request from the in-vehicle device. Other data necessary for generating data is read, and data to be acquired by the in-vehicle device is generated based on the read data and definition information. The data transmitted from the distribution device to the in-vehicle device is data to be acquired by the in-vehicle device generated by the distribution device.

  In the present invention, definition information such as a function for generating data related to a transmission request from the in-vehicle device is acquired from the outside and stored in the distribution device.

  In the case of the present invention, the distribution device transmits necessary data to the data related to the transmission request, and the in-vehicle device does not generate and use the data based on the transmitted data, but the transmission from the in-vehicle device. The distribution device generates the data related to the request and transmits it. Therefore, it is possible to reduce the amount of data for transmitting other data necessary for generation processing such as calculation and determination of data related to the transmission request. Therefore, the load on the in-vehicle communication line of the in-vehicle device communication system can be reduced. Moreover, since a distribution apparatus performs a part or all of the arithmetic processing which the vehicle-mounted apparatus was performing, the process which a vehicle-mounted apparatus should perform can be simplified and the calculation load of a vehicle-mounted apparatus can be reduced.

  In the case of the present invention, the definition information for generating the data related to the transmission request from the in-vehicle device is acquired and stored from the outside, and the data related to the transmission request is generated based on the stored definition information. Even if it is necessary to change the definition information, it is not necessary to change every vehicle-mounted device, and only the distribution device may be changed. Therefore, the system update of the in-vehicle device communication system is easy.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.

  FIG. 1 is a schematic diagram showing the configuration of the in-vehicle device communication system of the present invention. The in-vehicle device communication system 1 includes at least on-vehicle devices 2a, 2b, 2c, 2d, 2e, 2f, and 2g using an electronic control unit (ECU), between the on-vehicle devices 2a, 2b, and 2c, between the on-vehicle devices 2d and 2e, In-vehicle communication lines 3a, 3b, 3c for connecting the in-vehicle devices 2f, 2g, distribution devices 4a, 4b, 4c connected to the in-vehicle communication lines 3a, 3b, 3c, and distribution devices 4a, 4b, 4c, respectively. Communication network 5 and sensors 6a and 6e connected to the in-vehicle devices 2a and 2e.

  The in-vehicle devices 2a, 2b, and 2c are connected to the in-vehicle communication line 3a in a bus type, and signals transmitted and received through the same in-vehicle communication line 3a are common to the in-vehicle devices 2a, 2b, and 2c connected to the in-vehicle communication line 3a. Can be received. The in-vehicle devices 2d, 2e, 2f, 2g connected to the other in-vehicle communication lines 3b, 3c are connected via the distribution devices 4a, 4b, 4c.

  The in-vehicle devices 2a, 2b, 2c, 2d, 2e, 2f, and 2g use electronic control devices, for example, transmission of measured values of various physical quantities detected by the sensors connected to the sensors, or control by microcomputers such as engines and brakes. It is a device that can. As a specific example, in the present embodiment, one in-vehicle device 2a functions as an ABS (Antilock Bracket System). The in-vehicle device 2a functioning as an ABS is connected to a sensor 6a that detects the rotation of the wheel. When the signal output from the sensor 6a at the time of braking indicates zero speed, the braking is automatically controlled to It is a device that prevents locking. In addition, the in-vehicle device 2a functioning as an ABS transmits information on the wheel speed detected via the sensor 6a to the other in-vehicle devices 2b, 2c and the distribution device 4a, and the other in-vehicle devices 2b, 2c, 2d, 2e, 2f and 2g can use wheel speed information. Further, the in-vehicle device 2e is connected to a sensor 6e that detects the tire angle, and transmits information on the tire angle detected through the sensor 6e to the other in-vehicle device 2d and the distribution device 4b. 2b, 2c, 2d, 2f, and 2g can use tire angle information.

  The in-vehicle communication lines 3a, 3b, and 3c are communication lines based on a CAN (Control Area Network) protocol. The in-vehicle devices 2a, 2b, and 2c are connected to the in-vehicle communication lines 3a, and the in-vehicle devices 2d and 2e are in-vehicle communication lines. The in-vehicle devices 2f and 2g can send and receive signals based on CAN via the in-vehicle communication line 3c via 3b. In the present embodiment, a communication line based on CAN will be described as an example of the in-vehicle communication lines 3a, 3b, 3c. However, the in-vehicle communication lines 3a, 3b, 3c used in the in-vehicle device communication system of the present invention are not limited to this, and signals may be transmitted / received based on a protocol such as LIN (Local Interconnect Network), FlexRay or the like. Furthermore, you may comprise in-vehicle communication line 3a, 3b, 3c from which the speed of data transmission / reception differs according to the kind of data transmitted / received.

  The in-vehicle communication lines 3a, 3b and 3c based on CAN are composed of two signal lines and detect a differential voltage generated between the signal lines as a signal level. The two signal lines are set to a potential of CAN_H level and CAN_L level, respectively. The state where there is no differential voltage between the two signal lines is “1” of the digital signal, and the state where there is a differential voltage is “ 0 ”. The in-vehicle devices 2a, 2b, 2c, 2d, 2e, 2f, and 2g connected to the in-vehicle communication lines 3a, 3b, and 3c generate signals by generating a differential voltage between the signal lines of the in-vehicle communication lines 3a, 3b, and 3c. Can be sent.

  The distribution device 4a receives data by detecting data signals (data frames) from the in-vehicle devices 2a, 2b, 2c connected to the in-vehicle communication line 3a to be connected, and a transmission request signal from the in-vehicle devices 2a, 2b, 2c. A data signal is transmitted according to (remote frame). Similarly, the distribution device 4b can transmit and receive transmission request signals and data signals based on CAN with the in-vehicle devices 2d and 2e connected to the in-vehicle communication line 3b, and the distribution device 4c is connected to the in-vehicle communication line 3c. Transmission request signals and data signals based on 2g and CAN can be transmitted and received.

  The distribution devices 4a, 4b, and 4c are connected by a communication network 5, and the distribution devices 4a, 4b, and 4c can transmit and receive data to and from each other. In the present embodiment, an example in which the communication network 5 is configured by a packet switching network is shown. However, the communication network 5 that connects the distribution devices 4a, 4b, and 4c in the in-vehicle device communication system of the present invention is not limited to this as long as data can be transmitted and received between the distribution devices 4a, 4b, and 4c. A line may be used. The distribution device 4a can be connected to the central device 10 installed outside by wireless communication. In the present embodiment, only the distribution device 4a can be connected to the central device 10. However, the present invention is not limited to this, and any of the distribution devices 4a, 4b, and 4c may be connected to the central device 10 by wireless communication.

  FIG. 2 is a block diagram showing the internal configuration of the in-vehicle device 2a and the distribution device 4a constituting the in-vehicle device communication system 1 of the present invention. The in-vehicle device 2a includes at least a control unit 20, a power source 21, a storage unit 22, a communication control unit 23, an input unit 24, and an output unit 25. Since the other vehicle-mounted devices 2b, 2c, 2d, 2e, 2f, and 2g have the same configuration as the vehicle-mounted device 2a, detailed description thereof is omitted. Depending on the in-vehicle device, only one of the input unit 24 and the output unit 25 may be provided.

  The control unit 20 of the in-vehicle device 2a receives the supply of power from the power source 21, detects a signal from the sensor 6a connected to the in-vehicle device 2a via the input unit 24, and sends the signal to the in-vehicle device 2a via the output unit 25. A control signal is transmitted to a device to be controlled to be connected. Moreover, the control part 20 of the vehicle equipment 2a memorize | stores in the memory | storage part 22 the various information which generate | occur | produces in the process.

  The communication control unit 23 has a network controller chip and realizes communication with the in-vehicle communication line 3a. The control unit 20 generates a differential voltage between the signal lines of the in-vehicle communication line 3a as described above via the communication control unit 23, and transmits a signal represented by “0” and “1”. The signal is received by detecting the differential voltage. The control unit 20 of the in-vehicle device 2a detects a signal from the sensor 6a with a constant time of, for example, 10 milliseconds by the input unit 24, and transmits a data signal including data indicated by the detected signal by the communication control unit 23.

  Moreover, the control part 20 of the vehicle equipment 2a produces | generates a transmission request signal in order to request | require transmission of various information to the distribution apparatus 4a. For example, in CAN, it is specified that the signal transmitted from the in-vehicle device 2a to the distribution device 4a and the other in-vehicle devices 2b and 2c includes information for identifying whether it is a transmission request signal or a data signal. In CAN, an ID (Identifier) is assigned for each type of information such as wheel speed (front right / front left / rear right / rear left), engine speed, and wheel angle. For example, when the information on the engine speed is required for the control of the in-vehicle device 2a, the signal generated by the control unit 20 of the in-vehicle device 2a is information identifying the transmission request signal and the ID assigned to the engine speed. Is represented.

  The distribution device 4a includes at least a CPU 40 for controlling the entire distribution device 4a, a RAM 41 composed of a volatile memory, a ROM 42 composed of a non-volatile memory, a first communication unit 43 connected to the in-vehicle communication line 3a, a communication network 5 and a third communication unit 45 for connecting to the central device 10 outside the in-vehicle device communication system 1. Since the other distribution devices 4b and 4c have the same configuration as the distribution device 4a, detailed description thereof is omitted.

  The ROM 42 stores a control program for operating as the distribution device 4a, and the CPU 40 operates as the distribution device 4a by reading this control program. In addition, the ROM 42 stores an ID and the like for each type of information based on CAN for identifying the type of data that the distribution device 4a transmits / receives to / from the in-vehicle devices 2a, 2b, and 2c.

  The CPU 40 stores various information included in the data signals received from the in-vehicle devices 2a, 2b, and 2c in a DB (Data Base) 411 of the RAM 41. The CPU 40 stores the ID of the information read from the received data signal in the DB 411 of the RAM 41 and the value of the information indicated by the ID in association with each other.

  Further, the RAM 41 or the ROM 42 stores definition information 46 such as other information types necessary for deriving the information for each type of information and functions calculated using the necessary information. Definition information 46 that is changed while the in-vehicle device communication system 1 is in operation is stored in the RAM 41, and invariant definition information 46 that is not changed is stored in the ROM 42. The CPU 40 of the distribution device 4a can acquire the definition information from the central device 10 installed outside the in-vehicle device communication system 1 via the third communication unit 45. The CPU 40 calculates information related to the transmission request signal by reading the definition information 46 stored in the RAM 41 or the ROM 42.

  The RAM 41 temporarily stores various information generated during the process of the CPU 40.

  The CPU 40 receives data signals and transmission request signals from the in-vehicle devices 2a, 2b, 2c connected to the in-vehicle communication line 3a via the first communication unit 43. The CPU 40 transmits and receives various information to and from other distribution devices 4b and 4c connected to the communication network 5 via the second communication unit 44. Further, the CPU 40 transmits the definition information 46 acquired from the central apparatus 10 and stored in the RAM 41 or the ROM 42 to the other distribution apparatuses 4b and 4c. The distribution devices 4b and 4c can also store the definition information 46 in the RAM 41 or the ROM 42 and read the definition information 46.

  The CPU 40 of the distribution device 4a transmits a value for the information stored in the DB 411 of the RAM 41 to the other distribution devices 4b and 4c via the second communication unit 44, for example, every 10 milliseconds. Similarly, the distribution device 4b stores the value of information obtained by receiving the data signals from the in-vehicle devices 2d and 2e, and transmits them to the distribution devices 4a and 4c at regular intervals. , 2g, the information value obtained by receiving the data signal is stored and transmitted to the distribution devices 4a and 4b at regular intervals. Accordingly, the distribution devices 4a, 4b, and 4c can store the latest values of various information in the DB 411 of the RAM 41 in synchronization.

  In the in-vehicle device communication system 1 configured as described above, a process for obtaining information necessary for control by one in-vehicle device 2f will be described as a specific example. The internal configuration of the in-vehicle device 2f and the internal configuration of the distribution device 4c connected to the in-vehicle device 2f via the in-vehicle communication line 3c are the same as the internal configuration of the in-vehicle device 2a and the internal configuration of the distribution device 4a, respectively. Will be described.

  One vehicle-mounted device 2f is a device that controls the handle angle to assist driving. The vehicle-mounted device 2f needs to acquire information on wheel speed and tire angle when determining the handle angle for the control. The in-vehicle device 2f transmits a transmission request signal to the distribution device 4c in order to acquire information on the wheel speed and the tire angle, and a data signal describing the information on the wheel speed and the tire angle is transmitted from the distribution device 4c. Thus, the in-vehicle device 2f can also acquire necessary information.

  However, the in-vehicle device 2f constituting the in-vehicle device communication system 1 of the present invention does not need to transmit a transmission request signal related to each information in order to acquire information on wheel speed and tire angle. The distribution device 4c constituting the in-vehicle device communication system 1 of the present invention receives the wheel speed information from the distribution device 4a that has received the data signal from the in-vehicle device 2a connected to the sensor 6a that detects the wheel speed, and receives the DB 411 of the RAM 41. I remember it. Similarly, the distribution device 4c receives tire angle information from the distribution device 4b that has received the data signal from the in-vehicle device 2e connected to the sensor 6e that detects the tire angle, and stores the information in the DB 411 of the RAM 41. The distribution device 4c further stores, in the RAM 41 or the ROM 42, definition information 46 including a function for calculating or determining the steering wheel angle from the tire angle information and the wheel speed information. Therefore, the CPU 40 of the distribution device 4 c can determine the value of the handle angle based on the definition information 46. Therefore, the control unit 20 of the in-vehicle device 2f transmits the transmission request signal related to the steering wheel angle necessary for control, and acquires the steering wheel angle information directly from the distribution device 4c without acquiring the wheel speed and tire angle information. can do.

  FIG. 3 is an explanatory diagram illustrating an example of the definition information 46 stored in the RAM 41 or the ROM 42 of the distribution devices 4a, 4b, and 4c constituting the in-vehicle device communication system 1 according to the embodiment of the present invention. In the example of the definition information 46 illustrated in FIG. 3, a function for calculating or determining various types of information for various information IDs is stored. For example, in order for the in-vehicle device 2f to calculate the steering wheel angle necessary for the control, information on the tire angle and the wheel speed is necessary, and it can be calculated by the function f1. Similarly, in order to determine the injection amount of the engine, information such as the engine speed and the intake air pressure is necessary, and it can be determined by the function f2. In order to determine the temperature of the air blown out from the air conditioner, information such as the outside air temperature, the inside air temperature, and the amount of solar radiation is necessary, and it can be determined by the function f3. The distribution device 4c can read the definition information 46 stored in the RAM 41 or the ROM 42, calculate a handle angle value related to the transmission request signal, and generate a data signal indicating the handle angle.

  FIG. 4 is a flowchart showing a processing procedure when distribution device 4c constituting in-vehicle device communication system 1 according to the embodiment of the present invention receives a transmission request signal from in-vehicle device 2f.

  CPU40 receives a signal via the 1st communication part 43 (step S101), and judges whether the received signal is a data signal (step S102). If the CPU 40 determines that the received signal is a data signal (S102: YES), the CPU 40 reads the ID indicating the type of information from the received data signal (step S103), and further reads the value of the information from the data signal (step S103). Step S104). The CPU 40 associates the ID and value of the read information with each other and stores them in the DB 411 of the RAM 41 (step S105) and ends the process.

  When it is determined that the signal received by the CPU 40 is not a data signal (S102: NO), the signal received by the CPU 40 is a transmission request signal. Therefore, the CPU 40 reads an ID indicating the type of information from the transmission request signal (step S106) and temporarily stores it in the RAM 41 (step S107).

  The CPU 40 reads definition information 46 for calculating or determining information indicated by the read ID from the RAM 41 or the ROM 42 (step S108), and calculates or determines information related to the request based on the read definition information 46. The value of other necessary information is read from the DB 411 of the RAM 41 (step S109). The CPU 40 calculates or determines the value of the information related to the request based on the read information value and the read definition information 46 (step S110). CPU40 produces | generates the data signal containing the information of the calculated or determined result (step S111), and transmits it via the 1st communication part 43 to the vehicle-mounted apparatus 2f connected to the in-vehicle communication line 3c (step S112).

  Up to now, the information necessary for the in-vehicle device 2f is the steering wheel angle, and the information on the wheel speed and the tire angle necessary for determining or calculating the steering wheel angle is the in-vehicle communication line to which the in-vehicle device 2f is connected. It was sent to 3c. In the in-vehicle device communication system 1 of the present invention, only the handle angle information, which is necessary information for the in-vehicle device 2f, is sent from the distribution device 4c to the in-vehicle communication line 3c by the processing as described above. Therefore, it is possible to reduce the amount of data transmitted / received through the in-vehicle communication line 3c. Further, since the control unit 20 of the in-vehicle device 2f does not calculate or determine the steering wheel angle, but the CPU 40 of the distribution device 4c calculates or determines the calculation processing of the in-vehicle device 2f is reduced, and the load is reduced. These effects are the same in the other distribution devices 4a and 4b and in-vehicle devices 2a, 2b, 2c, 2d, 2e, and 2g. Therefore, the amount of data transmitted / received via the in-vehicle communication lines 3a, 3b, 3c constituting the in-vehicle device communication system 1 is reduced, and the control unit 20 of the in-vehicle devices 2a, 2b, 2c, 2d, 2e, 2f, 2g is simple. It can be configured.

  Next, a process for replacing the definition information 46 stored in the RAM 41 or ROM 42 of the distribution device 4a with new definition information will be described. FIG. 5 is a flowchart showing a processing procedure in which the distribution device 4a constituting the in-vehicle device communication system 1 according to the embodiment of the present invention acquires definition information from the external central device 10.

  CPU40 judges whether it is connectable with the central apparatus 10 installed out of the vehicle-mounted apparatus communication system 1 via the 3rd communication part 45 (step S21). When it is determined that the CPU 40 cannot be connected to the central device 10 (S21: NO), the CPU 40 returns the process to step S21 and determines that it can be connected to the central device 10 installed outside the in-vehicle device communication system 1. Wait until.

  When it is determined that the CPU 40 can be connected to the central apparatus 10 (S21: YES), the CPU 40 acquires definition information from a storage unit (not shown) of the central apparatus 10 (step S22), and stores the acquired definition information in the RAM 41. (Step S23).

  Thereby, for example, when there is an error in the definition information 46 stored in the RAM 41 of the distribution device 4a constituting the in-vehicle device communication system 1, it is necessary to modify the definition information 46 such as when the definition information 46 is updated. In addition, the definition information can be acquired from the outside, and the in-vehicle device communication system 1 can be easily updated.

  The CPU 40 of the distribution device 4a reads update information such as version information between the definition information read from the central device 10 and the definition information 46 stored in the RAM 41 or ROM 42, and the definition information read from the central device 10. If the version information is new, the definition information may be acquired and stored in the RAM 41.

  Moreover, in this Embodiment, it was set as the structure which CPU40 of the distribution apparatus 4a acquires definition information from the central apparatus 10 installed in the exterior of the vehicle-mounted apparatus communication system 1 via the 3rd communication part 45. FIG. The in-vehicle device communication system 1 of the present invention is not limited to this, and includes an auxiliary storage device capable of reading a portable storage medium such as a CD-ROM, a DVD-ROM, a flash memory, a portable HDD (Hard Disk Drive) or the like. It is also possible to acquire definition information from a portable storage medium. In this embodiment, a configuration is provided that includes means for acquiring definition information from the outside. However, the present invention is not limited to this, and it is needless to say that the data related to the transmission request signal may be calculated or determined based on the definition information stored in advance in the distribution device without acquiring the definition information from the outside.

  In the present embodiment, the configuration as shown in FIG. 1 has been described as an example. However, it goes without saying that the number of in-vehicle devices, distribution devices, in-vehicle communication lines, and the like are not limited.

It is a schematic diagram which shows the structure of the vehicle-mounted apparatus communication system of this invention. It is a block diagram which shows the internal structure of the vehicle equipment and distribution device which comprise the vehicle equipment communication system of this invention. It is explanatory drawing which shows the example of the definition information memorize | stored in RAM or ROM of the distribution apparatus which comprises the vehicle-mounted apparatus communication system in embodiment of this invention. It is a flowchart which shows the process sequence when the distribution apparatus which comprises the vehicle-mounted apparatus communication system in embodiment of this invention receives the transmission request signal from a vehicle-mounted apparatus. It is a flowchart which shows the process sequence in which the distribution apparatus which comprises the vehicle-mounted apparatus communication system in embodiment of this invention acquires definition information from an external central apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 In-vehicle apparatus communication system 2a, 2b, 2c, 2d, 2e, 2f, 2g In-vehicle apparatus 20 Control part 23 Communication control part 3a, 3b, 3c In-vehicle communication line 4a, 4b, 4c Distribution apparatus 40 CPU
41 RAM
411 DB
42 ROM
46 Definition Information 5 Communication Network

Claims (3)

Distribution that distributes data received from one in-vehicle device to other in-vehicle devices, and a plurality of in-vehicle devices having means for transmitting data and a data transmission request, connected to the in-vehicle device via an in-vehicle communication line The distribution device includes storage means for storing data received from one in-vehicle device, and transmission means for reading and transmitting data from the storage means based on a transmission request received from the in-vehicle device. In the in-vehicle device communication system,
One in-vehicle device
Comprising means for transmitting information indicating acquisition target data as a transmission request ;
The distributor is
Means for storing other data necessary for calculating or determining data to be transmitted, and definition information defining a method for calculating or determining the data ;
When receiving the transmission request, and means for reading the other data required to calculate or determine the data shown in the transmission request based on the definition information from said storage means,
Means for calculating or determining the data indicated in the transmission request based on the read data and the definition information;
An in-vehicle device communication system, wherein the calculated or determined data is transmitted by the transmission means. The in-vehicle device communication system according to claim 1, wherein the distribution device includes means for acquiring the definition information from the outside. In a distribution device for distributing data to the outside, comprising storage means for storing data received from outside, and transmission means for reading and transmitting data from the storage means based on the received transmission request,
Means for storing other data necessary for calculating or determining data to be transmitted, and definition information in which a method for calculating or determining the data is defined;
When receiving the transmission request, and means for reading the other data required to calculate or determine the data shown in the transmission request based on the definition information from said storage means,
Means for calculating or determining the data indicated in the transmission request based on the read data and the definition information;
The distribution device, wherein the calculated or determined data is transmitted by the transmission means.

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