JP5030614B2 - In-vehicle communication system and in-vehicle communication method - Google Patents

Description

  The present invention relates to an in-vehicle communication system in which ECUs (Electronic Control Units) are divided into a plurality of groups and connected to an in-vehicle communication line for each group, and in particular, data transmitted from each ECU is recorded and also to each ECU. Data obtained by each ECU from the in-vehicle communication device for each group when a plurality of in-vehicle communication devices having a database for transmitting data are provided for each group and the in-vehicle communication devices for each group are connected by a trunk line. ECUs that use data whose real-time nature is important are read from the recording area where the data is updated to the latest contents. The present invention relates to an in-vehicle communication system and an in-vehicle communication method that can use the recorded data.

  In recent years, the number and types of ECUs that electrically control mounted devices or driving assistance functions tend to increase with the increase in the number of devices 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. An increase in the amount of data transmitted and 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 ECUs are divided into a plurality of groups and the ECUs are connected to different in-vehicle communication lines for each group is common. Further, in order to efficiently use the in-vehicle communication line against the increase in the ECU, there is a configuration in which the ECU group is classified according to the type of data transmitted and received and connected to the in-vehicle communication line having a different communication speed for each group. In these configurations, different in-vehicle communication lines are connected by a gateway device that controls transmission and reception of data.

Patent Document 1 discloses a configuration in which ECUs are divided into a plurality of groups and connected to communication lines for each group, and in-vehicle communication lines are further connected by a gateway device, and the priority for identifying the priority order of transmitted / received data. When information is added and 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, and data with high priority is transmitted preferentially. A technique for preventing transmission of data with high priority from being greatly delayed even when the communication load increases is disclosed.
JP 2005-159568 A

  When the ECUs are divided into a plurality of groups and the ECUs are connected via the gateway device, the content of the data updated by the ECUs in one group is updated after the other group via the gateway device. There is a time zone in which the contents of data do not match between one group and the other group until it is transmitted to the ECU. Further, when a plurality of groups of ECUs are connected in series to the gateway device, there is a possibility that a time difference will occur in steps in the data contents between one group and another group.

  In other words, even though data with the same contents should originally be usable in each ECU, data consistency between different groups is achieved by dividing each ECU into a plurality of groups in order to reduce the communication load. Will be lost. Therefore, even if the physical distance between the ECUs is long, it is necessary to connect to the same group when it is necessary to have the same contents with respect to the data of one attribute. Is required. In addition, when the same physical data is necessary for each control object even though the physical distance between the plurality of control objects is long, the control must be concentrated on one ECU. An extra long-distance communication line is required to connect to.

  The present invention has been made in view of such circumstances, and each group includes an in-vehicle communication device having a database for recording data transmitted from each in-vehicle device such as an ECU divided into a plurality of groups. Furthermore, while it is set as the structure which synchronizes a database with each vehicle-mounted communication apparatus, since the data which is the same content are not necessarily required by all the vehicle-mounted apparatuses, about the data updated to the newest content, each vehicle-mounted communication apparatus The recording is performed in the buffer provided in the above. As a result, the databases of each in-vehicle communication device are synchronized with the same content, and the content of the data that each in-vehicle device acquires from the in-vehicle communication device for each group is consistent with the data acquired in other groups. An in-vehicle communication system and an in-vehicle communication that can use data read from a buffer updated to the latest contents can be used for an in-vehicle apparatus that uses data whose real-time property is important. It aims to provide a method.

  Another object of the present invention is that when an in-vehicle communication device transmits a database to another in-vehicle communication device in order to synchronize the database, the in-vehicle communication device is recorded in a buffer provided for the database. By using a configuration in which only data transmitted from the device, that is, updated data is transmitted to other in-vehicle communication devices connected to other groups, the database included in each in-vehicle communication device is the same using the latest data. To provide an in-vehicle communication system and an in-vehicle communication method in which some in-vehicle devices can use data read from a buffer updated to the latest content. is there.

  Another object of the present invention is to specify that an in-vehicle device that uses data transmitted from an in-vehicle communication device transmits data read from a recording area of either a database or a buffer to the in-vehicle communication device. With the configuration, data read from a database having the same contents as other groups and data with high real-time properties that may not be the same contents as other groups but are updated are recorded. An object of the present invention is to provide an in-vehicle communication system and an in-vehicle communication method capable of selecting and using arbitrary data with data read from a buffer.

  Another object of the present invention is that the in-vehicle communication device stores either a database or a buffer as a recording area for reading out data to be transmitted for each in-vehicle device. There is a distinction between data read from a database that has the same content and data read from a buffer that contains data that may not have the same content as other groups but is updated and has high real-time properties. Another object is to provide an in-vehicle communication system and an in-vehicle communication method that can be used by each in-vehicle device.

An in-vehicle communication system according to a first aspect of the present invention is an in-vehicle communication system including a plurality of in-vehicle devices that transmit and receive data and an in-vehicle communication line that connects the in-vehicle devices divided into a plurality of groups for each group. Each in-vehicle communication device having a database for recording data transmitted / received to / from each in-vehicle device via the in-vehicle communication line and a buffer for the database. Is connected via a communication line different from the in-vehicle communication line, and the predetermined data of the data recorded in the database or the buffer is transferred to another in-vehicle communication device via the communication line. Means for transmitting, means for recording data transmitted from the other in-vehicle communication device via the communication line in the database, and via the in-vehicle communication line Means for recording data transmitted from a connected in-vehicle device in the buffer; and means for transmitting data read from the database or the buffer to the in-vehicle device connected via the in-vehicle communication line; It is characterized by providing.

  The in-vehicle communication system according to the second invention is characterized in that each of the in-vehicle communication devices transmits only the data recorded in the buffer as the predetermined data.

  In the in-vehicle communication system according to a third aspect of the invention, the in-vehicle device stores means for specifying designation information for specifying a recording area of either the database or the buffer, and means for transmitting the designation information to the in-vehicle communication device. The in-vehicle communication device includes: means for receiving designation information transmitted from the in-vehicle device; and data read from a recording area designated by the received designation information via the in-vehicle communication line. And means for transmitting via.

  In the in-vehicle communication system according to a fourth aspect of the invention, the in-vehicle communication device stores either the database or the recording region as a recording area for reading out data to be transmitted for each in-vehicle device. The data read from the stored recording area is transmitted.

Vehicle communication method according to the fifth invention includes a plurality of vehicle devices for sending and receiving data, and a vehicle in the communication line to connect the vehicle device which is divided into a plurality of groups for each respective group, further, each group A plurality of in-vehicle communication devices each having a database that records data to be transmitted / received to / from each in-vehicle device and a buffer for the database. , similar vehicle communication system are connected via a separate communication line and the communication line within the car with one another, the in-vehicle communication apparatus, the data transmitted from the in-vehicle device included in the first group of the other group met-vehicle communication method for transmitting to the in-vehicle device included, the vehicle communication device provided in the first group of some or all of the data transmitted through the communication line within the car from the car device, myself Was recorded in the buffer to records the data recorded in the buffer in its own database, the predetermined data among the data recorded in the database or the buffer to the in-vehicle communication device included in other groups The in- vehicle communication device that is transmitted through the communication line and is provided in the other group records the predetermined data transmitted from the in-vehicle communication device that is provided in the one group in its own database, The other group of in-vehicle communication devices reads data from the database or its own buffer and transmits the data to the in-vehicle device via the in-vehicle communication line .

  In the in-vehicle communication method according to a sixth aspect of the present invention, each of the in-vehicle communication devices transmits only the data recorded in the buffer as the predetermined data.

In the in-vehicle communication method according to a seventh aspect of the invention, the in-vehicle device transmits designation information for designating a recording area of either the database or the buffer to the in-vehicle communication device, and the in-vehicle communication device is transmitted from the in-vehicle device. receiving a designation information transmitted, and transmits the output data read from the recording area specified to the vehicle device by the received the designation information.

  In the in-vehicle communication method according to the eighth aspect of the invention, each in-vehicle communication device stores either the database or the recording region as a recording area for reading out data to be transmitted for each in-vehicle device, and stores the in-vehicle device for each in-vehicle device. Data read from the recording area is transmitted.

In the first invention and the fifth invention, in-vehicle communication systems having a configuration in which on-vehicle devices that transmit and receive data are divided into a plurality of groups and connected to the in-vehicle communication line for each group are connected to the in-vehicle communication line for each group. In addition, a vehicle-mounted communication device having a database for recording data transmitted from each vehicle-mounted device and a buffer for the database is further included. Each in-vehicle communication device is connected via a communication line different from the in-vehicle communication line connecting between the in-vehicle devices and between the in-vehicle device and the in-vehicle communication device. In order to synchronize the contents of the database from each in-vehicle communication device, predetermined data among the data recorded in the database or buffer is transmitted to the other in-vehicle communication device via the communication line, and Data transmitted from other in-vehicle communication devices is recorded in the database. Thereby, the data recorded by each in-vehicle communication device is exchanged, and the contents of the database of the in-vehicle communication device are synchronized with the same content. On the other hand, the buffer provided in the in-vehicle communication device records part or all of the data transmitted from the in-vehicle device connected via the in-vehicle communication line even during the processing for synchronization. The Further, data read from either the database or the buffer is transmitted to each in-vehicle device connected via the in-vehicle communication line.

  In the second and sixth inventions, when data for synchronizing the contents of the database is transmitted from the in-vehicle communication device to another in-vehicle communication device via the communication line, the data is transmitted from the in-vehicle device and recorded in the buffer. Only data is transmitted to other in-vehicle communication devices. The buffer is connected to the in-vehicle communication device via the in-vehicle communication line, separately from the database for securing the same contents for recording the data transmitted from the in-vehicle communication device connected to another group. Data transmitted from the in-vehicle device is recorded. In other words, the buffer in which the data transmitted from the in-vehicle device is recorded is used as a synchronization waiting buffer in which the difference due to the update is recorded before the synchronization of the database is completed.

  In the third and seventh inventions, the in-vehicle device specifies whether the data should be read from the recording area of the database or the buffer and transmitted to the in-vehicle communication device that records the data in both the database and the buffer. Is transmitted, data is read from the specified database or buffer and transmitted to the in-vehicle device.

  In the fourth and eighth inventions, in-vehicle communication devices that record data in both the database and the buffer, the data to be transmitted for each in-vehicle device connected via the in-vehicle communication line is stored in either the database or the buffer. Whether to read from the recording area is stored, and data read from the recording area stored for each on-vehicle device is transmitted.

  According to the first and fifth inventions, data synchronized with the same contents in different groups is recorded in the database of each in-vehicle communication device connected via a communication line. As a result, the database of each in-vehicle communication device is synchronized with the same content, and the content of data that each in-vehicle device acquires from the in-vehicle communication device for each group is consistent with the data acquired in other groups. Can have sex. On the other hand, data transmitted from the in-vehicle device to which the in-vehicle communication device is connected via the in-vehicle communication line is recorded in the buffer of each in-vehicle communication device. If the data transmitted from the in-vehicle device is the latest data updated by the in-vehicle device, data with high real-time characteristics is recorded in the buffer. Thereby, each in-vehicle device connected to each in-vehicle communication device via the in-vehicle communication line can use the data recorded in the database or the data recorded in the buffer as necessary.

  Therefore, in the in-vehicle communication system according to the present invention, when the in-vehicle devices are divided into a plurality of groups, it is important that the contents match the data used by the other in-vehicle devices connected to the other group. An in-vehicle device that uses simple data and an in-vehicle device that uses data in which real-time property is important can be connected to the same in-vehicle communication line and coexist in the same group.

  In the case of the second and sixth inventions, the data transmitted from the in-vehicle communication device to the other in-vehicle communication device via the communication line in order to synchronize the contents of the database is only the data read from the buffer. Data transmitted from each in-vehicle device newly connected to the in-vehicle communication device via the in-vehicle communication line after the database is synchronized. Therefore, since the difference by the update from the synchronized database is transmitted, the database included in each in-vehicle communication device can be synchronized with the same content using the latest data, and some in-vehicle devices are The data read from the buffer updated to the latest contents can be used. Furthermore, since the amount of data transmitted to the communication line by each in-vehicle communication device is only updated data recorded in the buffer, the communication load on the communication line connecting between the in-vehicle communication devices can be reduced.

  In the case of the third and seventh inventions, data is read from the recording area designated by the designation information transmitted from the in-vehicle device in the database or the buffer and transmitted to the in-vehicle device. Therefore, each in-vehicle device has data read from a database synchronized with the same content as the other group, and updated real-time data that may not be the same content as the other group. Arbitrary data can be designated and used with the data read from the recorded buffer.

  In the case of the fourth and eighth inventions, the data read from the recording area stored for each in-vehicle device in the in-vehicle communication device is transmitted to the in-vehicle device. Therefore, the data read from the database having the same contents as the other groups and the buffer that stores the updated real-time data that may not be the same contents as the other groups but are updated are read. It is possible to make each vehicle-mounted device use it separately from the recorded data.

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

(Embodiment 1)
FIG. 1 is a configuration diagram showing a configuration of an in-vehicle communication system according to the present invention. The in-vehicle communication system includes ECUs (Electronic Control Units) 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... that are in-vehicle devices divided into a plurality of groups. , 4c, 4c,..., 4d, 4d,..., 4d, 4d,..., And in-vehicle communication lines 3a, 3b, 3c. , 3d connected to the vehicle-mounted communication devices 1a, 1b, 1c, 1d and the communication lines 2 connecting the vehicle-mounted communication devices 1a, 1b, 1c, 1d to the communication line 2 serving as a trunk line. Connected between the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... divided into a plurality of groups via the connected vehicle-mounted communication devices 1a, 1b, 1c, 1d It constitutes a trunk type in-vehicle network.

  Each in-vehicle communication device 1a, 1b, 1c, 1d is connected to the communication line 2 respectively. The connection form (topology) may be any form such as a bus type, a star type, or a daisy chain type. Each of the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... and the in-vehicle communication devices 1a, 1b, 1c, 1d are connected to the respective in-vehicle communication lines 3a, 3b, 3c, 3d. Although connected, the connection form may be any form such as a bus type, a star type, or a daisy chain type.

  Each of the in-vehicle communication devices 1a, 1b, 1c, 1d is a communication device provided with a storage area used as the databases 11a, 11b, 11c, 11d. The in-vehicle communication device 1a basically records the data transmitted from the ECUs 4a, 4a... Connected to the in-vehicle communication line 3a in the database 11a, and transmits the data read from the database 11a to the ECUs 4a, 4a. .

  The communication line 2 is a cable such as a coaxial cable for connecting the in-vehicle communication devices 1a, 1b, 1c, and 1d, and a cable suitable for the connection form is used. The in-vehicle communication lines 3a, 3b, 3c, 3d connect the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... and the in-vehicle communication devices 1a, 1b, 1c, 1d. And a cable suitable for the connection form is used.

  The ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... transmit data including numerical information of various physical quantities such as measured values, calculated values, control values, or engines, brakes, etc. This is a device that can be controlled by a microcomputer. For example, one ECU 4a functions as an ABS (Antilock Break System) and is connected to a sensor (not shown) that detects the rotational speed (wheel speed) of the wheel. The one ECU 4a controls the brake based on the wheel speed detected via the sensor during braking of the vehicle, and transmits data including the measured value of the wheel speed to the in-vehicle communication device 1a.

  Here, when the wheel speed data transmitted from the ECU 4a is also used in each of the ECUs 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... connected to the other in-vehicle communication lines 3b, 3c, 3d. The in-vehicle communication device 1a records the wheel speed data in the databases 11b, 11c, and 11d of the other in-vehicle communication devices 1b, 1c, and 1d, and the in-vehicle communication devices 1b, 1c, and 1d are connected to the ECUs 4b, 4b,. 4c, 4c,..., 4d, 4d,. Therefore, each in-vehicle communication device 1a, 1b, 1c, 1d transmits data transmitted from each ECU 4a, 4a,..., 4b, 4b,..., 4c, 4c,. , 1b, 1c, 1d, received by each of the in-vehicle communication devices 1a, 1b, 1c, 1d, and recorded in the respective databases 11a, 11b, 11c, 11d.

  By the way, among the data recorded in the databases 11a, 11b, 11c, 11d, the data received simultaneously by the respective ECUs 4a, 4b, 4c, 4d connected to different in-vehicle communication lines 3a, 3b, 3c, 3d are the same. It may be desirable that The problem is that the contents of the respective databases 11a, 11b, 11c, and 11d are not synchronized with the same contents. For example, there may be a problem that the speed value included in the wheel speed data recorded in the database 11a is different from the speed value included in the wheel speed data recorded in the database 11b.

  Therefore, each of the in-vehicle communication devices 1a, 1b, 1c, and 1d constituting the in-vehicle communication system according to the present invention synchronizes the databases 11a, 11b, 11c, and 11d with the same contents. A process of sending and receiving and recording to exchange is executed. A white arrow in FIG. 1 represents a flow in which data is mutually exchanged by the in-vehicle communication devices 1a, 1b, 1c, and 1d.

  Each in-vehicle communication device 1a, 1b, 1c, 1d is connected to each other while executing processing for exchanging data recorded in the databases 11a, 11b, 11c, 11d and synchronizing them. 4b, 4b,..., 4c, 4c,..., 4d, 4d,... Are recorded in the synchronized databases 11a, 11b, 11c, and 11d. The contents of the databases 11a, 11b, 11c, and 11d to be changed are changed. Therefore, synchronizing the contents of the databases 11a, 11b, 11c, and 11d, that is, ensuring that the contents of any data read from the databases 11a, 11b, 11c, and 11d coincide with each other for a certain period of time. difficult.

  Accordingly, each of the in-vehicle communication devices 1a, 1b, 1c, and 1d constituting the in-vehicle communication system according to the present invention is provided with the buffers 12a, 12b, 11c, and 11d for the databases 11a, 11b, 11c, and 11d. The data transmitted from the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... are temporarily recorded in the respective buffers 12a, 12b, 12c, 12d. The solid arrows in FIG. 1 represent the flow of data when data transmitted from the ECUs 4a, 4a is temporarily recorded in the buffer 12a of the in-vehicle communication device 1a.

  Thereby, when the process for a synchronization is completed, the content of the database 11a, 11b, 11c, 11d of each vehicle-mounted communication apparatus 1a, 1b, 1c, 1d is synchronized with the same content. Each in-vehicle communication device 1a, 1b, 1c, and 1d reflects the data recorded in the buffers 12a, 12b, 12c, and 12d in the databases 11a, 11b, 11c, and 11d, respectively, after the processing for synchronization is completed. The process for synchronization is executed again, and this is repeated at regular intervals.

  In addition, when each ECU 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... uses data, the data is separately transmitted to each in-vehicle communication line 3a, 3b, 3c, 3d. When the connected ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... need to have the same contents, the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ..., the data read from the databases 11a, 11b, 11c, 11d of the respective in-vehicle communication devices 1a, 1b, 1c, 1d are transmitted. In addition, when each ECU 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... uses data, when the data needs to be the latest updated data, .., 4c, 4c,..., 4d, 4d,... Are read from the buffers 12a, 12b, 12c, and 12d included in the in-vehicle communication devices 1a, 1b, 1c, and 1d, respectively. The transmitted data is transmitted. The broken-line arrows in FIG. 1 represent the flow of data when the data read from the database 11a of the in-vehicle communication device 1a and the data read from the buffer 12a are transmitted to the ECUs 4a and 4a, respectively.

  Details of each process will be described below.

  FIG. 2 shows the interior of the in-vehicle communication devices 1a, 1b, 1c, 1d and ECUs 4a, 4a,..., 4b, 4b,..., 4c, 4c,. It is a block diagram which shows a structure.

  The in-vehicle communication device 1a is connected to a control unit 10a that controls the operation of each component shown below, a power supply circuit 13a that supplies power to each component, a storage unit 14a that includes a memory, and an in-vehicle communication line 3a. The first communication control unit 15a and the second communication control unit 16a connected to the communication line 2 are provided. The other in-vehicle communication devices 1b, 1c, and 1d have the same internal configuration as the in-vehicle communication device 1a, and thus detailed description thereof is omitted.

  The control unit 10a receives power supply from a vehicle alternator, a battery, or the like (not shown) via the power supply circuit 13a, reads and executes a control program stored in the storage unit 14a, and controls each component unit.

  The storage unit 14a is provided with a storage area for a database 11a that records data received by the control unit 10a from the ECUs 4a, 4a,. The controller 10a reads the corresponding specific measured value, calculated value, and control value from the received data for each attribute such as “wheel speed” and records it in the database 11a. In the embodiment described below, the structures of the databases 11a, 11b, 11c, and 11d are determined. That is, an area (address) in the databases 11a, 11b, 11c, and 11d is set for each data. For example, the data recorded at the address 1 in the database 11a is “wheel speed”. The data recorded at address 3 in the address can be specified as “oil temperature”.

  However, the present invention is not limited to this, and the database 11a may have a configuration in which identification information of data attributes such as attribute names and specific values associated with the identification information are recorded in pairs.

  Further, the storage unit 14a is provided with a buffer 12a for temporarily recording data transmitted from the ECUs 4a, 4a,... Connected via the in-vehicle communication line 3a. The buffer 12a may be a recording area provided separately from the recording area provided for the database 11a in the storage unit 14a, or a part of the recording area provided for the database 11a may be used as the buffer 12a. It may be. Further, the database 11a and the buffer 12a may be configured to be secured in a storage area such as a physically different memory.

  The first communication control unit 15a realizes data transmission / reception with the ECUs 4a, 4a,... Connected via the in-vehicle communication line 3a. The control unit 10a receives data from each of the ECUs 4a, 4a,... By the first communication control unit 15a, and transmits the data.

  In addition, the second communication control unit 16a realizes data transmission / reception with other in-vehicle communication devices 1b, 1c, and 1d connected via the communication line 2. The control part 10a transmits the data read from the database 11a or the buffer 12a by the second communication control part 16a and receives the data transmitted from the other in-vehicle communication devices 1b, 1c, 1d.

  The ECU 4a includes a control unit 40 that controls the operation of each component shown below, a power supply circuit 41 that supplies power to each component, a storage unit 42 including a memory, and a communication connected to the in-vehicle communication line 3a. The control part 43, the input part 44 which inputs the signal from the sensor which is not shown in figure, and the output part 45 which outputs a control signal to the control object apparatus which is not shown in figure are provided. Since the other ECUs 4b, 4c, and 4d have the same configuration as the ECU 4a, detailed description thereof is omitted. Note that, depending on the ECU, only one of the input unit 44 and the output unit 45 may be provided.

  The control unit 40 of the ECU 4a is supplied with electric power from a vehicle alternator, battery, or the like (not shown) via a power supply circuit 41, and represents a measurement value from a sensor (not shown) connected to the ECU 4a via an input unit 44. Is detected, and a control signal is transmitted to the device to be controlled connected to the ECU 4a via the output unit 45.

  In the storage unit 42, the control unit 40 temporarily stores various information generated in the course of processing or measurement values represented by signals input from sensors, for example. In addition, when receiving data used for processing from the in-vehicle communication device 1a connected via the in-vehicle communication line 3a, the storage unit 42 uses the data read from the database 11a or from the buffer 12a. Specification information for specifying whether to use the read data is stored. The control unit 40 reads the designation information stored in the storage unit 42 and transmits the designation information read to the in-vehicle communication device 1a via the communication control unit 43 and the in-vehicle communication line 3a.

  The ECU 4a can be switched from the outside whether to use data read from the database 11a by a dip switch or the like, or to use data read from the buffer 12a. The configuration may be such that the on / off state is detected and the corresponding designation information is transmitted to the in-vehicle communication device 1a via the communication control unit 43.

  The communication control unit 43 has a network controller chip and realizes communication with the in-vehicle communication line 3a. The control unit 40 of the ECU 4a detects a signal from a sensor (not shown) at regular intervals of 1 millisecond, for example, and transmits data including a physical quantity value indicated by the detected signal via the communication control unit 43. The control unit 40 of the ECU 4a receives data transmitted from the in-vehicle communication device 1a via the communication control unit 43.

  In the in-vehicle communication system of the present invention configured as described above, processing for synchronizing the databases 11a, 11b, 11c, and 11d of the in-vehicle communication devices 1a, 1b, 1c, and 1d with the same contents will be described below.

  FIG. 3 shows that the control unit 10a of the in-vehicle communication device 1a in the first embodiment receives data from the other in-vehicle communication devices 1b, 1c, 1d, and the database 11a has the same contents as the other databases 11b, 11c, 11d. It is a flowchart which shows the example of the process sequence to synchronize. Since the processing procedures of the control units 10b, 10c, and 10d of the in-vehicle communication devices 1b, 1c, and 1d are the same as the processing procedure of the control unit 10a of the in-vehicle communication device 1a, detailed description thereof is omitted.

  The control unit 10a of the in-vehicle communication device 1a determines whether or not to start the process for synchronization depending on whether or not a predetermined period has arrived (step S11). The predetermined cycle is set and stored in the storage unit 14a of the in-vehicle communication device 1a, and the control unit 10a of the in-vehicle communication device 1a functions as a timer to determine whether or not the predetermined cycle has arrived. It is determined whether or not to start.

  If the control unit 10a of the in-vehicle communication device 1a determines that the process for synchronization is not started (S11: NO), the process returns to step S11 and waits until it is determined that the process for synchronization is started.

  When the control unit 10a of the in-vehicle communication device 1a determines to start the process for synchronization (S11: YES), the data recorded in the buffer 12a is read (step S12), and the read data is stored in the database 11a. (Step S13). The data read in step S12 is recorded in the database 11a, so that the data transmitted from the ECUs 4a, 4a,... Connected via the in-vehicle communication line 3a and temporarily recorded in the buffer 12a is updated. The reflected data is reflected in the database 11a.

  Next, the control unit 10a of the in-vehicle communication device 1a determines whether or not it is the number for transmitting data from the database 11a reflecting the data in the buffer 12a to the other in-vehicle communication devices 1b, 1c, and 1d ( Step S14). In step S14, it is determined whether or not it is the transmission number. Priorities are set for the in-vehicle communication devices 1a, 1b, 1c, and 1d, and the in-vehicle communication devices 1a, 1b, 1c, and 1d attempt transmission. If the transmission is successful, it may be determined whether the transmission is successful or unsuccessful, and if it is successful, it may be determined that it is the transmission number of itself. The in-vehicle communication devices 1a, 1b, 1c, and 1d are set in the transmission order and stored in the storage units 14a, 14b, 14c, and 14d, and the control unit 10a of each in-vehicle communication device 1a performs the synchronization process. Based on whether or not transmission from other in-vehicle communication devices 1b, 1c, and 1d has been performed since it is determined to start, and based on the transmission order read from the storage unit 14a, it is determined whether it is the number of the transmission itself. May be.

  When the control unit 10a of the in-vehicle communication device 1a determines that it is not the turn to transmit (S14: NO), the second communication control is performed on the data transmitted from the other in-vehicle communication devices 1b, 1c, and 1d via the communication line 2. It is determined whether it is received by the unit 16a (step S15). When the control unit 10a of the in-vehicle communication device 1a determines that the data transmitted from the other in-vehicle communication devices 1b, 1c, and 1d via the communication line 2 has not been received (S15: NO), the process is performed in step S15. It returns to and waits until it judges that the data transmitted via the communication line 2 from other vehicle-mounted communication apparatus 1b, 1c, 1d were received.

  When the control unit 10a of the in-vehicle communication device 1a determines that data transmitted from the other in-vehicle communication devices 1b, 1c, and 1d via the communication line 2 has been received (S15: YES), the received data is stored in the database 11a. Is recorded and reflected (step S16), and the process proceeds to step S18 described later.

  On the other hand, when the control unit 10a of the in-vehicle communication device 1a determines in step S14 that it is a transmission number (S14: YES), the data read from the buffer 12a in step S13 is reflected in the database 11a. The second communication control unit 16a transmits the predetermined data to the other in-vehicle communication devices 1b, 1c, 1d connected via the communication line 2 (step S17).

  Next, the control unit 10a of the in-vehicle communication device 1a performs processing for transmitting predetermined data in the database 11a and processing for recording data transmitted from all the other in-vehicle communication devices 1b, 1c, and 1d in the database 11a. It is determined whether or not the synchronization process has been completed (step S18). When the control unit 10a of the in-vehicle communication device 1a determines that the synchronization process is not completed (S18: NO), the process from step S14 to step S17 is continued.

  When the control unit 10a of the in-vehicle communication device 1a determines that the synchronization process is completed (S18: YES), the process ends.

  In addition, the data which the control part 10a of the vehicle-mounted communication apparatus 1a transmits to other vehicle-mounted communication apparatus 1b, 1c, 1d in step S17 was made into the predetermined data in the database 11a. This is because the ECUs 4a, 4a,... Connected to the databases 11a, 11b, 11c, 11d of the in-vehicle communication devices 1a, 1b, 1c, 1d via the in-vehicle communication lines 3a, 3b, 3c, 3d,. .., 4c, 4c,..., 4d, 4d,... Are generally determined so that the data to be updated do not overlap each other. Therefore, the control unit 10a of the in-vehicle communication device 1a reads out data determined as data updated by the ECUs 4a, 4a,... Connected to the in-vehicle communication device 1a in the entire database 11a as predetermined data. Send. In this case, the control units 10b, 10c, and 10d of the other in-vehicle communication devices 1b, 1c, and 1d use the data transmitted from the in-vehicle communication device 1a as the data determined by the in-vehicle communication device 1a as the databases 11b, 11c, and 11d. To record.

  The control unit 10a of the in-vehicle communication device 1a transmits the entire database 11a as predetermined data, and the other control units 10b, 10c, and 10d of the in-vehicle communication devices 1b, 1c, and 1d are transmitted from the in-vehicle communication device 1a. Data determined by the in-vehicle communication device 1a may be read from the data and recorded in the respective databases 11b, 11c, and 11d.

  By the processing of the control unit 10a of the in-vehicle communication device 1a and the processing of the control units 10b, 10c, 10d of the in-vehicle communication devices 1b, 1c, 1d shown in the flowchart of FIG. 3, each of the databases 11a, 11b, 11c, 11d Data is sent and received and exchanged and synchronized to the same content.

  Incidentally, as described above, a certain time is required from the start of synchronization processing to the end of each in-vehicle communication device 1a, 1b, 1c, 1d. Each ECU 4a, 4a,..., 4b, 4b,..., 4c, 4c, while synchronization processing is being executed by the control units 10a, 10b, 10c, 10d of the in-vehicle communication devices 1a, 1b, 1c, 1d. ..., 4d, 4d, ... are newly transmitted. When these data are immediately recorded and reflected in the databases 11a, 11b, 11c, and 11d, new data is recorded during the execution of the synchronization process. Therefore, it cannot be ensured that there is a time when the contents of arbitrary data read from the databases 11a, 11b, 11c, and 11d coincide with each other.

  Therefore, the control units 10a, 10b, 10c, and 10d of the in-vehicle communication devices 1a, 1b, 1c, and 1d according to the present invention are respectively connected to the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, Data transmitted from... Is temporarily recorded in the buffers 12a, 12b, 12c, and 12d.

  FIG. 4 shows an example of a processing procedure in which the control unit 10a of the in-vehicle communication device 1a according to the first embodiment receives and records data transmitted from the ECUs 4a, 4a,... Connected via the in-vehicle communication line 3a. It is a flowchart which shows. Since the processing procedures of the control units 10b, 10c, and 10d of the in-vehicle communication devices 1b, 1c, and 1d are the same as the processing procedure of the control unit 10a of the in-vehicle communication device 1a, detailed description thereof is omitted.

  The control unit 10a of the in-vehicle communication device 1a determines whether data transmitted from the ECUs 4a, 4a,... Connected via the in-vehicle communication line 3a has been received (step S21). When the control unit 10a of the in-vehicle communication device 1a determines that the data transmitted from the ECUs 4a, 4a,... Has not been received (S21: NO), the process returns to step S21 and is transmitted from the ECUs 4a, 4a,. Wait until it is determined that the received data has been received.

  When it is judged that the control part 10a of the vehicle-mounted communication apparatus 1a received the data transmitted from ECU4a, 4a, ... (S21: YES), the received data are recorded on the buffer 12a (step S22), and a process is complete | finished. To do.

  The data recorded in the buffers 12a, 12b, 12c, and 12d is recorded in the database 11a and appropriately reflected during synchronization processing by the control unit 10a as shown in the flowchart of FIG.

  As shown in the flowcharts of FIGS. 3 and 4, the contents of the databases 11a, 11b, 11c, and 11d are the same by the processing of the control units 10a, 10b, 10c, and 10d of the in-vehicle communication devices 1a, 1b, 1c, and 1d. In addition, for the databases 11a, 11b, 11c, and 11d synchronized with the same content, the updated data in the buffers 12a, 12b, 12c, and 12d, that is, the databases 11a, 11b, 11c, and 11d On the other hand, data corresponding to the difference from the previous synchronization to the next synchronization is recorded.

  Therefore, the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., connected to the in-vehicle communication devices 1a, 1b, 1c, 1d via the in-vehicle communication lines 3a, 3b, 3c, 3d. 4d, 4d,... Use data read from the databases 11a, 11b, 11c, 11d synchronized with the same content as the other groups, or are synchronized with the same content as the other groups. Although there is a possibility that the data read from the buffers 12a, 12b, 12c, and 12d, which is the latest data, may be used, it can be selected based on the designation information stored in the storage unit 42.

  FIG. 5 shows a processing procedure for transmitting and receiving data between the ECUs 4a, 4a,... Connected to the in-vehicle communication line 3a and the in-vehicle communication apparatus 1a connected via the in-vehicle communication line 3a in the first embodiment. It is a flowchart which shows the example of.

  The control unit 40 of the ECU 4a transmits, by the communication control unit 43, the request for data to be used and the designation information read from the storage unit 42 regarding the data to be used to the in-vehicle communication device 1a connected via the in-vehicle communication line 3a. (Step S31).

  The control unit 10a of the in-vehicle communication device 1a receives the data request and designation information transmitted from one of the ECUs 4a, 4a,... Connected via the in-vehicle communication line 3a by the first communication control unit 15a. (Step S32), it is determined whether or not the designation information received in Step S32 designates the use of data read from the database 11a (Step S33).

  When the control unit 10a of the in-vehicle communication device 1a determines that the designation information received in step S32 designates the use of data read from the database 11a (S33: YES), the control unit 10a receives in step S32. Data is read from the database 11a based on the requested data (step S34). On the other hand, when the control unit 10a of the in-vehicle communication device 1a determines that the designation information received in step S32 does not designate use of the data read from the database 11a (S33: NO), step S32 The data is read from the buffer 12a based on the data request received in step S35.

  The control unit 10a of the in-vehicle communication device 1a transmits the data read in step S34 or step S35 to the ECU 4a by the first communication control unit 15a via the in-vehicle communication line 3a (step S36).

  The control part 40 of ECU4a receives the data transmitted from the vehicle-mounted communication apparatus 1a by the communication control part 43 (step S37), and complete | finishes a process.

  By the processing shown in the flowchart of FIG. 5, the ECU 4a has the same content as the data acquired by each of the ECUs 4b, 4b,..., 4c, 4c, ..., 4d, 4d,. The data read from 11a or the ECU 4b, 4b,..., 4c, 4c,..., 4d, 4d,. Any one of the data read from the buffer 12a in which the data with high real-time property recorded is recorded can be designated and used.

(Embodiment 2)
In the first embodiment, the vehicle-mounted communication device 1a buffers the database 11a to other vehicle-mounted communication devices 1b, 1c, and 1d in order to synchronize the contents of the databases 11a, 11b, 11c, and 11d that the vehicle-mounted communication device 1a has. The data recorded in 12a is recorded and reflected, and predetermined data is read from the database 11a and transmitted. On the other hand, in the second embodiment described below, the in-vehicle communication device 1a reads predetermined data from the database 11a in order to synchronize the contents of the databases 11a, 11b, 11c, and 11d that each has. Instead, the data recorded in the buffer 12a is transmitted.

  Moreover, in Embodiment 1, ECU4a, 4a, ... transmits the designation | designated information memorize | stored in the memory | storage part 42 with the request | requirement of data, and the vehicle-mounted communication apparatus 1a of the database 11a designated by the received designation | designated information or the buffer 12a The requested data is read from any recording area and transmitted. On the other hand, in the second embodiment described below, the ECU 4a transmits only a data request, and the in-vehicle communication device 1a is a database based on the designation information stored in the storage unit 14a for each ECU 4a, 4a,. Data is read from 11a or buffer 12a and transmitted.

  Since the configuration of the in-vehicle communication system in the second embodiment is the same as that of the in-vehicle communication system in the first embodiment, detailed description thereof is omitted. In the second embodiment, the contents of data transmitted to other in-vehicle communication devices 1a, 1b, 1c, 1d to which the in-vehicle communication devices 1a, 1b, 1c, 1d are connected via the communication line 2, and the respective in-vehicle communication devices Data transmitted from the communication devices 1a, 1b, 1c, 1d to the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ..., the databases 11a, 11b, 11c, 11d and the buffer 12a, 12b, 12c, and 12d are different from each other in the process of determining from which to read, so that each of the in-vehicle communication devices 1a, 1b, 1c, and 1d and the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, .., 4d, 4d,... Will be described using the same reference numerals as those in the first embodiment.

  In the second embodiment, the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... store data used for processing via the in-vehicle communication line 3a. When receiving from the connected in-vehicle communication device 1a, designation information for designating the database 11a or the buffer 12a is not stored. On the other hand, the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c connected to the storage units 14a, 14b, 14c, 14d of the in-vehicle communication devices 1a, 1b, 1c, 1d in the second embodiment, respectively. 4c,..., 4d, 4d,... Is stored as designation information for designating one of the databases 11a, 11b, 11c, and 11d or the buffers 12a, 12b, 12c, and 12d as a recording area for reading out data to be transmitted. Yes.

  In FIG. 6, the control unit 10a of the in-vehicle communication device 1a according to the second embodiment receives data from the other in-vehicle communication devices 1b, 1c, 1d, and the database 11a has the same contents as the other databases 11b, 11c, 11d. It is a flowchart which shows the example of the process sequence to synchronize. Since the processing procedures of the control units 10b, 10c, and 10d of the in-vehicle communication devices 1b, 1c, and 1d are the same as the processing procedure of the control unit 10a of the in-vehicle communication device 1a, detailed description thereof is omitted.

  The processing procedure shown in the flowchart of FIG. 6 is the same as that in the first embodiment except for the processing steps S41 to S46 and S48 other than the processing to transmit to the other in-vehicle communication devices 1b, 1c, and 1d in step S47. Since it is the same as the process procedure of step S11-step S16 and step S18 shown in the flowchart of FIG. 3, detailed description is abbreviate | omitted.

  If the control unit 10a of the in-vehicle communication device 1a determines that it is the transmission number in step S44 (S44: YES), the data read from the buffer 12a in step S43 is connected via the communication line 2. When the second communication control unit 16a transmits to the other in-vehicle communication devices 1b, 1c, and 1d (step S47), it is determined whether or not the synchronized process is completed and it is determined that the process is completed (S48: YES), the process ends.

  As a result, data transmitted from the ECUs 4a, 4a,... After the database 11a is synchronized with the other databases 11b, 11c, 11d, that is, data from the buffer 12a in which only difference data from the previous synchronization is recorded. Since the data is transmitted, the amount of data transmitted / received through the communication line 2 is reduced, the communication load is reduced, and the processes of synchronizing the databases 11a, 11b, 11c, and 11d of the in-vehicle communication devices 1a, 1b, 1c, and 1d, respectively. Can be executed.

  In the second embodiment, as in the first embodiment, the contents of the databases 11a, 11b, 11c, and 11d are the same by the processing of the control units 10a, 10b, 10c, and 10d of the in-vehicle communication devices 1a, 1b, 1c, and 1d. The updated data is recorded in the buffers 12a, 12b, 12c, and 12d with respect to the databases 11a, 11b, 11c, and 11d that are synchronized with the contents of the same.

  Therefore, the ECUs 4a, 4a,... Connected via the in-vehicle communication lines 3a, 3b, 3c, 3d according to the designation information stored in the storage unit 14a of the in-vehicle communication devices 1a, 1b, 1c, 1d. 4b, 4b,..., 4c, 4c,..., 4d, 4d,..., Whether data read from the databases 11a, 11b, 11c, and 11d synchronized with the same contents as other groups is used. Alternatively, it is selected whether to use the data read from the buffers 12a, 12b, 12c, and 12d, which is the latest data, which may not be synchronized with the same contents as other groups.

  Next, data transmission processing from the in-vehicle communication device 1a to the ECU 4a in the second embodiment will be described. FIG. 7 shows a processing procedure for transmitting and receiving data between the ECUs 4a, 4a,... Connected to the in-vehicle communication line 3a and the in-vehicle communication apparatus 1a connected via the in-vehicle communication line 3a in the second embodiment. It is a flowchart which shows the example of.

  The control part 40 of ECU4a transmits the request | requirement of the data to be used by the communication control part 43 to the vehicle-mounted communication apparatus 1a connected via the in-vehicle communication line 3a (step S51).

  The control unit 10a of the in-vehicle communication device 1a receives a request for data transmitted from one of the ECUs 4a, 4a,... Connected via the in-vehicle communication line 3a by the first communication control unit 15a (step S52). ), The designation information stored in the ECU 4a that has transmitted the data request is read out, and whether or not the stored designation information specifies that the data read out from the database 11a is to be used. Judgment is made (step S53).

  When the control unit 10a of the in-vehicle communication device 1a determines that the stored designation information designates the use of data read from the database 11a (S53: YES), the control unit 10a has received it in step S52. Data is read from the database 11a based on the data request (step S54). On the other hand, when the control unit 10a of the in-vehicle communication device 1a determines that the stored designation information does not designate the use of the data read from the database 11a (S53: NO), the control unit 10a receives in step S52. Data is read from the buffer 12a based on the requested data (step S55).

  The control unit 10a of the in-vehicle communication device 1a transmits the data read in step S54 or step S55 to the ECU 4a by the first communication control unit 15a via the in-vehicle communication line 3a (step S56).

  The control part 40 of ECU4a receives the data transmitted from the vehicle-mounted communication apparatus 1a by the communication control part 43 (step S57), and complete | finishes a process.

  By the processing shown in the flowchart of FIG. 7, the control unit 10a of the in-vehicle communication device 1a transmits data to be used by the ECU 4a to the ECUs 4b, 4b,..., 4c, 4c,. 4d,..., Data read from the database 11a having the same content as the data acquired, or each ECU 4b, 4b,..., 4c, 4c,. Any of the data read from the buffer 12a in which updated real-time data is recorded, which may not be the same as the data to be acquired, can be designated.

  As shown in the first and second embodiments, the storage units 14a, 14b, 14c, 14d of the in-vehicle communication devices 1a, 1b, 1c, 1d, the databases 11a, 11b, 11c, 11d and the buffers 12a, 12b, 12c, The data and contents used by the other ECUs 4b, 4b,..., 4c, 4c,..., 4d, 4d,. The ECU 4a that uses data that is important to do and the ECU 4a that uses data that is important to real time can be connected to the same in-vehicle communication line 3a.

  In Embodiments 1 and 2, the storage units 14a, 14b, 14c, and 14d of the in-vehicle communication devices 1a, 1b, 1c, and 1d are stored in the in-vehicle communication devices 1a, 1b, 1c, and 11d, respectively. 1d mutually transmits the data in the databases 11a, 11b, 11c, and 11d or the data recorded in the buffers 12a, 12b, 12c, and 12d, and reads and records predetermined data set from the transmitted data. Or the entire transmitted data is recorded as predetermined data to be synchronized. However, the method of synchronizing the contents of the databases 11a, 11b, 11c, and 11d of the in-vehicle communication devices 1a, 1b, 1c, and 1d with the same contents in the in-vehicle communication system of the present invention is not limited to the method described above. . For example, when the in-vehicle communication devices 1a, 1b, 1c, and 1d are sequentially connected to the communication line 2 in a ring shape, the in-vehicle communication device 1b and 1c adjacent to the predetermined in-vehicle communication device 1b and 1c are started from the in-vehicle communication device 1a. , 1d, and the last in-vehicle communication device 1d aggregates the contents of the databases 11a, 11b, 11c, 11d of all the in-vehicle communication devices 1a, 1b, 1c, 1d. A configuration in which the database aggregated by the in-vehicle communication device 1d is transmitted to the adjacent in-vehicle communication device 1c, is further transmitted in order to 1b, 1a, and is received and updated by the in-vehicle communication device 1a. But you can.

  When each of the in-vehicle communication devices 1a, 1b, 1c, and 1d synchronizes the contents of the databases 11a, 11b, 11c, and 11d with the same content, the in-vehicle communication devices 1a, 1b, 1c, and 1d in the first embodiment are used. Is configured to read and transmit predetermined data from the entire databases 11a, 11b, 11c, and 11d, and to transmit data recorded in the buffers 12a, 12b, 12c, and 12d in the second embodiment. In addition, when each vehicle-mounted communication device 1a, 1b, 1c, 1d transmits data to each ECU 4a, 4a,..., 4b, 4b,..., 4c, 4c,. .., 4c, 4c,..., 4d, 4d,... Or databases 12a, 11b, 11c, 11d or buffers 12a, 12b, 12c, 12d based on the designation information transmitted from each ECU 4a, 4a,. In the second embodiment, ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... are sent to the in-vehicle communication devices 1a, 1b, 1c, 1d, respectively. Data is read from the databases 11a, 11b, 11c, and 11d or the buffers 12a, 12b, 12c, and 12d based on the designation information stored every time and transmitted. However, the present invention is not limited to the combination in Embodiments 1 and 2 with respect to the main body for storing data and designation information transmitted when synchronizing the database with the same contents.

  That is, when each in-vehicle communication device 1a, 1b, 1c, 1d synchronizes the contents of the databases 11a, 11b, 11c, 11d with the same content, in the first embodiment, each in-vehicle communication device 1a, 1b, 1c, 1d Reads and transmits predetermined data from the entire databases 11a, 11b, 11c, and 11d, and each of the in-vehicle communication devices 1a, 1b, 1c, and 1d transmits the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, .., 4d, 4d,..., 4d, 4d,..., 4d, 4d,..., 4d, 4d,. A configuration may be employed in which data is read from the databases 11a, 11b, 11c, and 11d or the buffers 12a, 12b, 12c, and 12d and transmitted based on the designation information stored for each.

  Moreover, in Embodiment 1 and 2, each vehicle-mounted communication apparatus 1a, 1b, 1c, 1d is ECU4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ... during synchronization processing. All the data transmitted from is recorded in the buffers 12a, 12b, 12c, 12d. However, the present invention is not limited to this, and depending on the data transmitted from the ECUs 4a, 4a, ..., 4b, 4b, ..., 4c, 4c, ..., 4d, 4d, ..., the databases 11a, 11b, 11c, 11d It may be configured to record. For example, a means for detecting a change in the content of transmitted data (value of numerical information, etc.) is further provided. When the content has not changed, it is recorded in the database, and when the content has changed, the buffers 12a, 12b, The structure recorded to 12c, 12d may be sufficient.

It is a block diagram which shows the structure of the vehicle-mounted communication system which concerns on this invention. It is a block diagram which shows the internal structure of the vehicle-mounted communication apparatus and ECU which comprise the vehicle-mounted communication system which concerns on this invention. It is a flowchart which shows the example of the process sequence which the control part of the vehicle-mounted communication apparatus in Embodiment 1 receives data from another vehicle-mounted communication apparatus, and synchronizes a database with the same content as another database. 4 is a flowchart illustrating an example of a processing procedure in which a control unit of the in-vehicle communication device according to Embodiment 1 receives and records data transmitted from an ECU connected via an in-vehicle communication line. 3 is a flowchart illustrating an example of a processing procedure for transmitting and receiving data between an ECU connected to an in-vehicle communication line and an in-vehicle communication apparatus connected via the in-vehicle communication line in the first embodiment. It is a flowchart which shows the example of the process sequence which the control part of the vehicle-mounted communication apparatus in Embodiment 2 receives data from another vehicle-mounted communication apparatus, and synchronizes a database to the same content as another database. 10 is a flowchart illustrating an example of a processing procedure for transmitting and receiving data between an ECU connected to an in-vehicle communication line and an in-vehicle communication apparatus connected via the in-vehicle communication line in the second embodiment.

Explanation of symbols

1a, 1b, 1c, 1d In-vehicle communication device 10a, 10b, 10c, 10d Control unit 11a, 11b, 11c, 11d Database 12a, 12b, 12c, 12d Buffer 14a, 14b, 14c, 14d Storage unit 2 Communication line 3a, 3b , 3c, 3d In-vehicle communication line 4a, 4b, 4c, 4d ECU
40 Control unit

Claims (8)

In an in-vehicle communication system including a plurality of in-vehicle devices that transmit and receive data and an in-vehicle communication line that connects the in-vehicle devices divided into a plurality of groups for each group,
Each group is connected to the in-vehicle communication line for each group, and includes an in-vehicle communication apparatus having a database for recording data transmitted and received via each in-vehicle apparatus and the in-vehicle communication line, and a buffer for the database.
Each in-vehicle communication device
It is connected via a communication line different from the in-vehicle communication line,
Means for transmitting predetermined data of data recorded in the database or the buffer to another in-vehicle communication device via the communication line;
Means for recording data transmitted from the other in-vehicle communication device via the communication line in the database;
Means for recording data transmitted from the in-vehicle device connected via the in-vehicle communication line in the buffer;
A vehicle-mounted communication system comprising: means for transmitting data read from the database or the buffer to a vehicle-mounted device connected via the in-vehicle communication line. The in-vehicle communication system according to claim 1, wherein each of the in-vehicle communication devices transmits only data recorded in the buffer as the predetermined data. The in-vehicle device is
Means for storing designation information for designating a recording area of either the database or the buffer;
Means for transmitting the designation information to the in-vehicle communication device,
The in-vehicle communication device is
Means for receiving designation information transmitted from the in-vehicle device;
The vehicle-mounted communication system according to claim 1, further comprising: means for transmitting data read from a recording area specified by the received specification information to the vehicle-mounted device via the in-vehicle communication line. . The in-vehicle communication device is
For each in-vehicle device, the database or the recording area is stored as a recording area for reading data to be transmitted,
The in-vehicle communication system according to any one of claims 1 to 3, wherein data read from the stored recording area is transmitted for each in-vehicle device. It includes a plurality of vehicle devices for sending and receiving data, and a vehicle in the communication line to connect the vehicle device which is divided into a plurality of groups for each respective group, further, is connected to the vehicle communication line for each group A plurality of in-vehicle communication devices each having a database for recording data to be transmitted to and received from each in-vehicle device and a buffer for the database, the plurality of in-vehicle communication devices being different from the in-vehicle communication line similar vehicle communication systems are connected via a communication line, the in-vehicle communication device, in-vehicle communication method for transmitting to the in-vehicle device included the data transmitted from the in-vehicle device included in the first group of the other group I met with,
The vehicle communication device included in the group of the one,
A part or all of data transmitted from the in-vehicle device via the in-vehicle communication line is recorded in a buffer that the device has,
Record the data recorded in the buffer in its own database,
It transmits through the database or the communication line a predetermined data among the data recorded in the buffer to the in-vehicle communication device provided in the other groups,
The in-vehicle communication device provided in the other group records predetermined data transmitted from the in-vehicle communication device provided in the one group in its own database,
The other in-vehicle communication device reads out data from the database or its own buffer and transmits the data to the in-vehicle device via the in-vehicle communication line . The in-vehicle communication method according to claim 5, wherein each of the in-vehicle communication devices transmits only the data recorded in the buffer as the predetermined data. The in-vehicle device is
Sending designation information for designating a recording area of either the database or the buffer to the in-vehicle communication device,
The in-vehicle communication device is
Receiving the designation information transmitted from the in-vehicle device,
Vehicle communication method according to output data read from the recording area specified in claim 5 or 6, characterized in that transmitted to the vehicle device by the received the designation information. Each of the in-vehicle communication devices is
For each in-vehicle device, store either the database or the recording area as a recording area for reading data to be transmitted,
The in-vehicle communication method according to any one of claims 5 to 7, wherein the data read from the stored recording area is transmitted for each in-vehicle device.

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