JP5240660B2 - Gateway device - Google Patents

Description

  More specifically, the present invention relates to a gateway device used for an in-vehicle network.

  2. Description of the Related Art Conventionally, in a vehicle, an in-vehicle network that interconnects the in-vehicle devices has been constructed in order to control the in-vehicle devices mounted on the vehicle. Generally, the in-vehicle network includes a plurality of communication buses that are connected to the in-vehicle device and handle predetermined data. When data transmission / reception between the communication buses is necessary, a gateway device provided between the communication buses performs a process of relaying the data from one communication bus to the other communication bus.

An example of a gateway device that performs the relay processing as described above is disclosed in Patent Document 1. The communication gateway device disclosed in Patent Literature 1 compares stored information stored in advance with received data. Then, the communication gateway device updates the stored information with the received data and relays the data only when the stored information and the data are different as a result of the comparison. In other words, the communication gateway device performs a process of stopping the data relay while the same data is continuously received.
International Publication No. 99/22494 Pamphlet

  By the way, in the in-vehicle device mounted on the vehicle and connected to the communication bus as described above, if data reception is interrupted for a predetermined time, it is determined that some abnormality has occurred in the above-described in-vehicle network. In some cases, the operation mode is changed to execute an operation corresponding to the abnormality. For example, the interior light shifts to a sleep mode in order to reduce battery power consumption when reception of data indicating that the engine is ignited is interrupted for a predetermined time. Specifically, the room light that operates in the sleep mode does not light until data indicating ignition of the engine is received.

  When the communication gateway device disclosed in Patent Document 1 and the in-vehicle device having the mode change function are used in combination, the data used for the control of the in-vehicle device is fixed by the relay stop processing of the communication gateway device. May not be relayed to the in-vehicle device for a certain period of time. In such a case, the in-vehicle device erroneously determines that an abnormality has occurred in the in-vehicle network even though the in-vehicle network is actually operating normally, and changes the mode of operation inappropriately. May end up.

  For example, when the communication gateway device and the room light are used in combination, the room light may shift to the sleep mode and stop lighting even though no abnormality has occurred in the in-vehicle network. As described above, when the in-vehicle device such as the room light and the communication gateway device are used in combination, the in-vehicle device does not execute the operation desired by the user, and the user may feel inconvenient.

  The present invention has been made in view of the above problems, and an object thereof is to provide a gateway device capable of relaying data from one communication bus to the other communication bus at an appropriate timing.

  In order to solve the above problems, the present application adopts the following configuration. That is, the first invention is a gateway device that is connected to at least two or more communication buses and relays reception data received from any one of the communication buses to another communication bus each time reception data is received. In addition, the data comparison determination means (11, 12, S12) for determining whether or not the received data matches the previously received data, (a) the received data matches the previously received data If it is determined that the received data is not relayed, the received data is relayed to another communication bus. (B) If the received data matches the received data received last time and a predetermined condition is satisfied, the received data To the other communication bus, and (c) when the received data matches the previously received data and the condition is not satisfied, the received data is not relayed. 2, comprises a S13 through S17) and a gateway device.

  According to a second aspect of the present invention, in the first aspect of the present invention, the second aspect further includes a determination number counting unit that counts the number of determinations continuously determined that the received data matches the previously received data. (A) When it is determined that the received data does not match the previously received data, the received data is relayed to another communication bus, (d) the received data matches the previously received data, and If the number of determinations is greater than a predetermined threshold, the received data is relayed to another communication bus, and (e) the received data matches the received data received last time, and the number of determinations is less than the threshold, The received data is not relayed.

  According to a third invention, in the first invention, the relay means further comprises timer means for measuring an elapsed time from the time when the relay means relays, the relay means comprising (a) received data and previously received data received. When it is determined that they do not match, the received data is relayed to another communication bus. (F) If the received data matches the received data received last time and the elapsed time is greater than a predetermined threshold, the received data The data is relayed to another communication bus. (G) When the received data matches the previously received data and the elapsed time is less than or equal to the threshold value, the received data is not relayed.

  In a fourth aspect based on the first aspect, the data comparison / determination means overwrites the stored data with the received data when the received data and the stored data do not match the storage means for storing the received data as the stored data. When the received data and the stored data are compared with the stored data update means for updating the received data and the stored data, it is determined that the received data is the same as the previously received data, And storing data comparing means for determining that the received data does not match the previously received data when the received data and the stored data do not match.

  According to a fifth aspect of the present invention, in the first aspect of the invention, the data comparison means for determining whether the received data is data that needs to be relayed to another communication bus is further provided. Only if the received data is the data that needs to be relayed to another communication bus, it is determined whether or not the received data matches the previously received data. The received data is relayed only when the data needs to be relayed to the bus.

  In a sixth aspect based on the first aspect, the communication bus is a network line that interconnects on-vehicle devices mounted on the vehicle, and the gateway device is mounted on the vehicle.

  According to the first aspect, when the same data is continuously received, the relay of the data can be stopped until a predetermined condition is satisfied. In other words, data can be relayed as appropriate at a timing when the above condition is satisfied while reducing the amount of data traffic on the transfer destination communication bus. Therefore, for example, even if the in-vehicle device that automatically switches the operation mode to the emergency mode when data is not received for a predetermined time is connected to the data transfer destination communication bus, the in-vehicle device The relayed data can be received at a timing before the predetermined time elapses. That is, it is possible to prevent the in-vehicle device from switching the mode by mistake.

  According to the second invention, it is possible to appropriately relay data at the timing when the same data is received a predetermined number of times while reducing the amount of data traffic on the transfer destination communication bus. Therefore, it is possible to prevent the processing amount from being reduced and erroneous switching of the in-vehicle device by simple processing.

  According to the third invention, it is possible to appropriately relay data at a timing when a predetermined time has elapsed since data was relayed while reducing the amount of data traffic on the destination communication bus. That is, it is possible to prevent the processing amount from being reduced and erroneous switching of the in-vehicle device by simple processing.

  According to the fourth aspect of the invention, only when newly received data and previously stored data do not match, the stored data is overwritten and updated with the received data. Even if the stored data is not updated, it is possible to determine whether or not newly received data matches the previously received data. Therefore, it is possible to reduce the processing for updating the storage data as described above and reduce the processing amount.

  According to the fifth aspect of the present invention, it is possible to perform processing for determining whether or not only data that needs to be relayed to another communication bus matches the previously received data. Therefore, it is not necessary to perform the determination process for data that does not need to be relayed. Therefore, the processing amount can be reduced.

  According to the sixth aspect of the present invention, it is possible to prevent erroneous mode switching of the in-vehicle device while reducing the amount of data traffic on the vehicle network line.

(First embodiment)
Hereinafter, the gateway device 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

  First, the configuration of the gateway device 1 according to the first embodiment will be described with reference to FIG. FIG. 1 is a block diagram illustrating a configuration of an in-vehicle network including a gateway device 1 according to the first embodiment.

  As shown in FIG. 1, the communication bus 2 and the communication bus 3 are connected to each other via the gateway device 1. A plurality of in-vehicle control devices are connected to the communication bus 2 and the communication bus 3, respectively. In FIG. 1, as an example, a vehicle-mounted control device 21, a vehicle-mounted control device 22, and a vehicle-mounted control device 23 are connected to the communication bus 2. In addition, an in-vehicle control device 31, an in-vehicle control device 32, and an in-vehicle control device 33 are connected to the communication bus 3. In the first embodiment, an example will be described in which the gateway device 1, each communication bus, and each in-vehicle control device are all mounted in a vehicle and an in-vehicle network is constructed.

  The gateway device 1 is a relay device that relays data received from an in-vehicle control device connected to the communication bus 2 or the communication bus 3 via one communication bus to the other communication bus. The gateway device 1 includes a calculation unit 11, a storage unit 12, an interface circuit (not shown), and the like. The computing unit 11 is typically an information processing device such as a CPU (Central Processing Unit). The storage unit 12 is typically a storage device such as a memory.

  The communication bus 2 and the communication bus 3 are communication lines mounted on the vehicle. On the communication bus 2 and the communication bus 3, data output from each of the on-vehicle control devices flows.

  FIG. 2 is a diagram illustrating an example of a format of data transmitted and received by the in-vehicle control device according to the first embodiment. As shown in FIG. 2, the data transmitted and received by the in-vehicle control device is digital data represented by a predetermined bit length. The bit area of the data includes a header area 41, a command area 42, and a parameter area 43. The header area 41 is a bit area indicating the start of the data. The command area 42 is a bit area representing a command code indicating the type of the data. For example, when the data indicates the engine speed, a command code indicating the engine speed is stored in the command area 42. The parameter area 43 is a bit area indicating a parameter of the data. For example, when the data is data indicating the engine speed, numerical information on the engine speed such as 5000 rpm is stored in the parameter area 43.

  The in-vehicle control device 21, the in-vehicle control device 22, the in-vehicle control device 23, the in-vehicle control device 31, the in-vehicle control device 32, and the in-vehicle control device 33 are typically electronic control devices such as an ECU (Electronic Control Unit). Each vehicle-mounted control device controls vehicle-mounted devices such as an engine and a meter device mounted on the vehicle. Each in-vehicle control device outputs data used in the control processing of the other in-vehicle control device to the communication bus to which it is connected. Each in-vehicle control device receives data output from another in-vehicle control device from a communication bus to which it is connected, and performs control processing according to the data.

  For example, the in-vehicle control device 21 is a control device that controls an engine mounted on the vehicle. The on-vehicle control device 31 is a control device that controls the meter device. The meter device is a device that displays vehicle information to the driver. The in-vehicle control device 21 outputs data indicating the engine speed to the communication bus 2. The gateway device 1 receives data indicating the engine speed from the communication bus 2 and relays it to the communication bus 3 based on the processing described later. And the vehicle-mounted control apparatus 31 which controls a meter apparatus receives the data which show the engine speed from the communication bus 3, and changes the numerical value of the engine speed displayed with respect to a driver | operator according to the said data.

  Next, processing executed by the calculation unit 11 will be described with reference to FIG. FIG. 3 is an example of a flowchart illustrating processing executed by the calculation unit 11. For example, when the IG power supply of the vehicle is turned on and the power is supplied to the gateway device 1, the calculation unit 11 starts the process of the flowchart illustrated in FIG. 3. When the calculation part 11 starts the process of the flowchart shown in FIG. 3, first, the process of step S11 is executed.

  In step S <b> 11, the calculation unit 11 determines whether data has been received. Specifically, the arithmetic unit 11 determines whether data has been received from either the communication bus 2 or the communication bus 3 connected thereto. If it is determined that the data has been received, the arithmetic unit 11 advances the process to step S12. On the other hand, when it is determined that the data has not been received, the arithmetic unit 11 advances the process to step S18. Hereinafter, data received by the gateway device 1 is referred to as received data.

  In step S12, the computing unit 11 determines whether or not the received data is the same as the stored data. The stored data is received data stored in the storage unit 12 based on the processing in step S15 described later. The computing unit 11 reads the stored data stored in the storage unit 12 and determines whether the stored data and the received data are the same. More specifically, it is determined whether or not the contents of the command area 42 of the received data and the contents of the parameter area 43 of the received data match those of the stored data. When the contents of the command area 42 of the received data and the contents of the parameter area 43 of the received data match those of the stored data, the calculation unit 11 determines that the received data is the same as the stored data, and performs processing To step S13. On the other hand, if at least one of the contents of the command area 42 of the received data and the contents of the parameter area 43 of the received data does not match that of the stored data, the calculation unit 11 determines that the received data is different from the stored data. Then, the process proceeds to step S15.

  In step S13, the calculation unit 11 counts up the number counter value N. The number counter value N is a value indicating the number of times the same received data as the stored data is continuously received. The count counter value N is stored in the storage unit 12. The initial value of the number counter value N is preset to 1, for example. In step S13, the calculation unit 11 increases the number counter value N by a predetermined value. For example, the calculation unit 11 increases the value of the number counter value N by 1. When the process of step S13 is completed, the process proceeds to step S14.

  In step S14, the computing unit 11 determines whether or not the number counter value N is greater than a threshold value Nth. The threshold value Nth is an arbitrary constant stored in advance in the storage unit 12. The value of the threshold Nth is set to 3 in advance, for example. The computing unit 11 reads the values of the number counter value N and the threshold value Nth from the storage unit 12 and compares the magnitudes of the number counter value N and the threshold value Nth. If it is determined that the number counter value N is greater than the threshold value Nth, the arithmetic unit 11 advances the process to step S16. On the other hand, when it is determined that the number counter value N is equal to or less than the threshold value Nth, the arithmetic unit 11 returns the process to step S11.

  In step S15, the computing unit 11 updates the stored data. Specifically, the calculation unit 11 stores the storage data stored in the storage unit 12 by overwriting the received data. In addition, the calculating part 11 may memorize | store all the parts of reception data as memory | storage data, and may memorize | store only the part compared with reception data in said step S12 as memory | storage data. For example, the calculation unit 11 may store all parts of the received data including the header area 41, or may store only the command area 42 and the parameter area 43. When the process of step S15 is completed, the calculation unit 11 advances the process to step S16.

  According to the processing from step S11 to step S15, the calculation unit 11 updates the stored data only when the content of the received data has changed. That is, the stored data indicates the content of the received data received last time. Therefore, according to the processing from step S11 to step S15, every time data is received, the calculation unit 11 can determine whether or not the received data has the same content as the previously received data. When the received data has the same content as the previously received data, the calculation unit 11 counts how many times the received data having the content is received continuously.

  In step S <b> 16, the arithmetic unit 11 resets the number counter value N. Specifically, the arithmetic unit 11 returns the count counter value N to the initial value and stores it in the storage unit 12. When the process of step S16 is completed, the calculation unit 11 advances the process to step S17.

  In step S17, the arithmetic unit 11 relays the stored data to the other bus. Specifically, when receiving the received data from the communication bus 2, the arithmetic unit 11 transfers the received data to the communication bus 3. On the other hand, when receiving the received data from the communication bus 3, the arithmetic unit 11 transfers the received data to the communication bus 2. When the protocol of data flowing in the communication bus 2 and the protocol of data flowing in the communication bus 3 are different, the arithmetic unit 11 converts the received data into a protocol of the destination communication bus and transfers it. When the process of step S17 is completed, the calculation unit 11 advances the process to step S18.

  In step S <b> 18, the calculation unit 11 determines whether an end process has been executed. Specifically, the calculating part 11 determines whether the process which stops operation | movement of the gateway apparatus 1, such as the IG power supply of a vehicle being made into states other than ON, was performed. If it is determined that the termination process has not been executed, the arithmetic unit 11 returns the process to step S11. On the other hand, when it is determined that the end process has been executed, the arithmetic unit 11 ends the process of the flowchart of FIG.

  According to the processing from step S12 to step S15, the calculation unit 11 relays the received data when the received data is the same as the previously received data or when the same received data is continuously received a certain number of times. To do. In other words, the calculation unit 11 does not relay the received data until the same received data is continuously received a certain number of times.

  Next, with reference to FIG. 4 and FIG. 5, how the gateway device 1 relays received data will be described. FIG. 4 is a diagram showing the reception data received by the calculation unit 11 in time series. FIG. 5 is a diagram showing the data relayed when the gateway device 1 receives the data shown in FIG. 4 in chronological order.

  For example, as illustrated in FIG. 4, the arithmetic unit 11 receives received data V, received data W, received data X, and received data Y from the communication bus 2. The received data V, received data W, received data X, and received data Y are all received data having the same contents in the command area 42 and different contents in the parameter area 43. The calculation unit 11 sequentially receives the reception data V once, the reception data W four times, the reception data X twice, and the reception data Y once in order. As shown in FIG. 4, the arithmetic unit 11 receives the received data V at the time t1, the received data W at the time t2, the time t3, the time t4, and the time t5, and the time t6 and the time t7. Reception data X is received at each time point, and reception data Y is received at time point t8.

  For example, when the calculation unit 11 receives the reception data W at time t2, the content of the stored data is set in advance to be the same as the previous reception data V. That is, since the content of the stored data does not match the content of the received data W, the calculation unit 11 overwrites and updates the content of the stored data with the received data W based on the processing from step S12 to step S15. Thereafter, as illustrated in FIG. 5, the arithmetic unit 11 relays the received data W to the communication bus 3 based on the process of step S <b> 17 described above.

  At time t3, the calculation unit 11 increases the value of the number counter value N based on the processing from step S12 to step S15 because the content of the received data W received at that time matches the stored data. . Here, the count counter value N is 2, but since the threshold value Nth value 3 is not exceeded, the calculation unit 11 does not relay the received data W.

  Also at the time t4, the calculation unit 11 increases the value of the number counter value N in the same manner as the process at the time t3. Here, the count counter value N is 3, but since the threshold value Nth is not exceeded, the calculation unit 11 does not relay the received data W received at that time.

  On the other hand, when the calculation unit 11 increases the value of the number counter value N at the time t5, the value of the number counter N becomes 4. That is, since the count counter value N exceeds the threshold value Nth, the calculation unit 11 relays the received data W received at time t5 to the communication bus 3 based on the processing from step S14 to step S17.

  By the same processing as described above, at the time t6, the calculation unit 11 relays the received data X received at that time because the content has changed from the previous received data. At time t7, the reception data X having the same content as the previous reception data is received, and the count value N does not exceed the threshold value Nth, so that the reception data X is not relayed. Further, at time t8, the calculation unit 11 relays the received data Y received at that time because the content has changed from the previous received data.

  As described above, as shown in FIG. 5, the arithmetic unit 11 does not relay the received data at the time t3, time t4, and time t7 when the same received data as the previous time is received. Therefore, according to the gateway device 1, the amount of data traffic on the communication bus 3 can be reduced.

  On the other hand, the arithmetic unit 11 relays the received data at time t5 when the number of receptions is greater than the threshold value Nth even when the same received data as the previous time is received (see FIG. 5). That is, when the gateway device 1 continuously receives reception data having the same content over a long period of time, the gateway device 1 can periodically relay the reception data. Therefore, for example, even if the in-vehicle control device 31 connected to the communication bus 3 is a control device that changes the mode of operation to an abnormal mode when data reception is interrupted for a predetermined time, In addition, by relaying received data, it is possible to prevent the communication from being interrupted and to prevent unnecessary mode switching.

  Note that the calculation unit 11 may determine the contents of the command area 42 of the received data, and execute the processing of FIG. 3 for each piece of data having the same contents of the command area 42, that is, for each piece of data of the same type. . The calculation unit 11 may receive various data such as data indicating the engine speed and data indicating the temperature in the passenger compartment in a mixed state. In such a case, even if the same data is continuously received for a specific type of data, the process of stopping the relay for the specific type of data is not executed if another type of data is received in the meantime. There is a case. Therefore, the computing unit 11 can reduce the data relay amount more appropriately by determining the contents of the command area 42 of the received data and executing the processing of FIG. 3 for each type of data.

  Specifically, the calculation unit 11 individually updates the stored data for each type of received data indicated in the command area 42, such as data indicating the engine speed and data indicating the temperature in the passenger compartment. Then, the calculation unit 11 compares each received data with stored data that matches the contents of the command area 42. Here, when the content of the parameter area 43 of the received data does not match that of the stored data, the calculation unit 11 stops relaying only for the type of data until the number of receptions reaches the threshold value Nth.

(Second Embodiment)
In the first embodiment, the calculation unit 11 performs the process of relaying the reception data when the reception data having the same content is continuously received a predetermined number of times. However, the calculation unit 11 performs the relay process. If the relay is not performed for a predetermined time after executing the above, the received data may be relayed.

  The gateway device according to the second embodiment will be described below. The gateway device according to the second embodiment differs from the first embodiment in the processing of the calculation unit 11. The process of the calculating part 11 which concerns on 2nd Embodiment is demonstrated with reference to FIG. FIG. 6 is an example of a flowchart illustrating processing executed by the calculation unit 11 according to the second embodiment. Note that the configuration of the gateway device according to the second embodiment is the same as that of the gateway device 1 according to the first embodiment described above, and a description thereof will be omitted.

  Similar to the calculation unit 11 according to the first embodiment, the calculation unit 11 according to the second embodiment is supplied with power to the gateway device 1 by turning on the IG power source of the vehicle, for example. In this case, the processing of the flowchart shown in FIG. 6 is started. When the calculation part 11 starts the process of the flowchart shown in FIG. 6, first, the process of step S20 is executed.

  In step S20, the calculation unit 11 initializes the timer value T. The timer value T is a value indicating an elapsed time after the calculation unit 11 relays received data. In step S20, the calculation unit 11 sets the timer value T to an initial value. The initial value of the timer value T is set in advance to 0, for example. Note that the timer value T is stored in the storage unit 12, and is increased or decreased in the processing of steps S26 and S29 described later. When the process of step S20 is completed, the calculation unit 11 advances the process to step S21.

  In step S <b> 21, the calculation unit 11 determines whether data has been received. Since the process of this step S21 is the same as the process of the above-mentioned step S11, detailed description is abbreviate | omitted. If it is determined that the data has been received, the arithmetic unit 11 advances the process to step S22. On the other hand, when it is determined that the data is not received, the arithmetic unit 11 advances the process to step S28.

  In step S22, the computing unit 11 determines whether or not the received data is the same as the stored data. Since the process of this step S22 is the same as the process of the above-mentioned step S12, detailed description is abbreviate | omitted. If computing unit 11 determines that the received data is the same as the stored data, processing proceeds to step S24. On the other hand, when the arithmetic unit 11 determines that the received data is different from the stored data, the arithmetic unit 11 advances the process to step S25.

  In step S24, the computing unit 11 determines whether or not the timer value T is greater than the threshold value Tth. The threshold value Tth is an arbitrary constant stored in advance in the storage unit 12. The calculation unit 11 reads the value of the threshold value Tth from the storage unit 12 and compares the values of the timer value T and the threshold value Tth. If it is determined that the timer value T is greater than the threshold value Tth, the arithmetic unit 11 advances the process to step S26. On the other hand, when it is determined that the timer value T is equal to or less than the threshold value Tth, the arithmetic unit 11 advances the process to step S29.

  In step S25, the calculation unit 11 updates the stored data. Since the process of this step S25 is the same as the process of the said step S15, detailed description is abbreviate | omitted. When the process of step S25 is completed, the arithmetic unit 11 advances the process to step S26.

  In step S26, the calculation unit 11 resets the timer value T. Specifically, the calculation unit 11 returns the timer value T to the initial value and stores it in the storage unit 12. When the process of step S26 is completed, the arithmetic unit 11 advances the process to step S27.

  In step S27, the arithmetic unit 11 relays the stored data to the other bus. Since the process of this step S27 is the same as the process of the above-mentioned step S17, detailed description is abbreviate | omitted. When the process of step S27 is completed, the calculation unit 11 advances the process to step S28.

  In step S <b> 28, the calculation unit 11 determines whether an end process has been executed. Since the process of this step S28 is the same as the process of the above-mentioned step S18, detailed description is abbreviate | omitted. If it is determined that the termination process has not been executed, the arithmetic unit 11 advances the process to step S29. On the other hand, when it is determined that the end process has been executed, the arithmetic unit 11 ends the process of the flowchart of FIG.

  In step S29, the calculation unit 11 counts up the timer value T. Specifically, the arithmetic unit 11 increases the timer value T by a predetermined arbitrary value. When the process of step S29 is completed, the process returns to step S21.

  By the processing from step S21 to step S29, the timer value T is reset at the timing when the received data is relayed, and continuously increases until the timing.

  According to the processing from step S21 to step S29, when the received data has changed and when the timer value T is larger than the threshold value Tth when the same data as the previously received data is received, Relay received data. That is, when the reception unit having the same content is continuously received, the calculation unit 11 stops relaying the reception data until a predetermined time elapses. Therefore, the gateway device according to the second embodiment can reduce the amount of data traffic on the relay destination communication bus.

  Moreover, even if the calculation part 11 has received the reception data of the same content continuously, when the fixed time passes, the said reception data can be relayed. Therefore, for example, even if the vehicle control device connected to the communication bus of the relay destination is a control device that changes the mode of operation to an abnormal mode when data reception is interrupted for a predetermined time, By periodically relaying received data, communication interruption can be prevented and unnecessary mode switching can be prevented.

  Next, with reference to FIG. 4 and FIG. 7, how the gateway device according to the second embodiment relays received data will be described. FIG. 7 is a diagram illustrating data relayed by the gateway device according to the second embodiment that has received the data illustrated in FIG. 4. The following describes how the gateway device according to the second embodiment receives the received data shown in FIG. 4 and relays each received data. In FIG. 4, the calculation unit 11 receives each reception data at a constant time interval d from time t1 to time t8. In addition, the calculation unit 11 performs a process of adding d to the timer value T in step S29 described above. The threshold value Tth is set in advance to a time longer than 2d and shorter than 3d.

  At time t2, the calculation unit 11 updates the stored data with the received data W based on the processing from step S21 to step S25 described above. And the calculating part 11 relays the reception data W to the communication bus 3 based on the process of the above-mentioned step S27. Here, the calculating part 11 adds d to the timer value T based on the process of step S29, and sets the value of the timer value T to d.

  At time t3, the calculation unit 11 determines whether the timer value T is greater than the threshold Tth based on the processing from step S21 to step S24 because the content of the received data W received at that time matches the stored data. Judge whether or not. As described above, since the value of the timer value T is d and is equal to or less than the threshold value Tth, the calculation unit 11 does not relay the reception data W at the time point. And the calculating part 11 adds d to the timer value T based on the process of step S29, and makes the value of the timer value T 2d.

  Even at the time t4, the calculation unit 11 does not relay the received data W received at the time, similarly to the process at the time t3. In addition, the calculation unit 11 further adds d to the timer value T to set the timer value T to 3d.

  Since the value of the timer value T is larger than the threshold value Tth at time t5, the calculation unit 11 advances the process from step S24 to step S26, and sends the reception data W to the communication bus 3. Relay.

  By the same processing as described above, at the time t6, the calculation unit 11 relays the received data X received at that time because the content has changed from the previous received data. At time t7, reception data X having the same content as the previous reception data is received, and the timer value T does not exceed the threshold value Tth. Therefore, the reception data X is not relayed. Further, at time t8, the calculation unit 11 relays the received data Y received at that time because the content has changed from the previous received data.

  As described above, as illustrated in FIG. 7, the arithmetic unit 11 does not relay the received data at the time t3, time t4, and time t7 when the same received data as the previous time is received. Therefore, according to the second gateway device, the amount of data traffic on the communication bus 3 can be reduced.

  On the other hand, even if the calculation unit 11 receives the same reception data as the previous time, the calculation unit 11 relays the reception data at time t5 when the timer value T becomes larger than the threshold value Tth (see FIG. 5). That is, when the gateway device 1 continuously receives reception data having the same content over a long period of time, the gateway device 1 can periodically relay the reception data. Therefore, for example, even if the in-vehicle control device 31 connected to the communication bus 3 is a control device that changes the mode of operation to an abnormal mode when data reception is interrupted for a predetermined time, In addition, by relaying received data, it is possible to prevent the communication from being interrupted and to prevent unnecessary mode switching.

  In the description of FIGS. 4 and 7 described above, the calculation unit 11 has been described as an example in which each reception data is received at a constant time interval d. However, the time interval at which each reception data is received is not constant. Needless to say, the processing of FIG. 6 is applicable.

  In the above description, the calculation unit 11 itself counts the timer value T, that is, the elapsed time since relaying the received data. However, a timer counting unit such as a program or a device capable of measuring the time is separately provided. When prepared, the calculation unit 11 may measure the elapsed time after relaying the received data with reference to the measurement value of the timer count unit.

(Third embodiment)
The computing unit 11 may determine whether or not the received data is data to be relayed, and may execute the process of FIG. 3 only when the received data is data to be relayed. The gateway device according to the third embodiment will be described below. Note that the configuration of the gateway device according to the third embodiment is the same as that of the gateway device 1 according to the above-described first embodiment, and thus description thereof is omitted.

  Hereinafter, the process of the calculating part 11 which concerns on 3rd Embodiment is demonstrated with reference to FIG. FIG. 8 is an example of a flowchart illustrating processing executed by the calculation unit 11 according to the third embodiment. In the flowchart of FIG. 8, steps that perform the same processing as in the flowchart of FIG. 3 are given the same reference numerals, and detailed description thereof is omitted.

  If the calculation unit 11 according to the third embodiment determines that data has been received in the process of step S11, the process proceeds to step S31.

  In step S31, the calculation unit 11 determines whether the received data is data to be relayed. Specifically, the calculation unit 11 determines whether the received data is data to be relayed based on the contents of the command area 42 of the received data. The storage unit 12 stores in advance table data indicating a list of command codes of data to be relayed from the communication bus 2 to the communication bus 3. Then, the calculation unit 11 determines whether the content of the command area 42 of the received data matches any of the command codes indicated in the table data stored in the storage unit 12 in advance. The arithmetic unit 11 determines that the received data is data to be relayed when the content of the command area 42 of the received data matches any of the command codes indicated in the table data stored in the storage unit 12 in advance. The process proceeds to step S12. On the other hand, if the content of the command area 42 of the received data does not match any of the command codes indicated in the table data stored in the storage unit 12 in advance, it is determined that the received data is not data to be relayed, and the process is performed in step S18. Proceed to

  According to the above processing, when the received data is data that should not be relayed, it is not necessary to execute the processing from step S12 to step S17. Therefore, according to the gateway device according to the third embodiment, the processing amount of the calculation unit 11 can be reduced.

  Also in the second embodiment and the third embodiment, the calculation unit 11 determines the contents of the command area 42 of the received data, and for each piece of data in which the contents of the command area 42 are the same, that is, the same type. The processing of FIGS. 6 and 8 may be executed for each data.

  In the above embodiments, the gateway device 1 is mounted on a vehicle and an example of constructing an in-vehicle network has been described. However, the gateway device 1 is a network other than the in-vehicle network as long as it relays data between a plurality of communication lines. It can be applied to any communication network.

  In each of the above embodiments, the example in which the gateway device 1 is connected to two communication buses has been described. However, the gateway device 1 is connected to two or more communication buses and executes the above processing. It doesn't matter.

  In each of the above embodiments, the gateway device 1 relays data in the format shown in FIG. 2, but the format of data relayed by the gateway device 1 is not limited to the above. For example, the arithmetic unit 11 receives data in a format that does not have the parameter area 43, and relays the data depending on whether only the command area 42 matches the data part of the stored data in the storage unit 12. It may be determined whether or not. In addition, the calculation unit 11 may determine whether or not to relay the data depending on whether or not all parts of the received data match all the parts of the data stored in the storage unit 12. Absent.

  The gateway device according to the present invention is useful as a gateway device that can relay data from one communication bus to the other communication bus at an appropriate timing.

The block diagram which shows the structure of the vehicle-mounted network containing the gateway apparatus 1 which concerns on 1st Embodiment. The figure which shows an example of the format of the data output from the vehicle-mounted control apparatus which concerns on 1st Embodiment. An example of a flowchart showing processing executed by the calculation unit 11 according to the first embodiment The figure which showed the reception data which the gateway apparatus 1 which concerns on 1st Embodiment received in time series order The figure which showed the data relayed when the gateway apparatus 1 which concerns on 1st Embodiment received the data shown in FIG. 4 in time series order An example of a flowchart showing processing executed by the calculation unit 11 according to the second embodiment The figure which showed the data relayed when the gateway apparatus which concerns on 2nd Embodiment received the data shown in FIG. 4 in time series order An example of a flowchart showing processing executed by the calculation unit 11 according to the third embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gateway apparatus 2, 3 Communication bus 11 Calculation part 12 Storage part 21, 22, 23, 31, 32, 33 Vehicle-mounted control apparatus 41 Header area 42 Command area 43 Parameter area

Claims (6)

Is connected to two communication buses, the data received from the predetermined communication bus is either of the communication bus to a gateway device for relaying to the other communication bus,
A data comparison / determination unit that determines whether the received data and the received data previously received from the predetermined communication bus match each time reception data is received from the predetermined communication bus;
(A) When it is determined that the received data and the previously received data do not match, the received data is relayed to the other communication bus, and (b) the received data and the previously received received data are And when a predetermined condition is satisfied, the received data is relayed to the other communication bus, and (c) the received data and the previously received data match, and the condition A gateway device comprising: a relay unit that does not relay the received data when the above is not satisfied. A determination number counting means for counting the number of determinations continuously determined that the received data matches the received data received last time;
The relay means (a) relays the received data to the other communication bus when it is determined that the received data does not match the previously received data, and (d) the received data and the previous data When the received data matches and the number of determinations is greater than a predetermined threshold, the received data is relayed to the other communication bus, and (e) the received data and the previously received received data The gateway apparatus according to claim 1, wherein the received data is not relayed when they match and the number of times of determination is equal to or less than the threshold value. Timer means for measuring the elapsed time from the time when the relay means relayed,
The relay means (a) relays the received data to the other communication bus when it is determined that the received data and the previously received data do not match, and (f) the received data and the previous data If the received data matches the received data and the elapsed time is greater than a predetermined threshold, the received data is relayed to the other communication bus, and (g) the received data and the previously received received data are The gateway apparatus according to claim 1, wherein the received data is not relayed if they match and the elapsed time is less than or equal to the threshold value. The data comparison determination means includes
Storage means for storing the received data as storage data;
Stored data update means for overwriting and updating the stored data with the received data when the received data does not match the stored data;
The received data and the stored data are compared, and if the received data and the stored data match, it is determined that the received data and the previously received received data match, and the received data The stored data comparing means for determining that the received data and the previously received received data do not match when the stored data and the stored data do not match is provided. Gateway device. Further comprising data discriminating means for discriminating whether or not the received data is data that needs to be relayed to the other communication bus;
The data comparison / determination means determines whether or not the received data and the previously received data match only when the received data is data that needs to be relayed to the other communication bus. And
The gateway device according to claim 1, wherein the relay unit relays the received data only when the received data is data that needs to be relayed to the other communication bus. The communication bus is a network line that interconnects in-vehicle devices mounted on a vehicle,
The gateway device according to claim 1, wherein the gateway device is mounted on the vehicle.

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