JP2011235848A - Electronic control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic control device, capable of reducing a processing load as much as possible by delaying a transmission of the electronic control device as a reception object which processing load exceeds the predetermined value, and also capable of performing the transmission without delay when the transmission of the electronic control device as a reception object which processing load does not exceed the predetermined value.SOLUTION: An electronic control device stores a transmission timing adjustment value 1 in a transmission adjustment message (S406) when a communication load or a CPU load is higher than a threshold 1 (S402:Yes) and the threshold 2 or lower (S404:No) and stores a transmission timing adjustment value 2 in the transmission adjustment message (S408) when the communication load or CPU load is higher than the threshold 2 (S404:Yes). The transmission adjustment message generated in S406 or S408 is transmitted to a communication bus in the network. Additionally, the transmission timing adjustment value 1 is smaller than the transmission timing adjustment value 2. The electronic control device which receives the transmission adjustment message delays the transmission of the electronic control device as the reception object which transmits the transmission adjustment message.

Description

  The present invention relates to an electronic control device connected to a communication bus.

  2. Description of the Related Art Conventionally, a system in which a plurality of electronic control devices are connected to a communication bus and performs data processing in each electronic control device while transmitting / receiving data to / from each other is known, such as an in-vehicle network.

  In such a system, when the processing load of the own device, which is the electronic control device connected to the communication bus, is increasing, when data for receiving the own device is transmitted from another electronic control device, Processing of own device may be hindered.

  Therefore, in Patent Document 1, for example, when communication data is concentrated on a data relay device that relays communication data between communication buses, an empty frame indicating that the communication bus is in use is provided on at least one of the communication buses. An attempt is made to prevent data from being transmitted from another electronic control unit to the communication bus that has been transmitted by the data relay device and has transmitted the empty frame. Thus, by preventing data from being transmitted to the communication bus, the processing load on the data relay apparatus is reduced.

JP 2008-283386 A

  However, when an empty frame is transmitted to the communication bus, transmission from the electronic control unit connected to the communication bus to which the empty frame is transmitted is awaited. If transmission data is further generated while waiting for transmission, the transmission data is stored in the transmission buffer of the electronic control unit, so that the transmission data increases.

  When the transmission of the empty frame is completed and transmission becomes possible, the electronic control devices waiting for transmission attempt transmission all at once, so that the processing load of the data relay device increases again and the data relay device transmits the empty frame. I have to send it again. When such a state is repeated, there is a problem in that processing in the electronic control device connected to the communication bus is hindered.

  In this way, in a method of transmitting an empty frame or the like indicating that the communication bus is in use and delaying transmission from another electronic control device, data is transmitted to a device different from the device having an increased processing load. Even in the case of transmission, there is a problem that transmission is delayed.

  The present invention has been made in order to solve the above-described problem. The processing load is reduced as much as possible by delaying transmission in which an electronic control device whose processing load exceeds a predetermined value is received, and the processing load is equal to or lower than a predetermined value. It is an object of the present invention to provide an electronic control device capable of executing transmission with the electronic control device as a reception target without delay.

  According to the first to third aspects of the present invention, when the processing load of the own device that is the electronic control device connected to the communication bus exceeds a predetermined value, the own device is received by another device connected to the communication bus. A transmission adjustment message that delays the target transmission is transmitted to the communication bus.

  As a result, since transmission for the electronic control device whose processing load exceeds the predetermined value is awaited, the processing load of the electronic control device whose processing load exceeds the predetermined value can be prevented from further increasing. In addition, it is possible to prevent a failure in receiving data for which the own apparatus is to be received in a state where the processing load exceeds a predetermined value.

  In addition, since the electronic control device whose processing load is equal to or less than the predetermined value does not transmit the transmission adjustment message, it is not a target for delaying transmission. Therefore, if the communication bus is in a usable state, it can be executed without delaying transmission for an electronic control device whose processing load is a predetermined value or less. As a result, it is possible to prevent unnecessary transmission delays for electronic control devices having a processing load of a predetermined value or less.

  According to the second aspect of the present invention, when the processing load determination unit determines that the processing load of the own device has exceeded a predetermined value and has become equal to or less than the predetermined value, transmission to the other device as a reception target is performed. A transmission permission message to be permitted is transmitted to the communication bus.

As a result, when the processing load of the own device falls below the predetermined value from a state where the processing load exceeds the predetermined value, transmission of the own device as a reception target from another device can be quickly started.
According to the third to sixth aspects of the present invention, when a transmission adjustment message is received from another device, the transmission targeted for the other device that has transmitted the transmission adjustment message is delayed.

  As a result, since transmission for the electronic control device whose processing load exceeds the predetermined value is awaited, the processing load of the electronic control device whose processing load exceeds the predetermined value can be prevented from further increasing. In addition, since the processing load exceeds a predetermined value, it is possible to prevent the other device from failing to receive data intended for reception by the other device.

  In addition, since the electronic control device whose processing load is equal to or less than the predetermined value does not transmit the transmission adjustment message, it is not a target for delaying transmission. Therefore, if the communication bus is in a usable state, it can be executed without delaying transmission for an electronic control device whose processing load is a predetermined value or less. As a result, it is possible to prevent unnecessary transmission delays for electronic control devices having a processing load of a predetermined value or less.

  According to the fifth aspect of the present invention, when the transmission adjustment message is received from another device, the length of the delay time for delaying the transmission intended for the other device that has transmitted the transmission adjustment message is variably adjusted.

  In this way, the length of the delay time for delaying the transmission to be received by another device that has transmitted the transmission adjustment message is not adjusted to the same length, but is variably adjusted. Accordingly, the length of the delay time for delaying transmission can be set appropriately.

  According to the sixth aspect of the present invention, when a transmission adjustment message is received from another device, at least one of the priority of transmission data targeted for reception by the other device and the priority of the function of the own device with respect to the other device. On the basis of one of them, the length of the delay time for delaying the transmission to be received by another device is variably adjusted.

  As a result, for example, if the data has a high priority requiring urgent data, the data targeted for reception by another device that has transmitted the transmission adjustment message is transmitted with a delay time as short as possible. On the other hand, in the case of data with a low priority, the delay time is made longer than data with a higher priority than that, and data for receiving other devices is transmitted.

  Further, when the priority of the function of the own device is higher than that of the other device that has transmitted the transmission adjustment message, the data targeted for reception by the other device that has transmitted the transmission adjustment message is transmitted with a delay time as short as possible. . On the other hand, when the priority of the function of the own apparatus is lower than that of the other apparatus that has transmitted the transmission adjustment message, the delay time is set longer than that when the priority is high, and data for receiving the other apparatus is transmitted.

  As described above, based on at least one of the priority of the transmission data and the priority of the function of the own device with respect to the other device, the delay time for delaying the transmission to be received by the other device that has transmitted the transmission adjustment message. By setting the length to be variable, it is possible to reduce the processing load of the other device that has transmitted the transmission adjustment message as much as possible, and to prevent the processing of high-priority data from being delayed.

  The functions of the plurality of means provided in the present invention are realized by hardware resources whose functions are specified by the configuration itself, hardware resources whose functions are specified by a program, or a combination thereof. The functions of the plurality of means are not limited to those realized by hardware resources that are physically independent of each other.

The block diagram which shows the electronic control apparatus by this embodiment. The block diagram which shows the some electronic control apparatus connected to a communication bus. The time chart which shows the delay state of transmission. (A) is a transmission routine of a transmission adjustment message, (B) is a flowchart showing a transmission routine of a transmission permission message. FIG. 6A is a flowchart illustrating a transmission adjustment message reception routine, and FIG. 5B is a flowchart illustrating a transmission permission message reception routine.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an electronic control unit (ECU) 10 of the present embodiment.
(ECU 10)
The ECU 10 mainly includes a power supply circuit 12, an input / output circuit 14, a microcomputer (hereinafter also referred to as “microcomputer”) 20, and a communication driver 50. The ECU 10 is connected to a communication bus 200, 210 of an in-vehicle network such as a CAN (Controller Area Network), and transmits and receives data to and from other ECUs 10 connected to the communication bus 200, 210, while controlling a brake, Control the behavior of injectors, doors, etc.

The power supply circuit 12 supplies power supplied from the battery to the input / output circuit 14, the microcomputer 20, and the communication driver 50.
The input / output circuit 14 outputs signals output from the sensor 2, the switch 4, and the like to the microcomputer 20 and outputs a control signal output from the microcomputer 20 to the actuator 6.

  The microcomputer 20 includes a CPU 22, a memory 24, a load measurement unit 30, a transmission timing adjustment value calculation unit 40, a transmission timing readjustment unit 42, a communication controller (not shown), and the like.

  The CPU 22 detects the engine operating state based on the output signals of the sensor 2 and the switch 4 by executing the vehicle control program stored in the memory 24. Based on the detected engine operating state, the ECU 10 outputs a control signal for controlling the behavior of a control target such as a brake, an injector, and a door driven by the actuator 6 to the actuator 6.

  The ECU 10 transmits / receives data to / from other ECUs 10 as other devices via the communication buses 200 and 210 by the CPU 22 executing the communication program stored in the memory 24 (see FIG. 2). Vehicle control is executed in cooperation with the ECU 10.

  When the load measurement unit 30, the transmission timing adjustment value calculation unit 40, and the transmission timing readjustment unit 42 receive a transmission adjustment message that is transmitted according to the processing load of the ECU 10 and a transmission adjustment message from another ECU 10. The program module used by the CPU 22 when executing the transmission adjustment process is shown.

  The load measuring unit 30 includes a communication load measuring unit 32 and a CPU load measuring unit 34, and measures the processing load of the ECU 10. The communication load measuring unit 32 measures the communication load based on the amount of data received by the ECU 10 from the communication buses 200 and 210 via the communication driver 50. The CPU load measuring unit 34 measures the CPU load.

  When the communication load or the CPU load is larger than a predetermined value because the ECU 10 measured by the load measuring unit 30 is incapable of processing, the transmission timing adjustment value calculating unit 40 is automatically connected to other ECUs 10 connected to the communication buses 200 and 210. The transmission timing adjustment value is calculated according to the processing load as a delay time for delaying the transmission timing for which the ECU 10 as the device is a reception target.

  When the transmission timing adjustment value calculation unit 40 calculates a transmission timing adjustment value that delays transmission whose reception target is its own device, the microcomputer 20 transmits an ID (identifier) code for notifying that transmission of its own device is delayed. Then, the transmission timing adjustment value and the adjustment period indicating how long the transmission for which the own apparatus is to be received are delayed based on the transmission timing adjustment value are output to the communication driver 50 as a transmission adjustment message. The communication driver 50 converts the transmission adjustment message into a frame and transmits it to the communication buses 200 and 210.

  When the CPU timing or communication load measured by the other ECU 10 is greater than a predetermined value, the transmission timing readjustment unit 42 receives from the other ECU 10 a transmission adjustment message that delays transmission with the other ECU 10 as a reception target. In accordance with the transmission timing adjustment value stored in the transmission adjustment message, the priority of the transmission message to be received by the other ECU 10 that has transmitted the transmission adjustment message, the priority of the function of the own device with respect to the other ECU 10, and In consideration of the above, a transmission timing readjustment value for delaying the transmission targeted for reception by another ECU 10 that has transmitted the transmission adjustment message is calculated.

  The communication driver 50 outputs data received from the communication buses 200 and 210 to the microcomputer 20 and transmits communication data generated by the microcomputer 20 to the communication buses 200 and 210.

(Processing load)
When the communication load or CPU load of its own device (also referred to as its own node) exceeds a predetermined threshold as a predetermined value set in advance, ECU 10 determines that its processing load has exceeded a predetermined value.

  The communication load is measured based on the amount of data per unit time of transmission data that is received by the device itself. The larger the amount of data received per unit time, the greater the communication load.

The CPU load is measured based on the ratio of the operating time during which the CPU 22 is operating per unit time. It is determined that the larger the operation time ratio, the greater the CPU load.
(Transmission adjustment processing)
Next, as shown in FIGS. 2 and 3, in a network in which ECU # 1 (own node), ECU # 2 (node A), and ECU # 3 (node B) are connected to communication buses 200 and 210, A transmission message adjustment process when the processing load of ECU # 1 exceeds a predetermined value will be described.

  When the processing load exceeds a predetermined value, ECU # 1 (own node) transmits a transmission adjustment message (MSG) for delaying transmission for receiving the own node to communication buses 200 and 210 as shown in FIG. To do. In the transmission adjustment message, a transmission timing adjustment value for delaying transmission with the ECU # 1 as a reception target and an adjustment period indicating when transmission is delayed based on the transmission timing adjustment value are set as data.

  When the ECU # 2 and the ECU # 3 receive the transmission adjustment message from the ECU # 1, the ECU # 2 and the ECU # 3 transmit the transmission data 100 and 110 that are scheduled to be transmitted unless the transmission adjustment message is received, with a transmission timing delayed. That is, the time intervals 102 and 112 at which the ECU # 2 and the ECU # 3 transmit the data for which the ECU # 1 is to be received are longer after receiving the transmission adjustment message than before receiving them.

  The degree to which ECU # 2 and ECU # 3 delay the transmission timing is adjusted by the adjustment value set in each ECU 10 according to the transmission timing adjustment value stored in the transmission adjustment message, and transmitted by ECU # 2 and ECU # 3. Is set variably based on the priority of the data to be performed and the priority of the function of each ECU set among ECU # 1, ECU # 2, and ECU # 3.

For example, the transmission timing is delayed as the transmission timing adjustment value set in the transmission adjustment message is larger.
In addition, even if ECU # 1 transmits a transmission adjustment message, if a brake message that needs to be urgently applied is transmitted from ECU # 2 to ECU # 1, ECU # 2 minimizes the delay in transmission timing as much as possible. Then, a brake message for receiving the ECU # 1 is transmitted.

Thereby, even if the processing load of the own node is large, ECU # 1 can receive a message with a high priority requiring urgentness as soon as possible, and can execute an appropriate brake operation.
On the other hand, when the priority of data for which ECU # 1 is received from ECU # 3 is low, the influence on vehicle control is small even if the transmission interval is increased.

  Even if ECU # 1 transmits the transmission adjustment message, if the processing load of ECU # 2 and ECU # 3 is equal to or lower than a predetermined value, it is necessary to delay transmission for receiving ECU # 2 or ECU # 3. Therefore, transmission with ECU # 2 or ECU # 3 as a reception target can be executed when communication buses 200 and 210 are free.

When the adjustment period ends, ECU # 2 and ECU # 3 start transmission with ECU # 1 as a reception target if communication buses 200 and 210 are free.
If ECU # 1 and ECU # 3 are waiting for transmission for which ECU # 1 is to be received and the processing load on ECU # 1 falls below a predetermined value, ECU # 1 sends a transmission permission message to communication bus 200. , 210 may be transmitted. When the ECU # 2 and the ECU # 3 receive the transmission permission message from the ECU # 1, the ECU # 2 and the ECU # 3 cancel the transmission adjustment process for delaying the transmission timing even during the adjustment period for delaying the transmission targeted for the ECU # 1. When the communication buses 200 and 210 are vacant, transmission with the ECU # 1 as a reception target is executed.

  Also, instead of delaying the transmission timing for ECU # 1 and setting the transmission timing adjustment value and adjustment period in the transmission adjustment message, ECU # 1 only adjusts the transmission delay for its own device. The notification of the transmission adjustment process may be notified to other ECUs 10 by transmitting a message to the communication bus 200 and 210 when the processing load becomes a predetermined value or less.

(Transmission adjustment processing routine)
FIG. 4 shows a flowchart of a transmission adjustment processing routine on the transmission adjustment message transmission side, and FIG. 5 shows a flowchart of a transmission adjustment processing routine on the reception side of the transmission adjustment message. The routine shown in FIG. 4 is executed at predetermined time intervals, and the routine shown in FIG. 5 is executed when a transmission adjustment message is received. 4 and 5, “S” represents a step.

(Sender)
In the routine of FIG. 4A, first, the ECU 10 measures the communication load and the CPU load (S400), and determines whether the communication load or the CPU load is higher than the corresponding threshold value 1 (S402). ).

  When the communication load or the CPU load is equal to or less than the threshold 1 (S402: No), the ECU 10 ends this routine. When the communication load or the CPU load is higher than the threshold 1 (S402: Yes), the ECU 10 determines whether or not the communication load or the CPU load exceeds the threshold 2 (S404). Note that threshold value 1 <threshold value 2.

  When the communication load or the CPU load is equal to or less than the threshold value 2 (S404: No), the ECU 10 stores the transmission timing adjustment value 1 and the adjustment period in the transmission adjustment message (S406), and ends this routine. The transmission adjustment message generated in S406 is transmitted to the communication buses 200 and 210 by the communication driver 50.

  When the communication load or the CPU load is higher than the threshold 2 (S404: Yes), the ECU 10 stores the transmission timing adjustment value 2 and the adjustment period in the transmission adjustment message (S408), and ends this routine. The transmission adjustment message generated in S408 is transmitted to the communication buses 200 and 210 by the communication driver 50. Transmission timing adjustment value 1 <transmission timing adjustment value 2 is satisfied.

  In this way, the ECU 10 whose processing load exceeds the predetermined value increases the transmission timing adjustment value and stores it in the transmission adjustment message as the processing load increases. Therefore, the ECU 10 that has received the transmission adjustment message receives the transmission adjustment message. A delay time for delaying transmission can be set in accordance with the transmitted processing load of the ECU 10. That is, the delay time is lengthened when the processing load is large, and the delay time is shortened when the processing load is small.

  Next, in the routine of FIG. 4B, the ECU 10 determines whether or not the communication load or CPU load has become higher than the threshold value 1 or less than the threshold value 1 (S420). If it is higher than the threshold 1 (S420: No), this routine is terminated.

  When the communication load and the CPU load are equal to or less than the threshold value 1 (S420: Yes), the ECU 10 transmits a transmission permission message from the communication driver 50 to the communication buses 200 and 210, and ends this routine.

(Receiver)
In the routine of FIG. 5A, first, the ECU 10 receives a transmission adjustment message (S430), and determines whether or not the transmission timing adjustment value stored in the transmission adjustment message exceeds the threshold A (S432). ).

  When the transmission timing adjustment value is equal to or less than the threshold value A (S432: No), the ECU 10 prioritizes the function of the own node, the priority of the data whose reception target is the ECU 10 that has transmitted the transmission adjustment message, and the transmission timing adjustment value. Is multiplied by the adjustment value A set in advance in each ECU 10 when the value is equal to or less than the threshold A, the transmission timing for the ECU 10 that has transmitted the transmission adjustment message is readjusted (S434), and this routine is terminated. To do.

  The priority of the function and transmission data is set to a smaller value as the priority is higher. Therefore, the higher the priority of the function and the transmission data, the shorter the transmission timing readjustment value calculated for delaying the transmission whose reception target is the ECU 10 that has transmitted the transmission adjustment message.

  When the transmission timing adjustment value exceeds the threshold A (S432: Yes), the ECU 10 determines whether or not the transmission timing adjustment value exceeds the threshold B (S436). Note that threshold A <threshold B.

  When the transmission timing adjustment value is equal to or less than the threshold value B (S436: No), the ECU 10 prioritizes the function of the own node, the priority of the data whose reception target is the ECU 10 that has transmitted the transmission adjustment message, and the transmission timing adjustment value. When the threshold value A exceeds the threshold value A but is equal to or less than the threshold value B, it is multiplied by the adjustment value B preset in each ECU 10 to readjust the transmission timing for the ECU 10 that has transmitted the transmission adjustment message as the reception target ( S438), this routine is finished. The adjustment value A <the adjustment value B.

  When the transmission timing adjustment value exceeds the threshold B (S436: Yes), the ECU 10 determines the priority of the function of the own node, the priority of the data whose reception target is the ECU 10 that has transmitted the transmission adjustment message, and the transmission timing. When the adjustment value exceeds the threshold value B, it is multiplied by the adjustment value C set in advance by each ECU 10, and the transmission timing for receiving the ECU 10 that has transmitted the transmission adjustment message is readjusted (S440), This routine ends. Note that adjustment value A <adjustment value B and <adjustment value C.

  Thus, the transmission timing readjustment value is variably set according to the transmission timing adjustment value stored in the transmission adjustment message. The transmission timing adjustment value increases as the transmission timing adjustment value increases, the lower the priority of the function for the ECU 10 that has transmitted the transmission adjustment message, and the lower the priority of the data to be received by the ECU 10 that has transmitted the transmission adjustment message. The readjustment value becomes longer.

In the calculation formulas of S434 and S438, the transmission timing readjustment value may be calculated by replacing the adjustment values A and B with the threshold values A and B.
Next, in the routine of FIG. 5B, the ECU 10 determines whether or not a transmission permission message has been received (S450), and when the transmission permission message has not been received (S450: No), this routine is executed. finish.

  When the transmission permission message is received (S450: Yes), the ECU 10 cancels the transmission adjustment process for receiving the ECU 10 that has transmitted the transmission adjustment message even during the adjustment period (S452), and ends this routine. To do. Thereby, when the communication buses 200 and 210 are vacant, the ECU 10 can transmit data for which the ECU 10 that has transmitted the transmission adjustment message is a reception target.

  According to the present embodiment described above, when the processing load exceeds a predetermined value, the ECU 10 transmits a transmission adjustment message to the communication buses 200 and 210 so as to delay the transmission for which the own device is to be received. As a result, since the transmission for which the ECU 10 whose processing load exceeds the predetermined value is received is waited for, the processing load of the ECU 10 whose processing load exceeds the predetermined value can be prevented from increasing further. In addition, it prevents data that is targeted for reception from the device itself when the processing load exceeds a predetermined value, so that data is transmitted when the processing load exceeds the predetermined value, and reception fails. Can be prevented.

  Moreover, since ECU10 whose processing load is below a predetermined value does not transmit a transmission adjustment message, it is not a target for delaying transmission. Therefore, if the communication buses 200 and 210 are in a usable state, transmission for which the ECU 10 whose processing load is equal to or less than the predetermined threshold can be received can be executed without delay. As a result, it is possible to prevent unnecessary transmission delays for the ECU 10 whose processing load is a predetermined value or less.

In the above embodiment, the ECU 10 corresponds to the electronic control device of the present invention, functions as a communication unit, a load determination unit, and a communication adjustment unit, and the communication driver 50 functions as a communication unit.
4A corresponds to the function executed by the load determination unit of the present invention, and the processes of S406 and S408 correspond to the function executed by the communication adjustment unit of the present invention. The process of S420 and S422 in (B) of 4 corresponds to the function executed by the communication adjusting means of the present invention, and the process of S422 corresponds to the function executed by the communication means of the present invention.

5A corresponds to the function executed by the communication unit of the present invention, and the processes of S432 to S440 correspond to the function executed by the communication adjustment unit of the present invention.
[Other Embodiments]
In the above-described embodiment, when a transmission adjustment message transmitted by another ECU 10 is received, the priority of transmission data targeted for reception by the ECU 10 that has transmitted the transmission adjustment message, and the function of the own device with respect to the ECU 10 that has transmitted the transmission adjustment message. Based on the priority and the adjustment value preset in each ECU 10 according to the transmission timing adjustment value stored in the transmission adjustment message, the transmission delay time for the ECU 10 that has transmitted the transmission adjustment message as a reception target The transmission timing readjustment value was variably calculated.

  On the other hand, the transmission timing adjustment value stored in the transmission adjustment message is used as the reception object for the ECU 10 that has transmitted the transmission adjustment message as it is without considering the priority of the transmission data and the function priority of the own device. It is good also as delay time of.

  Further, the transmission timing adjustment value may not be stored in the transmission adjustment message, and the ECU 10 that has received the transmission adjustment message may use a fixed transmission timing readjustment value. The transmission timing readjustment value may be variably set based on the priority.

  Moreover, in the said embodiment, the load measurement part 30 is comprised by both the measurement parts of the communication load measurement part 32 and the CPU load measurement part 34, and both the load of a communication load and CPU load is measured as processing load of ECU10. . On the other hand, the load measuring unit 30 may be configured with either the communication load measuring unit 32 or the CPU load measuring unit 34, and either the communication load or the CPU load may be measured as the processing load of the ECU 10.

  In the above embodiment, the event-driven CAN is described as an example of the in-vehicle network. However, the present invention may be applied to a time-driven FlexRay as the in-vehicle network. In the time-driven method, the transmission timing is set in advance for each ECU, but when an ECU whose processing load exceeds a predetermined value transmits a transmission adjustment message that delays transmission for receiving the device itself, the other ECUs The transmission adjustment message can be sent for the transmission to be received by the ECU that has transmitted the message.

  In the above embodiment, one CPU 22 executes vehicle control, load measurement, and transmission timing adjustment. However, vehicle control, load measurement, and transmission timing adjustment may be executed by individual CPUs.

  In the above embodiment, the functions of the communication means, the load determination means, and the communication adjustment means are realized by the ECU 10 whose functions are specified by the control program. On the other hand, at least some of the functions of the plurality of means may be realized by hardware whose functions are specified by the circuit configuration itself.

  As described above, the present invention is not limited to the above-described embodiment, and can be applied to various embodiments without departing from the gist thereof.

10: ECU (electronic control device, communication means, overhead view determination means, communication adjustment means), 50: communication driver (communication means), 200, 210: communication bus

Claims (6)

In an electronic control device connected to a communication bus,
Communication means for communicating with another device which is the other electronic control device via the communication bus;
Load determination means for determining whether or not the processing load of its own device that is the electronic control device exceeds a predetermined value;
When the load determination unit determines that the processing load exceeds the predetermined value, the communication unit transmits a transmission adjustment message for delaying transmission to the other device as a reception target to the communication bus. Communication adjustment means;
An electronic control device comprising:   When the load determination unit determines that the processing load has exceeded the predetermined value and has become the predetermined value or less after the processing load exceeds the predetermined value, the communication adjustment unit permits the other device to transmit the target device as a reception target. 2. The electronic control apparatus according to claim 1, wherein a transmission permission message is transmitted to the communication bus by the communication unit.   2. The communication adjustment unit, when the communication unit receives the transmission adjustment message from the other device, delays transmission for the other device that has transmitted the transmission adjustment message as a reception target. 2. The electronic control device according to 2. In an electronic control device connected to a communication bus,
Communication means for communicating with another device which is the other electronic control device via the communication bus;
When the communication unit receives from the other device a transmission adjustment message that delays the transmission intended for the other device, a communication adjustment unit that delays the transmission intended for the other device that has transmitted the transmission adjustment message;
An electronic control device comprising:   When the communication unit receives the transmission adjustment message from the other device, the communication adjustment unit variably adjusts the length of a delay time for delaying the transmission to be received by the other device that has transmitted the transmission adjustment message. The electronic control device according to claim 3, wherein the electronic control device is an electronic control device.   The communication adjustment means, when the communication means receives the transmission adjustment message from the other apparatus, the priority of transmission data to be received by the other apparatus and the priority of the function of the own apparatus with respect to the other apparatus 6. The electronic control device according to claim 5, wherein the length of the delay time is variably adjusted based on at least one of the above.

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