COMMUNICATION SYSTEM, ELECTRONIC CONTROL DEVICE AND MANAGEMENT DEVICE

A communication system includes a plurality of electronic control devices connected to be capable of transmitting and receiving a communication frame. The electronic control devices includes a power supply switching device configured to receive a power supply from a power source via a power supply switching section and a management device connected to the electronic control devices to be capable of transmitting and receiving a communication frame, and is configured to control an operation of one or a plurality of power supply switching sections. At least one of the electronic control devices includes a frame generation section configured to generate a management frame that is a communication frame and a frame transmission section configured to transmit the management frame.

CROSS REFERENCE TO RELATED APPLICATION

This application is based on Japanese Patent Application No. 2023-166035 filed on Sep. 27, 2023 and Japanese Patent Application No. 2024-129826 filed on Aug. 6, 2024, the disclosures of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a communication system including a plurality of electronic control devices.

BACKGROUND

A related art discloses an in-vehicle network system that includes a power source relay for switching individually on and off a power source of each of a plurality of electronic control devices, determines a control content for switching the power source of a specific electronic control device between an on state and an off state in the specific electronic control device corresponding to a scene which is determined based on a situation of the vehicle, and switches the on state and the off state of the power source to supply an electric power to the specific electronic control device using the power source relay.

SUMMARY

A communication system includes a plurality of electronic control devices connected to be capable of transmitting and receiving a communication frame. The electronic control devices includes a power supply switching device configured to receive a power supply from a power source via a power supply switching section and a management device connected to the electronic control devices to be capable of transmitting and receiving a communication frame, and is configured to control an operation of one or a plurality of power supply switching sections. At least one of the electronic control devices includes a frame generation section configured to generate a management frame that is a communication frame and a frame transmission section configured to transmit the management frame.

DETAILED DESCRIPTION

As a result of detailed studies by the inventors, the following difficulties have been found. In the in-vehicle network system described in a related art, all the electronic control devices connected to the management device are supplied with power from a power source via relays. Therefore, in the technology described in the related art, in a communication system in which an electronic control device connected to a relay and an electronic control device not connected to the relay are mixed, activation of a plurality of electronic control devices cannot be managed individually.

The present disclosure provides a technique to individually manage activation of a plurality of electronic control devices in a communication system including the plurality of electronic control devices.

According to one aspect of the present disclosure, a communication system including a plurality of electronic control devices connected to be capable of transmitting and receiving a communication frame is provided. The plurality of electronic control devices includes a power supply switching device and a management device. The power supply switching device is configured to receive a power supply from a power source via a power supply switching section configured to switch between a conduction state in which a power supply path is conducted and a cutoff state in which the power supply path is cut off. The management device is connected to the plurality of electronic control devices to be capable of transmitting and receiving a communication frame, and is configured to control an operation of one or a plurality of power supply switching sections. At least one of the plurality of electronic control devices includes a frame generation section and a frame transmission section. The frame generation section is configured to, when determining provision of a preset service based on a detected event, generate a management frame that is a communication frame including one or a plurality of pieces of switching information indicating whether to bring each of the one or the plurality of the power supply switching sections into the conduction state and one or a plurality of pieces of activation information indicating whether to activate an electronic control device that is not connected to the power supply switching section as a continuous power supply device for each of one or a plurality of the continuous power supply devices. The frame transmission section configured to transmit the management frame. The management device includes a power supply control section configured to bring each of the one or the plurality of the power supply switching sections into either the conduction state or the cutoff state based on the management frame.

In the communication system of the present disclosure configured as described above, the management device can bring one or the plurality of power supply switching sections into the conduction state or the cutoff state based on one or the plurality of pieces of switching information included in the management frame. Furthermore, in the communication system of the present disclosure, the management device can instruct one or a plurality of continuous power supply devices whether to activate based on one or a plurality of pieces of activation information included in the management frame. Therefore, in the communication system of the present disclosure, in a case where the electronic control device connected to the power supply switching section and the electronic control device not connected to the power supply switching section are mixed, the activation of the plurality of electronic control devices can be managed individually.

According to one aspect of the present disclosure, a communication system including a plurality of electronic control devices connected to be capable of transmitting and receiving a communication frame is provided.

The plurality of electronic control devices includes: a power supply switching device that receives a power supply from a power source via a power supply switching section configured to switch between a conduction state in which a power supply path is conducted and a cutoff state in which the power supply path is cut off, and a management device that is connected to the plurality of electronic control devices to be capable of transmitting and receiving a communication frame, and is configured to control an operation of one or a plurality of power supply switching sections. The management device includes a power supply control section configured to bring each of the one or the plurality of the power supply switching sections into either the conduction state or the cutoff state based on a management frame when receiving the management frame that is the communication frame including one or a plurality of pieces of switching information indicating whether to bring each of the one or the plurality of the power supply switching sections into the conduction state and one or a plurality of pieces of activation information indicating whether to activate an electronic control device that is not connected to the power supply switching section as a continuous power supply device for each of one or a plurality of continuous power supply devices.

In the communication system of the present disclosure configured as described above, the management device can bring one or the plurality of power supply switching sections into the conduction state or the cutoff state based on one or the plurality of pieces of switching information included in the management frame. Furthermore, in the communication system of the present disclosure, the management device can instruct one or a plurality of continuous power supply devices whether to activate based on one or a plurality of pieces of activation information included in the management frame. Therefore, in the communication system of the present disclosure, in a case where the electronic control device connected to the power supply switching section and the electronic control device not connected to the power supply switching section are mixed, the activation of the plurality of electronic control devices can be managed individually.

According to one aspect of the present disclosure, an electronic control device included in a communication system including one or a plurality of power supply switching sections configured to switch between a conduction state in which a power supply path is conducted from a power source to a power supply switching device and a cutoff state in which the power supply path is cut off is provided. The electronic control device includes: a frame generation section configured to, when determining a provision of a preset service based on a detected event, generate a management frame that is the communication frame including one or a plurality of pieces of switching information indicating whether to bring each of the one or the plurality of the power supply switching sections into the conduction state and one or a plurality of pieces of activation information indicating whether to activate one or a plurality of continuous power supply devices not connected to the power supply switching section, and a frame transmission section configured to transmit the management frame.

According to one aspect of the present disclosure, a management device connected to be capable of transmitting and receiving a communication frame with a plurality of electronic control devices and configured to control an operation of one or a plurality of power supply switching sections configured to switch between a conduction state in which a power supply path from a power supply to a power supply switching device is conducted and a cutoff state in which the power supply path is cut off is provided. The management device includes a power supply control section configured to receive a management frame that is the communication frame including one or a plurality of pieces of switching information indicating whether to bring each of the one or the plurality of the power supply switching sections into the conduction state and one or a plurality of pieces of activation information indicating whether to activate an electronic control device that is not connected to the power supply switching section as a continuous power supply device for each of one or a plurality of the continuous power supply devices, and to bring each of the one or the plurality of the power supply switching sections into either the conduction state or the cutoff state based on the management frame when receiving the management frame.

The management device of the present disclosure is a device used in the communication system of the present disclosure and can achieve the same effects as the communication system of the present disclosure.

The communication system1of the present embodiment is mounted in a vehicle, and includes a master ECU2, slave ECUs3,4,5, and6, and a battery7, as shown inFIG.1. The ECU is an abbreviation for an electronic control unit.

The master ECU2and the slave ECUs3,4, and5are connected to each other via a communication bus8so as to be capable of data communication. The master ECU2and the slave ECU6are connected to each other via a communication bus9so as to be capable of data communication.

The battery7supplies electric power to various parts of the vehicle at a DC (direct current) battery voltage (for example, 12V). The master ECU2and the slave ECUs3to6operate by receiving the electric power from the battery7.

The master ECU2includes a control section21, CAN communication units22,23, a storage section24, and relays25,26. The CAN is an abbreviation for Controller Area Network. The communication protocol of the communication system1is not limited to CAN.

The control section21is an electronic control device mainly including a microcomputer with a CPU31, a ROM32, a RAM33, and the like. Various functions of the microcomputer are implemented by the CPU31executing programs stored in a non-transitory tangible storage medium. In this example, the ROM32corresponds to the non-transitory tangible storage medium in which a program is stored. By executing the program, the method corresponding to the program is performed. A part or all of the functions to be executed by the CPU31may be configured in hardware by one or multiple ICs or the like. Alternatively, the number of the microcomputers constituting the control section21may be one or more.

The CAN communication section22communicates with the slave ECUs3,4,5connected to the communication bus8by transmitting and receiving a communication frame based on the CAN communication protocol. The CAN communication section23performs communication with the slave ECU6connected to the communication bus9by transmitting and receiving a communication frame based on the CAN communication protocol. Hereinafter, the CAN communication frame will be referred to as a CAN frame.

The storage section24is a storage device for storing various pieces of data. The storage section24stores a management table35and a diagnostic mask table36to be described later. The relay25is disposed on a power supply path10between the battery7and the slave ECU3. The relay26is disposed on a power supply path12between the battery7and the slave ECU5. The slave ECU4receives a power supply from the battery7via a power supply path11.

The relay25is configured to switch between a conduction state in which the power supply path10is conducted and a cutoff state in which the power supply path10is cut off in accordance with a command from the control section21. The relay26is configured to switch between a conduction state in which the power supply path12is conducted and a cutoff state in which the power supply path12is cut off in accordance with a command from the control section21. Hereinafter, the conduction state is also referred to as an on state, and the cutoff state is also referred to as an off state.

The slave ECUs3to6include a control section41, a CAN communication section42, and a storage section43. The control section41is an electronic control device mainly including a microcomputer comprising a CPU51, a ROM52, a RAM53, and the like. Various functions of the microcomputer are implemented by the CPU51executing a program stored in a non-transitory tangible recording medium. In this example, the ROM52corresponds to a non-transitory tangible recording medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU51may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section41may be one or more.

The CAN communication section42of the slave ECUs3to5performs communication with communication devices (i.e., the master ECU2and the slave ECUs3to5) connected to the communication bus8based on the CAN communication protocol.

The CAN communication section42of the slave ECU6communicates with a communication device (that is, the master ECU2) connected to the communication bus9based on a CAN communication protocol. The storage section43is a storage device for storing various pieces of data. The storage section43stores a management table55and a diagnostic mask table56to be described later.

The CAN frame includes a start of frame, an arbitration field, a control field, a data field, a CRC field, an ACK field, and an end of frame. The arbitration field includes an 11-bit or 29-bit identifier (i.e., ID) and a 1-bit RTR bit.

The 11-bit identifier used in CAN communication is referred to as a CAN ID. The CAN ID is preset based on the content of data included in the CAN frame, the transmission source of the CAN frame, the transmission destination of the CAN frame, and the like.

The data field is a payload including first data, second data, third data, fourth data, fifth data, sixth data, seventh data, and eighth data each of which has 8 bits (i.e., one byte).

The master ECU2and the slave ECUs3,4,5, and6are configured to switch between a wake-up state (i.e., the activation state) and a sleep state (i.e., the dormancy state). The wake-up state is a normal operation state in which a function assigned to the ECU can be used without restriction. The sleep state is a low power consumption operation state in which available functions are restricted.

In the communication system1, an NM frame, which is a CAN frame containing switching information and activation information, is used to switch the relays25and26to an on state or an off state and to switch the slave ECUs4and6not connected to the relays25and26to a wake-up state or a sleep state. NM is an abbreviation for Network Management.

The switching information indicates whether to turn on the relays25and26. The activation information indicates whether to bring the slave ECUs4and6into the wake-up state. The switching information and the activation information are set as illustrated inFIG.2, for example. DLC stands for Data Length Code, and is a region representing the size of a data field in a CAN frame in byte units. That is, the switching information and the activation information are stored in the data field of the CAN frame. Here, in order to simplify the description, a case where DLC is 1 byte (that is, 8 bits) will be described.

The switching information of the relay25, the switching information of the relay26, the activation information of the slave ECU4, and the activation information of the slave ECU6are allocated to respective bits of 8-bit data. In the NM frame illustrated inFIG.2, the switching information of the relay25is allocated to the first highest bit of the first data, the activation information of the slave ECU4is allocated to the second highest bit of the first data, the switching information of the relay26is allocated to the third highest bit of the first data, and the activation information of the slave ECU6is allocated to the fourth highest bit of the first data.

Then, in the NM frame illustrated inFIG.2, since 1 is set in the first highest bit of the first data, the NM frame illustrated inFIG.2instructs the relay25to be turned on.

In addition, in the NM frame illustrated inFIG.2, since 0 is set in the second highest bit of the first data, the NM frame illustrated inFIG.2instructs the slave ECU4to be in the sleep state.

In addition, in the NM frame illustrated inFIG.2, since 0 is set to the third highest bit of the first data, the NM frame illustrated inFIG.2instructs the relay26to be turned off. Further, in the NM frame illustrated inFIG.2, since 1 is set to the fourth highest bit of the first data, the NM frame illustrated inFIG.2instructs the slave ECU6to be in the wake-up state.

The management tables35and55illustrated inFIG.1set a correspondence relationship between a service, and switching information and activation information for each of a plurality of services provided to an occupant of the vehicle using the master ECU2and the slave ECUs3to6as illustrated inFIG.4. Note that the management tables35and55of the master ECU2and the slave ECUs3to6may not store switching information and activation information for a service for which the subject device cannot determine the establishment of the service start condition based on an event detected by the subject device.

The management tables35and55specify, for example, for the first service, that the relay25is turned on as the switching information of the relay25, that the relay26is turned off as the switching information of the relay26, that the slave ECU4is brought into a wake-up state as the activation information of the slave ECU4, and that the slave ECU6is brought into a sleep state as the activation information of the slave ECU6.

The management tables35and55specify, for example, for the second service, that the relay25is turned off as the switching information of the relay25, that the relay26is turned on as the switching information of the relay26, that the slave ECU4is brought into a sleep state as the activation information of the slave ECU4, and that the slave ECU6is brought into a wake-up state as the activation information of the slave ECU6.

By rewriting the management tables35and55, it is possible to update the switching information and the activation information included in the NM frames transmitted by the master ECU2and the slave ECUs3to6.

The management tables35and55may include activation information of the slave ECUs3and5that receive a power supply from the battery7via the relays25and26. The diagnostic mask tables36and56illustrated inFIG.1set a correspondence relationship between a slave ECU (hereinafter, a cutoff ECU) whose power supply via a relay is cut off and a slave ECU (hereinafter, a sleep ECU) which is brought into a sleep state and a CAN ID (hereinafter, a non-reception frame ID) of a CAN frame which is not received, for each service as illustrated inFIG.4.

Therefore, in the diagnostic mask tables36and56, one or a plurality of combinations of the cutoff ECU and the non-reception frame ID, and one or a plurality of combinations of the sleep ECU and the non-reception frame ID are set for one service.

The diagnostic mask tables36and56specify, for example, for the first service, a combination of the slave ECU5and the first CAN ID and a combination of the slave ECU6and the second CAN ID.

The diagnostic mask tables36and56specify, for example, for the second service, a combination of the slave ECU3and the third CAN ID and a combination of the slave ECU4and the fourth CAN ID.

Therefore, when detecting that the start condition of the service is satisfied, the master ECU2and the slave ECUs3to6extract the switching information and the activation information corresponding to the corresponding service from the management tables35and55, and generate and transmit the NM frame including the extracted switching information and activation information. Further, the master ECU2and the slave ECUs3to6extract a combination of the cutoff ECU or the sleep ECU corresponding to the corresponding service and the non-reception frame ID from the diagnostic mask tables36and56to transmit the extracted combination as diagnostic mask information.

In a state where a plurality of NM frames corresponding to a plurality of services are being transmitted, the relay is turned on by the OR (logical sum) of the switching information at the receiving ECU of the NM frame, and the relay is turned off by the AND (logical product) of the switching information. On the other hand, when the same ECU generates NM frames corresponding to a plurality of services, the ECU may generate and transmit a single NM frame corresponding to the plurality of services, using OR for the switching information to turn on the relay and AND for the switching information to turn off the relay.

As a result, even if the master ECU2and the slave ECUs3to6determine that communication with the cutoff ECU and the sleep ECU has been interrupted, it is possible to avoid regarding it as abnormal.

By rewriting the diagnostic mask tables36and56, it is possible to update the diagnostic mask information transmitted by the master ECU2and the slave ECUs3to6. Next, a procedure of a management process executed by the control section21of the master ECU2will be described. The management process is a process repeatedly executed during activation of the master ECU2.

When the management process is executed, in S10, the CPU31of the control section21determines whether an NM frame has been received as illustrated inFIG.3. Here, in a case where the NM frame has not been received, the CPU31terminates the management process. The master ECU2may generate and transmit the NM frame, and in this case, the operation is the same as when the NM frame is received.

On the other hand, in a case where the NM frame is received, in S20, the CPU31transfers the received NM frame. That is, the CPU31transmits the received

NM frame to a slave ECU other than the transmission source slave ECU. When receiving an NM frame from the master ECU2, slave ECUs (that is, the slave ECUs4and6) that are not connected to the relays25and26bring the subject device into a wake-up state or in a sleep state based on activation information included in the received NM frame and corresponding to the subject device. For example, in a case where the activation information included in the received NM frame and corresponding to the subject device is 1, the slave ECUs4and6bring the subject device into a wake-up state.

In S30, the CPU31brings the relays25and26into an on state or an off state based on the switching information included in the NM frame received in S10, and terminates the management process. For example, in a case where the switching information included in the NM frame received in S10and corresponding to the relay25is 1, the CPU31brings the relay25into an on state.

The communication system1configured as described above includes the ECUs2to6connected so as to be capable of transmitting and receiving the CAN frame. The slave ECUs3and5receive a power supply from the battery7via relays25and26configured to switch between a conduction state in which the power supply paths10and12are conducted and a cutoff state in which the power supply paths10and12are cut off, respectively.

The master ECU2is connected to the slave ECUs3to6so as to be capable of transmitting and receiving a CAN frame, and is configured to control the operations of the relays25and26. The master ECU2is configured to bring each of the relays25and26into either a conduction state or a cutoff state based on the NM frame when receiving the NM frame. The NM frame is a CAN frame including two pieces of switching information indicating whether to bring each of the relays25and26into a conduction state and two pieces of activation information indicating whether to activate each of the slave ECUs4and6not connected to the relays25and26.

The master ECU2and the slave ECUs3to6are configured to generate and transmit an NM frame including the switching information and the activation information corresponding to the corresponding service when determining that the start condition of the service is satisfied.

In such a communication system1, the master ECU2can bring the relays25and26into either the conduction state or the cutoff state based on the two pieces of switching information included in the NM frame. Further, in the communication system1, the master ECU2can instruct the slave ECUs4and6whether to activate based on the two pieces of activation information included in the NM frame. Therefore, in a case where the ECU connected to the relay and the ECU not connected to the relay are mixed, the communication system1can individually manage the activation of the plurality of ECUs.

Upon receiving the NM frame, the master ECU2is configured to transfer the received NM frame to the slave ECUs4and6. In the communication system1, the master ECU2can instruct the slave ECUs4and6whether to activate by transferring the received NM frame. Therefore, the communication system1can simplify the processing of instructing whether to activate, and can reduce the processing load of the master ECU2.

The master ECU2includes a management table35, and each of the slave ECUs3to6includes the management table55. The management tables35and55indicate a correspondence relationship between a service, and two pieces of switching information and two pieces of activation information for each of a plurality of preset services. Accordingly, the communication system1can update the switching information and the activation information included in the NM frame transmitted by the master ECU2and the slave ECUs3to6by rewriting the management tables35and55.

In the embodiment described above, the ECUs2to6correspond to a plurality of electronic control devices. The relays25and26correspond to a power supply switching section. The battery7corresponds to a power source, the slave ECUs3and5correspond to a power supply switching device. The master ECU2corresponds to a management device.

The slave ECUs4and6correspond to a continuous power supply device. The NM frame corresponds to a management frame. S30corresponds to the process as a power supply control section. S20corresponds to the process as a transfer section.

The control sections21and41correspond to a frame generation section. The CAN communication sections22,23, and42correspond to a frame transmission section.

Second Embodiment

Hereinafter, a second embodiment of the present disclosure will be described with reference to the drawings. The second embodiment will describe parts different from the first embodiment. The same reference numerals are given to the same configurations.

As illustrated inFIG.5, the communication system1of the second embodiment differs from the first embodiment in that a smart sensor13, a smart actuator14, a wireless device15, and relays27and28are added.

The smart sensor13is a sensor including a CAN communication section45. The smart actuator14is an actuator including a CAN communication section46. The CAN communication sections45and46perform communication by transmitting and receiving a communication frame based on the CAN communication protocol with a device connected to the communication bus8.

The wireless device15is a wireless communication device for performing wireless communication with an external communication device installed outside the vehicle. The wireless device15is, for example, a DCM. DCM stands for Data Communication Module.

The relay27is disposed on a power supply path16between the battery7and the smart sensor13. The relay28is disposed on a power supply path17between the battery7and the smart actuator14.

The relays27and28are configured to switch between a conduction state in which the power supply paths16and17are conducted and a cutoff state in which the power supply paths16and17are cut off in accordance with a command from the control section21.

Hereinafter, the master ECU2, the slave ECUs3to6, the smart sensor13, and the smart actuator14are collectively referred to as nodes.

The master ECU2, the slave ECU4, and the slave ECU6are always supplied with power from the battery7without passing through a relay, and can switch between a wake-up state and a sleep state by themselves. Hereinafter, the master ECU2, the slave ECU4, and the slave ECU6are also referred to as NM-equipped nodes. An NM-equipped node is a node having a function of generating an NM frame.

The slave ECU3, the slave ECU5, the smart sensor13, and the smart actuator14are powered via the relays and cannot switch to the wake-up state or sleep state independently. In other words, they enter the wake-up state when the relay is turned on and enter the sleep state when the relay is turned off. Hereinafter, the slave ECU3, the slave ECU5, the smart sensor13, and the smart actuator14are also referred to as NM non-equipped nodes. The NM non-equipped node is a node that does not have the function to generate and interpret NM frames.

The NM non-equipped nodes include at least one of an actuator and a sensor, in addition to an ECU with control functions. The power supply paths of the NM non-equipped nodes are connected to the relays25,26,27, and28of the master ECU2, respectively.

The NM non-equipped nodes and the relays may be connected in a one-to-one manner, or multiple NM non-equipped nodes belonging to the same cluster (i.e., a group that activates simultaneously) may be connected under one relay.

The master ECU2and the NM-equipped nodes have CAN communication sections and can send and receive NM frames. The NM-equipped nodes determine whether they are in the wake-up state or sleep state based on the NM frames sent and received via the communication bus.

The master ECU2turns the relays25,26,27, and28, to which NM non-equipped nodes are connected, on or off based on the NM frames transmitted and received via the communication bus. The payload (i.e., data area) of the NM frames transmitted and received by the master ECU2and the NM-equipped nodes contains information indicating which cluster to activate, stored in one or more bits.

One or more master ECUs (i.e., ECUs with built-in relays) are installed in the vehicle. As shown inFIG.6, one or more nodes belonging to each cluster are predetermined by a system developer. It is possible to assign clusters to each node, but multiple nodes can be registered in one cluster. When the bit corresponding to each cluster is active (i.e., bit=1), that cluster will wake up. In the case of the master ECU, waking up means turning the relay to the on state.

First Activation Example

The first activation example is an operation example for performing fault diagnosis of the slave ECU3upon a request from the cloud.

First, a connection request comes from the base station (i.e., the cloud) to the vehicle's wireless device15. Next, when the wireless device15determines that the connection is valid, the wireless device15informs the master ECU2of the event received from the cloud.

Next, the master ECU2determines the service as “fault diagnosis of the slave ECU3” based on the event and generates an NM frame with the bit of the third cluster, to which only the slave ECU3belongs, set to active to activate the slave ECU3.

Next, the master ECU2transmits the generated NM frame onto the communication buses8and9. Since there are no NM-equipped nodes belonging to the third cluster on the communication buses8and9, there is no change in the devices on the communication bus.

Next, the master ECU2simultaneously executes processing based on the NM frame in the control section21as if it had received the NM frame with the bit of the third cluster set to active. Then, the control section21of the master ECU2determines the wake-up instruction for the third cluster based on the NM frame, and since the relay25is included in the third cluster, the control section21turns the relay25to the on state.

When the relay25is turned on, power is supplied to the downstream slave ECU3, which then activates. The master ECU2waits for the activation of the slave ECU3, requests the diagnostic code from the slave ECU3, and sends the response result from the slave ECU3to the base station via the wireless device15.

Second Activation Example

The second activation example is an operation example for performing fault diagnosis of the slave ECU4upon a request from the cloud.

First, a connection request comes from the base station (i.e., the cloud) to the vehicle's wireless device15. Next, when the wireless device15determines that the connection is valid, the wireless device15informs the master ECU2of the event received from the cloud.

Next, the master ECU2determines the service as “fault diagnosis of the slave ECU4” based on the event and generates an NM frame with the bit of the fourth cluster, to which only the slave ECU4belongs, set to active to activate the slave ECU4.

Next, the master ECU2transmits the generated NM frame onto the communication buses8and9. Since the slave ECU4is on the communication bus8as a node belonging to the fourth cluster, the slave ECU4wakes up.

Next, the master ECU2simultaneously executes processing based on the NM frame in the control section21as if the master ECU2had received the NM frame with the bit of the fourth cluster set to active. Then, even if the control section21of the master ECU2determines the wake-up instruction for the fourth cluster based on the NM frame, the control section21ignores it because there is no corresponding relay in the fourth cluster.

When the slave ECU4activates, the master ECU2requests the diagnostic code from the slave ECU4via the communication bus8and transmits the response result from the slave ECU4to the base station via the wireless device15.

Third Activation Example

The third activation example is an operation example where the user activates the remote air conditioning using a smartphone. First, the user instructs a vehicle air conditioner to turn on from the smartphone.

The wireless device15receives the instruction signal from the smartphone, and when the wireless device15determines that the instruction signal is valid, it informs the master ECU2of the event (i.e., instruction signal) received from the cloud.

The master ECU2determines the “air conditioning service” based on the event and generates an NM frame with the second cluster set to active as the air conditioning cluster. The master ECU2periodically transmits the generated NM frame onto the communication buses8and9until an air conditioner stop instruction is issued. When it is desired to continue the active state, it is necessary to continue transmitting the NM frame periodically. Simultaneously, the control section21of the master ECU2executes processing based on the NM frame.

When the NM frame with the second cluster set to active appears on the communication bus8, the slave ECU4(i.e., air conditioner ECU) belonging to the second cluster receives the NM frame and wakes up according to the received NM frame.

When the control section21of the master ECU2detects that the second cluster is active, it turns the relays27and28belonging to the second cluster to the on state. When the relays27and28are turned on, power is supplied to the smart sensor13(i.e., a temperature sensor) and the smart actuator14(i.e., a compressor).

As a result, power supply to the air conditioner ECU, the smart sensor13, and the smart actuator14begins, making it possible to turn on the vehicle air conditioner. When the user instructs the vehicle air conditioner to turn off from the smartphone, the master ECU2stops the periodic transmission of the NM frame.

When the NM frame is interrupted, the slave ECU4transitions to the sleep state, and the master ECU2turns off the relays27and28. As a result, the vehicle air conditioner stops.

Fourth Activation Example

The fourth activation example is an operation example where the vehicle air conditioner is activated from the slave ECU4.

Since the slave ECU4is always supplied with power even when the vehicle is stopped, the slave ECU4can wake up by detecting the input of a signal indicating that the activation switch connected to the slave ECU4has been turned on, even while in sleep mode.

When the slave ECU4wakes up and confirms the input to be activated regarding the vehicle air conditioner, the slave ECU4generates an NM frame with the bit corresponding to the second cluster set to on. The slave ECU4transmits the generated NM frame via the CAN communication section42. When the master ECU2receives this NM frame, the master ECU2turns the relays27and28belonging to the second cluster to the on state.

When the activation switch of the vehicle air conditioner is turned off, the slave ECU4stops transmitting the NM frame and transitions to the sleep state after a while. When the NM frame is interrupted, the master ECU2turns off the relays27and28after a while and ends the control.

If the master ECU2determines that it is necessary to continue control even after the NM frame transmission is stopped, the master ECU2transmits an NM frame with the bit corresponding to the second cluster set to on. As a result, the slave ECU4and the relays27and28can maintain the activation state until the transmission of the NM frame generated by the master ECU2is stopped.

The NM-equipped nodes are supplied with power without relays and can execute shutdown processes to transition to a low power state within the node. However, the NM non-equipped nodes cannot perform shutdown processes if the power supply is suddenly cut off by turning off the relay. Shutdown processes may include, for example, saving logs in operation, saving diagnostic data, saving learning results, and setting input/output devices to their initial positions for the next startup.

The communication system1of the second embodiment can implement the following first, second, third, and fourth measures to secure time for the shutdown process.

The master ECU2, which controls the relays25,26,27, and28, notifies the subordinate nodes (i.e., the slave ECUs3,5, the smart sensor13, and the smart actuator14) of a relay-off pre-notification message via the CAN communication section22before executing the relay-off. Additionally, the master ECU2stops transmitting non-emergency CAN communications. The pre-notification message only needs to have a predetermined CAN ID and data pattern.

The master ECU2manages the time required for the shutdown process of the subordinate nodes (i.e., the slave ECUs3,5, the smart sensor13, and the smart actuator14). After sending the aforementioned pre-notification message, the master ECU2measures the elapsed time and turns off the relays25,26,27, and28if the required shutdown time is exceeded. The NM non-equipped nodes stop communication, execute the shutdown process, and wait for the power supply to be cut off upon receiving the relay-off pre-notification message.

The master ECU2notifies the subordinate nodes (i.e., the slave ECUs3,5, the smart sensor13, and the smart actuator14) of a relay-off pre-notification message via the CAN communication section22before executing the relay-off. Additionally, the master ECU2stops transmitting non-emergency CAN communications. The pre-notification message only needs to have a predetermined CAN ID and data pattern.

The master ECU2manages the time required for the shutdown process of each subordinate node (i.e., the slave ECUs3,5, the smart sensor13, and the smart actuator14) individually. After sending the aforementioned pre-notification message, the master ECU2measures the elapsed time and sequentially turns off the relays corresponding to the nodes if the required shutdown time is exceeded. The NM non-equipped nodes stop communication, execute the shutdown process, and wait for the power supply to be cut off upon receiving the relay-off pre-notification message.

The master ECU2and the NM-equipped nodes synchronize sleep timing by mutually transmitting and receiving NM frames.

When the sleep condition is met upon the termination of the provided service, the master ECU2stops communication including the NM frames. Then, the master ECU2turns off the relays after the sum of the time for the NM non-equipped nodes to determine the absence of the NM frames (e.g., 3 seconds) and the time required for the shutdown process of the NM non-equipped nodes (e.g., 2 seconds) has elapsed (e.g., 5 seconds). The NM non-equipped nodes monitor the NM frames on the communication bus8and stop transmitting to the communication bus8, execute the shutdown process, and wait for the power supply to be cut off if the absence of the NM frames is detected for a certain period (e.g., 3 seconds).

The NM non-equipped nodes can transmit a predetermined command to the master ECU2to request an extension of the time before the relay is turned off if they are unlikely to complete the shutdown process within the predetermined required time.

The master ECU2and the NM-equipped nodes synchronize sleep timing by mutually transmitting and receiving the NM frames.

When the sleep condition of a predetermined cluster is met upon the termination of the provided service, the master ECU2sets the bits corresponding to the cluster in the NM frame to 0. After all bits become 0 and a certain period (e.g., 3 seconds) has elapsed, the master ECU2stops communication including the NM frames. Then, the master ECU2turns off the relays after the time required for the shutdown process of the NM non-equipped nodes (e.g., 2 seconds) has elapsed. Here, the NM non-equipped nodes have the function to receive and interpret the NM frames. The NM non-equipped nodes always monitor the NM frames transmitted by the master ECU2and start the shutdown process when all bits of the cluster including the upstream relay supplying power to the node are 0. This allows the NM non-equipped nodes to complete the shutdown process before the relay supplying power to the node is turned off. The NM-equipped nodes sleep according to the NM frames exchanged with the master ECU2.

The NM non-equipped nodes can transmit a predetermined command to the master ECU2to request an extension of the time before the relay is turned off if they are unlikely to complete the shutdown process within the predetermined required time. In this case, the master ECU2waits to turn off the relay while receiving the extension request from the NM non-equipped nodes.

Third Embodiment

The third embodiment of the present disclosure will be described below with reference to the drawings. The third embodiment will describe parts different from the first embodiment.

As illustrated inFIG.7, the communication system100of the third embodiment includes a central ECU101, upstream power distribution sections102and103, zone ECUs104,105,106, and107, slave ECUs108,109,110,111,112,113,114,115, and116, a battery117, and a slave ECU118. Hereinafter, the central ECU101, the zone ECUs104to107, and the slave ECUs108to116and118are collectively referred to as nodes.

The battery117supplies power to each section of the vehicle with a direct-current battery voltage (for example, 12 V). The central ECU101, upstream power distribution sections102and103, the zone ECUs104to107, and the slave ECUs108to116and118operate by receiving a power supply from the battery117.

The upstream power distribution section102receives a power supply from the battery117via a power supply path121between the battery7and the upstream power distribution section102. The upstream power distribution section103receives a power supply from the battery117via a power supply path122between the battery7and the upstream power distribution section103.

The zone ECUs104and105receive a power supply from the battery117via power supply paths123and124between the upstream power distribution section102and the zone ECUs104and105, respectively.

The zone ECUs106and107receive a power supply from the battery117via power supply paths125and126between the upstream power distribution section103and the zone ECUs106and107, respectively.

The slave ECUs108and109receive a power supply from the battery117via power supply paths127and128between the zone ECU104and the slave ECUs108and109, respectively.

The slave ECUs110and111receive a power supply from the battery117via power supply paths129and130between the zone ECU105and the slave ECUs110and111, respectively.

The slave ECUs112,113, and114receive a power supply from the battery117via power supply paths131,132, and133between the zone ECU106and the slave ECUs112,113, and114, respectively.

The slave ECUs115and116receive a power supply from the battery117via power supply paths134and135between the zone ECU107and the slave ECUs115and116, respectively.

The slave ECU118receives a power supply from the battery117via a power supply path136. The central ECU101and the upstream power distribution section102are data-communicably connected to each other via a communication line141.

The central ECU101and the upstream power distribution section103are data-communicably connected to each other via a communication line142. The central ECU101and the zone ECUs104,105,106, and107are data-communicably connected to each other via communication lines143,144,145, and146, respectively.

The zone ECU104and the slave ECUs108,109, and118are data-communicably connected to each other via a communication bus147. The zone ECU105and the slave ECUs110and111are data-communicably connected to each other via a communication bus148.

The zone ECU106and the slave ECUs112,113, and114are data-communicably connected to each other via a communication bus149. The zone

ECU107and the slave ECUs115and116are data-communicably connected to each other via a communication bus150.

As illustrated inFIG.8, the central ECU101includes a control section151, communication sections152,153,154,155,156, and157, and a storage section158. The control section151is an electronic control device mainly including a microcomputer including a CPU161, a ROM162, a RAM163, and the like. Various functions of the microcomputer are implemented by the CPU161executing a program stored in a non-transitory tangible storage medium. In this example, the ROM162corresponds to a non-transitory tangible storage medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU161may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section151may be one or more.

The communication section152performs communication with the upstream power distribution section102connected to the communication line141by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol. Ethernet is a registered trademark.

The communication section153performs communication with the upstream power distribution section103connected to the communication line142by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol. The communication section154performs communication with the zone ECU104connected to the communication line143by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol.

The communication section155performs communication with the zone ECU105connected to the communication line144by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol. The communication section156performs communication with the zone ECU106connected to the communication line145by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol.

The communication section157performs communication with the zone ECU107connected to the communication line145by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol. The storage section158is a storage device for storing various pieces of data. The storage section158stores a management table165and a diagnostic mask table167to be described later.

The upstream power distribution section102includes a control circuit171, a communication section172, and electronic fuses173and174. The control circuit171controls switching of the electronic fuses173and174between an on state and an off state based on instructions obtained via the communication section172from the central ECU101.

The communication section172performs communication with the central ECU101connected to the communication line141by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol.

The electronic fuse173is disposed between the power supply path121and the power supply path123. The electronic fuse174is disposed between the power supply path121and the power supply path124. The upstream power distribution section103includes a control circuit181, a communication section182, and electronic fuses183and184.

The control circuit181controls switching of the electronic fuses183and184between an on state and an off state based on instructions obtained via the communication section182from the central ECU101.

The communication section182performs communication with the central ECU101connected to the communication line142by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol.

The electronic fuse183is disposed between the power supply path122and the power supply path125. The electronic fuse184is disposed between the power supply path122and the power supply path126. As illustrated inFIG.9, the zone ECU104includes a control section191, a communication section192, a CAN communication section193, a storage section194, and electronic fuses195and196.

The control section191is an electronic control device mainly including a microcomputer including a CPU201, a ROM202, a RAM203, and the like. Various functions of the microcomputer are implemented by the CPU201executing a program stored in a non-transitory tangible storage medium. In this example, the ROM202corresponds to a non-transitory tangible storage medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU201may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section191may be one or more.

The communication section192performs communication with the central ECU101connected to the communication line143by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol.

The CAN communication section193performs communication with the slave ECUs108and109connected to the communication bus147by transmitting and receiving a communication frame based on the CAN communication protocol.

The storage section194is a storage device for storing various pieces of data. The storage section194stores a management table205and a diagnostic mask table207to be described later. The electronic fuse195is disposed between the power supply path123and the power supply path127. The electronic fuse196is disposed between the power supply path123and the power supply path128.

The zone ECU105includes a control section211, a communication section212, a CAN communication section213, a storage section214, and electronic fuses215and216. The control section211is an electronic control device mainly including a microcomputer including a CPU221, a ROM222, a RAM223, and the like. Various functions of the microcomputer are implemented by the CPU221executing a program stored in a non-transitory tangible storage medium. In this example, the ROM222corresponds to a non-transitory tangible storage medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU221may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section211may be one or more.

The communication section212performs communication with the central ECU101connected to the communication line144by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol.

The CAN communication section213performs communication with the slave ECUs110and111connected to the communication bus148by transmitting and receiving a communication frame based on the CAN communication protocol.

The storage section214is a storage device for storing various pieces of data. The storage section214stores a management table225and a diagnostic mask table227to be described later. The electronic fuse215is disposed between the power supply path124and the power supply path129. The electronic fuse216is disposed between the power supply path124and the power supply path130.

As illustrated inFIG.10, the zone ECU106includes a control section231, a communication section232, a CAN communication section233, a storage section234, and electronic fuses235,236, and237. The control section231is an electronic control device mainly including a microcomputer including a CPU241, a ROM242, a RAM243, and the like. Various functions of the microcomputer are implemented by the CPU241executing a program stored in a non-transitory tangible storage medium. In this example, the ROM242corresponds to a non-transitory tangible storage medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU241may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section231may be one or more.

The communication section232performs communication with the central ECU101connected to the communication line145by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol.

The CAN communication section233performs communication with the slave ECUs112,113, and114connected to the communication bus149by transmitting and receiving a communication frame based on the CAN communication protocol.

The storage section234is a storage device for storing various pieces of data. The storage section194stores a management table245and a diagnostic mask table247to be described later. The electronic fuse235is disposed between the power supply path125and the power supply path131. The electronic fuse236is disposed between the power supply path125and the power supply path132. The electronic fuse237is disposed between the power supply path125and the power supply path133.

The zone ECU107includes a control section251, a communication section252, a CAN communication section253, a storage section254, and electronic fuses255and256. The control section251is an electronic control device mainly including a microcomputer including a CPU261, a ROM262, a RAM263, and the like. Various functions of the microcomputer are implemented by the CPU261executing a program stored in a non-transitory tangible storage medium. In this example, the ROM262corresponds to a non-transitory tangible storage medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU261may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section251may be one or more.

The communication section252performs communication with the central ECU101connected to the communication line146by transmitting and receiving a communication frame based on, for example, the Ethernet communication protocol.

The CAN communication section253performs communication with the slave ECUs115and116connected to the communication bus150by transmitting and receiving communication frames based on the CAN communication protocol.

The storage section254is a storage device for storing various pieces of data. The storage section254stores a management table265and a diagnostic mask table267to be described later. The electronic fuse255is disposed between the power supply path126and the power supply path134. The electronic fuse256is disposed between the power supply path126and the power supply path135.

As illustrated inFIG.11, the slave ECUs108,109, and118include a control section271, a CAN communication section272, and a storage section273. The control section271is an electronic control device mainly including a microcomputer including a CPU281, a ROM282, a RAM283, and the like. Various functions of the microcomputer are implemented by the CPU281executing a program stored in a non-transitory tangible storage medium. In this example, the ROM282corresponds to a non-transitory tangible storage medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU281may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section271may be one or more.

The CAN communication section272performs communication with the zone ECU104connected to the communication bus147by transmitting and receiving communication frames based on the CAN communication protocol. The storage section273is a storage device for storing various pieces of data. The storage section273stores a management table285and a diagnostic mask table287to be described later.

The slave ECUs110and111include a control section291, a CAN communication section292, and a storage section293. The control section291is an electronic control device mainly including a microcomputer including a CPU301, a ROM302, a RAM303, and the like. Various functions of the microcomputer are implemented by the CPU301executing a program stored in a non-transitory tangible storage medium. In this example, the ROM302corresponds to a non-transitory tangible storage medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU301may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section291may be one or more.

The CAN communication section292performs communication with the zone ECU105connected to the communication bus148by transmitting and receiving communication frames based on the CAN communication protocol. The storage section293is a storage device for storing various pieces of data. The storage section293stores a management table305and a diagnostic mask table307to be described later.

The slave ECUs112,113, and114include a control section311, a CAN communication section312, and a storage section313. The control section311is an electronic control device mainly including a microcomputer including a CPU321, a ROM322, a RAM323, and the like. Various functions of the microcomputer are implemented by the CPU321executing a program stored in a non-transitory tangible storage medium. In this example, the ROM322corresponds to a non-transitory tangible storage medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU321may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section311may be one or more.

The CAN communication section312performs communication with the zone ECU106connected to the communication bus149by transmitting and receiving communication frames based on the CAN communication protocol. The storage section313is a storage device for storing various pieces of data. The storage section313stores a management table325and a diagnostic mask table327to be described later.

The slave ECUs115and116include a control section331, a CAN communication section332, and a storage section333. The control section331is an electronic control device mainly including a microcomputer including a CPU341, a ROM342, a RAM343, and the like. Various functions of the microcomputer are implemented by the CPU341executing a program stored in a non-transitory tangible recording medium. In this example, the ROM342corresponds to a non-transitory tangible recording medium storing a program. Further, by executing this program, a method corresponding to the program is executed. Some or all of the functions executed by the CPU341may be configured as hardware by one or a plurality of ICs or the like. Furthermore, the number of microcomputers constituting the control section331may be one or more.

The CAN communication section332performs communication with the zone ECU107connected to the communication bus150by transmitting and receiving communication frames based on the CAN communication protocol. The storage section333is a storage device for storing various pieces of data. The storage section333stores a management table345and a diagnostic mask table347to be described later.

The management tables165,205,225,245,265,285,305,325, and345set a correspondence relationship between a service, and switching information and activation information for each of a plurality of services provided to an occupant of a vehicle using the central ECU101, the zone ECUs104to107, and the slave ECUs108to116and118.

Therefore, in the management tables165,205,225,245,265,285,305,325, and345, switching information is set for the electronic fuses173,174,183,184,195,196,215,216,235,236,237,255, and256, and activation information is set for the central ECU101and the slave ECU118.

The management tables165,205,225,245,265,285,305,325, and345may not store switching information and activation information for services that the subject device cannot detect the establishment of the service start condition.

The diagnostic mask tables167,207,227,247,267,287,307,327, and347set a correspondence relationship between a slave ECU (hereinafter, cutoff ECU) whose power supply via an electronic fuse is cut off and a CAN ID (hereinafter, non-reception frame ID) of a CAN frame which is not received, and a slave ECU (hereinafter, sleep ECU) which is brought into a sleep state and the CAN ID, for each service.

Therefore, when detecting that the start condition of the service is satisfied based on the detected event, the central ECU101, zone ECUs104to107, and slave ECUs108to116and118extract the switching information and activation information corresponding to the corresponding service from the management tables165,205,225,245,265,285,305,325, and345, generate and transmit the NM frame including the extracted switching information and activation information. Further, the central ECU101, zone ECUs104to107, and slave ECUs108to116and118extract a combination of the cutoff ECU or the sleep ECU corresponding to the corresponding service and the non-reception frame ID from the diagnostic mask tables167,207,227,247,267,287,307,327, and347to transmit the extracted combination as diagnostic mask information.

Next, a procedure of a central management process executed by the control section151of the central ECU101will be described. The central management process is a process repeatedly executed during activation of the central ECU101.

When the central management process is executed, in S110, the CPU161of the control section151determines whether an NM frame has been received as illustrated inFIG.12. Here, in a case where the NM frame has not been received, the CPU161proceeds to S140.

On the other hand, in a case where the NM frame is received, in S120, the CPU161transfers the received NM frame to the zone ECUs104to107. The zone ECUs104to107that have received the NM frame from the central ECU101transfer the NM frame to the subordinate slave ECUs. Further, the zone ECUs104to107that have received the NM frame from the central ECU101turn on or off the built-in electronic fuses based on the switching information included in the received NM frame.

In S130, the CPU161sends a power supply switching control instruction to the upstream power distribution sections102and103to turn on or off the electronic fuses173,174,183, and184of the upstream power distribution sections102and103based on the switching information included in the NM frame received in S110, and then proceeds to S140.

In S140, the CPU161determines whether a service start condition preset for the central ECU101has been satisfied. Here, in a case where the service start condition is not satisfied, the CPU161terminates the central management process.

On the other hand, in a case where the service start condition is satisfied, in S150, the CPU161extracts the switching information and activation information corresponding to the service satisfied in S140from the management table165, generates the NM frame including the extracted switching information and activation information, and transmits it to the zone ECUs104to107.

In S160, the CPU161transmits a power supply switching control instruction to the upstream power distribution sections102and103to turn on or off the electronic fuses173,174,183, and184of the upstream power distribution sections102and103based on the switching information corresponding to the service satisfied in S140by referring to the management table165, and then terminates the central management process.

The communication system100configured as described above includes the ECUs101and104to116and118connected so as to be capable of transmitting and receiving communication frames. The slave ECUs108and109receive a power supply from the battery117via the electronic fuses195and196configured to switch between a conduction state in which the power supply paths127and128are conducted and a cutoff state in which the power supply paths127and128are cut off, respectively.

The central ECU101is connected to the zone ECU104and the slave ECUs108and109so as to be capable of transmitting and receiving communication frames, and is configured to control the operations of the electronic fuses195and196.

The ECUs101and104to116and118are configured to determine the provision of a preset service based on the detected event and generate an NM frame according to the service. The NM frame is a communication frame including switching information indicating whether to bring each of the electronic fuses195,196,215,216,235,236,237,255, and256into a conduction state and activation information indicating whether to activate the slave ECU118not connected to the electronic fuses.

The ECUs101and104to116and118are configured to transmit the generated management frame. The central ECU101is configured to bring each of the electronic fuses195and196into either a conduction state or a cutoff state based on the NM frame.

In such a communication system100, the central ECU101can bring the electronic fuses195and196into either the conduction state or the cutoff state based on the two pieces of switching information included in the NM frame. Further, in the communication system100, the central ECU101can instruct the slave ECU118whether to activate based on the one piece of activation information included in the NM frame. Therefore, in a case where the ECU connected to the electronic fuse and the ECU not connected to the electronic fuse are mixed, the communication system100can individually manage the activation of the plurality of ECUs.

In the embodiment described above, the ECUs101and104to116and118correspond to a plurality of electronic control devices, the electronic fuses195and196correspond to a power supply switching section, the battery117corresponds to a power source, the slave ECUs108and109correspond to a power supply switching device, and the central ECU101corresponds to a management device.

The slave ECU118corresponds to a continuous power supply device, the NM frame corresponds to a management frame, S130corresponds to the process as a power supply control section. Further, the control sections151,191,211,231,251,271,291,311, and331correspond to a frame generation section, and the communication sections154to157,192,212,232,252, and the CAN communication sections193,213,233,253,272,292,312, and332correspond to a frame transmission section.

Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment and can be implemented in various modifications. The control sections21and41and their methods described in the present disclosure may be implemented by a dedicated computer provided by configuring a processor and memory programmed to execute one or more functions embodied by a computer program. Alternatively, the control sections21and41and their methods described in the present disclosure may be implemented by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control sections21and41and their methods described in the present disclosure may be implemented by one or more dedicated computers configured by a combination of a processor and memory programmed to execute one or more functions and one or more hardware logic circuits. The computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by a computer. The method for realizing the functions of each section included in the control sections21and41does not necessarily need to include software, and all the functions may be realized using one or more hardware.

The multiple functions possessed by one component in the above embodiment may be realized by multiple components, or one function possessed by one component may be realized by multiple components. Further, multiple functions possessed by multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Further, part of the configuration of the above embodiment may be omitted. Further, at least part of the configuration of the above embodiment may be added to or replaced with the configuration of another embodiment.

In addition to the ECUs2to6,101, and104to116and118described above, the present disclosure can also be realized in various forms such as a system including the ECUs2to6,101, and104to116and118as components, a program for causing a computer to function as the ECUs2to6,101, and104to116and118, a non-transitory tangible recording medium such as a semiconductor memory recording the program, and a communication management method.