Electronic control apparatus and communication system

Abstract

To reduce power consumption in a communication system.SOLUTION: Slave ECUs 3 to 5 receive electricity supplied from a battery 7 via relays 15 to 17, respectively. When a preset shut-off condition is established, each of the slave ECUs 3 to 5 transmits a termination notification to a master ECU 2. The master ECU 2 is configured to be connected so as to communicate data to / from the slave ECUs 3 to 5 and transmit / receive a CAN frame, and controls operations of the relays 15 to 17. After the shut-off condition is established, if each of the slave ECUs 3 to 5 does not receive any CAN frame transmitted thereto before a reception determination time passes, the slave ECUs 3 to 5 enter sleep state.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an electronic control device and a communication system.

Background Art

[0002] Patent Document 1 discloses an in-vehicle network system that includes a power relay for individually switching on / off the power supply of an electronic control device for each of a plurality of electronic control devices, determines control content for switching on / off the power supply of a specific electronic control device corresponding to a specific scene specified based on the vehicle situation, and switches on / off the power supply supplied to the specific electronic control device using the power relay based on the determined control content.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As a result of the inventors' detailed examination, it has been found that there is a problem in that power may be wasted in a communication system including a plurality of control devices and configured to switch on / off the power supply of the control devices.

[0005] An object of the present disclosure is to reduce power consumption in a communication system.

Means for Solving the Problems

[0006] One aspect of the present disclosure is an electronic control device (3, 4, 5, 104 to 116) configured to receive power supply from a power source (7, 51, 52, 117) via a power supply switching unit (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conducting state for conducting a power supply path and a blocking state for blocking the power supply path.

[0007] The electronic control device of the present disclosure includes an end notification unit (S10, S20, S310, S320, S325) and a sleep transition unit (S30 to S60, S330 to S360). The end notification unit is configured to transmit an end notification to a power supply control device (2, 101 to 107) when a preset blocking condition indicating that the power supply switching unit connected to the electronic control device may be set to the blocking state is satisfied. The power supply control device is configured to be connected to the electronic control device so as to be capable of data communication, configured to be capable of transmitting and receiving communication frames, and configured to control the operation of the power supply switching unit.

[0008] The sleep transition unit is configured to transition the electronic control device to a sleep state when, after the blocking condition is satisfied, communication frames are not received from all of one or a plurality of communication devices (2 to 5, 101 to 116, 118) that are connected to the electronic control device so as to be capable of data communication before a preset reception determination time elapses.

[0009] Even when a failure occurs in which the power supply control device that has received the end notification from the electronic control device cannot switch the power supply switching unit to the off state while attempting to switch it to the off state, the electronic control device of the present disclosure can be shifted to the sleep state. Therefore, even though the electronic control device of the present disclosure may be in a state where it is acceptable to stop the operation of the electronic control device by turning off the power supply switching unit, the situation where the power supply switching unit is in the conductive state and the electronic control device is in the wake-up state continues, and the electronic control device consumes power uselessly can be suppressed, and power consumption in the communication system can be reduced.

[0010] Another aspect of the present disclosure is an electronic control device (3, 4, 5, 104 to 116) configured to receive power supply from a power source (7, 117) via at least one of a plurality of power supply switching units (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conductive state for conducting a power supply path and an off state for interrupting the power supply path.

[0011] The electronic control device of the present disclosure includes a shift unit during interruption (S220 to S240, S520 to S540). When the shift unit during interruption receives power supply switching state information from the power supply control device (2, 101 to 107), based on the received power supply switching state information, when all of the plurality of power supply switching units are in the off state, or when all of the power supply switching units other than the power supply switching unit connected to the electronic control device among the plurality of power supply switching units are in the off state, the electronic control device is configured to shift to the stop state or the sleep state. The power supply control device is configured to be connected to the electronic control device so as to enable data communication and to control the operation of the plurality of power supply switching units. The power supply switching state information indicates whether each of the plurality of power supply switching units is in the conductive state or the off state.

[0012] The electronic control device of the present disclosure configured as described above can suppress the occurrence of a situation where, even though all of the plurality of power supply switching units are in an off state or all of the power supply switching units other than those connected to the electronic control device are in an off state, which is an abnormal state, the electronic control device continues to operate and consumes power uselessly, and can reduce power consumption in the communication system.

[0013] Another aspect of the present disclosure is a communication system (1, 100) including a first control device (3, 4, 5, 104 to 116) and a second control device (2, 101 to 107). The first control device receives power supply from a power source (7, 51, 52, 117) via a power supply switching unit (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conducting state for conducting a power supply path and a blocking state for blocking the power supply path. The second control device is connected to be capable of data communication with the first control device, is configured to be capable of transmitting and receiving communication frames, and is configured to control the operation of the power supply switching unit.

[0014] The first control device includes an end notification unit (S10, S20, S310, S320, S325) and a sleep transition unit (S30 to S60, S330 to S360). The end notification unit is configured to transmit an end notification to the second control device when a preset blocking condition indicating that the power supply switching unit connected to the first control device may be set to the blocking state is satisfied.

[0015] The sleep transition unit is configured to transition the first control device to a sleep state when, after the blocking condition is satisfied, all of one or a plurality of communication devices (2 to 5, 101 to 116, 118) connected to be capable of data communication with the first control device do not receive a communication frame until a preset reception determination time elapses.

[0016] Even when a failure occurs in which the second control device that has received an end notification from the first control device cannot switch the power supply switching unit to the cutoff state even though it attempts to switch the power supply switching unit to the cutoff state, the first control device can be shifted to the sleep state. Therefore, even though the communication system of the present disclosure may be in a state where the power supply switching unit can be put in the cutoff state to stop the operation of the first control device, the state where the power supply switching unit is in the conductive state and the first control device is in the wake-up state continues, and it is possible to suppress the occurrence of a situation where the first control device consumes power uselessly, and it is possible to reduce power consumption in the communication system.

[0017] Still another aspect of the present disclosure is a communication system (1, 100) including a plurality of power supply switching units (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256), a first control device (3, 4, 5, 104 to 116), and a second control device (2, 101 to 107). The plurality of power supply switching units are configured to switch between a conductive state in which a power supply path is made conductive and a cutoff state in which the power supply path is cut off. The first control device receives power supply from a power source (7) via at least one of the plurality of power supply switching units. The second control device is connected to be capable of data communication with the first control device and is configured to control the operation of the plurality of power supply switching units.

[0018] The second control device includes a state information transmission unit (S120, S420). The state information transmission unit is configured to transmit power supply switching state information indicating whether each of the plurality of power supply switching units is in the conductive state or the cutoff state to the first control device.

[0019] The first control device includes a cut-off transition unit (S220~S240, S520~S540). When all of the plurality of power supply switching units are in the cut-off state based on the power supply switching state information received from the second control device, or when all of the power supply switching units other than the power supply switching unit connected to the first control device among the plurality of power supply switching units are in the cut-off state, the cut-off transition unit is configured to shift the first control device to a stop state or a sleep state.

[0020] In the communication system of the present disclosure configured as described above, even when all of the plurality of power supply switching units are in the cut-off state or all of the power supply switching units other than the power supply switching unit connected to the first control device are in the cut-off state, which is an abnormal state, it is possible to suppress the occurrence of a situation where the first control device continues to operate and the first control device consumes power uselessly, and it is possible to reduce power consumption in the communication system.

Brief Description of the Drawings

[0021]

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Embodiments for Carrying Out the Invention

[0022] [First Embodiment] The first embodiment of the present disclosure will be described below with reference to the drawings. The communication system 1 of this embodiment is mounted on a vehicle and includes, as shown in FIG. 1, a master ECU 2, slave ECUs 3, 4, 5, 6, and a battery 7. ECU is an abbreviation for Electronic Control Unit. Hereinafter, the master ECU 2 and the slave ECUs 3 to 6 are collectively referred to as nodes.

[0023] The master ECU 2 and the slave ECUs 3, 4, and 5 are connected to each other via a communication bus 8 so as to be capable of data communication with each other. The master ECU 2 and the slave ECU 6 are connected to each other via a communication bus 9 so as to be capable of data communication with each other.

[0024] The battery 7 supplies power to each part of the vehicle with a DC battery voltage (for example, 12V). The master ECU 2 and the slave ECUs 3 to 6 operate by receiving power supply from the battery 7.

[0025] The master ECU 2 includes a control unit 11, CAN communication units 12 and 13, a storage unit 14, and relays 15, 16, and 17. CAN is an abbreviation for Controller Area Network. Note that the communication protocol of the communication system 1 is not limited to CAN.

[0026] The control unit 11 is an electronic control device mainly configured around a microcomputer including a CPU 21, a ROM 22, a RAM 23, etc. Various functions of the microcomputer are realized by the CPU 21 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 22 corresponds to the non-transitory tangible recording medium storing the program. Further, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 21 may be configured hardware-wise by one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control unit 11 may be one or a plurality.

[0027] The CAN communication unit 12 communicates with the slave ECUs 3, 4, and 5 connected to the communication bus 8 by transmitting and receiving communication frames based on the CAN communication protocol. The CAN communication unit 13 communicates with the slave ECU 6 connected to the communication bus 9 by transmitting and receiving communication frames based on the CAN communication protocol. Hereinafter, the communication frame of CAN is referred to as a CAN frame.

[0028] The storage unit 14 is a storage device for storing various data. The storage unit 14 stores a management table 25, which will be described later. Relay 15 is arranged on the power supply path between the battery 7 and the slave ECU 3. Relay 16 is arranged on the power supply path between the battery 7 and the slave ECU 4. Relay 17 is arranged on the power supply path between the battery 7 and the slave ECU 5.

[0029] Relays 15, 16, and 17 are configured to switch between a conducting state in which the power supply path is conducted and a blocking state in which the power supply path is blocked according to a command from the control unit 11. Hereinafter, the conducting state is also referred to as the on state, and the blocking state is also referred to as the off state.

[0030] The slave ECUs 3 to 6 include a control unit 31, a CAN communication unit 32, and a storage unit 33. The control unit 31 is an electronic control device mainly configured around a microcomputer including a CPU 41, a ROM 42, a RAM 43, etc. Various functions of the microcomputer are realized by the CPU 41 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 42 corresponds to the non-transitory tangible recording medium storing the program. Further, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 41 may be configured hardware-wise by one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control unit 31 may be one or plural.

[0031] The CAN communication units 32 of the slave ECUs 3 to 5 communicate with communication devices (i.e., the master ECU 2 and the slave ECUs 3 to 5) connected to the communication bus 8 based on the CAN communication protocol.

[0032] The CAN communication unit 32 of the slave ECU 6 communicates with a communication device (i.e., the master ECU 2) connected to the communication bus 9 based on the CAN communication protocol. The storage unit 33 is a storage device for storing various data.

[0033] The CAN frame is composed of a start of frame, an arbitration field, a control field, a data field, a CRC field, an ACK field, and an end of frame. Note that the arbitration field is composed of an 11-bit or 29-bit identifier (i.e., ID) and a 1-bit RTR bit.

[0034] The 11-bit identifier used in CAN communication is called a CANID. The CANID is preset based on the content of the data included in the CAN frame, the source of the CAN frame, the destination of the CAN frame, etc.

[0035] The data field is a payload composed of the first data, second data, third data, fourth data, fifth data, sixth data, seventh data, and eighth data, each of which is 8 bits (i.e., 1 byte).

[0036] The master ECU2 and slave ECUs3 to 6 are configured to switch between a wake-up state (i.e., an activated state) and a sleep state (i.e., a dormant state). The wake-up state is a normal operating state in which the functions assigned to the ECU can be used without restriction. The sleep state is a low-power operating state in which the available functions are restricted. In the sleep state, many functions are stopped for power saving, and only some functions (e.g., the function of receiving CAN frames) are available.

[0037] The communication system 1 forms a partial network, which is a power supply control method based on the communication control of the CAN protocol standard defined in ISO11898-6. For this reason, the communication system 1 realizes low power consumption by individually shifting one or more nodes belonging to the communication group to the wake-up state or the sleep state for each communication group described later.

[0038] In communication system 1, when waking up a node in the sleep state, an NM frame, which is a CAN frame containing startup information specifying a startup group, is used. NM is the abbreviation of Network Management.

[0039] The startup information is set as shown in FIG. 6, for example. DLC is the abbreviation of Data Length Code and is an area representing the size of the data field in the CAN frame in byte units. That is, the startup information is stored in the data field of the CAN frame. Here, for simplicity of explanation, the case where DLC is 1 byte (i.e., 8 bits) is shown. Each bit of the 8-bit data representing the startup information is associated with a startup group.

[0040] In the startup information set in the NM frame, the bit corresponding to the startup group to be started is set to 1. Each node stores affiliation information indicating the startup group to which the self-node belongs. The affiliation information has the same data length as the startup information, and the assignment of each bit is also the same as that of the startup information. And in the affiliation information, the bit corresponding to the startup group to which the self-node belongs is set to 1.

[0041] Each node determines whether the communication group to which the self-node belongs is a startup target by comparing the startup information extracted from the NM frame with the affiliation information stored in the self-node.

[0042] For example, the affiliation information shown in FIG. 6 indicates that it belongs to the first communication group, the third communication group, and the fifth communication group. The startup information shown in FIG. 6 indicates that the second communication group, the third communication group, the fourth communication group, and the fifth communication group are to be started. Since the third communication group and the fifth communication group are included in both the affiliation information and the startup information shown in FIG. 6, the self-node determines that the self-node is a startup target as the third communication group and the fifth communication group.

[0043] The management table 25 shown in FIG. 1 sets the correspondence relationship between a communication group and one or more nodes (i.e., one or more nodes to be activated) belonging to the corresponding communication group for each of a plurality of communication groups.

[0044] For example, the management table 25 sets that the master ECU 2 and the slave ECUs 3 and 4 belong to the first communication group. For example, the management table 25 sets that the slave ECUs 3, 4, and 5 belong to the second communication group.

[0045] Also, the master ECU 2 and the slave ECUs 3 to 6 are configured to generate and transmit an NM frame including information indicating a communication group involved in a corresponding event as the above activation information when detecting that the start condition of the event is satisfied for each of a plurality of events.

[0046] The procedure of the state transition process executed by the control units 31 of the slave ECUs 3 to 5 will be described. The state transition process is a process repeatedly executed during the operation of the slave ECUs 3 to 5. When the state transition process is executed, the CPU 41 of the control unit 31 determines, as shown in FIG. 2, whether a preset cutoff condition is satisfied at S10. The cutoff condition of the present embodiment includes that the slave ECUs 3 to 5 are in a state where they may transition from the wake-up state to the sleep state. That is, for each of the slave ECUs 3 to 5, the cutoff condition is satisfied when there is no need to control the control target controlled by the slave ECUs 3 to 5.

[0047] For example, when the control target of the slave ECU 3 is the in-vehicle air conditioner and the vehicle occupant performs an operation to turn off the in-vehicle air conditioner, the slave ECU 3 no longer needs to control the in-vehicle air conditioner and becomes in a state where it may transition from the wake-up state to the sleep state, so the cutoff condition of the slave ECU 3 is satisfied.

[0048] In this embodiment, the cutoff condition of the slave ECU 3 includes a voltage drop condition. In other words, the cutoff conditions of the slave ECUs 4 and 5 do not include the voltage drop condition. The voltage drop condition is that the battery voltage of the battery 7 becomes less than a preset cutoff determination value. That is, when the battery voltage of the battery 7 becomes less than the cutoff determination value, the cutoff condition is satisfied.

[0049] Here, when the cutoff condition is not satisfied, the CPU 41 ends the state transition process. On the other hand, when the cutoff condition is satisfied, the CPU 41 transmits, at S20, an end notification indicating that the relay connected to its own node may be set to the cutoff state to the master ECU 2. When receiving the end notification, the master ECU 2 sets the relay corresponding to the received end notification to the cutoff state, for example, after a preset standby time has elapsed for the slave ECU that is the source of the end notification. This standby time is set for each slave ECU so as to be longer than the time required for the slave ECU to execute various processes before transitioning to the sleep state, transition its own node to the sleep state after the various processes are completed, and until the transition to the sleep state is completed. For example, when receiving an end notification from the slave ECU 3, the master ECU 2 sets the relay 15 to the cutoff state after a preset standby time has elapsed for the slave ECU 3.

[0050] At S30, the CPU 41 starts a reception timer provided in the RAM 43. The reception timer is, for example, a timer that increments every 1 ms, and when started, its value increments from 0 (that is, 1 is added).

[0051] At S40, the CPU 41 determines whether a CAN frame addressed to its own node has been received. Here, when a CAN frame addressed to its own node has been received, the CPU 41 ends the state transition process. On the other hand, when a CAN frame addressed to its own node has not been received, the CPU 41 determines, at S50, whether a preset reception determination time has elapsed. Specifically, the CPU 41 determines whether the value of the reception timer is equal to or greater than the value corresponding to the reception determination time.

[0052] Here, if the reception determination time has not elapsed, the CPU 41 proceeds to S40. On the other hand, if the reception determination time has elapsed, the CPU 41 executes various end processes before shifting to the sleep state at S60, and after the various end processes are completed, it shifts its own node to the sleep state.

[0053] The CPU 41 determines at S70 whether a CAN frame has been received. Note that at S70, the CPU 41 determines that a CAN frame has been received even when a CAN frame addressed not only to its own node but also to other nodes has been received.

[0054] Here, if no CAN frame has been received, the CPU 41 waits until a CAN frame is received by repeating the process at S70. Then, when a CAN frame is received, the CPU 41 activates its own node at S80 (i.e., shifts its own node to the wake-up state) and ends the state transition process.

[0055] The slave ECUs 3, 4, and 5 configured in this way are each configured to receive power supply from the battery 7 via relays 15, 16, and 17 that are configured to switch between a conduction state in which the power supply path is conducted and a cutoff state in which the power supply path is cut off.

[0056] The slave ECUs 3, 4, and 5 are each configured to transmit an end notification to the master ECU 2 when a preset cutoff condition indicating that the relays 15, 16, and 17 connected to the slave ECUs 3, 4, and 5 may be put in the cutoff state is satisfied. The master ECU 2 is configured to be connected to the slave ECUs 3, 4, and 5 so as to enable data communication therebetween, to be configured to be able to transmit and receive CAN frames, and to control the operation of the relays 15, 16, and 17.

[0057] After the interruption condition is satisfied, each of the slave ECUs 3, 4, and 5 is configured to shift to the sleep state when it does not receive CAN frames addressed to its own node from all of a plurality of communication devices (i.e., the master ECU 2 and the slave ECUs 3, 4, and 5) that are communicably connected to the slave ECUs 3, 4, and 5 before a preset reception determination time elapses.

[0058] Even when a failure occurs in which the master ECU 2 that has received the termination notification from the slave ECUs 3, 4, and 5 cannot switch the relays 15, 16, and 17 to the cutoff state while attempting to switch the relays 15, 16, and 17 to the cutoff state, each of the slave ECUs 3, 4, and 5 can be shifted to the sleep state. For this reason, even though the relays 15, 16, and 17 may be in a state where they can be cut off to stop the operation of the slave ECUs 3, 4, and 5, the situation where the relays 15, 16, and 17 are in the conducting state and the slave ECUs 3, 4, and 5 are in the wake-up state continues, and the slave ECUs 3, 4, and 5 wastefully consume power can be suppressed, and power consumption in the communication system 1 can be reduced.

[0059] Each of the slave ECUs 3, 4, and 5 is configured to shift to the wake-up state when it receives a CAN frame from at least one of one or more communication devices (i.e., at least one of the master ECU 2 and the slave ECUs 3, 4, and 5) when the slave ECUs 3, 4, and 5 are in the sleep state. Thereby, each of the slave ECUs 3, 4, and 5 can shift to the wake-up state when it becomes necessary to cause the slave ECUs 3, 4, and 5 to execute various processes, and can promptly execute the necessary various processes on the slave ECUs 3, 4, and 5.

[0060] When the slave ECUs 3, 4, and 5 do not receive a CAN frame addressed to the slave ECUs 3, 4, and 5 respectively, they shift to the sleep state. As a result, the slave ECUs 3, 4, and 5 can suppress the occurrence of a situation where they cannot shift to the sleep state by receiving a CAN frame addressed to a node other than their own node (i.e., another node), and the power consumption in the communication system 1 can be further reduced.

[0061] The cutoff condition of the slave ECU 3 includes a voltage drop condition indicating that the battery voltage of the battery 7 becomes less than a preset cutoff determination value. Thereby, when the battery voltage becomes low, the slave ECU 3 can shift the slave ECU 3 that executes less important processing to the sleep state. For this reason, the slave ECU 3 can suppress the occurrence of a situation where when the battery voltage becomes low, the battery voltage further decreases due to the execution of less important processing, and the slave ECUs 4 and 5 cannot execute highly important processing.

[0062] Also, the communication system 1 includes the slave ECUs 3, 4, and 5 and the master ECU 2. The slave ECUs 3, 4, and 5 each receive power supply from the battery 7 via relays 15, 16, and 17 configured to switch between a conducting state in which a power supply path is made conductive and a cutoff state in which the power supply path is cut off. The master ECU 2 is connected to be capable of data communication with the slave ECUs 3, 4, and 5, is configured to be capable of transmitting and receiving CAN frames, and is configured to control the operation of the relays 15, 16, and 17.

[0063] When a preset cutoff condition indicating that the relays 15, 16, and 17 connected to the slave ECUs 3, 4, and 5 can be set to the cutoff state is satisfied, the slave ECUs 3, 4, and 5 are each configured to transmit an end notification to the master ECU 2.

[0064] After the interruption condition is satisfied, when the slave ECUs 3, 4, and 5 do not receive CAN frames addressed to their own nodes from all of the plurality of communication devices (i.e., the master ECU 2 and the slave ECUs 3, 4, and 5) that are communicably connected to the slave ECUs 3, 4, and 5 before the preset reception determination time elapses, the slave ECUs 3, 4, and 5 are configured to shift to the sleep state.

[0065] Since such a communication system 1 is a system including the slave ECUs 3, 4, and 5, effects similar to those of the slave ECUs 3, 4, and 5 can be obtained. In the embodiment described above, the relays 15, 16, and 17 correspond to the power supply switching unit, the battery 7 corresponds to the power supply, the slave ECUs 3, 4, and 5 correspond to the electronic control unit and the first control unit, the CAN frame corresponds to the communication frame, and the master ECU 2 corresponds to the power supply control device and the second control device.

[0066] Also, S10 and S20 correspond to the processing as the end notification unit, S30 to S60 correspond to the processing as the sleep transition unit, and S70 to S80 correspond to the processing as the wake-up transition unit.

[0067] [Second Embodiment] The second embodiment of the present disclosure will be described below with reference to the drawings. In the second embodiment, differences from the first embodiment will be described. The same reference numerals are given to the common configurations.

[0068] The communication system 1 of the second embodiment is different from the first embodiment in that the state transition process is changed and the master ECU 2 executes the state transmission process. Next, the procedure of the state transmission process executed by the control unit 11 of the master ECU 2 will be described. The state transmission process is a process that is repeatedly executed during the operation of the master ECU 2.

[0069] When the status transmission process is executed, as shown in FIG. 3, the CPU 21 of the control unit 11 checks, for each of the relays 15, 16, and 17, whether it is in the on state (i.e., the conductive state) or the off state (i.e., the cut-off state) at S110. Specifically, the CPU 21 first detects the value of the current flowing through the power supply path where the relays 15, 16, and 17 are arranged (hereinafter referred to as the relay current value). Then, when the detected relay current value is equal to or greater than a preset on-determination value, the CPU 21 determines that the corresponding relay is in the on state, and when the detected relay current value is less than the on-determination value, the CPU 21 determines that the corresponding relay is in the off state.

[0070] At S120, based on the confirmation result at S110, the CPU 21 transmits power supply switching state information indicating whether each of the relays 15, 16, and 17 is in the on state or the off state to the slave ECUs 3 to 5, and ends the status transmission process.

[0071] Next, the procedure of the state transition process of the second embodiment will be described. When the state transition process of the second embodiment is executed, as shown in FIG. 4, the CPU 41 of the control unit 31 determines at S210 whether it has received the power supply switching state information from the master ECU 2.

[0072] Here, if the power supply switching state information has not been received, the CPU 41 ends the state transition process. On the other hand, if the power supply switching state information has been received, the CPU 41 determines at S220 whether all the relays (i.e., the relays 15, 16, and 17) are in the off state based on the received power supply switching state information. Here, if all of the relays 15, 16, and 17 are in the off state, the CPU 41 proceeds to S240.

[0073] On the other hand, when at least one of the relays 15, 16, and 17 is in the ON state, the CPU 41 determines at S230 whether all relays other than the relay of its own node are in the OFF state. For example, when the own node is the slave ECU 3, if the relay 15 is in the ON state and the relays 16 and 17 are in the OFF state, the CPU 41 determines that all relays other than the relay of its own node are in the OFF state.

[0074] Here, if there is a relay in the ON state other than the relay of its own node, the CPU 41 ends the state transition process. On the other hand, if all relays other than the relay of its own node are in the OFF state, the CPU 41 proceeds to S240.

[0075] When proceeding to S240, the CPU 41 shifts its own node to the sleep state and ends the state transition process. Each of the slave ECUs 3, 4, and 5 configured in this way is configured to receive power supply from the battery 7 via the relays 15, 16, and 17 which are configured to switch between a conduction state for conducting the power supply path and a cutoff state for cutting off the power supply path.

[0076] When the slave ECUs 3, 4, and 5 receive the power supply switching state information from the master ECU 2, based on the received power supply switching state information, when all of the relays 15, 16, and 17 are in the cutoff state, or when all relays other than the relays connected to the slave ECUs 3, 4, and 5 among the relays 15, 16, and 17 are in the cutoff state, the slave ECUs 3, 4, and 5 are configured to shift to the sleep state. The master ECU 2 is connected to be capable of data communication with the slave ECUs 3, 4, and 5 and is configured to control the operation of the relays 15, 16, and 17. The power supply switching state information indicates whether each of the relays 15, 16, and 17 is in the conduction state or the cutoff state.

[0077] Even when the slave ECUs 3, 4, and 5 are in an abnormal state where all of the relays 15, 16, and 17 are in the off state or all relays other than the relays 15, 16, and 17 connected to the slave ECUs 3, 4, and 5 are in the off state, the operation of the slave ECUs 3, 4, and 5 can be continued, and the situation where the slave ECUs 3, 4, and 5 wastefully consume power can be suppressed, thereby reducing power consumption in the communication system 1. Note that the state where all of the relays 15, 16, and 17 are in the off state and the state where only one of the relays 15, 16, and 17 is in the on state can only occur due to a failure.

[0078] The communication system 1 also includes relays 15, 16, and 17, slave ECUs 3, 4, and 5, and a master ECU 2. The relays 15, 16, and 17 are configured to switch between an on state in which a power supply path is made conductive and an off state in which the power supply path is interrupted. Each of the slave ECUs 3, 4, and 5 receives power supply from the battery 7 via the relays 15, 16, and 17. The master ECU 2 is connected to be capable of data communication with the slave ECUs 3, 4, and 5 and is configured to control the operation of the relays 15, 16, and 17.

[0079] The master ECU 2 is configured to transmit power supply switching state information indicating whether each of the relays 15, 16, and 17 is in the on state or the off state to the slave ECUs 3, 4, and 5.

[0080] Each of the slave ECUs 3, 4, and 5 is configured to shift to the sleep state when all of the relays 15, 16, and 17 are in the off state or when all relays other than the relays connected to the slave ECU among the relays 15, 16, and 17 are in the off state, based on the power supply switching state information received from the master ECU 2.

[0081] Since such a communication system 1 is a system including the slave ECUs 3, 4, and 5, the same effects as those of the slave ECUs 3, 4, and 5 can be obtained. In the embodiments described above, relays 15, 16, and 17 correspond to a plurality of power supply switching units, S120 corresponds to the processing as a state information transmission unit, and S220 to S240 correspond to the processing as a cut-off transition unit.

[0082] [Third Embodiment] The third embodiment of the present disclosure will be described below with reference to the drawings. In the third embodiment, the parts different from the first embodiment will be described. The same reference numerals are given to the common configurations.

[0083] As shown in FIG. 5, the communication system 1 of the third embodiment is different from the first embodiment in that it includes a first battery 51 and a second battery 52 instead of the battery 7. The first battery 51 supplies power to the slave ECUs 3, 4, and 5 via the relays 15, 16, and 17 with a DC battery voltage.

[0084] The second battery 52 supplies power to the slave ECUs 3, 4, and 5 via the relays 15, 16, and 17 with a DC battery voltage. The master ECU 2 includes a first disconnection detection function for detecting whether a disconnection has occurred in the power supply path from the first battery 51 to the relays 15, 16, and 17, and a second disconnection detection function for detecting whether a disconnection has occurred in the power supply path from the second battery 52 to the relays 15, 16, and 17. For example, the disconnection occurrence location P1 in FIG. 5 indicates that a disconnection has occurred in the power supply path from the first battery 51 to the relays 15, 16, and 17.

[0085] In addition, the communication system 1 of the third embodiment is different from the first embodiment in that the state transition process of the slave ECU 3 is changed. The state transition process of the slave ECU 3 in the third embodiment is different from the first embodiment in that the cut-off condition of S10 is changed.

[0086] That is, in the state transition process of the third embodiment, the CPU 41 determines, at S10, whether or not the cutoff condition of the third embodiment is satisfied. The cutoff condition of the third embodiment includes a power supply failure condition, which will be described later, in addition to the cutoff condition of the first embodiment. That is, when at least one of the cutoff condition of the first embodiment and the power supply failure condition, which will be described later, is satisfied, the cutoff condition of the third embodiment is satisfied. The power supply failure condition is that a disconnection of the power supply path has been detected by the above-described first disconnection detection function and the above-described second disconnection detection function. Thus, in the slave ECU 3, the reason for including the power supply failure condition in the cutoff condition is that the slave ECU 3 is executing a process with a low importance level.

[0087] Here, when the cutoff condition is not satisfied, the CPU 41 ends the state transition process. On the other hand, when the cutoff condition is satisfied, the CPU 41 proceeds to S20. Note that in the present embodiment, the state transition process executed by the slave ECUs 4 and 5 does not include the power supply failure condition at S10.

[0088] The cutoff condition of the slave ECU 3 configured as described above includes a power supply failure condition indicating that a failure has occurred in the power supply from the first battery 51 and the second battery 52 to the slave ECUs 3, 4, and 5. Thereby, when the power supply capacity to the slave ECUs 3, 4, and 5 decreases, the slave ECU 3 can shift the slave ECU 3, which executes a process with a low importance level, to the sleep state. For this reason, when the power supply capacity decreases, the slave ECU 3 can suppress the occurrence of a situation in which the execution of a process with a low importance level further reduces the power supply capacity and the slave ECUs 4 and 5 cannot execute a process with a high importance level.

[0089] In the embodiment described above, the first battery 51 and the second battery 52 correspond to the power supply. [Fourth Embodiment] The fourth embodiment of the present disclosure will be described below with reference to the drawings. In the fourth embodiment, the parts different from the first embodiment will be described. The same reference numerals are given to the common configurations.

[0090] As shown in FIG. 7, the communication system 1 according to the fourth embodiment is different from the first embodiment in that a smart sensor 501, a smart actuator 502, a wireless device 503, and relays 504 and 505 are added.

[0091] The smart sensor 501 is a sensor having a communication function. The smart sensor 501 is connected to the communication bus 8. The smart actuator 502 is an actuator having a communication function. The smart actuator 502 is connected to the communication bus 8.

[0092] The wireless device 503 is a wireless communication device for performing wireless communication with an external communication device installed outside the vehicle. The wireless device 503 is, for example, a DCM. DCM is an abbreviation for Data Communication Module.

[0093] The relay 504 is disposed on the power supply path between the battery 7 and the smart sensor 501. The relay 505 is disposed on the power supply path between the battery 7 and the smart actuator 502.

[0094] Each of the relays 504 and 505 is configured to switch to either a conduction state in which the power supply path is conducted or a cutoff state in which the power supply path is cut off according to a command from the control unit 11. Hereinafter, the master ECU 2, the slave ECUs 3 to 6, the smart sensor 501, and the smart actuator 502 are collectively referred to as nodes.

[0095] (Prerequisite conditions) The master ECU 2 and the slave ECU 6 are always powered from the battery 7 without passing through a relay and can switch to a wake-up state or a sleep state independently of their own nodes. Hereinafter, the master ECU 2 and the slave ECU 6 are also referred to as NM-mounted nodes. An NM-mounted node is a node having a function of generating an NM frame.

[0096] Slave ECUs 3 to 5, smart sensor 501, and smart actuator 502 are powered via relays and cannot switch between the wake-up state and the sleep state on their own nodes. That is, they enter the wake-up state when the relay is turned on and enter the sleep state when the relay is turned off. Hereinafter, slave ECUs 3 to 5, smart sensor 501, and smart actuator 502 are also referred to as NM non-mounted nodes. An NM non-mounted node is a node that does not have the function of generating and interpreting NM frames.

[0097] An NM non-mounted node includes at least one of an actuator and a sensor in addition to an ECU having a control function. The power supply paths of the NM non-mounted nodes are respectively connected to relays 15, 16, 17, 504, and 505 of the master ECU 2.

[0098] The NM non-mounted node and the relay may be connected one-to-one, or a plurality of NM non-mounted nodes belonging to the same cluster (that is, a group that starts up simultaneously) may be connected under one relay.

[0099] The master ECU 2 and the NM-mounted nodes have a CAN communication unit and can transmit and receive NM frames. The NM-mounted node determines whether its own node is in the wake-up state or the sleep state based on the NM frames transmitted and received via the communication bus.

[0100] The master ECU 2 turns on or off relays 15, 16, 17, 504, and 505 to which the NM non-mounted nodes are connected based on the NM frames transmitted and received via the communication bus.

[0101] In the payload (that is, the data area) of the NM frames transmitted and received by the master ECU 2 and the NM-mounted nodes, information indicating which cluster is to be activated is stored in one or more bits.

[0102] One or more master ECUs (i.e., ECUs with built-in relays) are installed in the vehicle. As shown in FIG. 8, one or more nodes belonging to each cluster are determined in advance by the system developer. It is also possible to assign a cluster 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), the cluster wakes up. In the case of the master ECU, waking up means turning on the relay.

[0103] (First startup case) The first startup case is an operation example of diagnosing the failure of slave ECU 3 at the request from the cloud.

[0104] First, a connection request comes from the base station (i.e., the cloud) side to the vehicle radio 503. Next, when the radio 503 determines that it is a valid connection, it transmits the event received from the cloud to the master ECU 2.

[0105] Next, the master ECU 2 determines the service of "diagnosing the failure of slave ECU 3" based on the event, and generates an NM frame that enables the bit of the third cluster to which only the slave ECU 3 belongs in order to start the slave ECU 3.

[0106] Next, the master ECU 2 transmits the generated NM frame onto the communication buses 8 and 9. Since there is no NM-mounted node belonging to the third cluster on the communication buses 8 and 9, there is no change in the devices on the communication bus.

[0107] Next, the master ECU 2, at the same time as above, executes processing based on the NM frame in the control unit 11 as if it has received the NM frame with the bit of the third cluster enabled. Next, when the control unit 11 of the master ECU 2 determines a wake-up instruction to the third cluster based on the NM frame, since the relay 15 is included in the third cluster, the relay 15 is turned on.

[0108] When relay 15 is turned on, power is supplied to the downstream slave ECU 3 to start it up. The master ECU 2 waits for the slave ECU 3 to start up, requests a diagnostic code from the slave ECU 3, and transmits the response result from the slave ECU 3 to the base station via the radio 503.

[0109] (Second startup case) The second startup case is an operation example of diagnosing the failure of the slave ECU 6 at the request from the cloud.

[0110] First, a connection request comes from the base station (i.e., the cloud) side to the vehicle radio 503. Next, when the radio 503 determines it as a valid connection, it conveys the event received from the cloud to the master ECU 2.

[0111] Next, the master ECU 2 determines a service of "diagnosing the failure of the slave ECU 6" based on the event, and generates an NM frame with the bits of the fourth cluster to which only the slave ECU 6 belongs enabled to start up the slave ECU 6.

[0112] Next, the master ECU 2 transmits the generated NM frame onto the communication buses 8, 9. Since the slave ECU 6 is on the communication bus 9 as a node belonging to the fourth cluster, the slave ECU 6 wakes up.

[0113] Next, the master ECU 2, at the same time as above, the control unit 11 executes processing based on the NM frame assuming that it has received the NM frame with the bits of the fourth cluster enabled. Next, even if the control unit 11 of the master ECU 2 determines a wake-up instruction to the fourth cluster based on the NM frame, since the corresponding relay is not included in the fourth cluster, it is ignored.

[0114] When the slave ECU 6 is activated, the master ECU 2 requests diagnostic codes from the slave ECU 6 via the communication bus and transmits the response result from the slave ECU 6 to the base station via the radio 503.

[0115] (Third startup case) The third startup case is an example of an operation where the user activates the remote air conditioner with a smartphone. First, the user instructs the in-vehicle air conditioner to turn on from the smartphone.

[0116] When the radio 503 receives the instruction signal from the smartphone and determines that the instruction signal is valid, it transmits the event received from the cloud (i.e., the instruction signal) to the master ECU 2.

[0117] Based on the event, the master ECU 2 determines "air conditioning service" and generates an NM frame that activates the second cluster as the air conditioning cluster. The master ECU 2 periodically transmits the generated NM frame to the communication buses 8 and 9 until an air conditioner stop instruction is issued. If you want to continue the active state, it is necessary to keep transmitting the NM frame periodically. At the same time, the control unit 11 of the master ECU 2 executes processing based on the NM frame.

[0118] When an NM frame that activates the second cluster appears on the communication bus 9, the slave ECU 6 (i.e., the air conditioner ECU) belonging to the second cluster receives the NM frame and wakes up according to the received NM frame.

[0119] When the control unit 11 of the master ECU 2 detects that the second cluster is active, it turns on the relays 504 and 505 belonging to the second cluster. When the relays 504 and 505 are turned on, power is supplied to the smart sensor 501 (i.e., the temperature sensor) and the smart actuator 502 (i.e., the compressor).

[0120] As described above, power supply to the air conditioner ECU, the smart sensor 501, and the smart actuator 502 starts, and it becomes possible to turn on the in-vehicle air conditioner. When the user instructs to turn off the in-vehicle air conditioner from the smartphone, the master ECU 2 stops the periodic transmission of the NM frame.

[0121] When the NM frame is interrupted, the slave ECU 6 transitions to the sleep state, and the master ECU 2 turns off the relays 504 and 505. As a result, the in-vehicle air conditioner stops.

[0122] (Fourth startup case) The fourth startup case is an operation example of starting the in-vehicle air conditioner from the slave ECU 6. Since power is always supplied to the slave ECU 6 even when the vehicle is stopped, even while in the sleep state, the slave ECU 6 can detect the input of a signal indicating that the start switch connected to the slave ECU 6 has been turned on and wake up.

[0123] The awakened slave ECU 6 generates an NM frame with the bit corresponding to the second cluster turned on after confirming the input to start the in-vehicle air conditioner. The slave ECU 6 transmits the generated NM frame via the CAN communication unit 32. When the master ECU 2 receives this NM frame, the master ECU 2 turns on the relays 504 and 505 belonging to the second cluster.

[0124] When the start switch of the in-vehicle air conditioner is turned off, the slave ECU 6 stops transmitting the NM frame and then transitions to the sleep state after a while. When the NM frame is interrupted, the master ECU 2 turns off the relays 504 and 505 after a while and ends the control.

[0125] When the master ECU 2 determines that control needs to continue even after the transmission of the NM frame has stopped, the master ECU 2 transmits an NM frame with the bit corresponding to the second cluster turned on. As a result, the slave ECU 6 and the relays 504 and 505 can also maintain their activated states until the transmission of the NM frame generated by the master ECU 2 stops.

[0126] [Fifth Embodiment] The fifth embodiment of the present disclosure will be described below with reference to the drawings. In the fifth embodiment, the parts different from the first embodiment will be described.

[0127] The communication system 100 of the fifth embodiment is mounted on a vehicle and, as shown in FIG. 9, includes a central ECU 101, upstream power distribution units 102 and 103, zone ECUs 104, 105, 106, and 107, slave ECUs 108, 109, 110, 111, 112, 113, 114, 115, 116, a battery 117, and a slave ECU 118. Hereinafter, the central ECU 101, the zone ECUs 104 to 107, and the slave ECUs 108 to 116 and 118 are collectively referred to as nodes. Here, the zone ECU may be an ECU that bundles slave ECUs located in a predetermined area within the vehicle or an ECU that bundles slave ECUs belonging to a predetermined domain.

[0128] The battery 117 supplies power to each part of the vehicle with a DC battery voltage (for example, 12V). The central ECU 101, the upstream power distribution units 102 and 103, the zone ECUs 104 to 107, and the slave ECUs 108 to 116 and 118 operate by receiving power supply from the battery 117.

[0129] The upstream power distribution unit 102 receives power supply from the battery 117 through a power supply path 121 between the battery 117 and the upstream power distribution unit 102. The upstream power distribution unit 103 receives power supply from the battery 117 through a power supply path 122 between the battery 117 and the upstream power distribution unit 103.

[0130] The zone ECUs 104 and 105 each receive power supply from the battery 117 through the power supply paths 123 and 124 between the upstream power distribution unit 102 and the zone ECUs 104 and 105.

[0131] The zone ECUs 106 and 107 each receive power supply from the battery 117 through the power supply paths 125 and 126 between the upstream power distribution unit 103 and the zone ECUs 106 and 107.

[0132] The slave ECUs 108 and 109 each receive power supply from the battery 117 through the power supply paths 127 and 128 between the zone ECU 104 and the slave ECUs 108 and 109.

[0133] The slave ECUs 110 and 111 each receive power supply from the battery 117 through the power supply paths 129 and 130 between the zone ECU 105 and the slave ECUs 110 and 111.

[0134] The slave ECUs 112, 113, and 114 each receive power supply from the battery 117 through the power supply paths 131, 132, and 133 between the zone ECU 106 and the slave ECUs 112, 113, and 114.

[0135] The slave ECUs 115 and 116 each receive power supply from the battery 117 through the power supply paths 134 and 135 between the zone ECU 107 and the slave ECUs 115 and 116.

[0136] The slave ECU 118 receives power supply from the battery 117 through the power supply path 136. The central ECU 101 and the upstream power distribution unit 102 are connected to each other so as to be capable of data communication via the communication line 141.

[0137] The central ECU 101 and the upstream power distribution unit 103 are connected to each other so as to be capable of data communication via the communication line 142. The central ECU 101 and the zone ECUs 104, 105, 106, 107 are respectively connected to be capable of data communication with each other via communication lines 143, 144, 145, 146.

[0138] The zone ECU 104 and the slave ECUs 108, 109, 118 are connected to be capable of data communication with each other via a communication bus 147. The zone ECU 105 and the slave ECUs 110, 111 are connected to be capable of data communication with each other via a communication bus 148.

[0139] The zone ECU 106 and the slave ECUs 112, 113, 114 are connected to be capable of data communication with each other via a communication bus 149. The zone ECU 107 and the slave ECUs 115, 116 are connected to be capable of data communication with each other via a communication bus 150.

[0140] As shown in FIG. 10, the central ECU 101 includes a control unit 151, communication units 152, 153, 154, 155, 156, 157, and a storage unit 158. The control unit 151 is an electronic control device mainly configured around a microcomputer including a CPU 161, a ROM 162, a RAM 163, etc. Various functions of the microcomputer are realized by the CPU 161 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 162 corresponds to the non-transitory tangible recording medium storing the program. Also, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 161 may be configured hardware-wise by one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control unit 151 may be one or a plurality.

[0141] The communication unit 152 communicates by transmitting and receiving communication frames to and from an upstream power distribution unit 102 connected to the communication line 141, for example, based on the Ethernet communication protocol. Ethernet is a registered trademark.

[0142] The communication unit 153 communicates by transmitting and receiving communication frames to and from the upstream power distribution unit 103 connected to the communication line 142, for example, based on the Ethernet communication protocol. The communication unit 154 communicates by transmitting and receiving communication frames to and from the zone ECU 104 connected to the communication line 143, for example, based on the Ethernet communication protocol.

[0143] The communication unit 155 communicates by transmitting and receiving communication frames to and from the zone ECU 105 connected to the communication line 144, for example, based on the Ethernet communication protocol. The communication unit 156 communicates by transmitting and receiving communication frames to and from the zone ECU 106 connected to the communication line 145, for example, based on the Ethernet communication protocol.

[0144] The communication unit 157 communicates by transmitting and receiving communication frames to and from the zone ECU 107 connected to the communication line 145, for example, based on the Ethernet communication protocol. The storage unit 158 is a storage device for storing various data. The storage unit 158 stores the startup table 165 described later.

[0145] The upstream power distribution unit 102 includes a control circuit 171, a communication unit 172, and electronic fuses 173, 174. The control circuit 171 performs control to switch the electronic fuses 173, 174 between the on state and the off state based on an instruction acquired from the central ECU 101 via the communication unit 172.

[0146] The communication unit 172 communicates by transmitting and receiving communication frames to and from the central ECU 101 connected to the communication line 141, for example, based on the Ethernet communication protocol.

[0147] The electronic fuse 173 is disposed between the power supply path 121 and the power supply path 123. The electronic fuse 174 is disposed between the power supply path 121 and the power supply path 124. The upstream power distribution unit 103 includes a control circuit 181, a communication unit 182, and electronic fuses 183 and 184.

[0148] Based on an instruction acquired from the central ECU 101 via the communication unit 182, the control circuit 181 performs control to switch the electronic fuses 183 and 184 between an on state and an off state.

[0149] The communication unit 182 communicates with the central ECU 101 connected to the communication line 142 by transmitting and receiving communication frames based on, for example, the Ethernet communication protocol.

[0150] The electronic fuse 183 is disposed between the power supply path 122 and the power supply path 125. The electronic fuse 184 is disposed between the power supply path 122 and the power supply path 126. As shown in FIG. 11, the zone ECU 104 includes a control unit 191, a communication unit 192, a CAN communication unit 193, a storage unit 194, and electronic fuses 195 and 196.

[0151] The control unit 191 is an electronic control device mainly configured around a microcomputer including a CPU 201, a ROM 202, a RAM 203, and the like. Various functions of the microcomputer are realized by the CPU 201 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 202 corresponds to the non-transitory tangible recording medium storing the program. Further, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 201 may be configured hardware-wise by one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control unit 191 may be one or plural.

[0152] The communication unit 192 communicates with the central ECU 101 connected to the communication line 143 by transmitting and receiving communication frames based on, for example, the Ethernet communication protocol.

[0153] The CAN communication unit 193 communicates by transmitting and receiving communication frames based on the CAN communication protocol with the slave ECUs 108 and 109 connected to the communication bus 147.

[0154] The storage unit 194 is a storage device for storing various data. The electronic fuse 195 is disposed between the power supply path 123 and the power supply path 127. The electronic fuse 196 is disposed between the power supply path 123 and the power supply path 128.

[0155] The zone ECU 105 includes a control unit 211, a communication unit 212, a CAN communication unit 213, a storage unit 214, and electronic fuses 215 and 216. The control unit 211 is an electronic control device mainly configured around a microcomputer including a CPU 221, a ROM 222, a RAM 223, etc. Various functions of the microcomputer are realized by the CPU 221 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 222 corresponds to the non-transitory tangible recording medium storing the program. Further, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 221 may be configured hardware-wise by one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control unit 211 may be one or a plurality.

[0156] The communication unit 212 communicates by transmitting and receiving communication frames based on, for example, the Ethernet communication protocol with the central ECU 101 connected to the communication line 144.

[0157] The CAN communication unit 213 communicates by transmitting and receiving communication frames based on the CAN communication protocol with the slave ECUs 110 and 111 connected to the communication bus 148.

[0158] The storage unit 214 is a storage device for storing various data. The electronic fuse 215 is arranged between the power supply path 124 and the power supply path 129. The electronic fuse 216 is arranged between the power supply path 124 and the power supply path 130.

[0159] As shown in FIG. 12, the zone ECU 106 includes a control unit 231, a communication unit 232, a CAN communication unit 233, a storage unit 234, and electronic fuses 235, 236, and 237. The control unit 231 is an electronic control device mainly configured around a microcomputer including a CPU 241, a ROM 242, a RAM 243, and the like. Various functions of the microcomputer are realized by the CPU 241 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 242 corresponds to the non-transitory tangible recording medium storing the program. Further, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 241 may be configured hardware-wise by one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control unit 231 may be one or a plurality.

[0160] The communication unit 232 communicates by transmitting and receiving communication frames to and from the central ECU 101 connected to the communication line 145 based on, for example, the Ethernet communication protocol.

[0161] The CAN communication unit 233 communicates by transmitting and receiving communication frames to and from the slave ECUs 112, 113, and 114 connected to the communication bus 149 based on the CAN communication protocol.

[0162] The storage unit 234 is a storage device for storing various data. The electronic fuse 235 is arranged between the power supply path 125 and the power supply path 131. The electronic fuse 236 is arranged between the power supply path 125 and the power supply path 132. The electronic fuse 237 is arranged between the power supply path 125 and the power supply path 133.

[0163] The zone ECU 107 includes a control unit 251, a communication unit 252, a CAN communication unit 253, a memory unit 254, and electronic fuses 255 and 256. The control unit 251 is an electronic control device mainly configured around a microcomputer including a CPU 261, a ROM 262, a RAM 263, etc. Various functions of the microcomputer are realized by the CPU 261 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 262 corresponds to the non-transitory tangible recording medium storing the program. Also, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 261 may be configured hardware-wise by one or more ICs or the like. Also, the number of microcomputers constituting the control unit 251 may be one or more.

[0164] The communication unit 252 communicates by transmitting and receiving communication frames to and from the central ECU 101 connected to the communication line 146 based on, for example, the Ethernet communication protocol.

[0165] The CAN communication unit 253 communicates by transmitting and receiving communication frames to and from the slave ECUs 115 and 116 connected to the communication bus 150 based on the CAN communication protocol.

[0166] The memory unit 254 is a storage device for storing various data. The electronic fuse 255 is arranged between the power supply path 126 and the power supply path 134. The electronic fuse 256 is arranged between the power supply path 126 and the power supply path 135.

[0167] As shown in FIG. 13, the slave ECUs 108, 109, and 118 include a control unit 271, a CAN communication unit 272, and a memory unit 273. The control unit 271 is an electronic control device mainly composed of a microcomputer including a CPU 281, a ROM 282, a RAM 283, etc. Various functions of the microcomputer are realized by the CPU 281 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 282 corresponds to the non-transitory tangible recording medium storing the program. Also, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 281 may be configured hardware-wise by one or more ICs or the like. Also, the number of microcomputers constituting the control unit 271 may be one or more.

[0168] The CAN communication unit 272 communicates with the zone ECU 104 connected to the communication bus 147 based on the CAN communication protocol. The storage unit 273 is a storage device for storing various data.

[0169] The slave ECUs 110, 111 include a control unit 291, a CAN communication unit 292, and a storage unit 293. The control unit 291 is an electronic control device mainly composed of a microcomputer including a CPU 301, a ROM 302, a RAM 303, etc. Various functions of the microcomputer are realized by the CPU 301 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 302 corresponds to the non-transitory tangible recording medium storing the program. Also, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 301 may be configured hardware-wise by one or more ICs or the like. Also, the number of microcomputers constituting the control unit 291 may be one or more.

[0170] The CAN communication unit 292 communicates with the zone ECU 105 connected to the communication bus 148 based on the CAN communication protocol. The storage unit 293 is a storage device for storing various data.

[0171] The slave ECUs 112, 113, and 114 include a control unit 311, a CAN communication unit 312, and a storage unit 313. The control unit 311 is an electronic control device mainly configured around a microcomputer including a CPU 321, a ROM 322, a RAM 323, and the like. Various functions of the microcomputer are realized by the CPU 321 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 322 corresponds to the non-transitory tangible recording medium storing the program. Also, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 321 may be configured hardware-wise by one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control unit 311 may be one or a plurality.

[0172] The CAN communication unit 312 communicates with the zone ECU 106 connected to the communication bus 149 based on the CAN communication protocol. The storage unit 313 is a storage device for storing various data.

[0173] The slave ECUs 115 and 116 include a control unit 331, a CAN communication unit 332, and a storage unit 333. The control unit 331 is an electronic control device mainly configured around a microcomputer including a CPU 341, a ROM 342, a RAM 343, and the like. Various functions of the microcomputer are realized by the CPU 341 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 342 corresponds to the non-transitory tangible recording medium storing the program. Also, by executing this program, a method corresponding to the program is executed. Note that part or all of the functions executed by the CPU 341 may be configured hardware-wise by one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control unit 331 may be one or a plurality.

[0174] The CAN communication unit 332 communicates with the zone ECU 107 connected to the communication bus 150 based on the CAN communication protocol. The storage unit 333 is a storage device for storing various data.

[0175] As shown in FIG. 14, in the startup table 165 of the central ECU 101, a communication group (i.e., startup group) to be started is set for each event. In the startup table 165, a correspondence relationship between the startup group and the slave ECU to be put into the wake-up state is further set. In the startup table 165, a correspondence relationship between the slave ECU and the electronic fuse connected to the slave ECU is further set. Note that the startup table 165 may be set in a form in which it is possible to know the correspondence relationship of which zone ECU the slave ECU belongs to.

[0176] When the central ECU 101 detects the occurrence of an event, it determines the startup group by referring to the startup table 165 based on the detected event. When the central ECU 101 receives an NM frame, it determines that the communication group corresponding to the bit set to 1 in the received NM frame is the startup group.

[0177] The central ECU 101 starts the process of transmitting an NM frame indicating the startup group determined due to the detection of the occurrence of an event or the reception of an NM frame to the zone ECUs 104, 105, 106, 107. When the central ECU 101 starts transmitting the NM frame, it then periodically transmits the same NM frame.

[0178] The central ECU 101 refers to the startup table 165, and when it determines that an event has occurred or an NM frame has been received, it instructs to turn on the electronic fuses corresponding to the startup group and sends an electronic fuse control instruction to turn off the electronic fuses other than those corresponding to the startup group to the upstream power distribution units 102, 103 and the zone ECUs 104, 105, 106, 107.

[0179] Based on the received electronic fuse control instruction, the upstream power distribution unit 102 turns on or off the electronic fuses 173, 174. Based on the received electronic fuse control instruction, the upstream power distribution unit 103 turns on or off the electronic fuses 183, 184.

[0180] Based on the received electronic fuse control instruction, the zone ECU 104 turns on or off the electronic fuses 195, 196. Based on the received electronic fuse control instruction, the zone ECU 105 turns on or off the electronic fuses 215, 216.

[0181] Based on the received electronic fuse control instruction, the zone ECU 106 turns on or off the electronic fuses 235, 236, 237. Based on the received electronic fuse control instruction, the zone ECU 107 turns on or off the electronic fuses 255, 256.

[0182] Next, the procedure of the state transition process executed by the slave ECUs 108 to 116 will be described. The state transition process is a process that is repeatedly executed during the operation of the slave ECUs 108 to 116. Hereinafter, the procedure of the state transition process will be described by taking the slave ECU 108 as a representative.

[0183] When the state transition process is executed, the CPU 281 of the control unit 271 of the slave ECU 108 determines, as shown in FIG. 15, at S310 whether a preset cutoff condition is satisfied in the same manner as at S10.

[0184] Here, when the interruption condition is not satisfied, the CPU 281 ends the state transition process. On the other hand, when the interruption condition is satisfied, the CPU 281 transmits an end notification indicating that it may cut off the electronic fuse connected to its own node in S320 to the central ECU 101. Specifically, the CPU 281 transmits the end notification to the zone ECU 104. The zone ECU 104 transfers the end notification received from the CPU 281 of the slave ECU 108 to the central ECU 101.

[0185] When the central ECU 101 receives the end notification from the slave ECU 108, for example, after a preset standby time for the slave ECU 108 has elapsed, it transmits an electronic fuse control instruction to turn off the electronic fuse 195 to the zone ECU 104, thereby cutting off the electronic fuse 195.

[0186] The CPU 281 starts the reception timer provided in the RAM 283 in the same manner as in S30 at S330. The CPU 41 determines at S340 whether or not a CAN frame addressed to its own node has been received in the same manner as in S40. Here, when a CAN frame addressed to its own node has been received, the CPU 281 ends the state transition process. On the other hand, when a CAN frame addressed to its own node has not been received, the CPU 281 determines at S350 whether or not a preset reception determination time has elapsed in the same manner as in S50.

[0187] Here, when the reception determination time has not elapsed, the CPU 281 proceeds to S340. On the other hand, when the reception determination time has elapsed, the CPU 281 executes various end processes before transitioning to the sleep state in the same manner as in S60 at S360, and after the various end processes are completed, it transitions its own node to the sleep state.

[0188] The CPU 281 determines at S370 whether or not a CAN frame has been received in the same manner as in S70. Here, when the CAN frame is not received, the CPU 281 waits until the CAN frame is received by repeating the process of S370. When the CAN frame is received, the CPU 281 activates its own node in the same manner as in S80 at S380 and ends the state transition process.

[0189] The slave ECUs 108 to 116 configured as described above are each configured to receive power supply from the battery 117 via the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, and 256, which are configured to switch between a conductive state in which the power supply path is made conductive and a cutoff state in which the power supply path is cut off.

[0190] Each of the slave ECUs 108 to 116 is configured to send an end notification to the central ECU 101 when a preset cutoff condition indicating that the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, and 256 connected to the slave ECUs 108 to 116 may be set to the cutoff state is satisfied. The central ECU 101 is configured to be connected to the slave ECUs 108 to 116 so as to enable data communication, to be configured to be able to transmit and receive communication frames, and to be configured to control the operation of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, and 256.

[0191] After the cutoff condition is satisfied, each of the slave ECUs 108 to 116 is configured to shift to the sleep state when no CAN frame addressed to its own node is received from all of a plurality of communication devices (i.e., the central ECU 101, the zone ECUs 104 to 107, and the slave ECUs 108 to 116, 118) that are connected to the slave ECUs 108 to 116 so as to enable data communication before the preset reception determination time elapses.

[0192] Even if a failure occurs where the central ECU 101 that has received an end notification from the slave ECUs 108 to 116 cannot switch the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 to the off state when attempting to do so, the slave ECUs 108 to 116 can be shifted to the sleep state. For this reason, even though the slave ECUs 108 to 116 may be in a state where they can stop their operation by turning off the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256, the situation where the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 are in the conducting state and the slave ECUs 108 to 116 are in the wake-up state continues, and the slave ECUs 108 to 116 wastefully consume power can be suppressed, and power consumption in the communication system 100 can be reduced.

[0193] In the embodiment described above, the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 correspond to the power supply switching unit, the battery 117 corresponds to the power source, the slave ECUs 108 to 116 correspond to the electronic control device and the first control device, and the central ECU 101 corresponds to the power supply control device and the second control device.

[0194] Also, S310 and S320 correspond to the processing as the end notification unit, S330 to S360 correspond to the processing as the sleep transition unit, and S370 to S380 correspond to the processing as the wake-up transition unit.

[0195] Also, the slave ECUs 108 to 116 correspond to the slave control device, the zone ECUs 104 to 107 correspond to the zone control device, and the central ECU 101 corresponds to the central control device.

[0196] [Sixth Embodiment] The sixth embodiment of the present disclosure will be described below with reference to the drawings. In the sixth embodiment, parts different from the fifth embodiment will be described. The same reference numerals are assigned to the common configurations.

[0197] As shown in FIG. 16, the communication system 100 of the sixth embodiment is different from the fourth embodiment in that the configuration of the startup table 165 provided in the central ECU 101 is changed. That is, in the startup table 165 of the sixth embodiment, a startup group is set for each event. In other words, in the startup table 165 of the sixth embodiment, the correspondence between the startup group and the slave ECU to be put into the wake-up state is not set.

[0198] As shown in FIG. 17, the storage unit 194 of the zone ECU 104 is different from the fifth embodiment in that it further stores a startup table 205 to be described later. The storage unit 214 of the zone ECU 105 is different from the fifth embodiment in that it further stores a startup table 225 to be described later.

[0199] As shown in FIG. 18, the storage unit 234 of the zone ECU 106 is different from the fifth embodiment in that it further stores a startup table 245 to be described later. The storage unit 254 of the zone ECU 107 is different from the fifth embodiment in that it further stores a startup table 265 to be described later.

[0200] As shown in FIG. 16, for the slave ECUs 108, 109, 118 under the zone ECU 104, the startup table 205 sets the correspondence between the startup group and the slave ECU to be put into the wake-up state. The startup table 205 further sets the correspondence between the slave ECUs 108, 109, 118 and the electronic fuses connected to the slave ECUs 108, 109, 118.

[0201] The startup table 225 sets the correspondence between the startup group and the slave ECUs 110 and 111 to be woken up for the slave ECUs 110 and 111 under the zone ECU 105. The startup table 225 further sets the correspondence between the slave ECUs 110 and 111 and the electronic fuses connected to the slave ECUs 110 and 111.

[0202] The startup table 245 sets the correspondence between the startup group and the slave ECUs 112, 113, and 114 to be woken up for the slave ECUs 112, 113, and 114 under the zone ECU 106. The startup table 225 further sets the correspondence between the slave ECUs 112, 113, and 114 and the electronic fuses connected to the slave ECUs 112, 113, and 114.

[0203] The startup table 265 sets the correspondence between the startup group and the slave ECUs 115 and 116 to be woken up for the slave ECUs 115 and 116 under the zone ECU 107. The startup table 265 further sets the correspondence between the slave ECUs 115 and 116 and the electronic fuses connected to the slave ECUs 115 and 116.

[0204] When the central ECU 101 detects the occurrence of an event, it determines the startup group by referring to the startup table 165 based on the detected event. When the central ECU 101 receives an NM frame, it determines that the communication group corresponding to the bit set to 1 in the received NM frame is the startup group.

[0205] The central ECU 101 starts the process of transmitting an NM frame indicating the startup group determined due to the detection of the occurrence of an event or the reception of an NM frame to the zone ECUs 104, 105, 106, and 107. When the central ECU 101 starts transmitting the NM frame, it then periodically transmits the same NM frame.

[0206] When the zone ECUs 104, 105, 106, and 107 receive an NM frame, they transfer the received NM frame to the subordinate slave ECUs. Based on the received NM frame, the zone ECUs 104, 105, 106, and 107 refer to the activation tables 205, 225, 245, and 265, and for the subordinate slave ECUs, turn on the electronic fuses corresponding to the activation group indicated by the NM frame and turn off the electronic fuses other than those corresponding to the activation group.

[0207] Next, the procedure of the state transition process of the sixth embodiment will be described. As shown in FIG. 19, the state transition process of the sixth embodiment is different from the fifth embodiment in that the process of S325 is executed instead of S320.

[0208] That is, when the cutoff condition is satisfied in S310, the CPU 281 may send an end notification indicating that the electronic fuses connected to its own node may be set to the cutoff state in S325 to the zone ECU 104, and then proceeds to S330.

[0209] When the zone ECU 104 receives the end notification from the slave ECU 108, for example, after the preset standby time for the slave ECU 108 has elapsed, it sets the electronic fuse 195 to the cutoff state.

[0210] The slave ECUs 108 and 109 configured in this way are each configured to receive power supply from the battery 117 via the electronic fuses 195 and 196 that are configured to switch between a conduction state that conducts the power supply path and a cutoff state that cuts off the power supply path.

[0211] When a preset cutoff condition indicating that the electronic fuses 195 and 196 connected to the slave ECUs 108 and 109 may be cut off is satisfied, the slave ECUs 108 and 109 are each configured to send an end notification to the zone ECU 104. The central ECU 101 and the zone ECU 104 are connected to be capable of data communication with the slave ECUs 108 and 109, are configured to be able to transmit and receive communication frames, and are configured to control the operations of the electronic fuses 195 and 196.

[0212] After the cutoff condition is satisfied, each of the slave ECUs 108 and 109 is configured to shift to the sleep state when it does not receive CAN frames addressed to its own node from all of a plurality of communication devices (i.e., the central ECU 101, the zone ECUs 104 to 107, and the slave ECUs 108 to 116 and 118) that are connected to be capable of data communication with the slave ECUs 108 and 109 before a preset reception determination time elapses.

[0213] Even when a failure occurs in which the zone ECU 104 that has received the end notification from the slave ECUs 108 and 109 cannot switch the electronic fuses 195 and 196 to the cutoff state while attempting to switch the electronic fuses 195 and 196 to the cutoff state, the slave ECUs 108 and 109 can be shifted to the sleep state. For this reason, even though the slave ECUs 108 and 109 may be in a state where the operations of the slave ECUs 108 and 109 may be stopped by cutting off the electronic fuses 195 and 196, the situation where the slave ECUs 108 and 109 continue to consume power uselessly in a state where the electronic fuses 195 and 196 are in the conductive state and the slave ECUs 108 and 109 are in the wake-up state can be suppressed, and power consumption in the communication system 100 can be reduced.

[0214] Note that when a preset cutoff condition indicating that the electronic fuses 215 and 216 connected to the slave ECUs 110 and 111 may be cut off is satisfied, the slave ECUs 110 and 111 are each configured to send an end notification to the zone ECU 105.

[0215] Note that when a preset cutoff condition indicating that the electronic fuses 235, 236, and 237 connected to the slave ECUs 112, 113, and 114 may be cut off is satisfied, the slave ECUs 112, 113, and 114 are each configured to send an end notification to the zone ECU 106.

[0216] Note that when a preset cutoff condition indicating that the electronic fuses 255 and 256 connected to the slave ECUs 115 and 116 may be cut off is satisfied, the slave ECUs 115 and 116 are each configured to send an end notification to the zone ECU 107.

[0217] In the embodiment described above, the slave ECUs 108 to 116 correspond to the electronic control device and the first control device, the central ECU 101 and the zone ECUs 104 to 107 correspond to the power supply control device and the second control device, and S310 and S325 correspond to the processing as the end notification unit.

[0218] [Seventh Embodiment] The seventh embodiment of the present disclosure will be described below with reference to the drawings. In the seventh embodiment, the parts different from the fifth embodiment will be described. The same reference numerals are given to the common configurations.

[0219] The communication system 100 of the seventh embodiment is different from the fifth embodiment in that the state transition process is changed and the central ECU 101 executes the state transmission process. Next, the procedure of the state transmission process executed by the control unit 151 of the central ECU 101 will be described. The state transmission process is a process that is repeatedly executed during the operation of the central ECU 101.

[0220] When the status transmission process is executed, as shown in FIG. 20, the CPU 161 of the control unit 151 checks whether each of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 is in the on state or the off state at S410.

[0221] Specifically, the zone ECU 104 detects the value of the current flowing through the power supply path where the subordinate electronic fuses 195, 196 are arranged (hereinafter referred to as the relay current value). Then, when the detected relay current value is equal to or greater than a preset on-determination value, the zone ECU 104 determines that the corresponding relay is in the on state, and when the detected relay current value is less than the on-determination value, the zone ECU 104 determines that the corresponding relay is in the off state. Then, the zone ECU 104 transmits the electronic fuse status information indicating whether each of the subordinate electronic fuses 195, 196 is in the on state or the off state to the central ECU 101.

[0222] Similar to the zone ECU 104, the zone ECUs 105, 106, 107 detect the relay current value for the subordinate electronic fuses and transmit the electronic fuse status information indicating whether they are in the on state or the off state to the central ECU 101.

[0223] Based on the electronic fuse status information received from each of the zone ECUs 104, 105, 106, 107, the central ECU 101 checks whether each of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 is in the on state or the off state.

[0224] At S420, based on the confirmation result at S410, the CPU 161 transmits the power supply switching status information indicating whether each of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 is in the on state or the off state to the slave ECUs 108 to 116, and ends the status transmission process.

[0225] Next, the procedure of the state transition process of the seventh embodiment will be described. Hereinafter, the procedure of the state transition process will be described by taking the slave ECU 108 as a representative. When the state transition process is executed, as shown in FIG. 21, the CPU 281 of the control unit 271 of the slave ECU 108 determines whether or not power supply switching state information has been received from the central ECU 101 at S510.

[0226] Here, if the power supply switching state information has not been received, the CPU 281 ends the state transition process. On the other hand, if the power supply switching state information has been received, the CPU 281 determines at S520 whether or not all the electronic fuses (that is, electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256) are in the OFF state based on the received power supply switching state information. Here, if all the electronic fuses are in the OFF state, the CPU 281 proceeds to S540.

[0227] On the other hand, if at least one of all the electronic fuses is in the ON state, the CPU 281 determines at S530 whether or not all the electronic fuses other than the electronic fuses of its own node are in the OFF state.

[0228] Here, if there is an electronic fuse in the ON state other than the electronic fuses of its own node, the CPU 281 ends the state transition process. On the other hand, if all the electronic fuses other than the electronic fuses of its own node are in the OFF state, the CPU 281 proceeds to S540.

[0229] When proceeding to S540, the CPU 281 shifts its own node to the sleep state and ends the state transition process. The slave ECUs 108 to 116 configured as described above are each configured to receive power supply from the battery 117 via the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 which are configured to switch between a conduction state for conducting the power supply path and a cutoff state for cutting off the power supply path.

[0230] When slave ECUs 108 to 116 receive power supply switching state information from the central ECU 101, based on the received power supply switching state information, when all of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 are in the cut-off state, or when all of the electronic fuses other than the electronic fuses connected to the slave ECUs 108 to 116 among the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 are in the cut-off state, the slave ECUs 108 to 116 are configured to shift to the sleep state. The central ECU 101 is configured to be connected to the slave ECUs 108 to 116 so as to enable data communication and control the operations of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256. The power supply switching state information indicates whether each of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 is in the conducting state or the cut-off state.

[0231] Each of such slave ECUs 108 to 116 can suppress the occurrence of a situation where, even though all of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 are in the cut-off state or all of the electronic fuses other than the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 connected to the slave ECUs 108 to 116 are in the cut-off state, which is an abnormal state, the slave ECUs 108 to 116 continue to operate and the slave ECUs 108 to 116 waste power consumption, and can reduce power consumption in the communication system 100. Note that a state where all of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 are in the cut-off state and a state where only one of the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, 256 is in the conducting state can only occur due to a failure.

[0232] In the embodiments described above, the electronic fuses 195, 196, 215, 216, 235, 236, 237, 255, and 256 correspond to a plurality of power supply switching units, S420 corresponds to the processing as a state information transmission unit, and S520 to S540 correspond to the processing as a cut-off transition unit.

[0233] As described above, one embodiment of the present disclosure has been described. However, the present disclosure is not limited to the above embodiment and can be implemented with various modifications. [Modification Example 1] In the first to third embodiments described above, a form of controlling power supply using the relays 15, 16, and 17 has been shown. However, electronic fuses may be used instead of the relays 15, 16, and 17.

[0234] [Modification Example 2] In the first embodiment described above, a form of shifting to the sleep state when a CAN frame addressed to the own node is not received before the reception determination time elapses has been shown. However, when no CAN frame is received regardless of whether it is addressed to the own node or other nodes, the node may be shifted to the sleep state.

[0235] [Modification Example 3] In the first embodiment described above, a form of shifting the own node to the wake-up state when a CAN frame addressed not only to the own node but also to other nodes is received has been shown. However, when a CAN frame addressed to the own node is received, the own node may be shifted to the wake-up state. Thereby, the communication system 1 can reduce the frequency with which the own node shifts to the wake-up state when there is no need to execute various processes on the own node, and can further reduce power consumption in the communication system 1.

[0236] [Modification Example 4] In the second embodiment described above, a form of shifting the own node to the sleep state in the process of S240 has been shown. However, the own node may be shifted to the stop state in the process of S240. The stop state is an operating state in which functions that are also operating in the sleep state are stopped.

[0237] [Modification Example 5] In the above first embodiment, a form was shown in which an end notification is transmitted in S20 immediately after the cutoff condition is satisfied in S10. However, the end notification may be transmitted immediately before the process of S60 is performed.

[0238] [Modification Example 6] In the above fifth embodiment, a form was shown in which the slave ECUs 108 to 116 execute the state transition process. However, the zone ECUs 104 to 107 may execute the state transition process. For example, when the cutoff condition is satisfied, the zone ECU 104 transmits an end notification indicating that the electronic fuse 173 connected to its own node may be set in a cutoff state to the central ECU 101. Then, when the zone ECU 104 has not received a communication frame addressed to its own node until the reception determination time has elapsed, the zone ECU 104 shifts its own node to the sleep state. In this case, the zone ECUs 104 to 107 correspond to the first control device, the electronic fuses 173, 174, 183, and 184 correspond to the power supply switching unit, and the central ECU 101 corresponds to the second control device.

[0239] The control units 11 and 31 and their methods described in the present disclosure may be implemented by a dedicated computer configured by a processor and a memory programmed to execute one or more functions embodied by a computer program. Alternatively, the control units 11 and 31 and their methods described in the present disclosure may be implemented by a dedicated computer configured by a processor constituted by one or more dedicated hardware logic circuits. Or, the control units 11 and 31 and their methods described in the present disclosure may be implemented by one or more dedicated computers configured by a combination of a processor and a memory programmed to execute one or more functions and a processor constituted by one or more hardware logic circuits. Further, the computer program may be stored in a non-transitory tangible recording medium readable by a computer as instructions executable by the computer. The method for realizing the functions of each part included in the control units 11 and 31 does not necessarily include software, and all of its functions may be realized using one or more hardware.

[0240] A plurality of functions of one component in the above embodiment may be realized by a plurality of components, or one function of one component may be realized by a plurality of components. Also, a plurality of functions of a plurality of components may be realized by one component, or one function realized by a plurality of components may be realized by one component. Also, a part of the configuration of the above embodiment may be omitted. Also, at least a part of the configuration of the above embodiment may be added to or replaced with the configuration of another above embodiment.

[0241] In addition to the above-described ECUs 2 to 5, 101, and 104 to 116, the present disclosure can also be realized in various forms such as a system having the ECUs 2 to 5, 101, and 104 to 116 as components, a program for causing a computer to function as the ECUs 2 to 5, 101, and 104 to 116, a non-transitory physical recording medium such as a semiconductor memory storing this program, and a control method. [Technical idea disclosed in this specification] [Item 1] An electronic control device (3, 4, 5, 104 to 116) configured to receive power supply from a power source (7, 51, 52, 117) via a power supply switching unit (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conducting state for conducting a power supply path and a blocking state for blocking the power supply path, When a preset blocking condition indicating that the power supply switching unit connected to the electronic control device may be set to the blocking state is satisfied, an end notification unit (S10, S20, S310, S320, S325) configured to transmit an end notification to a power supply control device (2, 101 to 107) that is connected to be capable of data communication with the electronic control device, is configured to transmit and receive a communication frame, and is configured to control the operation of the power supply switching unit; After the blocking condition is satisfied, if all of one or more communication devices (2 to 5, 101 to 116, 118) that are connected to be capable of data communication with the electronic control device do not receive the communication frame before a preset reception determination time elapses, a sleep transition unit (S30 to S60, S330 to S360) configured to shift the electronic control device to a sleep state; An electronic control device comprising the above.

[0242] [Item 2] The electronic control device according to Item 1, When the electronic control device is in the sleep state, if the communication frame is received from at least one of one or more of the communication devices, a wake-up transition unit (S70 to S80, S370 to S380) configured to shift the electronic control device to a wake-up state.

[0243] [Item 3] The electronic control device according to Item 1 or Item 2, The sleep transition unit is an electronic control unit configured to transition to the sleep state when the communication frame addressed to the electronic control unit is not received.

[0244] [Item 4] The electronic control unit according to Item 2, wherein the wake-up transition unit is an electronic control unit configured to transition to the wake-up state when the communication frame addressed to the electronic control unit is received.

[0245] [Item 5] The electronic control unit according to any one of Items 1 to 4, wherein the cutoff condition includes a voltage drop condition indicating that the voltage value of the power supply becomes less than a preset cutoff determination value.

[0246] [Item 6] The electronic control unit according to any one of Items 1 to 5, wherein the cutoff condition includes a power supply failure condition indicating that a failure has occurred in the power supply from the power supply to the electronic control unit.

[0247] [Item 7] An electronic control unit (3, 4, 5, 104 to 116) configured to receive power supply from a power supply (7, 117) through at least one of a plurality of power supply switching units (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conducting state for conducting the power supply path and a cutoff state for cutting off the power supply path. A power supply control device (2, 101 to 107) that is connected to be capable of data communication with the electronic control device and is configured to control the operations of the plurality of power supply switching units receives power supply switching state information indicating whether each of the plurality of power supply switching units is in the conducting state or the blocking state. Based on the received power supply switching state information, when all of the plurality of power supply switching units are in the blocking state, or when all of the plurality of power supply switching units other than the power supply switching unit connected to the electronic control device among the plurality of power supply switching units are in the blocking state, an electronic control device including a transition unit during blocking (S220 to S240, S520 to S540) configured to shift the electronic control device to a stopped state or a sleep state.

[0248] [Item 8] A first control device (3, 4, 5, 104 to 116) that receives power supply from a power source (7, 51, 52, 117) via a power supply switching unit (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conducting state for conducting a power supply path and a blocking state for blocking the power supply path. A second control device (2, 101 to 107) that is connected to be capable of data communication with the first control device, is configured to be able to transmit and receive communication frames, and is configured to control the operation of the power supply switching unit. The first control device An end notification unit (S10, S20, S310, S320, S325) configured to transmit an end notification to the second control device when a preset blocking condition indicating that the power supply switching unit connected to the first control device may be set to the blocking state is satisfied. After the blocking condition is satisfied, if all of one or more communication devices (2 to 5, 101 to 116, 118) that are connected to be capable of data communication with the first control device do not receive the communication frame before a preset reception determination time elapses, a sleep transition unit (S30 to S60, S330 to S360) configured to shift the first control device to a sleep state. A communication system (1, 100) comprising

[0249] [Item 9] A plurality of power supply switching units (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conduction state for conducting a power supply path and a cutoff state for cutting off the power supply path; A first control device (3, 4, 5, 104 to 116) that receives power supply from a power source (7) via at least one of the plurality of power supply switching units; A second control device (2, 101 to 107) connected to be capable of data communication with the first control device and configured to control the operations of the plurality of power supply switching units. The second control device Includes a state information transmission unit (S120, S420) configured to transmit power supply switching state information indicating whether each of the plurality of power supply switching units is in the conduction state or the cutoff state to the first control device. The first control device Based on the power supply switching state information received from the second control device, when all of the plurality of power supply switching units are in the cutoff state, or when all of the plurality of power supply switching units other than the power supply switching units connected to the first control device are in the cutoff state, a communication system (1, 100) comprising a cutoff-time transition unit (S220 to S240, S520 to S540) configured to shift the first control device to a stop state or a sleep state.

[0250] [Item 10] The communication system (100) according to Item 8 or Item 9, The communication system Includes a slave control device (108 to 116) as the first control device, And includes a zone control device (104 to 107) connected to be capable of data communication with the slave control device and including the power supply switching units (195, 196, 215, 216, 235, 236, 237, 255, 256). including a central control device (101) configured to be connected to be capable of data communication with the zone control device and control the operation of the power supply switching unit as the second control device, a communication system in which the slave control device and the central control device are connected to be capable of data communication with each other via the zone control device.

[0251] [Item 11] The communication system (100) according to Item 8 or Item 9, wherein the communication system includes slave control devices (108 to 116) as the first control device, a zone control device (104 to 107) connected to be capable of data communication with the slave control device, including the power supply switching units (195, 196, 215, 216, 235, 236, 237, 255, 256), and configured to control the operation of the power supply switching units, and a central control device (101) connected to be capable of data communication with the zone control device as the second control device, a communication system in which the slave control device and the central control device are connected to be capable of data communication with each other via the zone control device.

[0252] [Item 12] The communication system (100) according to Item 8 or Item 9, wherein the communication system includes slave control devices (108 to 116), including a zone control device (104 to 107) connected to be capable of data communication with the slave control devices as the first control device, an upstream power supply distribution unit (102, 103) including the power supply switching units (173, 174, 183, 184), and a central control device (101) connected to be capable of data communication with the zone control device and the upstream power supply distribution unit as the second control device.

Explanation of Signs

[0253] 1… Communication system, 2… Master ECU, 3, 4, 5… Slave ECUs, 7… Battery, 15, 16, 17… Relays, 51… First battery, 52… Second battery, 100… Communication system, 101… Central ECU, 102, 103… Upstream power distribution units, 104~107… Zone ECUs, 108~116, 118… Slave ECUs, 117… Battery, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256… Electronic fuses

Claims

1. An electronic control device (3, 4, 5, 104 to 116) configured to receive power supply from a power source (7, 51, 52, 117) via a power supply switching unit (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conductive state for conducting a power supply path and a cut-off state for cutting off the power supply path, an end notification unit (S10, S20, S310, S320, S325) configured to transmit an end notification to a power supply control device (2, 101 to 107) that is connected to the electronic control device so as to be capable of data communication with the electronic control device, is configured to be capable of transmitting and receiving communication frames, and is configured to control an operation of the power supply switching unit, when a preset cut-off condition indicating that the power supply switching unit connected to the electronic control device may be set to the cut-off state is established; a sleep transition unit (S30 to S60, S330 to S360) configured to transition the electronic control device to a sleep state when the communication frame is not received from any of the one or more communication devices (2 to 5, 101 to 116, 118) connected to the electronic control device so as to be capable of data communication within a preset reception determination time after the interruption condition is established; An electronic control device comprising:

2. 2. The electronic control device according to claim 1, further comprising: An electronic control device comprising a wake-up transition unit (S70 to S80, S370 to S380) configured to transition the electronic control device to a wake-up state when the electronic control device receives the communication frame from at least one of the one or more communication devices while the electronic control device is in the sleep state.

3. 3. The electronic control device according to claim 1, The sleep transition unit transitions the electronic control device to the sleep state when the communication frame addressed to the electronic control device is not received.

4. 3. The electronic control device according to claim 2, The wake-up transition unit transitions the electronic control device to the wake-up state when the electronic control device receives the communication frame addressed to the electronic control device.

5. 3. The electronic control device according to claim 1, The shutoff condition includes a voltage drop condition indicating that a voltage value of the power supply falls below a preset shutoff determination value.

6. 3. The electronic control device according to claim 1, The electronic control device, wherein the shutoff condition includes a power supply fault condition indicating that a fault has occurred in the supply of power from the power source to the electronic control device.

7. An electronic control device (3, 4, 5, 104 to 116) configured to receive power supply from a power source (7, 117) via at least one of a plurality of power supply switching units (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conductive state for conducting a power supply path and a cut-off state for cutting off the power supply path, an electronic control device including a cut-off transition unit (S220 to S240, S520 to S540) configured to transition the electronic control device to a stopped state or a sleep state when, upon receiving power supply switching state information indicating whether each of the plurality of power supply switching units is in the conductive state or the cut-off state from a power supply control device (2, 101 to 107) connected to the electronic control device so as to be able to communicate data with the electronic control device and configured to control the operation of the plurality of power supply switching units, all of the plurality of power supply switching units are in the cut-off state based on the received power supply switching state information, or when all of the plurality of power supply switching units other than the power supply switching unit connected to the electronic control device are in the cut-off state.

8. a first control device (3, 4, 5, 104 to 116) that receives power supply from a power source (7, 51, 52, 117) via a power supply switching unit (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conductive state that conducts a power supply path and a cut-off state that cuts off the power supply path; A second control device (2, 101 to 107) that is connected to the first control device so as to be able to communicate data with the first control device, is configured to be able to transmit and receive communication frames, and is configured to control the operation of the power supply switching unit; The first control device is an end notification unit (S10, S20, S310, S320, S325) configured to transmit an end notification to the second control device when a preset cut-off condition indicating that the power supply switching unit connected to the first control device may be set to the cut-off state is satisfied; a sleep transition unit (S30 to S60, S330 to S360) configured to transition the first control device to a sleep state when the communication frame is not received from any of the one or more communication devices (2 to 5, 101 to 116, 118) connected to the first control device so as to be capable of data communication within a preset reception determination time after the interruption condition is established; A communication system (1, 100) comprising:

9. a plurality of power supply switching units (15, 16, 17, 173, 174, 183, 184, 195, 196, 215, 216, 235, 236, 237, 255, 256) configured to switch between a conductive state in which a power supply path is conductive and a cut-off state in which the power supply path is cut off; a first control device (3, 4, 5, 104 to 116) that receives power from a power source (7) via at least one of the plurality of power supply switching units; A second control device (2, 101 to 107) connected to the first control device so as to be able to perform data communication with the first control device and configured to control the operation of the plurality of power supply switching units; The second control device is a state information transmission unit (S120, S420) configured to transmit power supply switching state information indicating whether each of the plurality of power supply switching units is in the conductive state or the cut-off state to the first control device; The first control device is A communication system (1, 100) including a cut-off transition unit (S220 to S240, S520 to S540) configured to transition the first control device to a stopped state or a sleep state when all of the multiple power supply switching units are in the cut-off state, or when all of the multiple power supply switching units other than the power supply switching unit connected to the first control device are in the cut-off state, based on the power supply switching state information received from the second control device.

10. A communication system (100) according to claim 8 or claim 9, The communication system includes: A slave control device (108 to 116) is included as the first control device, A zone control device (104 to 107) is connected to the slave control device so as to be capable of data communication and has the power supply switching unit (195, 196, 215, 216, 235, 236, 237, 255, 256), The second control device includes a central control device (101) that is connected to the zone control devices so as to be capable of data communication and configured to control the operation of the power supply switching unit, The slave control device and the central control device are connected to each other via the zone control device so as to be able to communicate data with each other in a communication system.

11. A communication system (100) according to claim 8 or claim 9, The communication system includes: A slave control device (108 to 116) is included as the first control device, The second control device includes a zone control device (104 to 107) that is connected to the slave control device so as to be able to communicate data with the slave control device, that is equipped with the power supply switching unit (195, 196, 215, 216, 235, 236, 237, 255, 256), and that is configured to control the operation of the power supply switching unit, and a central control device (101) that is connected to the zone control device so as to be able to communicate data with the zone control device, The slave control device and the central control device are connected to each other via the zone control device so as to be able to communicate data with each other in a communication system.

12. A communication system (100) according to claim 8 or claim 9, The communication system includes: A slave control device (108-116), The zone control device (104 to 107) connected to the slave control device so as to be capable of data communication is included as the first control device, A communication system including, as the second control device, an upstream power distribution unit (102, 103) having the power supply switching unit (173, 174, 183, 184), and a central control device (101) connected to enable data communication between the zone control devices and the upstream power distribution unit.

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