JP2020088568A - Electronic control device - Google Patents

Abstract

To provide a technique for enhancing reliability for controlling Ethernet communication in a network system in which on-vehicle electronic control devices communicate with each other in both of CAN and Ethernet.SOLUTION: An electronic control device of the present disclosure is any one of a plurality of electronic control devices constituting an on-vehicle network system and capable of communicating with each other and includes a first communication control section and a second communication control section. In S400 to S414, the first communication control section controls communication based on CAN with another electronic control device. In S410 and S412, the second communication control section controls communication based on Ethernet with another electronic control device, and when a communication state of CAN is an awake state, enables a communication state based on Ethernet with the other electronic control device, and when a communication state of CAN is in a sleep state, disables a communication state based on Ethernet with the other electronic control device.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to a vehicle-mounted electronic control device.

Some vehicle-mounted network systems use a CAN and an Ethernet together, as disclosed in Japanese Patent Laid-Open No. 2004-242242. CAN is an abbreviation for Controller Area Network. CAN and Ethernet are registered trademarks.
In the technique described in Patent Document 1, electronic control devices respectively connected to CAN and Ethernet communicate with each other via a relay device.

JP, 2008-098733, A

The inventor of the present application is considering a network system in which electronic control devices communicate with each other by both CAN and Ethernet without a relay device.
Since network management technology for controlling CAN communication in a vehicle is established, for example, when an awake factor occurs in the electronic control unit when the ignition switch is off, the CAN network management prevents communication of the CAN communication state. The reliability of transition from the sleep state to the awake state in which communication is possible is high. Hereinafter, network management is also abbreviated as NM.

However, the network management technology for in-vehicle Ethernet communication is not yet fully established. Therefore, as a result of a detailed study by the inventor, for example, when an awake factor occurs in the electronic control unit when the ignition switch is in the off state, the Ethernet network management changes the communication state of the Ethernet from communication disabled to communication enabled. The problem of low reliability was found.

In one aspect of the present disclosure, it is desirable to provide a technique for enhancing reliability of controlling Ethernet communication in a network system in which vehicle-mounted electronic control devices communicate with each other via both CAN and Ethernet.

An electronic control device according to an aspect of the present disclosure is an electronic control device that constitutes an in-vehicle network system (2) and is any one of a plurality of electronic control devices (10) that can communicate with each other. The communication control unit (12, S400 to S414) and the second communication control unit (14, S410, S412, S420 to S424).

The first communication control unit controls CAN communication with another electronic control device. The second communication control unit controls Ethernet communication with another electronic control device, and if the CAN communication state controlled by the first communication control unit is the awake state, the second communication control unit performs Ethernet communication with the other electronic control device. When the communication state of the CAN controlled by the first communication control unit is the sleep state, the communication state by Ethernet with another electronic control device is disabled.

According to such a configuration, the communication state of Ethernet is controlled based on the CAN network management of which reliability is established, so that Ethernet communication can be controlled with high reliability.

The block diagram which shows the network system by this embodiment. The figure which shows the communication state of CAN. The flowchart which shows a communication process. The time chart which shows the transition of the communication state of Ethernet. Another time chart showing the transition of the Ethernet communication state. The flowchart which shows the communication request process of Ethernet.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
[1. Constitution]
The network system 2 shown in FIG. 1 is installed in a vehicle and includes a main network 20 and sub-networks 50 to 56.

The main network 20 is a network including four electronic control units 10, CAN buses 30 to 38, and Ethernet buses 40 to 48. Hereinafter, the electronic control unit will be abbreviated as ECU.

The CAN buses 30 to 38 are signal lines for transmitting CAN frames according to the CAN protocol. The CAN bus 30 is a main signal line. The CAN buses 32 to 38 are sub-signal lines that connect the CAN bus 30 and each of the four ECUs 10.

The Ethernet buses 40 to 48 are signal lines for transmitting Ethernet frames according to the Ethernet protocol. The Ethernet buses 40 to 48 are signal lines that connect the four ECUs 10 to each other in a one-to-one relationship.

The ECU 10 is mainly composed of a microcomputer including a CPU, a semiconductor memory such as a RAM, a ROM and a flash memory, and an input/output interface. Hereinafter, the semiconductor memory is also simply referred to as a memory. The ECU 10 may be equipped with one microcomputer or a plurality of microcomputers.

Various functions of the ECU 10 are realized by the CPU executing programs stored in the non-transitional substantive recording medium. In this example, the memory corresponds to a non-transitional tangible recording medium that stores the program. When the CPU executes this program, a method corresponding to the program is executed.

The ECU 10 includes a CAN communication control unit 12 and an Ethernet communication control unit 14 as a functional configuration realized by the CPU executing a program.
The method of realizing these elements configuring the ECU 10 is not limited to software, and one or more hardware may be realized for one or all of the elements. For example, when the above function is realized by an electronic circuit which is hardware, the electronic circuit may be realized by a digital circuit including a large number of logic circuits, an analog circuit, or a combination thereof.

The CAN communication control unit 12 controls CAN communication according to the CAN protocol. That is, the CAN communication control unit 12 transmits and receives CAN frames via the CAN buses 30 to 38.

FIG. 2 shows the CAN communication state set by the CAN network management. The CAN communication state set by the CAN network management is also called an NM state.

In the present embodiment, for example, five NM states of BusSleep, RepeatMessageState, NormalOperationState, ReadySleepState, and PrepareBusSleepMode defined in AUTOSAR are set in the CAN. AUTOSAR is an abbreviation for Automotive Open System Architecture.
Since the details of the above five NM states and the details of the transition of the NM states are defined in AUTOSAR, the description thereof will be omitted.

In Repeat Message State, since it is uncertain whether CAN communication is possible or impossible depending on the network system, it is described as impossible/possible. However, in the present embodiment, CAN communication is enabled when the NM state of the CAN is RepeatMessageState.
The CAN communication control unit 12 causes the above five NM states to transition based on the driving state of the vehicle and the like by the CAN NM process.

The Ethernet communication control unit 14 controls Ethernet communication according to the Ethernet protocol. That is, the Ethernet communication control unit 14 transmits and receives Ethernet frames via the Ethernet buses 40 to 48.

Then, the Ethernet communication control unit 14 sets the Ethernet communication state based on the NM state of CAN.
In the NM state of the CAN shown in FIG. 2, it is not determined whether at least one of CAN transmission and reception is possible in BusSleep, RepeatMessageState, and PrepareBusSleepMode, or whether CAN communication is possible or not by the network system. In the case of these three NM states, the Ethernet communication control unit 14 sets the communication state of Ethernet to communication disabled.

When the CAN NM states are BusSleep, RepeatMessageState, and PrepareBusSleepMode, it is also said that the CAN communication state is a sleep state in which CAN communication is not possible.

On the other hand, when the CAN NM state is ReadySleepState and NormalOperationState, the Ethernet communication control unit 14 sets the Ethernet communication state to be communicable.

When the NM state of CAN is ReadySleepState and NormalOperationState, it is also said that the CAN communication state is an awake state in which CAN communication is possible.

Each of the sub-networks 50 to 56 is configured by connecting a plurality of ECUs to the CAN buses 60 to 66, respectively. The CAN buses 60 to 66 are signal lines for communicating CAN frames according to the CAN protocol. The ECUs mounted on the vehicle are classified according to their functions and form a sub-network. Note that, instead of the CAN buses 60 to 66, a signal line for transmitting a frame according to a protocol other than the CAN protocol may be used.

[2. Communication processing]
The communication process executed by the electronic control unit 10 will be described with reference to FIGS. The flowcharts of FIGS. 3 and 6 are always executed at a predetermined time interval regardless of whether the ignition switch is on or off.

Further, in FIGS. 4 and 5, for simplification of description, only three ECUs A, B, and C out of the four ECUs shown in FIG. 1 are shown.
[2-1. Communication processing based on NM state of CAN]
In S400 of FIG. 3, the CAN communication control unit 12 sets an appropriate NM state among the above five NM states based on the driving state of the vehicle by the CAN NM process.

In step S402, the CAN communication control unit 12 acquires the NM state of the CAN of this cycle for executing the flowchart of FIG. In step S404, the CAN communication control unit 12 compares the NM state of this cycle with the NM state of the previous cycle.

In S406, the CAN communication control unit 12 determines whether or not the NM state of this cycle has changed from the NM state of the previous cycle. If the determination in S406 is No, that is, if the NM state in the current cycle has not changed from the NM state in the previous cycle, this processing ends. Since the NM state has not changed, the Ethernet communication state also does not change.

If the determination in S406 is Yes, that is, if the NM state of the current cycle has changed from the NM state of the previous cycle, the CAN communication control unit 12 determines in S408 that the NM state of the current cycle is BusSleep, RepeatMessageState, or PrepareBusSleepMode. It is determined whether or not.

If the determination in S408 is No, that is, if the NM state of the current cycle is neither BusSleep, RepeatMessageStage, or PrepareBusSleepMode, and NormalOperatingState or ReadySleepState, the CAN communication control unit 12 that determines in S410 is that the CAN communication control unit 12 is CAN communication. ..

In this case, the CAN communication control unit 12 determines that Ethernet communication is also possible, and notifies the Ethernet communication control unit 14 to make the communication state of Ethernet available. The Ethernet communication control unit 14 enables the communication state of Ethernet based on the notification from the CAN communication control unit 12.

If the determination in S408 is Yes, that is, if the NM state of this cycle is either BusSleep, RepeatMessageStatement, or PrepareBusSleepMode, the CAN communication control unit 12 cannot transmit CAN communication at least based on the NM state in FIG. It is determined that whether or not transmission/reception is possible is uncertain.

In this case, in S412, the CAN communication control unit 12 determines at least whether CAN communication cannot be transmitted or can be transmitted/received. Therefore, the Ethernet communication control unit 14 sets the communication state of Ethernet to communication disabled. To notify. The Ethernet communication control unit 14 disables the communication state of Ethernet based on the notification from the CAN communication control unit 12.

In step S414, the CAN communication control unit 12 sets the NM state of this cycle as the NM state of the previous cycle, and ends this processing.
Next, a description will be given of the Ethernet communication state that changes with the transition of the CAN NM state.

(1) Ethernet communication state transitions from communication disabled to communication enabled As shown in FIG. 4, when the NM state of ECU A among ECU A, ECU B, and ECU C is BusSleep, an awake factor occurs in ECU A. Then, after a lapse of the preparation time for awakening, the ECU A sets the NM state of CAN to RepeatMessageState. As described above, in this embodiment, the CAN is communicable when the NM state of the CAN is RepeatMessageState.

The following factors can be considered as awake factors.
-The vehicle power is switched from ignition off to accessories and ignition on.
・Awake request is generated from the application program installed in each ECU. For example, it becomes the time to start the pre-air conditioning of the vehicle before the preset time such as the scheduled boarding time of the driver.

・Vehicle doors are opened and closed.
-Receive an NM frame indicating that an awake factor has occurred from another ECU.
An Ethernet communication request is issued from the Ethernet communication control unit 14.

When the ECU A changes the NM state from BusSleep to RepeatMessageState, the NM state of the current cycle changes from the NM state of the previous cycle, and the determination at S406 is Yes, but the NM state is RepeatMessageState, so the Ethernet communication state Ethernet communication is not possible and communication is still impossible.

When the ECU A causes an awake factor in its own ECU and transitions the NM state from BusSleep to RepeatMessageState, the ECU A transmits an NM frame indicating that the awake factor has occurred in its own ECU to the CAN bus as a CAN frame. Hereinafter, the NM frame indicating that the awake factor has occurred is also simply referred to as an awake NM frame.

Upon receiving the awake NM frame from the ECU A, the ECUs other than the ECU A set the NM state of the own ECU to RepeatMessageState after a lapse of the preparation time for the awake. Then, the NM frame indicating that the awake factor has occurred in its own ECU is transmitted to the CAN bus as a CAN frame.

In the ECUs other than the ECU A as well, the NM state of this cycle changes from the NM state of the previous cycle, and the determination in S406 is Yes, but the NM state is RepeatMessageState, so the communication state of Ethernet is incommunicable. There is.

The ECU whose NM state has changed from BusSleep to RepeatMessageStateSends an awake NM frame to the CAN bus until the awake cause is removed from the ECU.

When the NM state of the CAN becomes the RepeatMessageState, the ECU A, the ECU B, and the ECU C count the transition time for transition to the NormalOperationState, which is the NM state for performing normal CAN communication, with a timer.

Since the ECU A has an awake factor in its own ECU, when the count value of the timer reaches a predetermined value, the ECU A determines that the transition time for making a transition to NormalOperationState has elapsed, and sets the NM state of its own ECU to NormalOperationState. Set.

Since the ECUs other than the ECU A receive the awake NM frame from the ECU A, the ECU itself needs to also awake. When the count value of the timer reaches a predetermined value, the transition time for transition to the NormalOperationState has passed. Then, as in the ECU B of FIG. 4, the NM state is set to NormalOperationState.

On the other hand, an ECU other than the ECU A receives the awake NM frame from the ECU A, but if the awake factor does not occur in the own ECU, even if the count value of the timer reaches a predetermined value, Like the ECU C of 1., the NM state of its own ECU is set to ReadySleepState instead of NormalOperationState.

The Ethernet communication control unit 14 of the ECU that has changed the NM state of the CAN from RepeatMessageState to NormalOperationState or ReadySleepState makes the Ethernet communication state communicable.

(2) Ethernet communication state transitions from communicable state to non-communicable state As shown in FIG. 5, when the NM state of ECU A among ECU A, ECU B, and ECU C is Normal Operation State, ECU A has no cause for awakening. Then, the CAN communication control unit 12 of the ECU A sets the NM state from NormalOperationState to ReadySleepState. Even if the NM state transits from NormalOperationState to ReadySleepState, the Ethernet communication state remains communicable.

The CAN communication control unit 12 stops the transmission of the awake NM frame when the awake cause disappears in the ECU.
The CAN communication control unit 12 clears the timer that counts the transition time for transition from ReadySleepState to PrepareBusSleepMode when the self ECU transmits an awake NM frame or receives an awake NM frame from another ECU, and the timer count is initialized. Resume from value.

Even if the CAN communication control unit 12 of the ECU A stops transmitting the awake NM frame, the ECU B clears the timer while the ECU B transmits the awake NM frame, and restarts the count of the timer from the initial value.

The CAN communication control unit 12 of the ECU C clears the timer while receiving the awake NM frame from the ECU A or the ECU B even if the ECU does not send the awake NM frame in ReadySleepState, and the timer Restarts counting from the initial value.

In FIG. 5, when all the ECUs stop transmitting the awake NM frame, when the ECU B finally transmits the awake NM frame, all the ECUs clear the timer and restart the timer counting from the initial value.

Then, when the count value of the timer reaches a predetermined value and the transition time for transition from ReadySleepState to PrepareBusSleepMode elapses, the CAN communication control unit 12 of each ECU sets the NM state of CAN to PrepareBusSleepMode.

Then, the CAN communication control unit 12 starts the counting of the timer that counts the transition time for transition from the PrepareBusSleepMode to the BusSleep from the initial value.

When the NM state of the ECU transits to the PrepareBusSleepMode, the CAN communication control unit 12 notifies the Ethernet communication control unit 14 to set the Ethernet communication state from communicable to communicable.

When the count value of the timer that counts the transition time for the NM state of CAN to transit to BusSleep reaches a predetermined value and the transition time to transition to BusSleep elapses, the CAN communication control unit 12 sets the NM state of its own ECU to BusSleep. To do.

[2-2. Ethernet communication request processing]
In S420 of FIG. 6, the Ethernet communication control unit 14 determines whether or not the own ECU has a communication request for starting or continuing Ethernet communication.

If the determination in S420 is No, that is, if there is no Ethernet communication request, in S422 the Ethernet communication control unit 14 notifies the CAN communication control unit 12 that there is no awake request for CAN. In this case, the CAN communication control unit 12 controls the CAN communication state by CAN network management.

When the determination in S420 is Yes, that is, when there is a communication request to the Ethernet, the Ethernet communication control unit 14 notifies the CAN communication control unit 12 that there is an awake request to the CAN in S424.

In this case, the CAN communication control unit 12 transmits the awake NM frame in response to the awake request from the Ethernet communication control unit 14 even if the awake factor is not generated in the own ECU.

Therefore, when the NM state of the own ECU is either BusSleep, RepeatMessageStage, or PrepareBusSleepMode, and when the Ethernet communication control unit 14 notifies the Ethernet communication control unit 14 of the awake request when the Ethernet communication state is incommunicable, the CAN communication control unit 12 , Determines that an awake factor has occurred in its own ECU, and transmits an awake NM frame.

Thereby, the NM state of CAN transits from BusSleep to NormalOperationState, as shown in FIG. 4, for example. As a result, the communication state of Ethernet changes from communication disabled to communication enabled.

[3. effect]
According to this embodiment described above, the following effects can be obtained.
(1) Based on the CAN network management, the communication status of the Ethernet is enabled when the CAN communication status is the awake status where the CAN communication is possible, and the Ethernet communication cannot be communicated when the CAN communication is in the sleep status. To

As a result, regardless of whether the ignition switch is off or on, if power is supplied to the ECU, Ethernet communication can be controlled with high reliability based on highly reliable CAN network management.

(2) When there is a communication request to the Ethernet, the Ethernet communication control unit 14 notifies the CAN communication control unit 12 of the awake request, and transitions to the awake state even if the CAN communication state is the sleep state. As a result, regardless of whether the ignition switch is off or on, it is possible to set the Ethernet to the communicable communication state after the CAN communication state becomes the communicable awake state.

In the above embodiment, the CAN communication control unit 12 corresponds to the first communication control unit, and the Ethernet communication control unit 14 corresponds to the second communication control unit.
Further, S400 to S414 correspond to the processing of the first communication control unit, and S410, S412, S420 to S424 correspond to the processing of the second communication control unit.

[4. Other Embodiments]
Although the embodiments for implementing the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications can be implemented.

(1) In the above embodiment, if the CAN NM states are RepeatMessageState and PrepareBusSleepMode, the NM state is a transitional NM state that transitions to the next NM state after the transition time elapses, so the NM state is classified as a sleep state. There is. As a result, when the CAN NM state is in a transitional state, the communication state of the Ethernet can be disabled without enabling communication.

(2) The CAN communication control unit 12 of the above embodiment may perform CAN communication according to either the CAN protocol or the CAN-FD protocol.
(3) A plurality of functions of one constituent element in the above embodiment may be realized by a plurality of constituent elements, or one function of one constituent element may be realized by a plurality of constituent elements. .. Further, a plurality of functions of a plurality of constituent elements may be realized by one constituent element, or one function realized by a plurality of constituent elements may be realized by one constituent element. Further, a part of the configuration of the above embodiment may be omitted. Further, at least a part of the configuration of the above-described embodiment may be added to or replaced with the configuration of the other above-described embodiment. Note that all aspects included in the technical idea specified only by the wording recited in the claims are embodiments of the present disclosure.

(4) In addition to the electronic control device 10 described above, a system having the electronic control device 10 as a component, a communication control program for causing a computer to function as the electronic control device 10, and a recording medium recording the communication control program, The present disclosure can be implemented in various forms such as a communication control method.

2: Network system, 10: ECU (electronic control unit), 12: CAN communication control unit, 14: Ethernet communication control unit

Claims (3)

Any one of a plurality of electronic control devices (10) composing an in-vehicle network system (2) and capable of communicating with each other,
A first communication control unit (12, S400 to S414) configured to control CAN (registered trademark) communication with another electronic control device;
If the communication state of the CAN that controls the communication with the other electronic control device via Ethernet (registered trademark) and the first communication control unit controls is the awake state, the communication with the other electronic control device is performed. When the communication state by Ethernet is communicable, and the communication state of the CAN controlled by the first communication control unit is sleep state, the communication state by Ethernet with the other electronic control unit is disabled. A second communication control unit (14, S410, S412, S420 to S424) configured in
An electronic control device including. The electronic control device according to claim 1, wherein
In the case where the second communication control unit is in a normal operation state (NormalOperationState) or a ready sleep state (ReadySleepState) indicating that the communication state of the CAN controlled by the first communication control unit is the awake state, It is configured to enable communication of the communication state by the Ethernet with another electronic control device,
Electronic control unit. The electronic control unit according to claim 1 or 2, wherein
When the second communication control unit (S412, S420 to S424) wants to start or continue the Ethernet communication, the second communication control unit notifies the first communication control unit to set the communication state of the CAN to the awake state. Is composed of,
Electronic control unit.

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