JP7503013B2 - Electronic control device and method for starting electronic control device - Google Patents

Description

The present invention relates to an electronic control device mounted on a vehicle and a method for starting the electronic control device.

Vehicles such as automobiles are equipped with an in-vehicle network that controls the vehicle by coordinating multiple electronic control units (ECUs: Electronic Control Units) that control the in-vehicle devices. In an in-vehicle network in which multiple nodes are connected, the following technology, for example, has been proposed to efficiently control each node. In this technology, the network is formed from multiple network segments that are separated from each other by at least one gateway. A network manager in the gateway then synchronizes the multiple network segments upon request, and controls all of the nodes (joining devices) connected to each network segment to start up (wake up) or go into a sleep state.

JP 2003-333070 A

However, in the conventional technology described above, there was no control to start or hibernate each node individually. For this reason, when this technology is applied to an in-vehicle network to which multiple electronic control devices are connected, situations may arise where electronic control devices that do not need to be started are started, resulting in unnecessary power consumption in some cases. In response to this issue, the Control Area Network (CAN) protocol based on the ISO 11898-6 standard specifies a selective wake-up function for selectively waking up nodes connected to the network. However, ICs that support this selective wake-up function are generally expensive, and there are cases where it becomes necessary to update the software of existing systems.

Therefore, one aspect of the present invention aims to make it possible to selectively start electronic control devices connected to an in-vehicle network while keeping implementation costs down, thereby reducing the power consumption of the entire in-vehicle system.

In one aspect of the present invention, an electronic control device that is mounted on a vehicle, communicably connected to a plurality of electronic control devices, and relays communication data is configured as follows: When a first electronic control device among the plurality of electronic control devices identifies that a predetermined activation condition for a second electronic control device among the plurality of electronic control devices is satisfied, the electronic control device receives a start command from the first electronic control device, the start command including information indicating that the second electronic control device is the target for activation, and transmits the start command to the second electronic control device based on the information, while transmitting a pause command to electronic control devices among the plurality of electronic control devices other than the first electronic control device and the second electronic control device based on the information.

The present invention makes it possible to selectively start electronic control devices connected to an in-vehicle network while keeping implementation costs down, thereby reducing the power consumption of the entire in-vehicle system.

1 is a block diagram showing an example of an in-vehicle system according to an embodiment of the present invention; 2 is a block diagram showing an example of a hardware configuration of a gateway ECU in one embodiment of the present invention. FIG. FIG. 2 is a block diagram showing an example of a hardware configuration of an ECU in one embodiment of the present invention. 4 is a flowchart showing an example of a startup process of an ECU in one embodiment of the present invention. 2 is a block diagram showing an example of a hardware configuration of an ECU that controls a fuel vapor processing device according to an embodiment of the present invention. FIG. 4 is a block diagram showing an example of a startup process of an ECU that controls a fuel vapor processing device according to an embodiment of the present invention. FIG.

Specific examples of embodiments for carrying out the present invention will be described in detail below with reference to the attached drawings. Note that in some of the drawings, only the reference numerals of the components are given, and the names are omitted.

FIG. 1 shows an example of an in-vehicle system 10 that is installed in a vehicle such as an automobile.
The in-vehicle system 10 includes networks 11, 12, 13, and 14, which are connected to each other via a gateway ECU 15 so as to be able to communicate with each other.

In network 11, the nodes of ECU 21 and ECU 22 are connected via bus 31. In network 12, the nodes of ECU 23 and ECU 24 are connected via bus 32. In network 13, the nodes of ECU 25 and ECU 26 are connected via bus 33. In network 14, the node of ECU 27 is connected via bus 34. In this embodiment, each of networks 11 to 14 is configured as a CAN (Controller Area Network). However, these networks may also be configured using any other protocol, such as LIN (Local Interconnect Network) or FlexRay. Furthermore, the number of these networks and the number of nodes included in the networks are not limited to the above configuration.

The gateway ECU 15 has the function of monitoring the communication traffic in the networks 11-14, and relaying the communication data received from each of the networks 11-14 and transmitting it to other networks. For example, if the protocol of the network from which the communication data is sent is different from that of the network to which the data is relayed, the gateway ECU 15 can convert the communication data into a protocol that can be processed in the network to which the data is relayed before transmitting the data. The gateway ECU 15 also has the function of transmitting start commands or pause commands to each of the ECUs 21-27 according to the operating status of the ECUs 21-27 identified by the results of monitoring the communication traffic of the networks 11-14.

ECUs 21 and 22 connected to bus 31 of network 11, ECUs 23 and 24 connected to bus 32 of network 12, ECUs 25 and 26 connected to bus 33 of network 13, and ECU 27 connected to bus 34 of network 14 each have the function of electronically controlling in-vehicle equipment.

Figure 2 shows an example of the hardware configuration of the gateway ECU 15. The gateway ECU 15 includes a microcomputer 150. The microcomputer 150 includes a processor 151, a RAM 152, and a ROM 153. The gateway ECU 15 also includes communication interfaces 154, 155, 156, and 157.

The processor 151 is hardware that executes a set of instructions (such as data transfer, calculation, processing, control, and management) written in a program, and is composed of an arithmetic unit, registers that store instructions and information, peripheral circuits, etc. The processor 151 loads the program stored in the ROM 153 into the RAM 152 and executes it.

RAM 152 is a volatile memory in which data is lost when the power supply is cut off, and provides a temporary storage area for use by processor 151 during operation.

ROM 153 is a non-volatile memory that allows data to be electrically rewritten, and includes, for example, a flash ROM or an EEPROM. ROM 153 stores a control program that runs when gateway ECU 15 relays communication data, and data such as parameters used in processing the program.

Communication interfaces 154, 155, 156, and 157 are composed of, for example, CAN transceivers, and are respectively connected to bus 31 of network 11, bus 32 of network 12, bus 33 of network 13, and bus 34 of network 14.

Figure 3 shows an example of the hardware configuration of the ECU 21. As shown in Figure 3, the ECU 21 includes a microcomputer 210. The microcomputer 210 includes a processor 211, a RAM 212, and a ROM 213. The ECU 21 also includes a communication interface 214 and an input/output interface 215. Furthermore, the ECU 21 includes a startup circuit 216.

The functions of the processor 211, RAM 212, and ROM 213 of the microcomputer 210 are similar to those of the processor 151, RAM 152, and ROM 153 of the gateway ECU 15 described above, respectively, and therefore in principle will not be described. The difference from the case of the gateway ECU 15 is that the ROM 213 of the ECU 21 stores a control program that runs when the ECU 21 controls the controlled device, and data such as parameters used in processing the program.

The communication interface 214, like the communication interfaces 154 to 157 of the gateway ECU 15, is composed of, for example, a CAN transceiver, and is connected to the bus 31 of the network 11.

The input/output interface 215 is composed of an A/D converter, a D/A converter, a D/D converter, etc., and is connected to an external device related to the control of the in-vehicle device to be controlled, and provides input/output functions for analog and digital signals to the external device.

The start-up circuit 216 is an electronic circuit that controls the start-up (wake-up) of the microcomputer 210. The start-up circuit 216 is connected to an external power source (not shown) and also to the communication interface 214 and the input/output interface 215, and starts the power supply to the microcomputer 210 and starts the ECU 25 by input signals from the communication interface 214 and the input/output interface 215. The start-up circuit 216 can also cause the microcomputer 210, whose processor 211 has stopped processing a program, to resume processing when power is already being supplied. Similarly, the start-up circuit 216 can also cause the microcomputer 210 to transition to a pause (sleep) state by input signals from the communication interface 214 and the input/output interface 215. At this time, the start-up circuit 216 can stop the program processing while maintaining the power supply to the microcomputer 210, or can stop the power supply itself.

In other words, in this embodiment, "starting" the ECU can include both the concept of turning the ECU's power supply from an off state to an on state, and the concept of resuming program processing in an ECU where the power supply itself is on but program processing by the processor has stopped. Also, in this embodiment, "pausing" the ECU can include both the concept of turning the ECU's power supply from an on state to an off state, and the concept of stopping program processing by the processor while the power supply itself is on. Note that the aforementioned gateway ECU 15 also has a similar startup circuit, but illustrations and explanations are omitted.

Each of the ECUs 22 to 27 has a hardware configuration similar to that of the ECU 21 shown in FIG. 3. That is, each of the ECUs 22 to 27 has a microcomputer equipped with a processor, RAM, and ROM. Each of the ECUs 22 to 27 also has a communication interface connected to the bus of the network to which it belongs, and an input/output interface that provides input/output functions for external devices related to the control of the in-vehicle device to be controlled. Furthermore, each of the ECUs 22 to 27 has a startup circuit similar to that of the ECU 21.

Next, with reference to the sequence diagram shown in FIG. 4, a process will be described in such an in-vehicle system 10 in which one of the ECUs 21 to 27 functions as a master ECU and the other slave ECUs among the ECUs 21 to 27 are started from the master ECU. In this embodiment, as an example, the ECU 21 is the master ECU (first electronic control unit) and the other ECUs 22 to 27 are slave ECUs. Among the ECUs 22 to 27, the ECU 25 is the ECU to be started (second electronic control unit). In this case, the ECUs 22 to 24 and the ECUs 26 to 27 are non-start-target ECUs.

In step 101 (represented as S101 in the figure, and the same applies below), ECU21, which is the master ECU, receives information indicating that the start-up conditions of ECU25, which is the ECU to be started, have been met. As a result, ECU21 identifies that the start-up conditions of ECU25 have been met.

In step 102, ECU 21 transmits a wake-up frame to gateway ECU 15, the wake-up frame including information indicating that ECU 25 is the target for startup. The wake-up frame is one form of startup command data.

In step 103, the gateway ECU 15 receives the wake-up frame sent from the ECU 21.

In step 104, the gateway ECU 15 analyzes the received wake-up frame, performs protocol conversion as necessary, and identifies the ECU to which the wake-up frame is to be sent. That is, in this embodiment, the gateway ECU 15 identifies that the destination of the wake-up frame is ECU 25 based on information contained in the wake-up frame indicating that ECU 25 is the activation target. The gateway ECU 15 then relays the wake-up frame and transmits it to ECU 25.

In step 105, ECU 25, which is the ECU to be started, receives a wake-up frame from the gateway ECU 15.

In step 106, the ECU 25 starts up based on the received wake-up frame.

In step 107, the gateway ECU 15 transmits a sleep command to the ECUs 22-24 and 26-27 other than the ECU 25 that is the ECU to be started. The gateway ECU 15 can perform the process of step 107 simultaneously with the process of step 104 or subsequent to the process of step 104, without waiting for the ECU 25 to finish the processes of steps 105 and 106. Alternatively, when the ECU 25 is started, a notification may be sent to the gateway ECU 15, and the process of step 107 may be performed on the condition that the gateway ECU 15 receives the notification.

In step 108, ECUs 22-24 and 26-27, which are not to be started, receive a sleep command from the gateway ECU 15.

In step 109, ECUs 22-24 and 26-27 transition to a sleep state based on the received sleep command. If ECUs 22-24 and 26-27 are already in a sleep state, they remain in that state.

As described above, in this embodiment, in the in-vehicle system 10, the ECU 21 functioning as the master ECU does not transmit a wake-up frame to all the slave ECUs, but transmits a wake-up frame to the gateway ECU 15. The gateway ECU 15 also does not transmit a wake-up frame to all the slave ECUs connected to each network, but transmits a wake-up frame to the ECU 25 to be started, based on the information contained in the wake-up frame received from the ECU 21, by using the relay function of the gateway ECU 15. In addition, the gateway ECU 15 transmits a sleep command to the ECUs 22 to 24 and 26 to 27 that are not to be started. This allows only the ECU 25 that needs to be started to be started, and it is possible to avoid a state in which even the ECUs that are not to be started are started. Therefore, it is possible to reduce the power consumption of the in-vehicle system 10 as a whole.

In particular, in recent in-vehicle systems, as electronic control has become more complex, the number of devices to be controlled has become more diverse, and there is a tendency for a large number of ECUs to be installed. In such in-vehicle systems, reducing power consumption is an important issue to prevent power shortages caused by power consumption exceeding the power supplied from the battery. According to this embodiment, as described above, it is possible to selectively start up the necessary ECUs, so power consumption can be effectively reduced.

In addition, according to this embodiment, even in an existing vehicle-mounted system that does not have an ECU that uses an IC that supports the selective wake-up function proposed in recent years, the relay function of the gateway ECU 15 makes it possible to start only the ECU to be started. This makes it possible to reduce power consumption while keeping down implementation costs.

Furthermore, according to this embodiment, the relay function of the gateway ECU 15 transmits the wake-up frame only to the ECU 25 that is the ECU to be started, which is expected to reduce communication traffic compared to the case where the master ECU transmits a wake-up frame to all slave ECUs. As a result, it is possible to suppress collisions of communication data, which in turn makes it possible to suppress the occurrence of communication delays.

Even if ECUs 22-24, 26-27 are put into a sleep state by a sleep command, they can be started up if their operation is necessary. For example, ECUs 22-24, 26-27 can be started up again by sending a start command from the master ECU, just as ECU 25 was started up. Also, in the case of CAN communication, for example, ECUs can be started up again if the signal level of the bus to which ECUs 22-24, 26-27 are connected becomes dominant, as in the conventional case. Furthermore, it is also possible to start up the ECUs again when start conditions corresponding to the controlled devices are satisfied by information received directly from the input/output interfaces of ECUs 22-24, 26-27 (for example, signals from various sensors).

In this embodiment, since it is possible to selectively start the target ECU even when a start command is sent from the master ECU, the start condition based on information that the target ECU would have received directly from an external device in the past may also be started by sending a start command from the master ECU. Below, such a configuration will be explained using an example in which ECU 25, the target ECU, is an ECU (EVAP CU) that controls a fuel vapor processing device mounted on a vehicle.

Examples of activation conditions for the ECU 25 that controls the fuel vapor processing device include activation conditions based on the switching of the ignition switch, the soak time of the vehicle measured by the soak timer, and the switching of the refueling switch. For example, the ECU 25 that controls the fuel vapor processing device can be configured to be activated when any of the following conditions is satisfied: the ignition switch of the vehicle is turned on, the soak time of the vehicle measured by the soak timer is equal to or longer than a predetermined time, and the fuel tank is refueled. In this case, in the past, wiring was provided in the ECU 25 to receive signals for identifying these activation conditions, and the activation conditions were identified as being satisfied by directly receiving signals through each wiring. For this reason, the wiring configuration in the ECU 25 was complicated, and the determination of the activation cause was complicated. In this regard, in this embodiment, since similar information is used in the ECUs that control other in-vehicle devices as for the switching of the ignition switch and the soak time of the vehicle measured by the soak timer, the information is received in the ECU 21, which is the master ECU. The ECU 21 may receive this information directly from wiring connected to the ignition switch or soak timer, or may receive it from other devices via a network.

Figure 5 shows the hardware configuration of the ECU 25 that controls the fuel vapor processing device. Similar to the configuration of the ECU 21, the ECU 25 includes a microcomputer 250, a communication interface 254, an input/output interface 255, and a startup circuit 257. Note that the processor 251, RAM 252, and ROM 253 are not shown. The ECU 25 also includes a refueling switch 256.

The refueling switch 256 is a switch that identifies, based on a signal from the sensor 300, that refueling has been performed on the fuel tank that stores the fuel to be supplied to the vehicle's internal combustion engine. The refueling switch 256 also receives a signal from the sensor 300 via the input/output interface 255, but this part is not shown in FIG. 5.

Note that other signals that the ECU 25 receives from external devices via the input/output interface 255 may include signals from a pressure sensor, a fuel vapor temperature sensor, etc. Furthermore, signals that the ECU 25 outputs may include signals that control a purge valve that controls the output of fuel vapor to a fuel vapor purge mechanism, etc.

The start-up circuit 257 is connected to the communication interface 254, and is capable of receiving a signal via the communication interface 254 based on the reception of a start-up command from the outside. The start-up circuit 257 is also connected to the refueling switch 256, and is capable of receiving a signal indicating that the refueling switch 256 has been turned on.

In addition, in this specific example, the communication interface 254 of the ECU 25 is a CAN transceiver, and the network 33 to which the ECU 25 is connected is assumed to perform CAN communication.

FIG. 6 is a flowchart showing the process performed when the ECU 25 is started up.
In step 201, the start circuit 257 of the ECU 25 determines whether or not the start conditions via CAN communication are satisfied. Here, the start conditions via CAN communication being satisfied means that a wake-up frame transmitted from the ECU 21, which is the master ECU, and relayed by the gateway ECU 15 is received via the communication interface 254. If the start conditions via CAN communication are satisfied (Yes), the process proceeds to step 203. On the other hand, if the start conditions via CAN communication are not satisfied (No), the process proceeds to step 202.

In step 201, when the ECU 21 receives information indicating that the startup conditions of the ECU 25 are satisfied, as described in steps 101 and 102 of FIG. 4, the ECU 21 transmits a wake-up frame including information indicating that the ECU 25 is to be started. That is, in this specific example, the ECU 21 transmits a wake-up frame when it receives information indicating at least one of the following: that the ignition switch has been turned on; and that the soak time measured by the soak timer has reached or exceeded a predetermined time.

In step 202, the start circuit 257 determines whether the start condition is met by turning on the refueling switch 256. If the start condition is met (Yes), the process proceeds to step 203, whereas if the start condition is not met (No), the process returns to step 201 and waits.

In step 203, the start-up circuit 257 starts supplying power and starts the ECU 25. As described above, the start-up circuit 257 can also transmit a command to start the processor 251, whose program processing has been stopped, when power is already being supplied. When power is already being supplied in this way, the wake-up frame received by CAN communication and the signal from the refueling switch 256 may be received by the processor 251 via the bus, and the processor 251 may start up by processing the program.

In this way, part of the information that constitutes the start-up conditions for ECU 25, which controls the fuel vapor processing device, is received by ECU 21, which is the master ECU, and ECU 25 starts up by receiving a wake-up frame when these start-up conditions are satisfied. This allows the start-up condition information that ECU 25 would have received from separate wiring in the past to be combined through CAN communication. This simplifies the wiring configuration in ECU 25 and makes it easier to determine the cause of start-up. Meanwhile, ECU 21, which is the master ECU, can also transmit similar information to other slave ECUs that use the information that constitutes the start-up conditions.

In this specific example, an ECU that controls a fuel vapor processing device has been used as an example, but in the case of ECUs that control other controlled devices, it is also possible to receive all or part of the information that constitutes the activation conditions on the master ECU side and activate the ECU by transmitting a wake-up frame from the master ECU.

The above-described embodiments of the present invention are merely some of the possible implementations within the technical scope of the present invention, and are disclosed as examples of the present invention, and do not limit the technical scope of the present invention. Furthermore, the functional and physical configurations in each embodiment are not limited to the above-described aspects, and for example, each function or physical resource can be integrated and implemented, or conversely, can be further distributed and implemented, and further configurations can be added, deleted, or replaced with other configurations for part of the configuration.

10...In-vehicle system, 11-14...Network, 15...Gateway ECU, 21-27...ECU, 31-34...Bus

Claims (6)

An electronic control device mounted on a vehicle, communicably connected to a plurality of electronic control devices, and relaying communication data,
receiving, from a first electronic control device among the plurality of electronic control devices, a start-up command including information indicating that the second electronic control device is to be started when the first electronic control device among the plurality of electronic control devices identifies that a predetermined start-up condition for the second electronic control device among the plurality of electronic control devices is satisfied, and transmitting the start-up command to the second electronic control device based on the information;
a stop command is transmitted to an electronic control device other than the first electronic control device and the second electronic control device among the plurality of electronic control devices based on the information;
Electronic control unit. the second electronic control device is an electronic control device that controls a fuel vapor processing device mounted on the vehicle,
The predetermined activation condition is at least one of a condition based on switching of an ignition switch and a condition based on a soak time of the vehicle measured by a soak timer.
2. The electronic control device according to claim 1. An electronic control device mounted on a vehicle and communicatively connected to a plurality of other electronic control devices via an electronic control device that relays communication data,
a start-up command including information indicating that the electronic control device to be started is a start-up target is transmitted to an electronic control device that relays the communication data when the start-up command receives information indicating that a predetermined start-up condition for the electronic control device to be started among the plurality of electronic control devices and identifies that the start-up condition is satisfied ;
the electronic control device to be activated is an electronic control device that controls a fuel vapor processing device mounted on the vehicle,
The predetermined activation condition is at least one of a condition based on switching of an ignition switch and a condition based on a soak time of the vehicle measured by a soak timer.
Electronic control unit. A method for starting an electronic control device that is mounted on a vehicle and is communicatively connected to a plurality of other electronic control devices via an electronic control device that relays communication data, comprising the steps of:
When a first electronic control unit of the plurality of electronic control units identifies that a predetermined startup condition for a second electronic control unit of the plurality of electronic control units is satisfied, the first electronic control unit transmits a startup command including information indicating that the second electronic control unit is a startup target to an electronic control unit that relays the communication data;
an electronic control device that relays the communication data receives the start-up command, and transmits the start-up command to the second electronic control device based on the information included in the start-up command, while transmitting a pause command to electronic control devices other than the first electronic control device and the second electronic control device among the plurality of electronic control devices;
The second electronic control unit receives the start-up command and starts up based on the start-up command, while an electronic control unit other than the first electronic control unit and the second electronic control unit receives the pause command and transitions to a pause state based on the pause command.
How to start an electronic control unit. the second electronic control device is an electronic control device that controls a fuel vapor processing device mounted on the vehicle,
The predetermined activation condition is at least one of a condition based on switching of an ignition switch and a condition based on a soak time of the vehicle measured by a soak timer.
5. A method for starting an electronic control unit according to claim 4. An electronic control device that controls a fuel vapor processing device and is mounted on a vehicle and communicably connected to other electronic control devices via an electronic control device that relays communication data,
When the other electronic control unit identifies that at least one of the start conditions based on the switching of an ignition switch and the soak time of the vehicle measured by a soak timer is satisfied, the start command is transmitted from the other electronic control unit, and when the start command is received from the electronic control unit that performs relay processing of the communication data, the start command is started based on the start command.
Electronic control unit.