JP2015199444A - Electronic control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic control device which suppresses the power consumption of a battery, and can specify an abnormality occurrence part on a network in a sleep operation.SOLUTION: An electronic control device comprises a communication control part and a transceiver which are connected to each other via a transmission line and a reception line, and a storage part which stores a reception signal received by the transceiver as wakeup data when the electronic control device operates at a sleep mode being an operation mode which is smaller in power consumption than a normal mode being a normal operation state. The transceiver sends out a transmission signal which is inputted from the communication control part via the transmission line to a communication path, and outputs a reception signal received from the communication path to the communication control part via the reception line. The communication control part starts to be transited to the normal mode from the sleep mode when receiving the wakeup data from the transceiver, acquires the wakeup data from the storage part after transited to the normal mode, and determines whether or not the wakeup data are proper.

Description

  The present invention relates to an electronic control device, and more particularly to an electronic control device connected to a communication network including a control unit.

  In recent years, the number of electrical components mounted on a vehicle has increased rapidly as the functions and performance of the vehicle have increased, and the wiring in the vehicle has become more complex and larger. Therefore, in order to suppress the increase in the number of wires in the vehicle, electronic control units (also referred to as ECUs) that control electrical components are grouped by dividing them into body systems for seats and doors, and power train systems such as engines and throttles. In addition, an ECU is connected to each group via a communication bus, a relay connection unit (also referred to as a gateway device) is provided between the communication buses, and a vehicle communication system that performs communication between groups via the relay connection unit is used. ing.

  In a vehicle communication system, if any of a plurality of ECUs existing on a communication bus fails and a communication abnormality occurs, control of the vehicle and electrical components is hindered. Therefore, it is preferable to identify the ECU causing the communication abnormality and the communication bus to which the ECU is connected at an early stage, and to quickly start dealing with the communication abnormality.

  Therefore, the voltage of each filter circuit unit when the CAN communication circuit in a normal state is energized is measured in advance, and the normal value is compared with the voltage value of each filter circuit unit measured at the time of inspection. Based on the filter circuit section to be measured, an abnormality detection system has been devised that can detect an abnormality such as a power fault, a ground fault, and a short circuit, and can identify the communication bus or ECU in which the abnormality has occurred (see Patent Document 1).

  The number of message frames received from the electronic control unit via the communication bus is counted for each ID (identifier) attached to each message frame, and the count number is compared with a preset reference value per unit time. An in-vehicle multiplex communication device that determines whether a message frame is abnormal in communication has been devised (see Patent Document 2).

  Further, when the master node (ECU) transmits the pattern signal and the identification address of the other node in pairs to the communication bus, and the other node receives the pattern signal that is paired with its own identification address, A communication bus monitoring device has been devised in which the reception pattern signal and the reception address are returned to the return communication bus, and the master node monitors the communication bus according to the reception state of the pattern signal and the identification address (see Patent Document 3). ).

JP 2009-130774 A JP 2008-236408 A Japanese Patent Laid-Open No. 06-326716

  In the prior art, a specific signal (for example, a wake-up request signal) is sent to the communication bus, so that the ECU changes from a sleep mode in which communication is stopped to reduce power consumption to a normal mode in which communication can be performed. It is configured to make a transition (wake up). For example, when the gateway device receives a wake-up request signal from another ECU, the wake-up request signal is transmitted to the related ECU after it wakes up.

  The MPU of the gateway apparatus wakes up at the edge (falling edge, etc.) and level (“L” section) of the wakeup request signal, and does not determine the contents of the wakeup request signal. For this reason, it may be possible to wake up even a signal sent on the communication bus due to external noise similar to the wake-up request signal or abnormal operation of another ECU.

  In the configurations of Patent Documents 1 to 3, it is necessary to wake up all the ECUs when determining whether or not the wake-up request signal is appropriate or when performing abnormality determination of the ECU or the communication bus. For this reason, particularly when the vehicle is parked, that is, when the battery is not charged, the dark current increases and the battery is consumed.

  Against the background of the above problems, an object of the present invention is to provide an electronic control device that can reduce the power consumption of a battery and identify an abnormality occurrence location on a network during a sleep operation.

  An electronic control device for solving the above problems is an electronic control device that communicates with another control unit via a communication bus, a communication control unit and a transceiver connected to each other via a transmission line and a reception line, A storage unit that stores a received signal received by the transceiver as wake-up data when the electronic control unit operates in a sleep mode, which is an operation state in which power consumption is lower than that in a normal mode, which is a normal operation state; The transmission signal input from the communication control unit via the transmission line is sent to the communication bus, and the reception signal received from the communication bus is output to the communication control unit via the reception line. When the wakeup data is received from the device, the transition from the sleep mode to the normal mode is started, and after the transition to the normal mode, the storage unit Get the Luo wake-up data, it determines whether the wake-up data is correct ones.

  With the above configuration, by providing a temporary storage unit (buffer) for each communication bus in one electronic control device, it is possible to store a reception signal that seems to be wakeup data, and the wakeup data is processed by the processing of the electronic control device after wakeup. It can be determined whether or not is appropriate. For this reason, it is not necessary to provide a temporary storage part in each control unit. Furthermore, since the determination process is collectively performed by the electronic control device, it is not necessary to wake up the control unit or cause each control unit to perform the determination process, so that current consumption can be reduced.

Schematic of the electronic control device of the present invention. The flowchart explaining the flow of wakeup operation | movement. The timing chart which shows the state of the data and signal in FIG. Schematic of another example of the electronic control device of the present invention.

  Hereinafter, the electronic control device of the present invention is applied to a vehicle gateway device (hereinafter abbreviated as “gateway device”) in which a plurality of networks in which control units are connected by communication lines are formed and the plurality of networks are connected. An example will be described. As shown in FIG. 1, a plurality of in-vehicle communication networks (hereinafter abbreviated as “networks”) 50, 60, 70 are connected to the gateway device 10.

  The configuration of FIG. 1 is “an electronic control device is a vehicle gateway device in which a plurality of networks in which control units are connected by a communication bus are formed and data is relayed between the plurality of networks”. With this configuration, the above-described effects can be achieved.

  The network (generic name of 50, 60, 70, the same applies hereinafter) uses CAN (Controller Area Network) as a communication protocol. Of course, a communication protocol other than CAN may be used, or a different communication protocol may be used for each network. Moreover, the network is divided and configured for each function of the vehicle, for example. It is sufficient that at least one network is connected to the gateway device 10.

  In the network 50, ECUs 1 to 3 are connected to the communication bus 51. Examples of these ECUs include a VSC (Vehicle Stability Control) ECU for stabilizing the turning behavior of the vehicle, an air conditioner ECU for controlling air conditioning in the vehicle, and a travel control system ECU such as an engine ECU for engine control.

  In the network 60, ECUs 4 to 6 are connected to the communication bus 61. These ECUs include a seat ECU for adjusting the position or height of the seat, a power window ECU for controlling opening and closing of the window, an electric mirror ECU for storing and unfolding the electric mirror, and the unlocking of the door lock device. / A vehicle body ECU such as a door lock ECU for locking.

  In the network 70, ECUs 7 to 9 are connected to the communication bus 71. Examples of these ECUs include multimedia devices such as audio devices and navigation devices.

  In the CAN protocol, the levels of “0” and “1” are detected based on the presence or absence of a voltage difference between two signal lines called CANH (equivalent to 50H, 60H, and 70H) and CANL (equivalent to 50L, 60L, and 70L). Communication is performed using a two-wire differential transmission method.

  The gateway apparatus 10 includes an MPU 11 (communication control unit of the present invention), and transceivers 20, 30, and 40 connected to the MPU 11 via a transmission line TxD, a reception line RxD, and a mode control line STB. The MPU 11 is configured as a well-known one-chip microcomputer including a CPU 11a, a memory 11b which is a nonvolatile memory storing control programs and data, and peripheral circuits (not shown). Various functions of the gateway device 10 are realized by the CPU 11a executing the control program stored in the memory 11b.

  Since the transceiver (generic name of 20, 30, 40, the same applies hereinafter) has the same configuration, the configuration will be described by taking the transceiver 20 as an example. The transceiver 20 includes a transmission / reception circuit 21 (transmission unit 21a, reception unit 21b) and a buffer 22 (storage unit of the present invention). The transmission unit 21 a generates a differential signal based on the transmission signal input from the MPU 11 via the transmission line TxD and sends it to the communication bus 51. In addition, the receiving unit 21b detects the levels “0” and “1” from the differential signal received from the communication bus 51, and outputs the detected signals to the MPU 11 via the reception line RxD.

  The buffer 22 temporarily stores the received signal received at least in the sleep mode. The capacity of the buffer is determined by the data length of the received wakeup data and the number of data to be stored.

  The above-described configuration is “the storage unit is included in the transceiver, and the communication control unit causes the transceiver to read the wake-up data from the storage unit and transmit it to the communication control unit after transition to the normal mode”. . With this configuration, since an abnormality is determined for each communication bus, an increase in current consumption due to wasteful wakeup of control units connected to other communication buses can be suppressed.

  The MPU 11 outputs a signal corresponding to the current operation mode from the mode control line STB. That is, the L level is output in the normal mode that is the normal operation state, and the H level is output in the sleep mode that is the operation state that consumes less power than the normal mode. When the L level is input from the mode control line STB (normal mode), the transceiver 20 operates the entire transceiver 20. On the other hand, when the H level is input from the mode control line STB (sleep mode), at least the receiving unit 21b is operated. The buffer 22 may also be operated.

  In a configuration using LIN as a communication protocol, when an ECU (generic name of 1 to 9, hereinafter the same) wants to wake up a communication bus, a dominant (L level) signal called a wake-up frame is transmitted. The dominant signal is received by the transceiver of the gateway device, and an external interrupt of the CPU and an enable signal of the power supply circuit are controlled to start a wakeup operation.

  The flow of a wake-up operation executed by the gateway device 10 will be described using the network 50 as an example with reference to FIG. It is assumed that the gateway device 10 (at least the transceiver 20) is operating in the sleep mode (S11).

  As a situation in which the gateway device 10 operates in the sleep mode, for example, the vehicle is in a parking state (a state including at least one of engine stop, vehicle speed zero, shift lever parking position, parking brake operation, etc.). Can be mentioned. Therefore, this process may be executed only when the vehicle is parked. This configuration includes “a vehicle state acquisition unit that acquires a vehicle state and a state determination unit that determines whether the vehicle is in a parking state based on the vehicle state, and the communication control unit is when the vehicle is in a parking state. Then, it is determined whether or not the wake-up data is appropriate.

  With the above configuration, it is possible to suppress an increase in current consumption (dark current) of the electronic control device and the control unit substantially only to an increase in current consumption of the electronic control device. In addition, when the vehicle is parked, the abnormality can be detected and the cause can be identified, and the safety of the vehicle or driving can be improved by notifying the user of the situation or performing a degeneracy operation considering safety. be able to.

  The vehicle state can be acquired from, for example, the travel control system ECU (4 to 6) or the body system ECU (7 to 9), and the vehicle state acquired immediately before the gateway device 10 enters the sleep mode is stored in the memory 11b. It is stored and judged using this.

  When the ECUs 1 to 3 on the communication bus 51 transition to the sleep mode, the ECUs 1 to 3 transmit information to that effect (sleep mode transition information) to the gateway device 10. When the MPU 11 receives the sleep mode transition information from all the ECUs (1 to 3) connected to the communication bus 51, the MPU 11 considers that the entire network 50 has transitioned to the sleep mode, and the mode control line STB connected to the transceiver 20. H level is output. When the sleep mode transition information is received from all the ECUs (4-9) on the other communication buses (61, 71), the MPU 11 outputs the H level to the mode control line STB connected to the transceivers 30, 40. After that, the device itself (or the entire gateway device 10) may transition to the sleep mode.

  In the sleep mode, the MPU 11 operates at least the function of detecting the input of the reception line RxD. In the transceiver 20, at least the receiving unit 21b is operating (the same applies to the transceivers 30 and 40). In this state, for example, when the transceiver 20 receives wake-up data (hereinafter abbreviated as “data”) from the communication bus 51 (for example, the ECU 3) (S12: Yes), the transceiver 20 temporarily stores the data in the buffer 22. The information is stored (S13) and output to the MPU 11 via the reception line RxD. At this point, it is not known whether the data is a wakeup signal.

  For example, the MPU 11 detects the presence / absence of data based on the level change of the reception line RxD using an external interrupt function. When the MPU 11 detects data when the MPU 11 is in the sleep mode, the MPU 11 wakes up and starts transition to the normal mode (S14).

  When the transition to the normal mode is completed, the L level (data request signal) is output to the mode control line STB, and the transceiver 20 is woken up. The L level may be output again after outputting the H level for a predetermined time after outputting the L level. This pulse signal becomes a data request signal from the MPU 11 to the transceiver 20. Note that other circuits of the gateway device 10 may remain operating in the sleep mode.

  Next, in the transceiver 20 that detects the change of the mode control line STB from the H level to the L level, the receiving unit 21b reads the data from the buffer 22 (S15) and transmits the data to the MPU 11 (S16). After reading the data, the buffer 22 stores the initial value.

  The above-described configuration is as follows: “The communication control unit and the transceiver are connected by the mode control line, the communication control unit outputs a signal corresponding to the operation state via the mode control line, and the transceiver enters the input operation state. Based on the state of the corresponding signal, the wake-up data is read from the storage unit ”. With this configuration, the configuration of the present invention can be realized at low cost by using an existing signal line.

Next, the MPU 11 analyzes the received data (S17), and determines whether the data is appropriate using at least one of the following (S18).
When the wakeup signal is an L level signal for a predetermined time, the L level time of the data is measured, and when the difference from the predetermined time is within a predetermined threshold, it is determined as a normal wakeup signal.
When the wakeup signal is a signal of a predetermined pattern, the reference pattern and the data pattern stored in the memory 11b are compared, and when both match, it is determined as a normal wakeup signal.

Finally, the MPU 11 executes processing based on the above determination result using at least one of the following (S19).
When the normal wakeup signal is determined, the entire gateway device 10 operates in the normal mode. The transceiver connected to the communication bus that has not transmitted the wakeup signal may not be waked up. Based on the wakeup signal described above, a wakeup request signal or a status inquiry signal is transmitted to another ECU (1 or 2) of the network 50. Further, a wakeup request signal or a status inquiry signal is transmitted to other networks (60, 70) as necessary.
When it is determined that the signal is not a normal wakeup signal, and when the ECU 3 that is the signal transmission source can be specified, a state inquiry signal is transmitted to the ECU 3. Alternatively, data indicating that an abnormality has occurred in the operation of the ECU 3 may be transmitted after wake-up of another ECU (which may include one connected to another network).

  The processes in steps S15 to S19 may be executed only when the gateway apparatus 10 has acquired information indicating that the vehicle is in a parked state immediately before the gateway apparatus 10 transitions to the sleep mode.

  FIG. 3 shows a timing chart of each signal corresponding to the operation of FIG. Until time T0, the gateway device 10 operates in the normal mode. Data (D1 and D2, T1, R1, and R2) according to the situation of each ECU flows through the communication bus 51, the transmission line TxD, and the reception line RxD. The buffer 22 stores an initial value. The MPU 11 outputs L level to the mode control line STB.

  At time T0, the MPU 11 outputs an H level to the mode control line STB, and the gateway device 10 transitions from the normal mode to the sleep mode. Thereafter, when data D3 flows on the communication bus 51 at time T1, the transceiver 20 receives this (R3) and outputs it to the MPU 11 via the reception line RxD. Further, the received data is stored in the buffer 22.

  When the MPU 11 detects the input of the data R3 at time T1, the MPU 11 starts transition from the normal mode to the sleep mode. During the transition, the MPU 11 cannot perform data determination. Then, the L level is output to the mode control line STB (time T2). When the transceiver 20 detects that the mode control line STB has changed to the L level, the transceiver 20 reads the data R3 from the buffer 22 and outputs the data R4 to the MPU 11 (time T3). At this time, the initial value is stored in the buffer. The MPU 11 acquires the data R4 and determines whether the data D3 is normal wakeup data.

  FIG. 4 shows another example of the configuration of the gateway device 10. Since FIG. 4 is a modification of FIG. 1, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 1, a buffer is included in the transceiver, and the transceiver stores wakeup data in the buffer and reads from the buffer. On the other hand, in FIG. 4, the buffer 12 is not included in the transceiver and is connected to the MPU 11, and the MPU 11 stores and reads data. In FIG. 2, step S16 is not executed. That is, data is read from the buffer 12 when the MPU 11 transitions to the normal mode regardless of the operation of the transceiver.

  The configuration of FIG. 4 is “the storage unit is connected to the communication control unit, and the communication control unit starts the transition to the normal mode when receiving the wakeup data, and stores the wakeup data in the storage unit, After the transition to the normal mode, the wake-up data is read from the storage unit ”.

  With this configuration, each transceiver need not have a buffer. There is an advantage that it is not necessary to acquire wakeup data from the transceiver at the time of wakeup. On the other hand, even in the sleep mode, the MPU 11 needs to operate a function capable of writing wakeup data to the buffer in addition to the function of detecting the input of the reception line RxD.

  Although the embodiments of the present invention have been described above, these are merely examples, and the present invention is not limited to these embodiments, and the knowledge of those skilled in the art can be used without departing from the spirit of the claims. Various modifications based on this are possible.

10 Gateway device (electronic control device)
11 MPU (communication control unit)
20, 30, 40 Transceiver 12, 22 Buffer (storage unit)
51, 61, 71 Communication bus ECU1-9 Control unit TxD Transmission line RxD Reception line STB Mode control line

Claims (5)

An electronic control device that communicates with other control units via a communication bus,
A communication control unit and a transceiver connected to each other via a transmission line and a reception line;
A storage unit that stores the received signal received by the transceiver as wake-up data when the electronic control unit operates in a sleep mode, which is an operation state with less power consumption than a normal mode that is a normal operation state;
With
The transceiver sends a transmission signal input from the communication control unit via the transmission line to the communication bus, and receives a reception signal received from the communication bus to the communication control unit via the reception line. Output,
The communication control unit
When the wakeup data is received from the transceiver, the transition from the sleep mode to the normal mode is started.
An electronic control device, wherein after the transition to the normal mode, the wakeup data is acquired from the storage unit, and it is determined whether or not the wakeup data is appropriate. The storage unit is included in the transceiver,
The electronic control device according to claim 1, wherein the communication control unit causes the transceiver to read the wakeup data from the storage unit and transmit the wakeup data to the communication control unit after transitioning to the normal mode. The communication control unit and the transceiver are connected by a mode control line,
The communication control unit outputs a signal corresponding to the operation state via the mode control line,
The electronic control device according to claim 2, wherein the transceiver reads the wakeup data from the storage unit based on a state of a signal corresponding to the input operation state. The storage unit is connected to the communication control unit,
When the communication control unit receives the wakeup data, the communication control unit starts transition to the normal mode, and stores the wakeup data in the storage unit,
The electronic control device according to claim 1, wherein the wakeup data is read from the storage unit after the transition to the normal mode.   The electronic control device is a vehicle gateway device in which a plurality of networks in which the control units are connected by the communication bus are formed and data is relayed between the plurality of networks. The electronic control device according to claim 1.

Images