JP5783088B2 - Vehicle control system - Google Patents

Description

  The present invention relates to a vehicle control system that controls an internal combustion engine mounted on a vehicle.

  2. Description of the Related Art Conventionally, as a control system for controlling an internal combustion engine (engine) mounted on a vehicle, a system that detects a pressure fluctuation mode related to fuel injection based on an output from a pressure sensor that measures fuel pressure is known. (See Patent Document 1). The pressure fluctuation mode varies depending on the type of injection system such as an injector or a fuel pump. The detection result of the pressure fluctuation mode is used, for example, for performing optimal fuel injection control in accordance with the characteristics of the injection system.

JP 2008-144749

  By the way, as a method of constructing a control system that performs fuel injection control according to the characteristics of the injection system, a fuel injection controller is provided separately from the engine control device, and the engine control device executes general control, and the injection control is performed. A method for constructing the control system so that the fuel injection controller executes control depending on the characteristics of the system is conceivable. According to this control system, it is possible to efficiently construct a control system suitable for various injection systems by changing the fuel injection controller.

  However, when the internal combustion engine is controlled by the cooperation of a plurality of vehicle control devices (according to the above example, the engine control device and the fuel injection controller), each vehicle control device performs control according to the change in the crank angle. In order to be able to do so, it is necessary to input a crank angle signal to each of the vehicle control devices. When the output signal of the crank angle sensor is input to each vehicle control device as the crank angle signal, it is necessary to shape the waveform of the output signal of the crank angle sensor and input this to each vehicle control device. It is necessary to provide an input circuit for waveform shaping for each vehicle control device.

  The present invention has been made in view of these problems, and each of the vehicle control devices can control other vehicle controls without providing an input circuit for inputting the output signal of the crank angle sensor to each of the vehicle control devices. An object of the present invention is to provide a technique capable of executing appropriate control of an internal combustion engine in accordance with a change in crank angle in cooperation with an apparatus.

This onset Ming vehicle control system has been proposed in order to achieve the above object, comprises a plurality of vehicle control device connected to the communication line in common, the control of the internal combustion engine mounted on the vehicle, accompanied by the transmission and reception of data This is realized by cooperation of the plurality of vehicle control devices. In this vehicle control system, the first vehicle control device and the second vehicle control device different from the first vehicle control device are configured as follows.

  The first vehicle control device includes crank angle signal input means, pseudo signal output means, and first data communication means. The crank angle signal input means inputs a crank angle signal as a pulse signal in accordance with a change in the crank angle in the internal combustion engine, and the pseudo signal output means receives the crank angle signal every time the crank angle signal is input by the crank angle signal input means. A pseudo crank angle signal, which is a pseudo signal of the signal, is output to the communication line, and the first data communication means stops outputting the pseudo crank angle signal to the communication line based on the input interval of the crank angle signal, Data is transmitted via the communication line to the second vehicle control device during a period in which it is estimated that no signal is output to the communication line.

  On the other hand, the second vehicle control device includes pseudo signal input detection means, crank angle identification means, and second data communication means. The pseudo signal input detecting means detects the input of the pseudo crank angle signal input via the communication line, and the crank angle specifying means is based on the detection result by the pseudo signal input detecting means. The second data communication means receives data transmitted from the first vehicle control device via the communication line.

  Thus, in the vehicle control system of the present invention, the pseudo crank angle signal corresponding to the crank angle signal is transmitted using the communication line used for transmission / reception of data necessary for vehicle control. Therefore, according to this vehicle control system, it is not necessary to provide an input circuit for inputting the output signal of the crank angle sensor in each of the second vehicle control devices, and further, a signal line dedicated for crank angle signal transmission is installed. There is no need. That is, according to the vehicle control system of the present invention, even if each of the vehicle control devices is not provided with an input circuit from the crank angle sensor, in the plurality of vehicle control devices, appropriate vehicle control corresponding to the change of the crank angle is performed. Can be executed. Therefore, according to the present invention, an excellent system can be constructed as a vehicle control system for controlling the internal combustion engine.

By the way, the first and second vehicle control devices can be configured to transmit and receive data bidirectionally. For example, the second data communication means communicates the pseudo crank angle signal after stopping the output of the pseudo crank angle signal to the communication line based on the input interval of the pseudo crank angle signal specified from the detection result of the pseudo signal input detection means. The data can be configured to be transmitted to the first vehicle control device via the communication line during the period estimated not to be output to the line, and the first data communication unit can thus be configured to communicate via the communication line. Te Ru can be configured to receive data transmitted from the second vehicle control apparatus.

Further, in consideration of a case where the communication is not full-duplex communication or the like, in order to prevent a communication collision from occurring, the first and second data communication means stop the pseudo crank angle signal output to the communication line. the signal there is a time period in a by sending the data to the own device authority is presumed not to be output to the communication line period, Ru can be configured to transmit the data.

The presence / absence of transmission authority can be determined, for example, by the following method. That is, when the first and second data communication means have the transmission authority, the first and second data communication means transmit the transmission authority data in which the identification code of the vehicle control apparatus to which the transmission authority is given next is written as one of the data. When the transmission authority data in which the identification code of the device is written is received via the communication line, it is estimated that the pseudo crank angle signal is not output to the communication line after the output of the pseudo crank angle signal generated after the reception is stopped. the that period, Ru can be configured to determine that period there is transmission permission data to the own device. In this way, if the vehicle control device having the transmission authority grants the transmission authority to the next vehicle control device, the communication collision is suppressed, and data is appropriately transmitted between the first and second vehicle control devices. You can send and receive.

The operation of transmitting the data during a period in which the pseudo crank angle signal is not output to the communication line is performed in the range of the number of data that can be transmitted in the period in which the pseudo crank angle signal is not output to the communication line. an inner, determines the number of data to be transmitted, after the output stopping of the pseudo crank angle signal to the communication line, Ru can be realized by the operation of sending the determined number of data.

  In addition, the first vehicle control device has storage means for storing, for each rotational speed of the internal combustion engine, a table in which the type and number of data to be transmitted for each input of the crank angle signal is stored. By transmitting data, it may be configured to transmit necessary data to the second vehicle control device during a period in which it is estimated that the pseudo crank angle signal is not output to the communication line.

That is, for each input of the crank angle signal, the first data communication means refers to the table of the rotational speed of the internal combustion engine corresponding to the input interval of the crank angle signal, and after stopping the output of the pseudo crank angle signal to the communication line, By transmitting the data of the type and number according to the table to the second vehicle control device via the communication line, the data is transmitted via the communication line during the period during which it is estimated that the pseudo crank angle signal is not output to the communication line. It is a configuration that transmits the data to the second vehicle control device has good.

  In addition, when data is transmitted and received bidirectionally between the first and second vehicle control devices, a table for each number of revolutions of the internal combustion engine is stored for each of the first and second vehicle control devices. Storage means can be provided, and as the table, in addition to the type and number of data to be transmitted for each input of the crank angle signal, data in which the transmission source of this data is defined can be provided.

The first data communication means refers to a table of the rotational speed of the internal combustion engine corresponding to the input interval of the crank angle signal for each input of the crank angle signal, and after stopping the output of the pseudo crank angle signal to the communication line, When the transmission source according to the table is its own device, the type and number of data according to the table can be transmitted to the second vehicle control device via the communication line. Similarly, the second data communication unit is configured to generate an internal combustion engine corresponding to the input interval of the pseudo crank angle signal every time the pseudo signal input detection unit detects the input of the pseudo crank angle signal due to the input of the crank angle signal. After referring to the engine speed table and stopping the output of the pseudo crank angle signal, if the transmission source according to the table is its own device, the data of the type and number according to the table are first sent via the communication line. Ru can be configured to be transmitted to the vehicle controller.

  If data is transmitted and received between the first and second vehicle control devices in this way, data is appropriately transmitted and received within a period during which the pseudo crank angle signal is not output to the communication line while preventing a communication collision. be able to.

  In addition, the pseudo signal output means outputs the pseudo crank angle signal to the communication line by switching the signal level of the communication line to the active level, and the pseudo signal input detection means sets the signal level on the communication line to the active level. When a changing event occurs, the input of the pseudo crank angle signal can be detected at that time. By configuring the vehicle control system in this way, it is possible to detect the input of the pseudo crank angle signal in the second vehicle control device with a small time lag from the input timing of the crank angle signal in the first vehicle control device. In the second vehicle control device, the crank angle at each time can be specified with the same accuracy as the first vehicle control device.

  Further, when detecting the input of the pseudo crank angle signal in this way, the pseudo signal input detecting means is set to the following so that the communication signal output to the communication line at the time of data transmission is not detected as the pseudo crank angle signal. It is good to be configured as follows.

That is, the pseudo signal input detection means detects the input of the pseudo crank angle signal at the time when the event that the signal level on the communication line changes to the active level occurs, while the occurrence of the event that triggered the detection occurs. The operation for detecting the input of the pseudo crank angle signal is invalidated from the time point until the end of the period when it is estimated that the pseudo crank angle signal after the stop of the output of the pseudo crank angle signal to the communication line is not output to the communication line. it allows each time the pseudo crank angle signal is inputted, it is a good test is a configuration that detects an input of the pseudo crank angle signal.

  As described above, data transmission is performed during a period during which it is estimated that the pseudo crank angle signal is not output to the communication line after the output of the pseudo crank angle signal is stopped. During this period, the input of the pseudo crank angle signal is detected. If the operation to be performed is invalidated, it is not necessary to detect the reception of the communication signal as the input of the pseudo crank angle signal, and the pseudo crank angle signal can be appropriately transmitted to the second vehicle control device.

In order to prevent the pseudo crank angle signal from being misinterpreted as a communication signal in the second data communication means, the vehicle control system can be configured as follows. For example, asynchronous communication is performed between the first data communication unit and the second data communication unit, and when transmitting data, start bits before and after a fixed-length bit string that is one unit of data. In an environment in which a communication signal including a stop bit is output to the communication line, the pseudo signal output means is configured to communicate the communication line for a certain time longer than the time length of the communication signal from the start bit to the stop bit for each input of the crank angle signal. by switching the signal level to the active level, Ru can be configured to output a pseudo crank angle signal is distinguished from the communication signal to the communication line. By outputting such a pseudo crank angle signal that does not conform to the communication signal, the second data communication means does not need to misinterpret the pseudo crank angle signal as a communication signal, and between the first and second vehicle control devices. Then, data can be transmitted and received appropriately.

The vehicle control system may be configured as follows. That is, the second data communication means outputs a response signal to the first vehicle control device via the communication line when the pseudo signal input detecting means detects the input of the pseudo crank angle signal, and It starts waiting operation, the first data communication means, but it may also be a configuration for performing a transmission operation of data to the second vehicle control device after the input of the response signal. According to this configuration, the first data communication means in the first vehicle control device can start the data transmission operation after confirming that the second vehicle control device can receive data. The failure of data reception in the second vehicle control device can be suppressed, and the communication reliability can be improved.

1 is a block diagram illustrating a configuration of a vehicle control system 1. FIG. It is a time chart which shows the change of various signals and operation | movement in a 1st Example. It is a figure which shows the outline | summary of the process which the microcomputers 20 and 40 perform. It is a flowchart showing the communication control process which the calculating part 21 performs. It is a flowchart showing the regular processing which the calculating parts 21 and 41 perform. It is a flowchart showing the transmission process which the calculating parts 21 and 41 perform. It is a time chart which shows the change of various signals at the time of an engine stall, and operation. It is a flowchart showing the reception process which the calculating parts 21 and 41 perform. It is a time chart which shows the change of various signals at the time of reception error, and operation. It is a flowchart showing the communication control process which the calculating part 41 performs. It is a time chart which shows the change of various signals and operation | movement in a 2nd Example. It is a figure showing the structure of the schedule data for every engine speed. It is a flowchart showing the communication control process which the calculating part 21 performs. It is a flowchart showing the regular processing which the calculating parts 21 and 41 perform. It is a flowchart showing the transmission process which the calculating parts 21 and 41 perform. It is a flowchart showing the reception process which the calculating parts 21 and 41 perform. It is a flowchart showing the communication control process which the calculating part 41 performs. It is a block diagram showing the structure of the vehicle control system 1 of a modification.

Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
A vehicle control system 1 according to this embodiment shown in FIG. 1 is a control system that controls an internal combustion engine (engine) mounted on a vehicle. Specifically, fuel injection from an injector 3 installed in each cylinder is performed. It is a system to control. The vehicle control system 1 is configured such that the main unit 10 and the subunit 30 are connected to each other through a common communication line LN so that data communication is possible. The fuel injection control is realized by the cooperation of 30.

  Specifically, the communication line LN is configured as a single communication line, and data communication between the main unit 10 and the subunit 30 is realized by serial communication using a single end signal. The communication line LN is provided with a signal line for clock signal transmission and other control lines as necessary.

  The main unit 10 is a so-called engine ECU, and is configured as a vehicle control device that performs overall control of the internal combustion engine. The main unit 10 includes an input circuit 11, a pseudo crank angle signal generation circuit 15, and a microcomputer (hereinafter simply referred to as “microcomputer”) 20.

  The input circuit 11 shapes the output signal of the crank angle sensor SN attached to the crankshaft of the internal combustion engine, and forms a crank angle signal as a pulse signal corresponding to a change in the crank angle (see “ CRNK "). The crank angle sensor SN is composed of, for example, a rotary encoder, and outputs a rectangular wave or a sine wave corresponding to a change in the crank angle. This waveform varies depending on the manufacturer and product. The input circuit 11 shapes the output signal of the crank angle sensor SN that outputs a different waveform for each product, and each time the crank angle changes by a predetermined angle (for example, every 6 degrees), the input crank 11 An angle signal is input to the microcomputer 20.

  On the other hand, when the crank angle signal (Hi) is input from the input circuit 11, the pseudo crank angle signal generation circuit 15 inputs the signal level of the communication line LN for a predetermined time from the input start timing as shown in FIG. By switching from the active level (Hi) to the active level (Lo), a pseudo crank angle signal (“Pcr” shown in FIGS. 1 and 2) which is a pseudo signal of the crank angle signal is output to the communication line LN. . Specifically, the pseudo crank angle signal continues the active level (Lo) for a time that does not occur in the communication signal output to the communication line LN in the serial communication performed between the main unit 10 and the subunit 30. The signal is output to the communication line LN. According to the example shown in FIG. 2, the pseudo crank angle signal continues the time active level (Lo) for 10 bits corresponding to the length of the communication signal (frame) including the start bit and the stop bit used in data communication. To be output to the communication line LN.

  The microcomputer 20 has a hardware configuration similar to that of a known microcomputer, and includes a calculation unit 21 that executes processing according to various programs including control of the internal combustion engine, a transmission / reception circuit 22 connected to the communication line LN, and a direct A memory access controller (DMAC) 23, a RAM 25 that is used as a temporary storage memory when a program is executed by the calculation unit 21, a ROM 26 that stores various programs executed by the calculation unit 21, and an edge detection circuit 27 are provided.

  The transmission / reception circuit 22 is for data communication with the subunit 30 via the communication line LN, and performs data communication with another device (subunit 30) connected to the communication line LN by asynchronous serial communication. Is. As is well known, in asynchronous serial communication, for each unit of data (one word), a start bit is added to the beginning of this data, and a stop signal is added to the end of this data. (Frame) is output to the communication line LN.

  In the present embodiment, a communication signal in which a start bit for one bit and a stop bit for one bit are added for each 8-bit data is output to the communication line LN. Therefore, one unit of communication signal (one frame) is configured as a signal of 10 bits. The start bit and the stop bit are different from each other. According to the example shown in FIG. 2, the start bit takes Lo which is an active level, and the stop bit takes Hi which is an inactive level.

  That is, a communication signal used for serial communication does not continuously take an active level (Lo) for a time of 10 bits or more. In this embodiment, for this reason, the pseudo crank angle signal is defined as a 10-bit signal as described above.

  The transmission / reception circuit 22 transmits data to be transmitted stored in a built-in transmission buffer (not shown) by the communication method described above, and accumulates data received via the communication line LN in a built-in reception buffer (not shown). When the stop bit value of the reception signal is not a normal value, the transmission / reception circuit 22 detects this as a reception error. Various reception errors detected by the transmission / reception circuit 22 including this type of reception error are notified to the arithmetic unit 21 by an interrupt (hereinafter referred to as “reception error interrupt”).

  The DMAC 23 directly realizes data transfer between the transmission / reception circuit 22 and the RAM 25 without requiring reading / writing by the arithmetic unit 21. When a transfer command is input from the arithmetic unit 21, the DMAC 23 reads data stored in a predetermined transmission memory area of the RAM 25 and sequentially writes the data in the transmission buffer of the transmission / reception circuit 22. Thereby, the data is output to the communication line LN as the communication signal via the transmission / reception circuit 22. In response to a request from the transmission / reception circuit 22, the DMAC 23 reads the reception data stored in the reception buffer of the transmission / reception circuit 22 and writes it in a predetermined reception memory area of the RAM 25.

  In addition, the edge detection circuit 27 is configured by, for example, an input capture, and is connected to the output terminal of the input circuit 11. When a crank angle signal is input from the input circuit 11, the signal edge (Lo to Hi) is detected. The signal edge) is detected, and an interrupt to the calculation unit 21 is generated for each detection. The edge detection circuit 27 can be configured to include a plurality of input channels as in the known input capture. Although FIG. 1 shows inputs from a plurality of paths to the edge detection circuit 27, the input path indicated by a broken line shows the configuration of a second embodiment described later. The edge detection circuit of this embodiment Note that no such input path is provided for 27.

  Next, the configuration of the subunit 30 will be described. The sub unit 30 is a fuel injection controller that realizes detailed fuel injection control according to the characteristics of the injection system in cooperation with the main unit 10 (engine ECU), and includes a microcomputer 40 and a drive circuit 50. The microcomputer 40 includes a calculation unit 41 that executes processing according to various programs including fuel injection control, a transmission / reception circuit 42, a DMAC 43, a RAM 45 that is used as a temporary storage memory when the calculation unit 41 executes a program, A ROM 46 that stores various programs executed by the unit 41, an edge detection circuit 47, and an output port 49 are provided.

  The transmission / reception circuit 42 is connected to the same communication line LN as the transmission / reception circuit 22 of the main unit 10, has the same configuration as the transmission / reception circuit 22 of the main unit 10, and is connected to the communication line LN by the same communication method. 10 for data communication. That is, similar to the transmission / reception circuit 22 of the main unit 10, the transmission / reception circuit 42 converts the transmission target data stored in a built-in transmission buffer (not shown) into a communication signal (frame) including the start bit and stop bit. To the communication line LN and transmit the communication signal to the other party. When the communication signal (frame) is received, data included in the communication signal is stored in a built-in reception buffer (not shown) as reception data by serial communication. When the stop bit value of the received signal is not a normal value, the transmission / reception circuit 42 detects this as a reception error. Various reception errors detected by the transmission / reception circuit 42 including this type of reception error are notified to the arithmetic unit 41 by an interrupt (reception error interrupt).

  Further, the DMAC 43 performs data transfer between the transmission / reception circuit 42 and the RAM 45 as in the DMAC 23. That is, when a transfer command is input from the arithmetic unit 41, the DMAC 43 reads data to be transmitted stored in the transmission memory area of the RAM 45 and sequentially writes it in the transmission buffer of the transmission / reception circuit 42. In response to a request from the transmission / reception circuit 42, the reception data stored in the reception buffer of the transmission / reception circuit 42 is sequentially read out and written in the reception memory area of the RAM 45.

  In addition, the edge detection circuit 47 is configured by, for example, an input capture as in the main unit 10, and when a pseudo crank angle signal is input from the communication line LN, the edge detection circuit 47 detects the signal edge, and for each detection, An interrupt to the calculation unit 41 is generated. Specifically, when the edge detection circuit 47 detects a signal edge where the signal level of the communication line LN changes from the inactive level (Hi) to the active level (Lo), the edge detection circuit 47 regards this as an input of the pseudo crank angle signal. Generate an interrupt.

  However, when the interrupt mask for the pseudo crank angle signal is set, the edge detection circuit 47 prohibits the generation of an interrupt due to the detection of the signal edge until the interrupt mask is canceled, thereby causing the arithmetic unit 41 to Disable signal edge detection. The interrupt mask is set by the calculation unit 41 so as to be effective during a period in which data communication is performed between the transmission / reception circuits 22 and 42 (details will be described later). By setting / releasing the interrupt mask as described above, the edge detection circuit 47 generates an interrupt with respect to the input of the pseudo crank angle signal among the pseudo crank angle signal and the communication signal transmitted through the communication line LN, and the pseudo crank angle The calculation unit 41 is notified of the signal input.

  Further, a drive circuit 50 is connected to the output port 49, and the calculation unit 41 of the microcomputer 40 inputs a control signal to the drive circuit 50 via the output port 49, and thereby via the drive circuit 50. The drive control of the injector 3 is performed, and the fuel injection by the injector 3 is controlled. For example, the injection timing and the injection time are controlled. An output signal from a sensor (such as a pressure sensor) (not shown) included in the injector 3 is input to the calculation unit 41 through an A / D converter (not shown) included in the microcomputer 40 and used for driving control of the injector 3. In FIG. 1, the connection path from the output port 49 to the communication line LN is indicated by a broken line. However, it should be noted that this configuration shows a configuration of a second embodiment to be described later. .

Subsequently, an outline of operations of the main unit 10 and the subunit 30 will be described with reference to FIGS. 2 and 3. In the main unit 10, when the crank angle signal is input from the input circuit 11, the arithmetic unit 21 performs the crank angle update processing PR <b> 1 and the communication control processing PR <b> 2 shown in FIG. 3 in response to the interrupt generated from the edge detection circuit 27. In the crank angle update process PR1, the crank angle stored and held in the main unit 10 is updated based on the input crank angle signal. This crank angle information is used for controlling the internal combustion engine in the main unit 10.
Further, in the communication control process PR2, it is determined whether or not the data transmission authority is in the own unit. If the data transmission authority is in the own unit, the data transmission by the transmission process is permitted to generate the pseudo crank angle signal. After the output of the pseudo crank angle signal by the circuit 15 is completed, data necessary for fuel injection control is transmitted to the subunit 30. As data transmitted here, the data in which the fuel injection timing and the injection amount of each cylinder were described can be mentioned as an example.

On the other hand, in the subunit 30, when the pseudo crank angle signal is input through the communication line LN, the calculation unit 41 responds to the interrupt generated from the edge detection circuit 47, as shown in FIG. The communication control process PR4 is executed, and in the crank angle update process PR3, the crank angle stored and held in the subunit 30 is updated based on the input pseudo crank angle signal. This crank angle information is used for control of the internal combustion engine (fuel injection control) in the subunit 30.
Further, in the communication control process PR4, while setting an interrupt mask for the pseudo crank angle signal, a timer for canceling the interrupt mask is set for the edge detection circuit 47 by a method described later, so that the pseudo crank angle signal is The edge detection circuit 47 cancels the interrupt mask before the time estimated to be input. Thereby, the arithmetic unit 41 of the subunit 30 prevents the interruption from the edge detection circuit 47 caused by the change in the signal level of the communication line LN due to the communication signal, while at the time of inputting the pseudo crank angle signal, The edge detection circuit 47 is set so that the interrupt occurs. Then, the arithmetic unit 41 of the subunit 30 receives the data transmitted from the main unit 10 via the transmission / reception circuit 42 while the interrupt mask is continued.

  In addition, in the communication control process PR4, it is determined whether or not the data transmission authority is in the own unit. If the data transmission authority is in the own unit, the data transmission by the transmission process is permitted and the pseudo crank angle signal is transmitted. After the output is completed, data necessary for fuel injection control is transmitted to the main unit 10. As data transmitted here, the result of fuel injection by the injector 3 of each cylinder (for example, fuel injection time) and the detection result by the sensor mounted on the injector 3 (for example, the pressure detection value by the pressure sensor) are described. Data can be cited as an example. The arithmetic unit 21 of the main unit 10 receives the data transmitted from the subunit 30 in this way through the transmission / reception circuit 22 while the interrupt mask is continued.

  Next, details of the communication control process PR2 executed by the arithmetic unit 21 of the main unit 10 in response to an interrupt generated from the edge detection circuit 27 when the crank angle signal is input will be described with reference to FIG. When the processing unit 21 of the main unit 10 starts the process shown in FIG. 4, it calculates the crank angle signal input interval as the inter-crank time (S110). Specifically, the time difference between the current crank angle signal input start time and the previous crank angle signal input start time is calculated as the inter-crank time.

  Thereafter, the calculation unit 21 waits until the pseudo crank angle signal generation by the pseudo crank angle signal generation circuit 15 is completed (S120), and when the output of the pseudo crank angle signal is completed, the process proceeds to S130. Whether or not the output of the pseudo crank angle signal is completed can be determined, for example, based on the elapsed time from the input start time of the crank angle signal.

  If transfering to S130, the calculating part 21 will judge whether a transmission unit is an own unit by referring the setting value of a transmission unit. The transmission unit here refers to a vehicle control device (main unit 10 or subunit 30) having the authority to transmit data by serial communication, and the setting value of the transmission unit is the identification of the vehicle control device having the data transmission authority. Indicates the code. The set value of the transmission unit is initialized to the identification code of the main unit 10 at the time of activation in each of the main unit 10 and the subunit 30.

  If it is determined that the transmitting unit is the own unit (Yes in S130), the calculation unit 21 starts the output of the pseudo crank angle signal to the communication line LN triggered by the generation of the current crank angle signal. In step S140, it is determined whether or not the interrupt mask is not released at 30 (see FIG. 9). The duration of the interrupt mask is determined by a predetermined rule in the subunit 30 based on the input interval of the immediately preceding pseudo crank angle signal. Such a state in which the interrupt mask is not released can occur when the input interval of the pseudo crank angle signal is suddenly shortened due to a sudden change in engine rotation.

  The main unit 10 specifies the duration of such an interrupt mask according to the above rule from the inter-crank time calculated in the previous S110 corresponding to the input interval of the pseudo crank angle signal. Then, it is determined from the duration of the interrupt mask specified in this way whether or not the interrupt mask has not been released in the subunit 30.

  For example, if the duration of the specified interrupt mask is longer than the inter-crank time calculated in S110 of this time, the pseudo crank angle signal is started in the subunit 30 at the start of output of the pseudo crank angle signal due to generation of the current crank angle signal. It is determined that the interrupt mask for the corner signal has not been released.

  The occurrence of such a state where the interrupt mask is not released can be avoided by setting a short interrupt mask duration in the subunit 30. However, according to the present embodiment, the communication signal is transmitted only during the period in which the interrupt mask is set so that the edge detection circuit 47 does not generate the interrupt due to the communication signal. For this reason, if the interrupt mask duration is set short, there is a disadvantage that the time that can be secured for data communication is shortened.

  If it is determined that the interrupt mask has not been released (Yes in S140), the calculation unit 21 ends the communication control process PR2 without executing the processes of S150 and S160. Data communication triggered by the input of the current crank angle signal is prohibited. Here, the reason why data communication is prohibited is that, in the situation where the above-described state occurs, even if data communication is started, the subunit 30 may not be able to normally receive data.

  On the other hand, if it is determined that the interrupt mask has been released (No in S140), the calculation unit 21 receives the pseudo crank angle signal in this time based on the inter-crank time calculated in S110. A control data group to be transmitted to the subunit 30 (hereinafter referred to as “transmission target data group”) so that the duration of the interrupt mask to be set is specified and the data transmission is completed while the interrupt mask continues. Is determined (S150). Specifically, the number and type of control data to be transmitted to the subunit 30 are determined. The control data is data necessary for the fuel injection control. Thereafter, the calculation unit 21 sets the transmission permission flag of the own unit to ON, thereby permitting data transmission by the transmission process shown in FIG. 6 (S160), and ends the communication control process PR2. With this setting, as will be described later, the number and type of control data determined in S150 are transmitted from the main unit 10 to the subunit 30 via the transmission / reception circuit 22.

  The control data to be transmitted from the main unit 10 to the subunit 30 and the control data to be transmitted from the subunit 30 to the main unit 10 are generally determined according to the crank angle, but in this embodiment, a crank angle signal is generated. The control data to be transmitted in the angle unit to be transmitted is not defined in detail, but the control data to be transmitted in an angle range wider than the angle unit is defined.

  That is, in S150, among the control data groups determined as control data to be transmitted within such an angle range, the control data group to be transmitted according to the input of the current crank angle signal has been transmitted so far. This is determined based on the control data group, the control data group not yet transmitted, and the duration of the current interrupt mask. In this case, as will be described later, considering that it is necessary to transmit the identifier and transmission authority data (see FIG. 6) together with the control data group, a series of data communication including these is performed as an interrupt mask. The transmission target data group is determined so as to end within the continuation time.

  Next, the regular processing shown in FIG. 5 executed by the arithmetic unit 21 of the main unit 10 every predetermined time will be described separately from the communication control processing PR2. This scheduled process is executed at a time interval sufficiently shorter than the minimum value of the time between cranks that can occur in the host vehicle in which the vehicle control system 1 is constructed, for example.

  When the scheduled processing shown in FIG. 5 is started, the calculation unit 21 determines whether or not the output of the pseudo crank angle signal to the communication line LN (that is, the output for 10 bits) has been completed (S210). When it is determined that the pseudo crank angle signal has been output and the output of the pseudo crank angle signal has not been completed (No in S210), the scheduled processing is terminated. On the other hand, if it is determined that the output of the pseudo crank angle signal is completed (Yes in S210), it is determined whether or not the host vehicle is stalled (S220). If it is determined that the engine is not stalled (No in S220), the process proceeds to S280, and the transmission process shown in FIG. 6 is executed.

  Details of the transmission process shown in FIG. 6 will be described here. When the transmission process is started, the calculation unit 21 determines whether or not the transmission permission flag of the own unit is set on (S310), and determines that the transmission permission flag is set off (in S310). No) By terminating the transmission process without executing the processes of S320 to S350, the transmission process is terminated substantially without performing any process for data transmission.

  On the other hand, if it is determined that the transmission permission flag is set to ON (Yes in S310), the process proceeds to S320, and the process of S320 and S330 is repeatedly executed, whereby the transmission target data group determined in S150 is stored in the RAM 25. Write in the transmission memory area in the order of transmission.

  Specifically, in S320, the calculation unit 21 determines whether or not all the transmission target data (control data) has been written in the transmission memory area of the RAM 25, and determines that it has not been written (No in S320), the process proceeds to S330. Then, the transmission target data with the youngest transmission order among the transmission target data not written in the transmission memory area is written in the transmission memory area together with the identifier of this data. In this embodiment, the identifier and the control data are each configured as 8-bit data that can be transmitted with one unit of communication signal (that is, in one frame). As shown in FIG. Are output to the communication line LN as communication signals including a start bit and a stop bit, respectively, in the order of identifier and control data. In S330, a set of identifier and control data starting from this identifier is written in the transmission memory area. Then, when the process of S330 is completed, the process returns to S320. The calculation unit 21 repeats such processing to write each of the transmission target data in the transmission memory area of the RAM 25 in the order of transmission.

  If it is determined that all of the transmission target data has been written in the transmission memory area of the RAM 25 (Yes in S320), the calculation unit 21 transmits the identification code of the vehicle control device to be set next in the transmission unit. Authority data is generated and written in the transmission memory area together with the identifier of the transmission authority data (S340). It should be noted that the “vehicle control apparatus to be set next as the transmission unit” mentioned here may be itself (main unit 10). Information on the vehicle control device to be set in the transmission unit is stored in advance in the ROM by each vehicle control device (main unit 10 and subunit 30) in association with the information on the data to be transmitted according to the crank angle described above. . In other words, the transmission authority data is configured as 8-bit data that can be transmitted as a communication signal for one unit, like the control data.

  The calculation unit 21 is a group of communication data (that is, a group of identifiers, control data, and transmission authority data) so that the transmission authority data is transmitted after the transmission of the transmission target data group by the processes of S320 to S340 described above. Are arranged and written to the transmission memory area. Thereafter, by inputting a transfer command to the DMAC 23 (S350), a group of communication data written in the transmission memory area in the DMAC 23 is transferred to the transmission buffer of the transmission / reception circuit 22, and the communication circuit 22 transmits these communication data. A group of data is transmitted to the subunit 30 in order.

When the calculation unit 21 of the main unit 10 finishes the transmission process described above in S280 (see FIG. 5), the transmission permission flag is set to OFF (S290), and the scheduled process ends.
On the other hand, when determining that the engine stall is in S220, the arithmetic unit 21 determines whether or not it is immediately after the engine stall occurs (S230). Here, when it is determined that the engine stall is not being performed in the previous scheduled process, and it is determined that the engine stall is being performed in the current scheduled process, it is determined that the engine stall has just occurred (S230). If it is determined that the engine stall has just occurred (Yes in S230), the process proceeds to S250, and the transmission unit is updated to the main unit 10.

  Thereafter, the calculation unit 21 proceeds to S260, determines whether or not the transmission unit is the own unit, and determines that the transmission unit is the own unit (Yes in S260), the control data necessary for dealing with the engine stall The group is determined as a transmission target data group (S270), the transmission permission flag of the own unit is set to ON (S275), and the processing after S280 is executed, so in S330 of the transmission processing, the transmission determined in S270 The target data is sequentially written into the transmission memory area, and these are transmitted to the subunit 30 via the DMAC 23 and the transmission / reception circuit 22. On the other hand, if it is determined that the transmitting unit is not the own unit (No in S260), the scheduled processing is terminated.

  In addition, if it is determined in S230 that it is not immediately after the occurrence of the engine stall, the calculation unit 21 skips the process of S250 and executes the processes after S260. As a result, as shown in FIG. 7, the calculation unit 21 performs data communication with the subunit 30 until the internal combustion engine is restarted and the input of the crank angle signal is restarted. Run continuously between.

  On the other hand, the arithmetic unit 21 of the main unit 10 performs the reception process shown in FIG. 8 in response to the reception interrupt or the reception error interrupt that occurs when a series of data reception by the data communication performed during the interruption mask is continued. By executing the above, a series of reception data groups transferred from the reception buffer of the transmission / reception circuit 22 to the reception memory area of the RAM 25 are read in the order of reception for each set of identifier and data body (control data or transmission authority data). A process corresponding to the read data is executed.

. The reception interrupt may be generated as a timer interrupt at the end timing of the data communication period (continuation period of the interrupt mask) or may be generated due to reception of the number of pieces of data to be received. However, when a reception interrupt is generated depending on the number of received data, the determination algorithm of the transmission target data group in the main unit 10 and the subunit 30 is shared between the main unit 10 and the subunit 30.

  Specifically, when the reception process shown in FIG. 8 is started, the arithmetic unit 21 determines whether or not a reception error has occurred in the transmission / reception circuit 22 (S410). If it is determined that no reception error has occurred (No in S410), a set (data set) of an identifier and a data body in the reception data group stored in the reception memory area is read from the reception memory area ( S420) Based on the identifier of the read data set, it is determined whether or not this data set is a data set including transmission authority data (S430).

  If it is determined that the data set includes control data instead of the data set including transmission authority data (No in S430), the type of control data included in the data set is determined from the identifier included in the data set. This control data is then provided to a control task related to fuel injection control that requires this control data. Thereby, the control data is captured (S440). However, since this reception process also handles data transmitted from the own unit, the received control data may not be necessary in the own unit. In this case, the control data may be discarded in S440.

  After the process of S440, the calculation unit 21 determines whether or not all the received data stored in the reception memory area has been read (S450). If the data has been read, the reception process is terminated. If not, the process proceeds to S420. Transition.

  On the other hand, when it is determined that the read data set is a data set for transmission authority data (Yes in S430), the calculation unit 21 controls the vehicle control that the transmission authority data indicates the set value of the transmission unit stored in its own unit. By setting the identification code of the device, the next transmission unit is set to the vehicle control device (main unit 10 or subunit 30) notified by the transmission authority data (S460). Here, there is a possibility that the transmission authority data is the transmission authority data transmitted from the own unit. In this case as well, the setting value of the transmission unit stored in the own unit is updated based on the transmission authority data. When the process in S460 is completed in this way, the reception process is ended.

  In addition, if it is determined that the reception error has occurred (Yes in S410), the arithmetic unit 21 proceeds to S415, and the generated reception error is continuing the interrupt mask in the subunit 30 (in other words, During the data communication), the pseudo crank angle signal starts to be output (see FIG. 9), thereby determining whether or not the type of reception error is caused by the stop bit not being a normal value (S415). ).

  If it is determined that the reception error is this type of reception error (Yes in S415), the process proceeds to S470, and within the reception data group written in the reception memory area of the RAM 25, normal reception data is determined from the error occurrence timing. Received data determined to be received, and received data determined to be not normal received data are discarded. In S470, the same processing as in S420 to S460 can be performed on a data set including control data that can be normally received. Thereafter, the reception process ends. Note that steps indicated by broken lines in FIG. 8 are irrelevant steps regarding the reception processing in the main unit 10.

  If the transmission unit is the own unit at the time of occurrence of this reception error, the calculation unit 21 stores the data set that could not be normally received due to the reception error, in other words, the data set in which the transmission error occurred in S470. The processing of S150 and the transmission processing can be executed so as to retransmit the data set in which the transmission error has occurred (see FIG. 9). Thereafter, the reception process ends.

  In addition, if it is determined that the reception error is not the above type of reception error (No in S415), the arithmetic unit 21 executes processing corresponding to the type of the reception error that has occurred (S495). Thereafter, the reception process ends.

  Next, processing executed by the calculation unit 41 of the subunit 30 will be described. The computing unit 41 of the subunit 30 starts the communication control process PR4 shown in FIG. 10 in response to an interrupt generated from the edge detection circuit 47 by the input of the pseudo crank angle signal.

  When the communication control process PR4 is started, the calculation unit 41 calculates the input interval of the pseudo crank angle signal as the inter-crank time (S610). Specifically, the time difference between the input start time of the current pseudo crank angle signal and the input start time of the previous pseudo crank angle signal is calculated.

  Thereafter, the calculation unit 41 sets an interrupt mask for the pseudo crank angle signal in the edge detection circuit 47 (S620), so that no interruption is generated from the edge detection circuit 47 during the interruption mask. This prevents the communication control process from being executed again.

  In addition, the calculation unit 41 determines the time until the interrupt mask is canceled based on the inter-crank time calculated in S610, in other words, determines the duration of the interrupt mask, and the interrupt mask set in S620 is A timer for canceling the interrupt mask is set for the edge detection circuit 47 so as to be canceled after the determined time has elapsed (S625). When such a setting is made, the edge detection circuit 47 cancels the interrupt mask after the elapse of the time.

  In S625, the interrupt mask duration can be set to a predetermined percentage of the inter-crank time. For example, the interruption mask duration can be set to 0.7 times or 0.8 times the time between cranks. Regarding the above ratio, in consideration of the assumed fluctuations in engine rotation, etc., the range in which the next crank interval will not be shorter than the interrupt mask duration, or the range in which the probability of shortening will be sufficiently small. , Greater than 0 and less than 1 can be determined in the design stage.

  Further, the calculation unit 41 corrects the crank angle calculated in the crank angle update process PR3 in order to suppress the crank angle error due to the transmission delay (S630). Specifically, the time lag (delay time) from the input of the crank angle signal in the main unit 10 to the input of the pseudo crank angle signal in the subunit 30 is specified from the system characteristics, and the crank angle error is determined based on this time lag. The crank angle can be corrected in the direction to erase.

  When this processing is finished, the calculation unit 41 refers to the setting value of the transmission unit to determine whether or not the transmission unit is its own unit (S640), and determines that the transmission unit is not its own unit. Then (No in S640), the communication control process is terminated, and when it is determined that the transmitting unit is the own unit (Yes in S640), the inter-crank time calculated in S610, specifically, from the inter-crank time to S625. Based on the determined interrupt mask duration, a control data group (transmission target data group) to be transmitted to the main unit 10 is determined so that data transmission is completed while the interrupt mask continues (S650). Specifically, the number and type of control data to be transmitted to the main unit 10 are determined. As the determination method here, the same method as S150 in the main unit 10 can be adopted.

  Thereafter, the calculation unit 41 sets the transmission permission flag of the own unit to ON to permit data transmission by the transmission process (S660), and ends the communication control process PR4. In the subunit 30, the same timed processing (see FIG. 5) and transmission processing (FIG. 6) as those in the main unit 10 are executed. Therefore, by this setting, the number of units determined in S650 and Various types of control data are transmitted to the main unit 10 via the transmission / reception circuit 42.

  Here, a supplementary description will be given of the scheduled processing and transmission processing executed by the calculation unit 41 of the subunit 30. In the scheduled processing and transmission processing executed by the arithmetic unit 41 of the subunit 30, the transmission / reception circuit provided in the microcomputer 40 is replaced by the transmission / reception circuit 22, the DMAC 23, the RAM 25, the ROM 26 and the edge detection circuit 27 provided in the microcomputer 20 as a matter of course. 42, DMAC 43, RAM 45, ROM 46 and edge detection circuit 47 are used. Data transmission is performed to the main unit 10.

  In addition, in the scheduled processing, before setting the transmission unit to the main unit 10 in S250, processing for setting an interrupt mask for the pseudo crank angle signal is performed (S240: FIG. 5). Here, when the interrupt mask release setting has been made, disabling the interrupt mask allows the interrupt mask to be continuously performed until the pseudo crank angle signal is generated, and the communication control processing is performed during the stall. This is not executed by the unit 41. As a result, during the stall, data communication can be normally performed between the main unit 10 and the subunit 30.

  In addition, the arithmetic unit 41 of the subunit 30 is connected to the main unit 10 in response to a reception interrupt that occurs when a series of data reception by the transmission / reception circuit 42 is completed or a reception error interrupt caused by a reception error detected by the transmission / reception circuit 42. Similarly, the reception process shown in FIG. 8 is executed. However, in this reception process, the calculation unit 41 of the subunit 30 ends the reception process after executing the process of S480 to S490 after the process of S470 (see FIG. 8).

  Specifically, in S480, the interrupt mask for the pseudo crank angle signal is canceled, and in S490, the time difference between the input start time of the current pseudo crank angle signal and the input start time of the previous pseudo crank angle signal is determined as the inter-crank time. Is calculated. The input start time of the pseudo crank angle signal input this time can be specified from the bit sequence of the received data and the signal edge detection time information stored in the edge detection circuit 47. For example, a signal edge from the active level (Lo) to the inactive level (Hi) of the pseudo crank angle signal is detected through the edge detection circuit 47, and the time 10 bits before this signal edge detection time is determined as the current pseudo crank angle. It can be specified as the input start time of the angle signal. In such a case, a process of updating the crank angle stored and held by the own unit is performed in S490.

  Although the vehicle control system 1 of the first embodiment has been described above, according to the present embodiment, the pseudo signal of the crank angle signal is transmitted from the main unit 10 to the subunit 30 through the communication line LN. Crank angle information was provided to 30. Therefore, even if the input circuit 11 for shaping the waveform of the output signal of the crank angle sensor SN is not provided in the subunit 30, the subunit 30 can hold the crank angle information and control the internal combustion engine. According to the change of the crank angle, the main unit 10 and the subunit 30 can be appropriately executed.

  According to the present embodiment, the input circuit 11 need not be provided in the subunit 30, and a signal line dedicated to pseudo crank angle signal transmission needs to be separately provided between the main unit 10 and the subunit 30. Therefore, the control of the internal combustion engine by the cooperation of the plurality of vehicle control devices (the main unit 10 and the subunit 30) can be executed with high accuracy with a simple hardware configuration.

  Further, according to the present embodiment, the pseudo crank angle signal is output to the communication line by switching the signal level of the communication line LN to the active level, and in the subunit 30, the signal level on the communication line LN becomes the active level. When a changing event occurs, an interrupt is generated by detecting the input of a pseudo crank angle signal. Accordingly, the time lag from the time when the crank angle signal is input in the main unit 10 can be suppressed, and the crank angle can be appropriately updated in the subunit 30, and the subunit 30 has highly accurate information on the crank angle. be able to.

  In addition, since this method is employed, in this embodiment, every time an interrupt is generated by the input of the pseudo crank angle signal, an interrupt mask for the pseudo crank angle signal is set for a predetermined time based on the inter-crank time. Thus, the false detection of the pseudo crank angle signal caused by the communication signal by the edge detection circuit 47 is invalidated to the calculation unit 41, and data communication is performed during this interrupt mask. Therefore, according to the present embodiment, even if the above method is adopted, it is possible to suppress the inconvenience that the communication signal is erroneously detected as a pseudo crank angle signal and erroneous processing is executed by the calculation unit 41.

  In addition, according to the present embodiment, even if a pseudo crank angle signal is generated during an interrupt mask (during data communication) due to a sudden change in engine rotation, a pseudo-crank angle signal can be detected as an error in the transmission / reception circuit. The crank angle signal is set to a signal that is active for a period that cannot be generated by a communication signal. Therefore, according to the present embodiment, it is possible to prevent improper reception data from being taken in due to generation of a pseudo crank angle signal during data communication, and to appropriately transmit data between the main unit 10 and the subunit 30. Can communicate.

  In addition, according to the present embodiment, since communication conflict between the main unit 10 and the subunit 30 is prevented by transmission / reception of transmission authority data, the main unit 10 can be operated without using full-duplex communication. The two-way communication can be appropriately performed between the unit 10 and the subunit 30, and the internal combustion engine can be controlled with high accuracy.

Therefore, it can be said that the vehicle control system 1 of the present embodiment is a very excellent system when the control of the internal combustion engine is executed in cooperation by a plurality of vehicle control devices.
The correspondence between terms is as follows. That is, the main unit 10 of the present embodiment corresponds to an example of a first vehicle control device, the input circuit 11 corresponds to an example of a crank angle signal input unit, and the pseudo crank angle signal generation circuit 15 includes a pseudo signal. The process related to data communication executed by the microcomputer 20 corresponds to an example of output means, and corresponds to an example of processing realized by the first data communication means.

  In addition, the subunit 30 corresponds to an example of a second vehicle control device, and the edge detection circuit 47 included in the microcomputer 40 corresponds to an example of a pseudo signal input detection unit, and is executed by the arithmetic unit 41 included in the microcomputer 40. The crank angle update process PR3 to be performed corresponds to an example of a process realized by the crank angle specifying means, and a process related to data communication executed by the microcomputer 40 is an example of a process realized by the second data communication means. Corresponding to

[Second Example]
Next, the vehicle control system 1 according to the second embodiment will be described. However, the vehicle control system 1 of the second embodiment has the same configuration and operation in many parts as the vehicle control system 1 of the first embodiment. Therefore, in the following, as a description of the vehicle control system 1 of the second embodiment, a hardware configuration and operation different from the first embodiment will be described, and a description of the configuration and operation common to the first embodiment will be omitted as appropriate.

  The vehicle control system 1 according to the second embodiment performs a data communication after performing a process similar to a handshake between the main unit 10 and the subunit 30 with the input of the crank angle signal, thereby improving reliability. At the same time as realizing high communication, by transmitting each type of control data according to a predetermined schedule, it is not necessary to transmit an identifier as in the first embodiment, and the control data can be efficiently transmitted while suppressing the communication amount. Transmission / reception can be realized between the main unit 10 and the subunit 30.

  As shown in FIG. 11, according to the present embodiment, as in the first embodiment, the pseudo crank angle signal generation circuit 15 of the main unit 10 generates a pseudo crank angle signal (see FIG. 1 and FIG. 11 "Pcr") is output to the communication line LN. However, the pseudo crank angle signal of this embodiment is sufficient as long as the signal can be detected by the edge detection circuit 47, and it is necessary to output it as a 10-bit signal as in the first embodiment. Absent. For example, the pseudo crank angle signal of this embodiment is output to the communication line LN as a pulse signal that sets the signal level of the communication line LN to the active level for a short time such as one bit.

  Further, when an interrupt is generated from the edge detection circuit 47 by the input of the pseudo crank angle signal, the subunit 30 sets an interrupt mask for the pseudo crank angle signal by the communication control process executed by the calculation unit 41, while the transmission / reception circuit 47. Are set to the communication ready state (waiting for data transmission / reception), and then the communication ready signal for setting the signal level of the communication line LN to the active level for a predetermined time (FIGS. 1 and 11). The “Ret” shown in FIG. 4 is output from the output port 49 to the communication line LN. This notifies the main unit 10 of completion of communication preparation. When setting the interrupt mask, the interrupt mask duration until the interrupt mask is canceled is determined based on the inter-crank time as in the first embodiment.

  The calculation unit 21 of the main unit 10 detects the input of the communication preparation completion signal through the edge detection circuit 27. In this embodiment, for example, an input capture having two or more input channels is used as the edge detection circuit 27, and as shown by a broken line in FIG. 1, a communication line LN is connected to one input channel of the edge detection circuit 27, A signal edge of a communication preparation completion signal can be detected. Further, the input circuit 11 is connected to another input channel of the edge detection circuit 27 so that the signal edge of the crank angle signal can be detected.

  Then, when the arithmetic unit 21 of the main unit 10 detects the input of the communication preparation completion signal, it determines that the subunit 30 is in the communication preparation completion state, and from this point of time, the interrupt masking by the subunit 30 is continued. Then, the control data is transmitted to the subunit 30 through the transmission / reception circuit 22. In this embodiment, by transmitting the control data in this way, the possibility of failure in receiving the control data in the subunit 30 is suppressed, and the communication reliability is improved. That is, inconvenience due to transmission of control data in a state in which the subunit 30 is not ready for reception is suppressed. However, the control data is transmitted only when the unit is to transmit data according to the schedule. Further, the arithmetic unit 21 of the main unit 10 takes in the control data received by the transmission / reception circuit 22 during the interruption mask.

  Similarly, the arithmetic unit 41 of the subunit 30 takes in the control data received by the transmission / reception circuit 42 while the interrupt mask is continuing after outputting the communication preparation completion signal from the output port 49. On the other hand, when the own unit is to transmit data according to the schedule, control data is transmitted through the transmission / reception circuit 42.

  In this embodiment, data communication and pseudo crank angle signal transmission are performed in this way. However, in this embodiment, by setting the interrupt mask duration to be shorter than the time between cranks, a pseudo crank angle signal is generated while the interrupt mask is continued as in the first embodiment. Avoid occurrence. In an environment where such a phenomenon does not occur, as described above, data communication between the main unit 10 and the subunit 30 is performed according to a predetermined schedule for each input of the crank angle signal and the pseudo crank angle signal. To do. FIG. 12 shows the configuration of schedule data for each engine speed that both the main unit 10 and the subunit 30 store in the ROMs 26 and 46.

  According to the example shown in FIG. 12, the main unit 10 and the subunit 30 have schedule data in which a communication schedule is defined when the engine speed is 1000 rpm or less, and a communication schedule when the engine speed is 1000 rpm to 2000 rpm. Schedule data in which the engine speed is 2000 rpm to 3000 rpm, schedule data in which the communication schedule is defined, etc., and schedule data in units of 1000 rpm within the range of engine speeds that the internal combustion engine can take. .

  The schedule data for each engine speed is the data type to be transmitted when the crank angle signal corresponding to the crank angle signal is input and the order of transmission, the number of data, the data The transmission direction is defined. According to the schedule data shown in FIG. 12, the type of data to be transmitted is described in the order of transmission. Further, the transmission direction “M → S” shown in FIG. 12 defines that data is transmitted from the main unit 10 to the subunit 30, in other words, that the main unit 10 is a transmission unit having data transmission authority. The transmission direction “M ← S” shown in FIG. 12 is information defining that transmission from the subunit 30 to the main unit 10, in other words, that the subunit 30 is a transmission unit having data transmission authority. As described above, in the second embodiment, unlike the first embodiment, control data to be transmitted is determined in units of the angle at which the crank angle signal is generated, and this information is shared between the main unit 10 and the subunit 30. Thus, the receiving side can determine the type of control data without an identifier.

  Next, details of the processing operation of the main unit 10 will be described using a flowchart. The calculation unit 21 of the main unit 10 executes the communication control process shown in FIG. 13 in response to an interrupt generated from the edge detection circuit 27 by the input of the crank angle signal. When this communication control process is started, the calculation unit 21 calculates the crank angle signal input interval as the inter-crank time as in the first embodiment (S710), and then determines the engine speed determined from the inter-crank time. It is determined whether or not the transmission unit is the own unit by referring to the data transmission direction information corresponding to the current crank angle in the schedule data corresponding to (S720).

  If it is determined that the transmission unit is the own unit (Yes in S720), a group of control data at the current crank angle defined to be transmitted by the schedule data is determined as a transmission target data group (S730). . Thereafter, by setting the transmission permission flag of the own unit to ON, data transmission by the transmission process shown in FIG. 15 is permitted (S740), and the communication control process is ended. On the other hand, if it is determined that the transmission unit is not its own unit (No in S720), S730 and S740 are skipped, and the communication control process is terminated.

  Further, the arithmetic unit 21 of the main unit 10 periodically executes the regular processing shown in FIG. 14 as in the first embodiment, but if it is determined that the engine is not stalled in S220, the subunit 30 communicates. It is determined whether or not it is in a ready state (S225), and only when the subunit 30 is in a communication ready state (Yes in S225), the processing after S280 is executed, and if it is not in a ready state for communication. When it is determined (No in S225), the scheduled process is terminated. By such processing, the arithmetic unit 21 prevents data transmission to the subunit 30 when the subunit 30 is not ready for communication.

  Specifically, the calculation unit 21 of the main unit 10 outputs the pseudo crank angle signal accompanying the input of the crank angle signal to the communication line LN in S225, and then from the subunit 30 via the communication line LN within a predetermined time. It is determined whether a communication preparation completion signal is input. Thereby, it is determined whether or not the subunit 30 is in a communication ready state. Whether or not a communication preparation completion signal has been input is determined by whether the edge detection circuit 27 detects a signal edge from the inactive level (Lo) to the active level (Hi) for the communication line LN within the predetermined time. Judgment can be made based on whether or not.

  The calculation unit 21 of the main unit 10 in the present embodiment performs the same processing as in the first embodiment with respect to the steps denoted by the same numbers as those in the first embodiment in FIG. In the embodiment, the schedule data defining the communication schedule at the time of the stall is stored in the ROMs 26 and 46. Therefore, the processing of S250 as in the first embodiment is not executed, and is transmitted in S260 according to this schedule data. Determine whether the unit is its own unit. In S270, a transmission target data group is determined according to the schedule data defining the communication schedule at the time of the stall.

  In S280, the transmission process shown in FIG. 15 is executed. When the transmission process shown in FIG. 15 is started, the calculation unit 21 determines whether or not the transmission permission flag of its own unit is set to ON (S810), and determines that the transmission permission flag is set to OFF. Then (No in S810), the transmission process is terminated without performing any process for data transmission by ending the transmission process without executing the processes of S820 to S850.

  On the other hand, if it is determined that the transmission permission flag is set to ON (Yes in S810), the control data group determined as the transmission target data in S730 or S270 is stored in the RAM 25 by repeatedly executing the processes in S820 and S830. Write in the transmission memory area in the order of transmission. However, in this embodiment, no identifier is used. That is, in S830, the control data is written in the transmission memory area without writing the identifier.

  When all the control data is written in the transmission memory area of the RAM 25 (Yes in S820), the calculation unit 21 inputs the transfer command to the DMAC 23 (S850), and is written in the transmission memory area in the DMAC 23. The group of control data is transferred to the transmission buffer of the transmission / reception circuit 22 so that the group of control data is sequentially transmitted to the subunit 30 from the transmission / reception circuit 22.

  In addition, the calculation unit 21 according to the present embodiment performs the reception process illustrated in FIG. 16 in response to a reception interrupt or a reception error interrupt that occurs when a series of data reception by data communication performed while the interrupt mask is continued. Run. In this reception process, it is determined whether or not a reception error has occurred in the transmission / reception circuit 22 (S910). If it is determined that no reception error has occurred (No in S910), the process of S920 is executed. Then, the reception process ends.

  Specifically, in S920, the control data stored as reception data in the reception memory area of the RAM 25 is read from the reception memory area in the order of reception, and the type of the read control data is set to the engine corresponding to the current inter-crank time. The control data is determined by referring to the portion corresponding to the current crank angle in the rotational speed schedule data, and this control data is provided to a control task related to fuel injection control that requires this control data. Thereby, the control data received by the transmission / reception circuit 22 is captured.

  On the other hand, if it is determined that the reception error has occurred (Yes in S910), processing corresponding to the type of the reception error that has occurred is executed (S930). Thereafter, the reception process ends.

  Next, details of the processing operation of the subunit 30 will be described using a flowchart. The calculation unit 41 of the subunit 30 starts the communication control process shown in FIG. 17 in response to an interrupt generated from the edge detection circuit 47 by the input of the pseudo crank angle signal.

  When the communication control process is started, the calculation unit 41 calculates the inter-crank time based on the pseudo crank angle signal as in the first embodiment (S1010). Thereafter, the calculation unit 41 sets an interrupt mask for the pseudo crank angle signal in the edge detection circuit 47 (S1020), and continues the interrupt mask as in the first embodiment based on the time between cranks calculated in S1010. The time is determined, and the interrupt mask cancellation timer is set to the edge detection circuit 47 so that the interrupt mask set in S1020 is canceled after the determined time has elapsed (S1025). Further, the calculation unit 41 corrects the crank angle (S1030).

  Thereafter, the calculation unit 41 performs various settings (operation parameter settings, etc.) on the transmission / reception circuit 47, etc., thereby bringing the unit into a communication ready state (waiting for data transmission / reception), and then completing the communication preparation described above. A signal is output from the output port 49 to the communication line LN (S1040). Further, by referring to the data transmission direction information corresponding to the current crank angle in the schedule data corresponding to the engine speed specified from the inter-crank time calculated in S1010, it is determined whether or not the transmission unit is the own unit. Judgment is made (S1050).

  If it is determined that the transmission unit is the own unit (Yes in S1050), a group of control data at the current crank angle defined to be transmitted by the schedule data is determined as a transmission target data group (S1060). Then, the transmission permission flag of the own unit is set to ON (S1070), and the communication control process ends. On the other hand, if it is determined that the transmitting unit is not its own unit (No in S1050), S1060 and S1070 are skipped, and the communication control process is terminated.

  In addition, the calculation unit 41 of the subunit 30 executes the same scheduled processing, transmission processing, and reception processing as those of the main unit 10. Of course, the transmission / reception circuit provided in the microcomputer 40 in place of the transmission / reception circuit 22, the DMAC 23, the RAM 25, the ROM 26 and the edge detection circuit 27 provided in the microcomputer 20 in the scheduled process, transmission process and reception process executed by the arithmetic unit 41 of the subunit 30. 42, DMAC 43, RAM 45, ROM 46 and edge detection circuit 47 are used. Data transmission is performed to the main unit 10.

  In addition, in S225 (see FIG. 14), whether or not the subunit 30 is in a communication ready state is determined by outputting a communication preparation completion signal from the own unit via the communication line LN by the processing in S1040 (see FIG. 17). It can be realized by determining whether or not it has been done.

  As described above, the vehicle control system 1 according to the second embodiment has been described. However, according to this embodiment, since the processing similar to the handshake is performed as described above, highly reliable communication can be efficiently realized. . The correspondence between terms is as follows. The schedule data for each engine speed stored in the ROMs 26 and 46 corresponds to an example of a table stored by the storage unit for each engine speed. The communication preparation completion signal corresponds to an example of a response signal output from the second data communication unit.

[Others]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can take various forms. For example, data communication between the main unit 10 and the subunit 30 may be realized by differential communication. In addition to the start-stop synchronization method, the data communication may employ a clock synchronization method. However, in the case of the clock synchronous type, it is necessary to provide a clock signal line for transmitting a clock signal along with the communication line LN. In addition, SPI (Serial Peripheral Interface) or the like can be used for data communication. For the transmission / reception circuits 22 and 42, a general-purpose UART (Universal Asynchronous Receiver Transmitter) or the like can be used.

Further, data communication based on schedule data in the second embodiment (in other words, data communication not using an identifier) may be applied to the first embodiment, and data communication using an identifier in the first embodiment is It may be applied to the second embodiment.
In addition, in the above-described embodiment, a fuel injection controller common to all cylinders is provided as the subunit 30, and fuel injection control is realized by the cooperation of the single main unit 10 and the single subunit 30. However, as another example, the vehicle control system 1 may be configured to include a fuel injection controller for each cylinder as the subunit 30, as shown in FIG.

DESCRIPTION OF SYMBOLS 1 ... Vehicle control system, 3 ... Injector, 10 ... Main unit, 11 ... Input circuit, 15 ... Pseudo crank angle signal generation circuit, 20, 40 ... Microcomputer, 21, 41 ... Calculation part, 22, 42 ... Transmission / reception circuit, 23 , 43 ... DMAC, 25, 45 ... RAM, 26, 46 ... ROM, 27, 47 ... edge detection circuit, 30 ... subunit, 49 ... output port, 50 ... drive circuit, LN ... communication line, SN ... crank angle sensor

Claims (12)

A vehicle control system comprising a plurality of vehicle control devices connected to a common communication line, and realizing control of an internal combustion engine mounted on the vehicle by cooperation of the plurality of vehicle control devices with data transmission / reception. ,
A first vehicle control device that is one of the plurality of vehicle control devices,
Crank angle signal input means for inputting a crank angle signal as a pulse signal in accordance with a change in crank angle in the internal combustion engine;
For each input of the crank angle signal by the crank angle signal input means, Ri pseudo signal der of the crank angle signal, a pseudo crank angle signal Ru pulse signal der having an effective edge synchronized with an edge of the crank angle signal Pseudo signal output means for outputting to the communication line;
A means for transmitting the data via the communication line to a second vehicle control device different from the first vehicle control device among the plurality of vehicle control devices, wherein the input interval of the crank angle signal And the first data communication means for transmitting the data during a period in which the pseudo crank angle signal is estimated not to be output to the communication line after the output of the pseudo crank angle signal to the communication line is stopped.
With
The second vehicle control device is
Pseudo signal input detection means for detecting the input of the pseudo crank angle signal input via the communication line;
Crank angle specifying means for specifying the crank angle of the internal combustion engine based on the detection result by the pseudo signal input detection means;
Second data communication means for receiving the data transmitted from the first vehicle control device via the communication line;
A vehicle control system comprising:   A vehicle control system comprising a plurality of vehicle control devices connected to a common communication line, and realizing control of an internal combustion engine mounted on the vehicle by cooperation of the plurality of vehicle control devices with data transmission / reception. ,
  A first vehicle control device that is one of the plurality of vehicle control devices,
  Crank angle signal input means for inputting a crank angle signal as a pulse signal in accordance with a change in crank angle in the internal combustion engine;
  Pseudo signal output means for outputting a pseudo crank angle signal, which is a pseudo signal of the crank angle signal, to the communication line every time the crank angle signal is input by the crank angle signal input means;
  A means for transmitting the data via the communication line to a second vehicle control device different from the first vehicle control device among the plurality of vehicle control devices, wherein the input interval of the crank angle signal And the first data communication means for transmitting the data during a period in which the pseudo crank angle signal is estimated not to be output to the communication line after the output of the pseudo crank angle signal to the communication line is stopped.
  With
  The second vehicle control device is
  Pseudo signal input detection means for detecting the input of the pseudo crank angle signal input via the communication line;
  Crank angle specifying means for specifying the crank angle of the internal combustion engine based on the detection result by the pseudo signal input detection means;
  Second data communication means for receiving the data transmitted from the first vehicle control device via the communication line;
  With
  Asynchronous communication is performed between the first data communication unit and the second data communication unit, and thereby, when transmitting the data, a fixed-length bit string that is the data for one unit. A communication signal including a start bit and a stop bit before and after is output to the communication line,
  The pseudo signal output means, for each input of the crank angle signal, by switching the signal level of the communication line to an active level for a certain time equal to or longer than the time length of the communication signal from the start bit to the stop bit, Outputting the pseudo crank angle signal, which is distinguished from the communication signal, to the communication line;
  A vehicle control system. A vehicle control system comprising a plurality of vehicle control devices connected to a common communication line, and realizing control of an internal combustion engine mounted on the vehicle by cooperation of the plurality of vehicle control devices with data transmission / reception. ,
A first vehicle control device that is one of the plurality of vehicle control devices,
Crank angle signal input means for inputting a crank angle signal as a pulse signal in accordance with a change in crank angle in the internal combustion engine;
Pseudo signal output means for outputting a pseudo crank angle signal, which is a pseudo signal of the crank angle signal, to the communication line every time the crank angle signal is input by the crank angle signal input means;
A means for transmitting the data via the communication line to a second vehicle control device different from the first vehicle control device among the plurality of vehicle control devices, wherein the input interval of the crank angle signal And the first data communication means for transmitting the data during a period in which the pseudo crank angle signal is estimated not to be output to the communication line after the output of the pseudo crank angle signal to the communication line is stopped.
With
The second vehicle control device is
Pseudo signal input detection means for detecting the input of the pseudo crank angle signal input via the communication line;
Crank angle specifying means for specifying the crank angle of the internal combustion engine based on the detection result by the pseudo signal input detection means;
Second data communication means for receiving the data transmitted from the first vehicle control device via the communication line;
With
The pseudo signal output means outputs the pseudo crank angle signal to the communication line by switching the signal level of the communication line to an active level for a predetermined time every time the crank angle signal is input.
The second data communication means outputs a response signal to the first vehicle control device via the communication line when the pseudo crank angle signal input is detected by the pseudo signal input detection means. , Start the data reception waiting operation,
The first data communication means transmits the data to the second vehicle control device only during a period in which the pseudo crank angle signal is estimated not to be output to the communication line after the response signal is input. Run
The pseudo signal input detection means detects an input of the pseudo crank angle signal at the time when an event occurs in which the signal level on the communication line changes to an active level, and thereafter, the pseudo crank angle signal is transmitted to the communication line. The vehicle control system is characterized in that the operation of detecting the input of the pseudo crank angle signal is disabled until the end of the period estimated not to be output to the line . The second data communication means, after stopping the output of the pseudo crank angle signal to the communication line, based on the input interval of the pseudo crank angle signal specified from the detection result of the pseudo signal input detection means, In a period during which it is estimated that an angular signal is not output to the communication line, the data is transmitted to the first vehicle control device via the communication line.
Said first data communication means, one of the claims 1 to 3, characterized in that it is in the configuration for receiving said data transmitted from said second vehicle control apparatus via said communication line the vehicle control system of one claim or. The first and second data communication means are periods during which it is estimated that the pseudo crank angle signal is not output to the communication line after the output of the pseudo crank angle signal to the communication line is stopped. The vehicle control system according to claim 4 , wherein the data is transmitted during a period in which the data transmission authority exists. The first and second data communication means, when the own device has the transmission authority, as one of the data, the transmission authority data describing the identification code of the vehicle control device to which the next transmission authority is given The pseudo crank angle after stopping the output of the pseudo crank angle signal generated after the reception when receiving the transmission authority data in which the identification code of the own device is written via the communication line The vehicle control system according to claim 5 , wherein a period in which a signal is estimated not to be output to the communication line is determined as a period in which the device has an authority to transmit the data. The operation of transmitting the data during a period during which it is estimated that the pseudo crank angle signal is not output to the communication line is the number of data that can be transmitted during the period during which the pseudo crank angle signal is not output to the communication line. The number of data to be transmitted is determined within the range, and the output of the pseudo crank angle signal to the communication line is stopped, and then the determined number of the data is transmitted. The vehicle control system according to any one of claims 1 to 6 . The first vehicle control device has storage means for storing a table in which the type and number of data to be transmitted for each input of the crank angle signal are defined for each rotation speed of the internal combustion engine,
For each input of the crank angle signal, the first data communication means refers to the table of the rotational speed of the internal combustion engine corresponding to the input interval of the crank angle signal, and the pseudo crank angle signal for the communication line After the output is stopped, it is estimated that the pseudo crank angle signal is not output to the communication line by transmitting the type and number of data according to the table to the second vehicle control device via the communication line. The vehicle control system according to any one of claims 1 to 3 , wherein the data is transmitted to the second vehicle control device via the communication line during a period of time. Each of the first and second vehicle control devices stores a table in which the type, number, and source of data to be transmitted for each input of the crank angle signal are defined for each rotation speed of the internal combustion engine. Having means,
For each input of the crank angle signal, the first data communication means refers to the table of the rotational speed of the internal combustion engine corresponding to the input interval of the crank angle signal, and the pseudo crank angle signal for the communication line When the transmission source according to the table is its own device after the output stops, the type and number of data according to the table are transmitted to the second vehicle control device via the communication line, thereby In a period during which it is estimated that a pseudo crank angle signal is not output to the communication line, the data is transmitted to the second vehicle control device via the communication line,
The second data communication means corresponds to the input interval of the pseudo crank angle signal every time the pseudo signal input detection means detects the input of the pseudo crank angle signal due to the input of the crank angle signal. After referring to the table of the rotational speed of the internal combustion engine and stopping the output of the pseudo crank angle signal, if the transmission source according to the table is its own device, the data of the type and number according to the table are By transmitting to the first vehicle control device via the communication line, the first vehicle control device via the communication line during a period during which it is estimated that the pseudo crank angle signal is not output to the communication line. The vehicle control system according to claim 4 , wherein the data is transmitted to the vehicle. The pseudo signal output means is configured to output the pseudo crank angle signal to the communication line by switching the signal level of the communication line to an active level.
The pseudo signal input detection means detects an input of the pseudo crank angle signal at the time when an event occurs in which the signal level on the communication line changes to an active level, and at the same time, before the trigger of the detection From the time of occurrence of the event until the end of the period during which it is estimated that the pseudo crank angle signal after the stop of the output of the pseudo crank angle signal to the communication line is not output to the communication line, the pseudo crank angle signal 3. The vehicle control according to claim 1, wherein an input of the pseudo crank angle signal is detected every time the pseudo crank angle signal is input by disabling an operation of detecting an input. 4. system. Asynchronous communication is performed between the first data communication unit and the second data communication unit, and thereby, when transmitting the data, a fixed-length bit string that is the data for one unit. A communication signal including a start bit and a stop bit before and after is output to the communication line,
The pseudo signal output means, for each input of the crank angle signal, by switching the signal level of the communication line to an active level for a certain time equal to or longer than the time length of the communication signal from the start bit to the stop bit, claim 1 or claim 3 vehicle control system according and outputs the pseudo crank angle signal that is distinct from that of the communication signal to the communication line. The second data communication means outputs a response signal to the first vehicle control device via the communication line when the pseudo crank angle signal input is detected by the pseudo signal input detection means. , Start the data reception waiting operation,
The said 1st data communication means performs the transmission operation | movement of the said data with respect to a said 2nd vehicle control apparatus after the input of the said response signal. The Claim 1 , Claim 2, or Claim 10 characterized by the above-mentioned. Vehicle control system.

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