JP2013104358A - Vehicle control system and vehicle control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow an input circuit for inputting signals from a crank angle sensor not necessarily to be installed in each electronic control device which executes processings concerned with engine control.SOLUTION: The system to accomplish an engine control through cooperation of a plurality of electronic control devices involving communications, includes a main electronic control device which is furnished with an input circuit for crank signals, and sub-electronic control device(s) each furnished as substitute for such an input circuit, with a circuit producing a communication crank signal as a pseudo signal of the crank signal on the basis of a special differential signal transmitted from the main electronic control device via a communication line. Each time the crank signal becomes active, the main electronic control device inputs the special differential signal to the communication line. The sub-electronic control device(s) produces the communication crank signal whose signal level changes between high and low complying with the input pattern of the special differential signal, and based on the given signal, executes a processing (NE synchronize processing) concerned with the engine control complying with the change of the crank angle.

Description

  The present invention relates to a system and an apparatus for controlling an internal combustion engine mounted on a vehicle.

  2. Description of the Related Art Conventionally, as a system for controlling an internal combustion engine, a technique for detecting 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). There is also known a system in which an injector installed in each cylinder and an electronic control unit that performs fuel injection control are communicably connected (see Patent Document 2).

JP 2008-144749 JP 2010-144692 A

  By the way, in the system and the like for detecting the pressure fluctuation mode, an electronic control unit for fuel injection control is provided separately from the main electronic control unit for controlling the internal combustion engine in order to perform optimum fuel injection control based on the pressure fluctuation mode. It is conceivable to control the internal combustion engine by cooperation of the plurality of electronic control devices by providing the electronic control device for each injector.

  When the internal combustion engine is controlled by such a plurality of electronic control units, each electronic control unit is provided with a crank angle sensor in order to appropriately perform the process related to the control of the internal combustion engine according to the change in the crank angle. It is conceivable that a signal output from the crank angle sensor according to a change in the crank angle is input to each electronic control unit.

  However, when a crank angle sensor is connected to each electronic control unit, it is necessary to provide an input circuit for inputting an output signal of the crank angle sensor to each of the electronic control units. The output signal of the crank angle sensor takes a different waveform such as a sine wave or a rectangular wave depending on the type of sensor. For this reason, the output signal from the crank angle sensor needs to be shaped into a specified waveform signal by the input circuit, and the shaped signal needs to be input into the apparatus.

  The present invention has been made in view of such problems, and each control device can perform processing related to control of an internal combustion engine without providing an input circuit for inputting an output signal of a crank angle sensor in each control device. The aim is to provide a technology that can be implemented appropriately.

  A first invention made to achieve the above object (Claim 1) includes a plurality of vehicle control devices connected to a communication line for differential communication, and controls an internal combustion engine mounted on the vehicle. A vehicle control system realized by cooperation of a plurality of vehicle control devices with communication, wherein a first vehicle control device that is one of the plurality of vehicle control devices is different from the first vehicle control device. The second vehicle control device is configured as follows.

  The first vehicle control device includes crank signal input means and transmission control means. The crank signal input means is a means for inputting, to the transmission control means, a crank signal whose signal level changes between an active level and an inactive level in accordance with a change in crank angle in the internal combustion engine. For example, the crank signal input means can be configured to shape the output signal from the crank angle sensor and input it to the transmission control means. Specifically, the crank signal input means, for example, shapes the output signal from the crank angle sensor output in the form of a sine wave or a rectangular wave into a prescribed waveform signal such as a rectangular signal and transmits it. It can be configured to input to the control means.

  On the other hand, the transmission control means is means for converting data to be transmitted into a differential signal for data transmission and outputting it to the communication line. However, when the signal level of the crank signal inputted from the crank signal input means changes to the active level, the transmission control means replaces the data transmission differential signal for a predetermined period instead of the data transmission differential signal. A special differential signal which is a differential signal different from the motion signal is output to the communication line. Examples of the “predetermined period” herein include a period until the signal level of the crank signal changes to an inactive level. That is, when the signal level of the crank signal input from the crank signal input means is an inactive level, the transmission control means uses the data to be transmitted generated by the processing related to the control of the internal combustion engine for data transmission. When the signal level of the crank signal input from the crank signal input means is an active level, the differential signal is different from the differential signal for data transmission. It can be configured to output a signal to a communication line.

  As is well known, in differential communication, a communication signal is represented by a combination of signals (single-ended signals) flowing through two signal lines. A signal whose information is represented by a signal flowing through a signal line. In other words, the “differential signal” referred to here means a differential signal in a broad sense that is not limited to a signal composed of a combination of signals having opposite phases.

  On the other hand, the second vehicle control device includes data reception means and pseudo signal generation means. Data receiving means is means for generating received data by restoring the data to be transmitted that has been converted to the differential signal for data transmission and output to the communication line based on an input signal from the communication line It is. On the other hand, the pseudo signal generating means is means for generating a pseudo signal of the crank signal based on the input signal from the communication line. Specifically, the pseudo signal generation means is a signal whose signal level changes between an active level and an inactive level according to the input pattern of the special differential signal, and the special differential signal is input. In this case, a signal whose signal level changes to an active level each time it is generated can be generated as a pseudo signal of the crank signal.

  The second vehicle control device performs processing related to the control of the internal combustion engine based on the received data and the pseudo signal. For example, the second vehicle control device can be configured to execute a process related to the control of the internal combustion engine based on the received data in accordance with a change in the crank angle specified from the pseudo signal. Furthermore, the second vehicle control device executes a predetermined process related to the control of the internal combustion engine every time the pseudo signal generated by the pseudo signal generating means is switched to the active level, or synchronizes with the pseudo signal. Alternatively, the processing based on the crank angle specified from the pseudo signal can be executed asynchronously with the pseudo signal.

  According to the vehicle control system of the present invention configured as described above, the first vehicle control device inputs the special differential signal to the communication line used for data transmission / reception between the vehicle control devices, A signal corresponding to the crank signal is transmitted to another vehicle control device (second vehicle control device). Therefore, according to the present invention, even if the crank signal input circuit is not provided in the second vehicle control device, the second vehicle control device can appropriately perform the processing related to the internal combustion engine according to the change in the crank angle. Processing can be executed.

  By the way, the first vehicle control device may be configured to execute the processing related to the control of the internal combustion engine based on the crank signal input from the crank signal input means. Similarly to the apparatus, the apparatus includes pseudo signal generation means for generating a pseudo signal of the crank signal based on the input signal from the communication line, and the process related to the control of the internal combustion engine is generated by the pseudo signal generation means provided in the own apparatus. It may be configured to execute based on the pseudo signal. As described above, if the first and second vehicle control devices are configured, the control of the internal combustion engine by the cooperation of the plurality of vehicle control devices can be more appropriately executed.

  Further, according to the transmission control means, when the signal level of the crank signal changes to the active level, the output operation of the special differential signal to the communication line is started. There is a possibility that the “operation of converting to a differential signal for transmission and outputting to a communication line” may be interrupted. Therefore, the transmission control means included in the first vehicle control device is configured to “data transmission” because the signal level of the crank signal is changed to the active level and the operation of outputting the special differential signal to the communication line is started. After the operation of outputting the above-mentioned special differential signal to the communication line is completed, the data for transmission is again transmitted after the operation of converting to the differential signal for output to the communication line is interrupted. It is good to make it the structure which converts into a differential signal and outputs to a communication line (Claim 3).

  In addition, the first vehicle control device includes a cam signal input means for inputting a cam signal whose signal level changes between an active level and an inactive level in accordance with a change in cam angle in the internal combustion engine, and a cam Cam state data generating means for generating, as transmission target data, cam state data indicating that the signal level of the cam signal is the active level when the signal level of the cam signal input from the signal input means is switched to the active level; It is good to provide. Further, the transmission control means included in the first vehicle control device converts the cam state data generated by the cam state data generation means into a differential signal for data transmission in preference to other data to be transmitted. It may be configured to output to the communication line (claim 4).

  If the vehicle control system is configured using the first vehicle control device having such a configuration, it is not necessary to provide an input circuit for each vehicle control device with respect to the cam signal, and the efficiency is improved by using a communication line for differential communication. Thus, the cam angle information can be transmitted to each vehicle control device.

  Further, the vehicle control system described above can be specifically configured as follows. That is, the first vehicle control device performs processing related to the control of the internal combustion engine, the transmission circuit, the microcomputer that inputs the data to be transmitted to the transmission circuit, and the active control according to the change of the crank angle in the internal combustion engine. A crank signal input circuit that inputs a crank signal whose signal level changes between the level and the inactive level to the transmission circuit can be provided.

  The transmission circuit converts the data to be transmitted input from the microcomputer into a differential signal for data transmission and outputs it to the communication line, while the signal level of the crank signal input from the crank signal input circuit is When the level changes to the active level, instead of the differential signal for data transmission for a predetermined period, the special differential signal different from the differential signal for data transmission may be output to the communication line. it can.

  Further, the second vehicle control device generates reception data that is converted into a differential signal for data transmission based on an input signal from the communication line and restores the transmission target data output to the communication line. A signal whose signal level changes between an active level and an inactive level according to the input pattern of a special differential signal based on an input signal from the data receiving circuit and the communication line, and has a special differential And a pseudo signal generation circuit that generates a pseudo signal of a crank signal whose signal level changes to an active level each time a signal is input (claim 5). Furthermore, the second vehicle control device includes a microcomputer, and the microcomputer performs processing related to the control of the internal combustion engine based on the received data and the pseudo signal generated by the pseudo signal generation circuit included in the own device. It can be configured to execute.

  Thus, according to the vehicle control system that performs the output of the special differential signal and the generation of the pseudo signal based on the special differential signal without using a microcomputer, the signal level of the crank signal is changed. The above-mentioned special differential signal can be output at high speed, and the pseudo signal with a small delay from the crank signal can be generated, and the internal combustion engine according to the change of the crank angle in each vehicle control device It is possible to more appropriately perform the process related to the control.

  However, the crank signal input circuit included in the first vehicle control device may be configured to input a crank signal to a microcomputer included in the first vehicle control device instead of the transmission circuit. The microcomputer included in the first vehicle control device converts the crank signal input from the crank signal input circuit into a crank signal whose signal level changes to an active level whenever the crank angle changes by a specified amount, The transmission circuit may be configured to output the special differential signal to the communication line based on a crank signal input from the microcomputer.

  If the vehicle control system is configured in this way, a crank signal having a different crank angle change amount corresponding to one cycle of the crank signal is input from the crank signal input circuit due to a difference in the type of the crank angle sensor or the like. Even if there is a microcomputer, this crank signal can be easily converted into a prescribed crank signal corresponding to the configuration of each vehicle control device, and the degree of freedom of the combination of the vehicle control system and the crank angle sensor. Can be increased.

  In addition, the first vehicle control device can be configured to include a pseudo signal generation circuit, similarly to the second vehicle control device, and the microcomputer included in the first vehicle control device controls the internal combustion engine. The processing according to (1) can be configured to be executed based on a pseudo signal input from a pseudo signal generation circuit included in the own device (for example, in accordance with a change in crank angle specified from the pseudo signal). 7).

  In addition, the microcomputer included in the first vehicle control device detects that the pseudo signal input from the pseudo signal generation circuit has changed to the active level, thereby transferring the special differential signal to the communication line by the transmission circuit. It can be configured to detect that the output operation is started. When the microcomputer included in the first vehicle control device detects that the output operation of the special differential signal to the communication line by the transmission circuit is started, the microcomputer transmits the special differential signal to the communication line. The transmission of the data to be transmitted, which has been interrupted by the operation of converting to the differential signal for data transmission by the transmission circuit due to the start of the output operation and outputting to the communication line, is performed by the communication of the special differential signal. After the output operation to the line is completed, the data to be transmitted can be retransmitted by inputting the data to the transmission circuit again (claim 8).

  The first vehicle control device includes a cam signal input circuit that inputs a cam signal whose signal level changes between an active level and an inactive level in accordance with a change in cam angle in the internal combustion engine. When the signal level of the cam signal input from the cam signal input circuit is switched to the active level, the microcomputer included in the vehicle control device of the vehicle control device transmits the cam status data indicating that the signal level of the cam signal is the active level. And the cam state data can be input to the transmission circuit in preference to other data to be transmitted.

  In addition, the invention of the vehicle control system described above can be applied to the invention of the vehicle control device. The second invention (Claim 10) is mounted on a vehicle in cooperation with another vehicle control device by being connected to a communication line for differential communication and communicating with the other vehicle control device through the communication line. A vehicle control device for controlling the internal combustion engine, comprising the above-mentioned crank signal input means and transmission control means, and the signal level of the crank signal with respect to other vehicle control devices by the special differential signal. A signal representing a change is transmitted. According to this vehicle control device, as with the vehicle control system described above, there is an advantage that it is not necessary to provide an input circuit for the crank signal in another vehicle control device.

1 is a block diagram illustrating a configuration of a vehicle control system 1. FIG. 2 is a block diagram (A) illustrating the configuration of a communication circuit 13 included in the main electronic control device 10 and a block diagram (B) illustrating the configuration of a communication circuit 33 included in the sub electronic control device 30. FIG. It is the figure which showed the waveform of the differential signal. FIG. 2 is a block diagram (A) showing a configuration of a transmission circuit 14 provided in the main electronic control device 10 and a block diagram (B) showing a configuration of reception circuits 15 and 35 provided in the main and sub electronic control devices 10 and 30. 4 is a flowchart showing crank signal monitoring processing executed by microcomputers 11 and 31 of main and sub electronic control units 10 and 30. 4 is a flowchart showing a vehicle control process executed by microcomputers 11 and 31 of main and sub electronic control units 10 and 30. 4 is a flowchart showing a transmission control process executed by microcomputers 11 and 31 of main and sub electronic control units 10 and 30. 3 is a flowchart showing a reception control process executed by microcomputers 11 and 31 of main and sub electronic control units 10 and 30. It is the time chart which showed the change timing of each signal and the execution timing of each processing. It is a block diagram showing the structure of the vehicle control system 1 'of a 1st modification. FIG. 6 is a block diagram (A) illustrating a configuration of a transmission circuit 40 and a block diagram (B) illustrating a configuration of a reception circuit 50 in a second modification. It is the figure which showed the waveform of the differential signal in a 2nd modification. FIG. 10 is a block diagram (A) illustrating a configuration of a transmission circuit 60 and a block diagram (B) illustrating a configuration of a reception circuit 70 in a third modification. It is the figure which showed the waveform of the differential signal in a 3rd modification.

Embodiments of the present invention will be described below with reference to the drawings.
The vehicle control system 1 of the present embodiment includes a plurality of electronic control devices 10 and 30 connected to a communication line LN for differential communication, and includes communication for controlling an engine as an internal combustion engine mounted on the vehicle. This is a system realized by cooperation of a plurality of electronic control units 10 and 30. The vehicle control system 1 includes a main electronic control device 10 as an electronic control device that performs overall control of the engine, and a plurality of other sub electronic control devices 30. An example of the sub electronic control device 30 is an electronic control device that is provided for each cylinder and that performs fuel injection control of the corresponding cylinder. When the sub electronic control unit 30 is an electronic control unit that performs such fuel injection control, each of the sub electronic control units 30 transmits the fuel injection amount and the injection transmitted from the main electronic control unit 10 through the communication line LN. Based on the timing information, the corresponding injector can be controlled. Further, the sub electronic control unit 30 can be configured to transmit the learning result of the fuel injection control and the detection result of the pressure sensor or the like to the main electronic control unit 10 through the communication line LN.

  The main electronic control unit 10 constituting the vehicle control system 1 includes a microcomputer (hereinafter referred to as “microcomputer”) 11, a communication circuit 13 connected to the communication line LN, and an output signal of the crank angle sensor 21. An input circuit 17 for inputting to the communication circuit 13 and an input circuit 19 for inputting an output signal of the cam angle sensor 23 to the microcomputer 11 are provided.

  The microcomputer 11 includes a memory 11a that stores various programs and data. The microcomputer 11 performs processing related to engine control and communication with another electronic control unit 30 via the communication circuit 13 according to the program recorded in the memory 11a. Execute the process. Specifically, the microcomputer 11 outputs an output signal (cam signal) of the cam angle sensor 23 input through the input circuit 19 and a pseudo signal of a crank signal input from the communication circuit 13 (SYNCCO: details will be described later). Based on the above, processing related to engine control is executed in accordance with engine rotation (changes in cam angle and crank angle).

  The crank angle sensor 21 is constituted by a rotary encoder attached to the crankshaft, and is a known sensor that outputs a crank signal whose signal (voltage) level changes in accordance with a change in the crank angle. The cam angle sensor 23 is a sensor that is attached to the cam shaft and outputs a cam signal whose signal level changes in accordance with a change in the cam angle, like the crank angle sensor 21.

  As the crank angle sensor 21, a sensor that outputs a sine wave or a rectangular wave as the crank signal is known. As the cam angle sensor 23, a sensor that outputs a sine wave or a rectangular wave as the cam signal is known.

  The input circuit 17 amplifies and shapes the crank signal input from the crank angle sensor 21, so that the signal (voltage) level is high (active level) and low (inactive level) according to the change of the crank angle. ), And is input to the communication circuit 13. Similarly, the input circuit 19 amplifies and shapes the cam signal input from the cam angle sensor 23, so that the signal (voltage) level is high (active level) and low (active level) according to the change of the cam angle. After being converted into a rectangular signal that changes between (inactive level), this is input to the microcomputer 11.

  On the other hand, the communication circuit 13 converts transmission data (TXD) input from the microcomputer 11 into a differential signal, and the differential signal is transmitted to the communication line LN configured by the two signal lines L1 and L2. Output. Specifically, the communication circuit 13 included in the main electronic control device 10 includes a transmission circuit 14 and a reception circuit 15 connected to the communication line LN, as shown in FIG.

  The transmission circuit 14 operates based on transmission data (TXD) input from the microcomputer 11 and a crank signal (SYNCI) input from the input circuit 17, and outputs a differential signal to the communication line LN. It is. As shown in FIGS. 1 and 2A, the transmission circuit 14 outputs the first single-end signal (COMH) constituting the differential signal to the first signal line L1 constituting the communication line LN. The second single-end signal (COML) constituting the differential signal is output to the second signal line L2 constituting the communication line LN.

  On the other hand, the reception circuit 15 generates reception data (RXD) corresponding to transmission data (TXD) output as a differential signal to the communication line LN based on the differential signal flowing through the communication line LN. The reception data (RXD) generated by the reception circuit 15 is input to the microcomputer 11 and stored in a reception buffer (not shown) provided in the microcomputer 11. Further, the reception circuit 15 has a function of generating a pseudo signal (SYNCO) of a crank signal based on a differential signal flowing through the communication line LN and inputting the pseudo signal (SYNCO) to the microcomputer 11. Hereinafter, the pseudo signal (SYNCO) of the crank signal is also expressed as a communication crank signal (SYNCO).

  Each of the sub electronic control devices 30 includes a microcomputer 31 and a communication circuit 33 as in the main electronic control device 10. However, each of the sub electronic control units 30 is different from the main electronic control unit 10 in that it does not include an input circuit for inputting output signals from the crank angle sensor 21 and the cam angle sensor 23 into the apparatus.

  The communication circuit 33 included in the sub electronic control unit 30 includes a transmission circuit 34 and a reception circuit 35 connected to the communication line LN, as shown in FIG. The transmission circuit 34 converts transmission data (TXD) input from the microcomputer 31 into a differential signal and outputs it to the communication line LN. On the other hand, the receiving circuit 35 has the same configuration as the receiving circuit 15 of the main electronic control unit 10 and generates reception data from the differential signal flowing through the communication line LN, while communicating based on the differential signal flowing through the communication line LN. A crank signal (SYNCO) is generated and input to the microcomputer 31.

  The microcomputer 31 of the sub electronic control unit 30 executes processing related to engine control and processing related to communication with other electronic control units in accordance with a program recorded in the memory 31a. In this case, the communication circuit 33 Based on the generated communication crank signal (SYNCO), processing related to engine control is executed in accordance with the change in the crank angle. Then, data generated by processing related to the engine control or the like is sequentially input to the communication circuit 33 as transmission data (TXD). On the other hand, the reception data (RXD) generated by the communication circuit 33 is stored and processed in a built-in reception buffer (not shown).

  The difference between the transmission data (TXD) by the transmission circuit 14 of the main electronic control device 10 and the transmission data (TXD) by the transmission circuit 34 of each sub electronic control device 30 is the difference between the operation of outputting the transmission data (TXD) as a differential signal to the communication line LN. Each of the operations to be output to the communication line LN as a motion signal is executed so as not to overlap each other by communication arbitration by the microcomputers 11 and 31 according to a predetermined communication protocol. As is well known, in the CAN system, which is a communication protocol for an in-vehicle network, communication arbitration is performed using a CSMA (Carrier Sense Multiple Access) / CA (Collision Avidance) system.

  Subsequently, the types of differential signals used in the vehicle control system 1 of the present embodiment and the detailed configurations of the transmission circuits 14 and 34 and the reception circuits 15 and 35 constituting the communication circuits 13 and 33 are shown in FIGS. Will be described.

  As shown in FIG. 3, in the vehicle control system 1 of the present embodiment, three different signals are transmitted as differential signals. Specifically, the signal level of the crank signal (SYNCI) input from the input circuit 17 to the communication circuit 13 is low (inactive level), and the transmission data (TXD) is transmitted from the microcomputers 11 and 31 to the communication circuit 13, When the value input to 33 is “1”, the communication line LN has a 3.5V single-ended signal (COMH) and a 1.5V single-ended signal (COML) as the first differential signal. A differential signal consisting of a combination of

  On the other hand, the signal level of the crank signal (SYNCI) input from the input circuit 17 to the communication circuit 13 is low (inactive level), and transmission data (TXD) is transmitted from the microcomputers 11 and 31 to the communication circuits 13 and 33. When the input value is “0”, the communication line LN includes a 2.5V single-ended signal (COMH) and a 2.5V single-ended signal (COML) as the second differential signal. A differential signal having a potential difference of 0 V composed of the combination is transmitted.

  When the signal level of the crank signal input from the input circuit 17 to the communication circuit 13 is high (active level), the communication line LN has a 5V single-ended signal (COMH) as a third differential signal. And a differential signal composed of a combination of 0V single-ended signal (COML) is transmitted. Note that the third differential signal is not subjected to the communication arbitration procedure, and when the signal level of the crank signal (SYNCI) becomes high (active level), the transmission circuit 14 of the main electronic control unit 10 is used. Is input to the communication line LN. At this time, the third differential signal is transmitted through the communication line LN regardless of whether or not the data transmission operation is performed by the electronic control devices 10 and 30.

  FIG. 4A shows a configuration of the transmission circuit 14 of the main electronic control unit 10 that can input such first to third differential signals to the communication line LN. As shown in FIG. 4A, the transmission circuit 14 includes inverters IV1, IV2, IV3, IV4, transistors TR1, TR2, TR3, TR4, and resistors R11, R12.

  According to this transmission circuit 14, when the crank signal (SYNCI) input from the input circuit 17 is low and the input from the microcomputer 11 is the value “1” (high), the N-type transistor TR1 is turned on, and the P-type The transistor TR2 is turned on, the N-type transistor TR3 is turned off, the P-type transistor TR4 is turned off, and the first differential signal is transmitted to the communication line LN. Further, according to the transmission circuit 14, when the crank signal (SYNCI) input from the input circuit 17 is low and the input (TXD) from the microcomputer 11 is “0”, the N-type transistor TR1 is turned off, The P-type transistor TR2 is turned off, the N-type transistor TR3 is turned off, the P-type transistor TR4 is turned off, and the second differential signal is transmitted to the communication line LN.

  When the crank signal (SYNCI) input from the input circuit 17 is high (active level), the N-type transistor TR3 is turned on, the second signal line L2 is grounded, and the P-type transistor TR4 is turned on. Thus, the power supply voltage (5 V) is applied to the first signal line L1. Thus, the third differential signal is transmitted to the communication line LN regardless of the states of the transistors TR1 and TR2. In this way, the transmission circuit 14 switches and outputs the first to third differential signals to the communication line LN. On the other hand, the transmission circuit 34 of the sub electronic control unit 30 has the same configuration as a known differential communication transmission circuit.

  In addition, the receiving circuits 15 and 35 of the main electronic control device 10 and the sub electronic control device 30 have the circuit configuration shown in FIG. Specifically, the receiving circuit 15 includes comparators CM0, CM1, and CM2, an AND circuit AG, and resistors R31, R32, and R33. When the potential of the signal line L1 is higher than that of the signal line L2, the comparator CM0 having the signal lines L1 and L2 connected to the input terminals outputs a value “1” as received data (RXD), and the potential of the signal line L1 is When the potential is equal to or lower than the potential of the signal line L2, the value “0” is output as the reception data (RXD).

  On the other hand, the signal line L1 is connected to the plus input terminal of the comparator CM1, and the 5V power source is connected to the minus input terminal of the comparator CM1 via the resistor R31. A fixed voltage (for example, 4V) greater than 3.5V and less than 5V is applied to the negative input terminal via the resistor R31. That is, the comparator CM1 constituting the receiving circuits 15 and 35 outputs the value “1” when the third differential signal is transmitted through the communication line LN, and the first and second differential signals are output. When any one of the signals is transmitted through the communication line LN, the operation is performed so as to output the value “0”.

  In addition, the signal line L2 is connected to the minus input terminal of the comparator CM2, and the 5V power source is connected to the plus input terminal of the comparator CM2 via resistors R31 and R32. A fixed voltage (for example, 1V) greater than 0V and less than 1.5V is applied to the plus input terminal via resistors R31 and R32. That is, the comparator CM2 constituting the receiving circuits 15 and 35 outputs the value “1” when the third differential signal is transmitted through the communication line LN, and the first and second differential signals are output. When any of the signals is transmitted through the communication line LN, the value “0” is output.

  The AND circuit AG outputs a value “1” based on the output signals from the comparators CM1 and CM2, and outputs the value “1” when the third differential signal is transmitted through the communication line LN. When one of the two differential signals is transmitted through the communication line LN, the value “0” is output. The output signal of the AND circuit AG corresponds to the communication crank signal (SYNCO) described above. That is, the AND circuit AG is a signal whose signal level changes between high (active level) and low (inactive level) according to the input pattern of the third differential signal, Each time the transmission signal is switched to the third differential signal, the signal level changes to high (active level), and the transmission signal on the communication line LN is a differential signal for data transmission from the third differential signal. Each time the signal is switched to the first or second differential signal, a communication crank signal (SYNCO) whose signal level changes to low (inactive level) is generated and input to the microcomputers 11 and 31 of its own apparatus.

In the present embodiment, such a configuration of the receiving circuits 15 and 35 generates a pseudo signal (communication crank signal) of the crank signal and inputs it to the microcomputers 11 and 31 of the own apparatus.
Subsequently, processing operations of the microcomputers 11 and 31 will be described. The microcomputer 11 of the main electronic control unit 10 and the microcomputer 31 of each sub electronic control unit 30 repeatedly execute the crank signal monitoring process shown in FIG. 5 to perform processing according to the change in the signal level of the communication crank signal (SYNCO). Execute.

  When the crank signal monitoring process is started, the microcomputers 11 and 31 determine whether or not the communication crank signal (SYNCO) input from the communication circuits 13 and 33 of the own device has changed to the active level (high). That is, it is determined whether or not an active edge (rising edge) of the communication crank signal (SYNCO) has been detected (S110). If it is determined that no active edge is detected (No in S110), the process proceeds to S115. On the other hand, in S115, it is determined whether or not the communication crank signal (SYNCO) has changed to an inactive level (low). That is, it is determined whether or not an inactive edge (falling edge) of the communication crank signal (SYNCO) is detected. If it is determined that the inactive edge of the communication crank signal (SYNCO) has not been detected (No in S115), the crank signal monitoring process is temporarily terminated, and the crank signal monitoring process is started again from S110 in the next cycle. To do. The microcomputers 11 and 31 repeatedly execute the crank signal monitoring process at a cycle sufficiently shorter than the time interval at which the active edge or the inactive edge of the communication crank signal (SYNCO) is detected.

  When the active edge of the communication crank signal (SYNCO) is detected (Yes in S110), the microcomputers 11 and 31 set the communication permission flag to off (S120) and set the crank flag to on (S130). The communication permission flag is a flag for notifying a transmission control process described later whether there is a communication line LN in a state where data transmission is possible. The communication permission flag is set to OFF when the communication crank signal (SYNCO) is at an active level, in other words, when the third differential signal is transmitted on the communication line LN, and the communication crank signal (SYNCO) is turned on. When it is at the active level, in other words, when the third differential signal is not transmitted on the communication line LN, it is set to ON. In addition, the crank flag is a flag for notifying the reception control process described later whether the data transmission is in an interrupted state, and is turned on when the communication crank signal (SYNCO) is at the active level. Is set to OFF when the communication crank signal (SYNCO) is at the inactive level.

  When the process in S130 is completed, the microcomputers 11 and 31 proceed to S140 and update the crank angle based on the communication crank signal (SYNCO) input this time. For example, when the communication crank signal (SYNCO) is a signal that changes to an active level every time the crank angle advances 10 degrees, the crank angle is updated 10 degrees here. The crank angle origin position is specified from the output signal of the cam angle sensor.

  When the processing in S140 is completed, the microcomputers 11 and 31 proceed to S150, and among the processing related to engine control, processing to be executed in synchronization with the crank signal (hereinafter referred to as “crank signal synchronization processing”). Execute. For example, the microcomputer 31 in the sub electronic control unit 30 determines whether or not the fuel injection timing notified from the main electronic control unit 10 has arrived based on the crank angle updated in S140. The process of driving the injector and performing fuel injection is executed as the crank signal synchronization process. In addition, the sub electronic control unit 30 may be configured to execute a process of acquiring a value of a pressure sensor or the like installed in the injector and transmitting a learning result related to fuel injection control as the crank signal synchronization process. it can.

  When the microcomputers 11 and 31 finish executing the crank signal synchronization process, the microcomputers 11 and 31 once terminate the crank signal monitoring process and start the process from S110 again in the next cycle. When the inactive edge (falling edge) of the communication crank signal (SYNCO) is detected (Yes in S115), the communication permission flag described above is set on (S160), and the crank flag described above is set off. (S170), the crank signal synchronization processing is terminated.

  Next, vehicle control processing executed by the microcomputer 11 of the main electronic control device 10 and the microcomputer 31 of each sub electronic control device 30 will be described. In this embodiment, when executing the process related to the engine control, the vehicle control including the process related to the engine control and the process of registering the transmission target data generated by the process related to the engine control in the queue. Execute the process. FIG. 6 is a flowchart showing the contents of this vehicle control process. That is, when the microcomputers 11 and 31 execute the process related to the engine control in S150 in synchronization with the communication crank signal (SYNCO), the vehicle control process shown in FIG. 6 is executed in S150 as the crank signal synchronization process. When executing the process related to engine control asynchronously with the communication crank signal (SYNCO), the vehicle control process shown in FIG. 6 is executed when the execution timing of the process related to engine control comes.

  When the vehicle control process is started, the microcomputers 11 and 31 execute a process related to the corresponding engine control (S210). For example, the microcomputer 11 of the main electronic control unit 10 calculates an optimal fuel injection amount and fuel injection timing in each cylinder as processing related to engine control, and based on the calculation result, the fuel injection amount and fuel to each cylinder. Processing for generating transmission target data storing the command value of the injection timing is executed. An example of the process related to engine control executed by the microcomputer 31 of the sub electronic control unit 30 is as described above.

  When the process related to engine control is executed (S210), the microcomputers 11 and 31 determine whether or not the transmission target data is generated by the process related to engine control executed in its own device (S220). If it is determined that no data has been generated (No in S220), the vehicle control process ends.

  On the other hand, when determining that data to be transmitted has been generated (Yes in S220), the microcomputers 11 and 31 proceed to S230 and register the data to be transmitted in a queue as transmission-waiting data. At this time, a reception number ReqNo is assigned to the transmission waiting data, and the transmission waiting data is registered in the queue in association with the reception number ReqNo. The initial value of the reception number ReqNo is zero. When the processing in S230 is completed, the microcomputers 11 and 31 increment the reception number ReqNo by 1, and update the reception number ReqNo of transmission waiting data to be registered next in the queue (S240). Thereafter, the vehicle control process ends.

  Next, transmission control processing that is repeatedly executed by the microcomputer 11 of the main electronic control device 10 and the microcomputer 31 of each sub electronic control device 30 will be described. FIG. 7 is a flowchart showing the contents of the transmission control process. However, some steps of the transmission control process shown in FIG. 7 are not executed in the sub electronic control unit 30. In FIG. 7, the processes of S330 to S350 that are not executed by the sub electronic control unit 30 are surrounded by a broken line. Hereinafter, the contents of the process executed by the microcomputer 11 as the transmission control process will be described, and the contents of the process executed by the microcomputer 31 will be omitted. However, when the microcomputer 31 determines Yes in S320, the next step is S370. Should be interpreted as a transition to Needless to say, the object to which the microcomputer 31 inputs the transmission data (TXD) in the transmission control process is the communication circuit 33 of the device itself.

  When the transmission control process is started, the microcomputer 11 first determines whether or not the transmission flag of its own device is set to ON (S310). When the transmission flag is on, it indicates that a data transmission operation is being performed via the communication circuit 13 of the own device. When the transmission flag is off, the data transmission operation via the communication circuit 13 of the own device is terminated. It is a flag indicating that

If it is determined that the transmission flag is set to ON (Yes in S310), the transmission control process is temporarily terminated, and the process is started again from S310.
On the other hand, if it is determined that the transmission flag is set to off (No in S310), it is determined whether or not the communication permission flag described above is set to on (S320). If it is determined that the communication permission flag is set to off (No in S320), the transmission control process is temporarily terminated, and the process waits until the communication permission flag is set to on. On the other hand, if it is determined that the communication permission flag is set to ON (Yes in S320), the process proceeds to the next step. That is, according to the microcomputer 11 of the main electronic control unit 10, the process proceeds to S330.

  After shifting to S330, the microcomputer 11 determines whether the signal level of the cam signal input from the input circuit 19 has changed from high to low or from low to high (S330). If it is determined that there is no change (No in S330), the process proceeds to S370. On the other hand, if it is determined that it has changed (Yes in S330), the process proceeds to S340. In S330, the signal level (high / low) of the cam signal after the change is stored every time the signal level of the cam signal changes, and is stored in the transmission control process executed after the next time. This can be realized by comparing the measured signal level with the current signal level.

  When the process proceeds to S340, the microcomputer 11 updates the value SndNo of the transmission pointer to a value decremented by one. The transmission pointer represents the reception number of transmission waiting data to be transmitted next. When this processing is completed, the microcomputer 11 proceeds to S350, generates cam state data representing the high / low state of the cam signal after the change, and presents the current value indicated by the transmission pointer for this cam state data. Assign the same receipt number. Furthermore, this cam state data is registered in a queue together with the above reception number as transmission waiting data. According to the present embodiment, the cam state data is registered in the queue in this way, so that the cam state data is transmitted with priority over other transmission waiting data. Note that the transmission pointer value SdNo is decremented by 1 in S340 because the transmission waiting data corresponding to the transmission pointer value SdNo before decrementing by 1 has not been transmitted yet, but the reception number one before it. This is because the data having “” is already transmitted and deleted from the queue. After finishing the process of S350, the microcomputer 11 proceeds to S370.

  In step S370, the microcomputer 11 determines whether there is unprocessed transmission waiting data in the queue of the own apparatus. Specifically, the reception number ReqNo to be assigned to the next transmission-waiting data is compared with the value SndNo indicated by the transmission pointer, and if the value SndNo indicated by the transmission pointer is less than the reception number ReqNo, It is determined that there is processing-waiting data, and if the value SndNo indicated by the transmission pointer is greater than or equal to the receipt number ReqNo, it is determined that there is no unprocessed transmission-waiting data.

  If it is determined that there is no unprocessed transmission waiting data (No in S370), the microcomputer 11 ends the transmission control process and determines that there is unprocessed transmission waiting data (Yes in S370). The transmission waiting data to which the reception number ReqNo that matches the value indicated by the transmission pointer SndNo is assigned is input as transmission data (TXD) to the communication circuit 13 of the own device, whereby the transmission data is transmitted through the communication circuit 13 of the own device. (TXD) is transmitted to another electronic control unit (S380). When transmission data (TXD) is input to the communication circuit 13 by the microcomputer 11, the transmission data is converted into a differential signal and output to the communication line LN. However, the data transmission operation for outputting the transmission waiting data as transmission data (TXD) includes a communication procedure according to a communication protocol such as communication arbitration.

  Further, after such data transmission operation is started, the transmission flag is set to ON (S390). Thereafter, the microcomputer 11 once ends the transmission control process, and starts the process again from S310.

  The transmission flag is set to OFF by the reception control process described below. The microcomputer 11 of the main electronic control unit 10 and the microcomputer 31 of each sub electronic control unit 30 repeatedly execute the reception control process shown in FIG.

  When the reception control process is started, the microcomputers 11 and 31 determine whether or not the reception data is registered in the reception buffer of its own device, so that an unprocessed reception in which the data fetch operation from the buffer is not completed. Determine whether data exists. If it is determined that there is no unprocessed received data (No in S410), the reception control process is temporarily terminated.

  On the other hand, if it is determined that there is unprocessed received data (Yes in S410), it is determined whether or not the crank flag of the own apparatus is set on (S420), and it is determined that the crank flag is set on. Then (Yes in S420), the reception data registered in the reception buffer is discarded (S430), the transmission flag is set to off (S440), and the reception control process is terminated.

  The reason why the transmission flag is set to OFF in S440 is to retransmit the transmission data in which the data transmission operation is interrupted due to the third differential signal being input to the communication line LN. In this embodiment, as described above, the transmission waiting data of the reception number corresponding to the value SndNo indicated by the transmission pointer is processed as transmission data. Therefore, if the transmission flag is set to OFF without updating the value SndNo of the transmission pointer. Through the process of S380 described above, the same transmission waiting data is output again to the communication circuits 13 and 33 as transmission data (TXD).

  In addition, the processing of S430 and S440 can be executed even when there is an abnormality in the differential communication between the electronic control units 10 and 30. That is, in S420, if the crank flag is set to ON or an abnormality has occurred in the differential communication between the electronic control units 10 and 30, an affirmative determination is made, the crank flag is set to OFF, and Only when there is no abnormality in the differential communication between the electronic control units 10 and 30, a negative determination can be made.

  If a negative determination is made in S420 (No in S420), the microcomputers 11 and 31 move to S460 and determine whether or not the reception data registered in the reception buffer is transmission data from the own device (S460). When it is determined that the reception data registered in the reception buffer is transmission data from the own device (Yes in S460), the transmission pointer value SndNo is incremented by 1, and output as transmission data (TXD). The data waiting for transmission is changed to the data with the next receipt number (S470).

Thereafter, the microcomputers 11 and 31 discard the received data registered in the reception buffer, set the transmission flag to OFF (S480), and then temporarily terminate the reception control process.
On the other hand, if it is determined that the received data registered in the reception buffer is not the transmission data from the own device (No in S460), the microcomputers 11 and 31 move to S490 and use the received data as the reception buffer of the own device. Capture from. The microcomputers 11 and 31 further classify the data fetched in this way, and deliver each data to the tasks in the microcomputers 11 and 31 that need the data.

  For example, when the microcomputer 31 of the sub electronic control unit 30 receives data including information on the fuel injection amount and the fuel injection timing from the main electronic control unit 10, the microcomputer 31 delivers the received data to a task related to fuel injection control. The task relating to the fuel injection control performs fuel injection control of the corresponding cylinder based on the information on the fuel injection amount and the injection timing indicated by the received data. For example, in the crank signal synchronization process (S150) executed as one of the tasks related to fuel injection control, the microcomputer 31 of the sub electronic control unit 30 is based on the fuel injection amount and injection timing information indicated by the received data. The fuel injection control of the corresponding cylinder is performed.

Then, when the process in S490 is finished, the microcomputers 11 and 31 once end the reception control process.
Although the configuration of the vehicle control system 1 of the present embodiment has been described above, according to the vehicle control system 1 of the present embodiment, the crank signal (SYNCI) input from the input circuit 17 is active as shown in FIG. A third differential signal, which is a special differential signal, is input to the communication line LN during the period until the crank signal changes to the inactive level (low) every time the level (high) changes. The sub electronic control unit 30 is notified that the signal has changed to the active level. In the sub electronic control unit 30, a communication crank signal (SYNCO) which is a pseudo signal of a crank signal whose signal level changes between an active level and an inactive level in accordance with the input pattern of this special differential signal. Is input to the microcomputer 31. The microcomputer 31 executes processing related to engine control (crank signal (NE) synchronization processing shown in FIG. 9) according to the change in the crank angle based on the communication crank signal (SYNCO). Therefore, according to this embodiment, the input circuit 17 for inputting the output signal of the crank angle sensor 21 to the sub electronic control device 30 is not provided in the same manner as the main electronic control device 10, but the sub electronic control device 30 is provided. Processing synchronized with the crank signal can be appropriately executed.

  Further, according to this embodiment, in the main electronic control unit 10 as well, engine control corresponding to a change in the crank angle is performed based on the communication crank signal (SYNCO) instead of the crank signal (SYNCI) input from the input circuit 17. (Crank signal (NE) synchronization process shown in FIG. 9) is executed. Therefore, the processing operation between the main electronic control device 10 and the sub electronic control device 30 is suppressed, and the processing related to engine control is appropriately executed by the cooperation of the plurality of electronic control devices 10 and 30. can do.

  In addition, according to the present embodiment, the information on the crank signal is transmitted through the communication line LN and the communication circuits 13 and 33 that are less affected by signal delay and noise, so that each electronic control device 10 including the sub electronic control device 30, 30, a process synchronized with the crank signal in each electronic control device 10, 30 with higher accuracy than the case where the input circuit 17 is provided and the output signal of the crank angle sensor 21 is directly input to each electronic control device 10, 30. Can be executed.

  Further, according to the present embodiment, the communication circuit 13 generates the special differential signal (third differential signal) indicating that the crank signal has changed to the active level without using the microcomputer 11. Compared to the case where such a differential signal is generated via the microcomputer 11, the transmission delay of the special differential signal can be suppressed, and the processing synchronized with the crank signal (SYNCI) is performed by each electronic control unit 10, 30 can be performed with high accuracy.

  In addition, during the period in which the special differential signal is transmitted, data communication between the electronic control units 10 and 30 is interrupted. However, according to the electronic control units 10 and 30 of the present embodiment, the transmission pointer The transmission data that was interrupted was retransmitted from the transmission source by temporarily switching the transmission flag off without changing the value SndNo. Therefore, according to the present embodiment, transmission of the differential signal indicating that the crank signal has changed to the active level using the communication line LN and data communication using the communication line LN can be appropriately made compatible. .

  In addition, according to the present embodiment, information related to the output signal of the cam angle sensor 23 is also transmitted to each sub electronic control unit 30 by data communication, so that the input circuit 19 corresponding to the cam angle sensor 23 is also sub It is not necessary to provide it in the electronic control unit 30, and it is very convenient.

By the way, this invention is not limited to the said Example, A various aspect can be taken.
For example, in the above embodiment, the main electronic control unit 10 is configured so that the crank signal (SYNCI) is directly input from the input circuit 17 to the communication circuit 13 without using the microcomputer 11. As shown in FIG. 10, the crank signal (SYNCI) may be input from the input circuit 17 to the communication circuit 13 via the microcomputer 11 ′ (first modification). According to the modified vehicle control system 1 ′ adopting the configuration in which the crank signal (SYNCI) is input from the input circuit 17 to the microcomputer 11 ′, the input cycle of the crank signal (SYNCI) to the communication circuit 13 can be easily made. Thus, the difference in the standard of the crank angle sensor can be absorbed, and a uniform crank signal (SYNCI) can be input to the communication circuit 13. For example, the microcomputer 11 ′ may be provided with a crank signal (SYNCI) conversion function 11b. The microcomputer 11 ′ uses the conversion function 11b to convert the crank signal (SYNCI) input from the input circuit 17 to the crank angle. The signal level can be converted to a crank signal that changes to an active level each time the signal changes by a specified amount, and can be input to the communication circuit 13. For example, every time the crank angle changes by 5 degrees or 6 degrees, an output signal from a crank angle sensor that outputs a crank signal whose signal level becomes active is output for each crank angle requested by the vehicle control system 1 ′ (for example, every 10 degrees). ) Is converted into a crank signal (SYNCI) in which the signal level becomes active, and the process of inputting to the communication circuit 13 can be executed by the microcomputer 11 ′. If the microcomputer 11 ′ executes such processing, the microcomputer 11 ′ can easily absorb the difference in standards for each crank angle sensor and input an appropriate crank signal to the communication circuit 13.

  Further, according to the embodiment, as the third differential signal, a differential signal in which the first signal line L1 is 5V and the second signal line L2 is 0V is input to the communication line LN. However, the third differential signal may be a differential signal (see FIG. 12) obtained by simply switching the first signal line L1 to 5 V (second modification).

  That is, the transmission circuit 14 may be changed to the transmission circuit 40 including the inverters IV41, IV42, IV43 and the transistors TR41, TR42, TR43 in a connection relationship as shown in FIG. According to this circuit configuration, when the crank signal (SYNCI) input from the input circuit 17 is low and the input (TXD) from the microcomputer 11 is “1” (high), the N-type transistor TR41 is turned on, Since the P-type transistor TR42 is turned on and the P-type transistor TR43 is turned off, the first differential signal is transmitted to the communication line LN as shown in FIG. On the other hand, when the crank signal (SYNCI) input from the input circuit 17 is low and the input (TXD) from the microcomputer 11 is “0”, the N-type transistor TR41 is turned off and the P-type transistor TR42 is turned off. Since the P-type transistor TR43 is turned off, the second differential signal is transmitted to the communication line LN.

  Further, when the crank signal (SYNCI) input from the input circuit 17 is high (active level), the P-type transistor TR43 is turned on, and as shown in FIG. One signal line L1 is set to 5 V corresponding to the power supply voltage.

  Also with such a transmission circuit 40, the information of the crank signal can be appropriately transmitted to the sub electronic control unit 30. However, when such a transmission circuit 40 is used, the reception circuits 15 and 35 of the main electronic control device 10 and the sub electronic control device 30 are changed to the reception circuit 50 shown in FIG.

  That is, for the comparator CM51 for generating the communication crank signal (SYNCO), the first signal line L1 is connected to the plus input terminal, and a fixed voltage (greater than 3.5V and less than 5V is connected to the minus input terminal. For example, the receiver circuit 50 is provided in a state where a circuit for applying 4 V) is connected. According to the reception circuit 50 shown in FIG. 11B configured as described above, during the period in which the third differential signal is transmitted through the communication line LN, the communication crank signal ( The signal level of (SYNCCO) becomes the active level, and the signal level of the communication crank signal (SYNCO) becomes the ink active level during other periods. If the receiving circuit 50 is configured in this manner in accordance with the configuration of the transmitting circuit 40, the crank signal information can be appropriately transmitted to the sub electronic control unit 30.

In addition, the third differential signal may be a differential signal (see FIG. 14) obtained by simply switching the first signal line L2 to 0 V (third modified example).
That is, the transmission circuit 14 may be changed to a transmission circuit 60 including inverters IV61, IV62, IV63, IV64 and transistors TR61, TR62, TR63 in a connection relationship as shown in FIG. According to this circuit configuration, when the crank signal (SYNCI) input from the input circuit 17 is high, the N-type transistor TR63 is turned on, as shown in FIG. 14, regardless of the state of the transistor TR61. The first signal line L2 is set to 0V, and the first signal line L1 is set to a potential corresponding to the input (TXD) from the microcomputer 11.

  Furthermore, according to the configuration of the transmission circuit 60, the reception circuits 15 and 35 of the main electronic control device 10 and the sub electronic control device 30 can be changed to the reception circuit 70 shown in FIG.

  That is, for the comparator CM71 for generating the communication crank signal (SYNCO), the second signal line L2 is connected to the minus input terminal, and a fixed voltage (greater than 0V and less than 1.5V is connected to the plus input terminal. For example, the receiver circuit 70 can be provided in a state where a circuit for applying 1 V) is connected. According to the reception circuit 70 shown in FIG. 13B configured as described above, the communication crank signal output from the comparator CM71 during the period in which the third differential signal is transmitted through the communication line LN. The signal level of (SYNCO) is the active level, and the signal level of the communication crank signal (SYNCO) is the ink active level during other periods. Therefore, if the transmission circuit 60 and the reception circuit 70 are configured in this way, the information of the crank signal can be appropriately transmitted to the sub electronic control unit 30.

In addition, in the said Example, although the microcomputer was provided in the electronic control apparatuses 10 and 30, it cannot be overemphasized that it may replace with a microcomputer and a dedicated IC may be provided.
6 and 7, the embodiment has been described using an example in which data is transmitted in the queued order. However, the order in which data is transmitted is not limited to the queued order. For example, the data may be transmitted according to the priority order set for each data in the CAN.

  Finally, the correspondence between terms will be described. The processing realized by the input circuit 17 (and the crank signal conversion function 11b included in the microcomputer 11 ′) corresponds to an example of processing realized by the crank signal input means, and the input circuit 17 is an example of the crank signal input circuit. Corresponding to Further, the processing realized by the transmission circuits 14, 40, 60 and the processing executed by the microcomputer 11 such as S310, S320, S340, S370, S380, S390, S440, S470, S480, etc. are processing realized by the transmission control means. Corresponds to an example. The comparator CM0 included in the receiving circuits 15, 35, 50, and 70 corresponds to an example of a data receiving means (circuit). Circuit configurations other than the comparator CM0 included in the receiving circuits 15, 35, 50, and 70 are as follows. This corresponds to an example of the pseudo signal generation means (circuit). In addition, the input circuit 19 corresponds to an example of a cam signal input unit (circuit), and the processing of S330 and S350 executed by the microcomputer 11 corresponds to an example of processing realized by the cam state data generation unit.

DESCRIPTION OF SYMBOLS 1,1 '... Vehicle control system 10,30 ... Electronic control apparatus 11,31,11' ... Microcomputer (microcomputer), 11a, 31a ... Memory, 11b ... Conversion function, 13,33 ... Communication circuit 14, 34, 40, 60 ... transmitting circuit, 15, 35, 50, 70 ... receiving circuit, 17, 19 ... input circuit, 21 ... crank angle sensor, 23 ... cam angle sensor, AG ... AND circuit, CM0, CM1, CM2, CM51, CM71 ... comparators, IV1-4, IV41-43, IV61-64 ... inverters, TR1-4, TR41-43, TR61-63 ... transistors, R11, R12, R31-R33 ... resistors, L1, L2 ... signals Line, LN ... Communication line

Claims (10)

A vehicle control system comprising a plurality of vehicle control devices connected to a communication line for differential communication, and realizing control of an internal combustion engine mounted on the vehicle by cooperation of the plurality of vehicle control devices with communication. And
A first vehicle control device that is one of the plurality of vehicle control devices,
Crank signal input means for inputting a crank signal whose signal level changes between an active level and an inactive level in accordance with a change in crank angle in the internal combustion engine;
When data to be transmitted is converted into a differential signal for data transmission and output to the communication line, while the signal level of the crank signal input from the crank signal input means changes to the active level A transmission control means for outputting a special differential signal different from the differential signal for data transmission to the communication line instead of the differential signal for data transmission for a predetermined period;
With
Of the plurality of vehicle control devices, a second vehicle control device different from the first vehicle control device is:
Based on an input signal from the communication line, data receiving means for generating reception data that is converted into the differential signal for data transmission and restored to the transmission target data output to the communication line;
Based on an input signal from the communication line, a signal whose signal level changes between an active level and an inactive level according to an input pattern of the special differential signal, and the special differential signal is Pseudo signal generating means for generating a pseudo signal of the crank signal whose signal level changes to an active level each time it is input;
The vehicle control system is characterized in that the processing related to the control of the internal combustion engine is executed based on the received data and the pseudo signal generated by the pseudo signal generating means included in the own apparatus. The first vehicle control device includes the pseudo signal generation means for generating the pseudo signal of the crank signal based on an input signal from the communication line, similarly to the second vehicle control device, and the internal combustion engine The vehicle control system according to claim 1, wherein processing related to engine control is configured to be executed on the basis of the pseudo signal generated by the pseudo signal generation means included in the device itself. The transmission control means included in the first vehicle control device is caused by the fact that the signal level of the crank signal is changed to the active level and the output operation of the special differential signal to the communication line is started. After the operation to output the special differential signal to the communication line is completed, the data to be transmitted, which is converted to the differential signal for data transmission and output to the communication line is interrupted, The data to be transmitted is retransmitted by converting the data again into a differential signal for data transmission and outputting the differential signal to the communication line. Vehicle control system. The first vehicle control device includes:
Cam signal input means for inputting a cam signal whose signal level changes between an active level and an inactive level in accordance with a change in cam angle in the internal combustion engine;
When the signal level of the cam signal input from the cam signal input means is switched to the active level, cam status data indicating that the signal level of the cam signal is the active level is generated as the transmission target data. State data generating means;
With
The transmission control means included in the first vehicle control device is configured such that the cam state data generated by the cam state data generating means is prioritized over the other data to be transmitted, and the differential for data transmission is performed. The vehicle control system according to claim 1, wherein the vehicle control system converts the signal into a signal and outputs the signal to the communication line. A vehicle control system comprising a plurality of vehicle control devices connected to a communication line for differential communication, and realizing control of an internal combustion engine mounted on the vehicle by cooperation of the plurality of vehicle control devices with communication. And
A first vehicle control device that is one of the plurality of vehicle control devices,
A transmission circuit;
A microcomputer for executing processing related to control of the internal combustion engine and inputting data to be transmitted to the transmission circuit;
A crank signal input circuit that inputs a crank signal whose signal level changes between an active level and an inactive level according to a change in crank angle in the internal combustion engine to the transmission circuit;
As the transmission circuit, the transmission target data input from the microcomputer is converted into a differential signal for data transmission and output to the communication line, while being input from the crank signal input circuit When the signal level of the crank signal changes to the active level, a special differential signal different from the differential signal for data transmission is used instead of the differential signal for data transmission for a predetermined period. It is configured with a circuit that outputs to the communication line,
Of the plurality of vehicle control devices, a second vehicle control device different from the first vehicle control device is:
A data reception circuit that generates reception data obtained by restoring the transmission target data that is converted to the differential signal for data transmission and output to the communication line based on an input signal from the communication line;
Based on an input signal from the communication line, a signal whose signal level changes between an active level and an inactive level according to an input pattern of the special differential signal, and the special differential signal is A pseudo signal generation circuit that generates a pseudo signal of the crank signal whose signal level changes to an active level each time it is input;
The vehicle control is configured to execute processing related to the control of the internal combustion engine based on the received data and the pseudo signal generated by the pseudo signal generation circuit included in the device. system. The crank signal input circuit included in the first vehicle control device inputs the crank signal to the microcomputer included in the first vehicle control device instead of the transmission circuit,
The microcomputer included in the first vehicle control device uses a crank signal input from the crank signal input circuit as a specified crank signal whose signal level changes to an active level whenever the crank angle changes by a specified amount. And then input to the transmission circuit,
The vehicle control system according to claim 5, wherein the transmission circuit outputs the special differential signal to the communication line based on the crank signal input from the microcomputer. The first vehicle control device includes the pseudo signal generation circuit that generates the pseudo signal of the crank signal based on an input signal from the communication line, similarly to the second vehicle control device,
The microcomputer included in the first vehicle control device executes processing related to control of the internal combustion engine based on the pseudo signal input from the pseudo signal generation circuit included in the device. The vehicle control system according to claim 5 or 6. The microcomputer included in the first vehicle control device detects that the pseudo signal input from the pseudo signal generation circuit has changed to the active level, whereby the special differential signal by the transmission circuit is detected. When the output operation to the communication line is detected, the differential transmission for data transmission by the transmission circuit is caused due to the start of the output operation of the special differential signal to the communication line. The data to be transmitted whose operation of converting to a signal and outputting to the communication line is interrupted is input to the transmission circuit again after the output operation of the special differential signal to the communication line is completed. The vehicle control system according to claim 7, wherein the data to be transmitted is retransmitted. The first vehicle control device includes a cam signal input circuit that inputs a cam signal whose signal level changes between an active level and an inactive level according to a change in a cam angle in the internal combustion engine,
The microcomputer included in the first vehicle control device indicates that the signal level of the cam signal is an active level when the signal level of the cam signal input from the cam signal input circuit is switched to an active level. The cam state data is generated as the transmission target data, and the cam state data is input to the transmission circuit in preference to the other transmission target data. The vehicle control system according to any one of the above. Vehicle control connected to a communication line for differential communication and controlling an internal combustion engine mounted on the vehicle in cooperation with the other vehicle control device by communicating with the other vehicle control device through the communication line A device,
Crank signal input means for inputting a crank signal whose signal level changes between an active level and an inactive level in accordance with a change in crank angle in the internal combustion engine;
When data to be transmitted is converted into a differential signal for data transmission and output to the communication line, while the signal level of the crank signal input from the crank signal input means changes to the active level A transmission control means for outputting a special differential signal different from the differential signal for data transmission to the communication line instead of the differential signal for data transmission for a predetermined period;
The vehicle control device is configured to transmit a signal representing a change in signal level of the crank signal to the other vehicle control device by the special differential signal.

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