JP2011174397A - Control device of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid the delay of processing while connecting the microcomputer, the driver IC, and the input processing IC of a control device of an internal combustion engine for an automobile through a serial communication. <P>SOLUTION: This control device of an internal combustion engine includes an input signal processing circuit for transmitting an input signal based on signals from various sensors, the microcomputer for transmitting an output signal for controlling the state of the automobile based on the input signal, an output driver circuit for driving the various actuators based on the output signal, and a communication line for connecting the input signal processing circuit, the microcomputer, and the output driver circuit through the synchronous serial communication. The control device further includes at least either a first timing control signal transmission means which is installed between the input signal circuit and the microcomputer and transmits a timing control signal from the input signal processing circuit to the microcomputer, or a second timing control signal transmission means which is installed between the microcomputer and the output driver circuit and transmits a timing control signal from the microcomputer to the output driver circuit. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an internal combustion engine controller for an automobile.

  In general, an internal combustion engine controller for an automobile is composed of a microcomputer, an input signal processing circuit, and an output driver circuit. The input signal processing circuit processes signals from various sensors and delivers them to the microcomputer. The microcomputer controls the various actuators by driving the output driver circuit based on these input signals so as to obtain an optimum operating state.

  Here, in recent output driver circuits, driver ICs in which power MOSFETs are integrated for a plurality of channels and a serial communication interface and the like are integrated on a single chip have come to be used. When such a driver IC is used, an ON / OFF signal for driving the relay switch can be transmitted from the microcomputer to the driver IC via a serial communication line. The PWM signal and the pulse signal are individually created for each actuator based on a timer built in the microcomputer, and are individually transmitted to the driver IC.

  In the system in which the PWM signal and the pulse signal are individually transmitted from the microcomputer to various actuators, the number of pins of the package and the number of wirings between the ICs in the microcomputer and the driver IC increase as the function of the internal combustion engine controller increases. As the number of pins increases, the package size per pin increases, making it difficult to achieve both downsizing and higher functionality of the internal combustion engine control device. Although there is a method of mounting an IC with a BGA package to reduce the size of the package, it is disadvantageous in terms of cost. In addition, since the number of timer ports of the microcomputer increases, the manufacturing cost of the microcomputer also increases.

  Therefore, a method is disclosed in which a timer is incorporated in an output driver IC instead of a microcomputer, and a clock signal for time synchronization or engine rotation synchronization is supplied from the microcomputer to the output driver IC as a clock signal for the timer (patent) Reference 1).

  In the synchronous serial communication for transmitting a command from the master device to a plurality of slave devices, when the master device transmits a command to the slave device to be communicated, the slave device to be communicated with the command to be transmitted When the slave device receives the command frame from the master device, the slave device outputs the command frame based on the destination slave information included in the command frame. Determine whether the frame is addressed to itself, and if it is addressed to itself, perform processing based on the command in the command frame, and if at least two of the plurality of slave devices have the same slave identifier, external Auxiliary identifier is provided to distinguish it from the Serial communication system providing a communication target slave identifier and the auxiliary identifier is disclosed as a slave information (see Patent Document 2).

JP 2004-339777 A Japanese Patent Laid-Open No. 2004-362067

  According to Patent Document 1, it is necessary to always output a clock signal for a timer from the microcomputer to the driver IC, and there is a problem that the circuit between the microcomputer and the driver IC and the timer configuration of the driver IC are complicated.

  Further, according to Patent Document 2, in order to validate the auxiliary identifier on the slave side, a signal pin for identification is required on the slave side, and when a plurality of commands are transmitted, the communication target in the command frame The slave identifier and the auxiliary identifier are omitted, so if a large amount of communication occurs, a waiting time occurs in other processing, and therefore, it is unsuitable for an internal combustion engine control device for automobiles that should be driven with priority on timing. There are challenges.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an internal combustion engine control apparatus that reduces the number of pins around a microcomputer and its surroundings, and does not generate a waiting time for processing whose timing is important even when a large amount of communication occurs. is there.

  In order to solve the above problems, one of the desirable aspects of the present invention is as follows.

  The internal combustion engine control device includes an input signal processing circuit that transmits an input side signal based on signals from various sensors, a microcomputer that transmits an output side signal for controlling the state of the vehicle based on the input side signal, and an output side It has an output driver circuit that drives various actuators based on signals, an input signal processing circuit, a microcomputer, and a communication line that connects the output driver circuit by synchronous serial communication, and is provided between the input signal circuit and the microcomputer A first timing control signal transmitting means for transmitting a timing control signal from the input signal processing circuit to the microcomputer; and a first timing control signal transmitting means provided between the microcomputer and the output driver circuit for transmitting the timing control signal from the microcomputer to the output driver circuit. At least one of the two timing control signal transmission means is provided.

  According to the present invention, it is an object to provide an internal combustion engine controller that reduces the number of pins around a microcomputer and does not generate a waiting time for a process in which timing is important even when a large amount of communication occurs.

1 is a block diagram illustrating an overall configuration of Embodiment 1. FIG. FIG. 3 is a diagram illustrating a command frame configuration of serial communication according to the first embodiment. FIG. 2 is a block diagram illustrating a part of the first embodiment. The figure which shows the timing control in the structure of FIG. FIG. 2 is a block diagram illustrating a part of the first embodiment. The figure which shows the timing control in the structure of FIG. FIG. 3 is a diagram illustrating timing control in the first embodiment. FIG. 9 is a block diagram showing a part of the second embodiment. FIG. 9 is a block diagram illustrating a part of the third embodiment. FIG. 10 is a block diagram illustrating a part of the fourth embodiment. FIG. 10 is a block diagram illustrating a part of the fifth embodiment. FIG. 10 is a block diagram illustrating a part of the sixth embodiment.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows the overall configuration of the internal combustion engine control apparatus according to the first embodiment.

  The internal combustion engine control device includes a microcomputer 1 and at least two output driver ICs 2A and 2B that are output driver circuits or at least two input processing ICs 3A and 3B that are input processing circuits.

  Note that other components such as an input circuit, an output circuit, a communication circuit, and a power supply circuit are not shown.

  The microcomputer 1 includes a CPU 101, a ROM 102, a RAM 103, an A / D converter 104, a timer 105, and a serial communication interface 106.

  The CPU 101 receives input signals such as A / D intake air amount, intake pressure, accelerator opening, electronic throttle opening, various temperature sensors, various switch signals, crank angle sensors, and the like, and an output driver according to a program built in the ROM 102 Controls injectors, igniters, electronic throttle motors, various solenoids, various relays, and the like driven by the ICs 2A and 2B and other output driver ICs.

  Here, the signals for driving the electronic throttle motor and various solenoids include a pulse width modulation (PWM) signal and a high / low signal corresponding to on / off. The signal for driving the injector and the igniter is a pulse signal synchronized with the engine rotation, and the signal for driving various relays is a High / Low signal corresponding to on / off.

  The serial communication interface 106 performs serial communication based on a command from the CPU 101. The serial communication referred to here is synchronous serial communication having the following configuration. The master device is the microcomputer 1, the slave devices are the output driver ICs 2A and 2B, and the input processing ICs 3A and 3B. A serial output signal 111 (also referred to as a Tx signal) serving as a data output signal from the master device to the slave device, a serial input signal 112 (also referred to as an Rx signal) serving as a data input signal from the slave device to the master device, and these The microcomputer 1 as a master device, the output drivers IC2A and 2B as slave devices, and the input processing ICs 3A and 3B are connected by three common signal lines of the serial clock signal 113 to be synchronized with the signal.

  The input processing ICs 3A and 3B receive input signals such as A / D intake air amount, intake pressure, accelerator opening, electronic throttle opening, various temperature sensors, various switch signals, and crank angle sensors by the input signal processing circuit 302. . Among these input signals, an analog signal is a digital signal obtained by performing A / D conversion according to the voltage level of the signal, and a High / Low signal is “1” when the signal is at a high level, and “0” when the signal is at a low level. Are transmitted to the communication I / F circuit 301, and the state of various connected input signals is transmitted to the microcomputer 1 by serial communication in accordance with a command transmitted from the microcomputer 1 as a master device by serial communication. .

  The input processing ICs 3A and 3B are ICs having the same configuration. Depending on the level of the input signal to the auxiliary identification circuit 303, the input processing ICs 3A and 3B and itself (for example, the input processing IC 3A) and other ICs having the same configuration as itself ( For example, a signal for identifying the input processing IC 3 B) is transmitted from the auxiliary identification circuit 303 to the communication I / F circuit 301. In the case of FIG. 1, the input signal of the auxiliary identification circuit 303 of the input processing IC 3A becomes a low signal by the pull-down resistor 304 inside the IC because there is no signal connected to the outside of the IC. Is transmitted to the communication I / F circuit 301. The input signal of the auxiliary identification circuit 303 of the input processing IC 3B becomes a high signal because the high-level power source 305 is connected to the outside of the IC, and the auxiliary identification circuit 303 of the input processing IC 3B sets “1” to the communication I / F circuit 301. To communicate. Depending on the signal level of the auxiliary identification circuit 303, if the command transmitted by the serial communication from the microcomputer 1 is directed to itself, it responds to the command and the status of the various input signals connected is serial communication. To the microcomputer 1.

  The output driver ICs 2A and 2B receive a command transmitted by serial communication from the microcomputer 1 serving as a master device by the communication I / F circuit 201 and control the ON / OFF state of the target driver circuit 203 according to the contents of the command. When the content of the command is a pulse width modulation (PWM) signal or a pulse signal, the target driver circuit 203 is controlled using the timer circuit 202. In this way, the injector, igniter, electronic throttle motor, various solenoids, various relays and the like are controlled.

  The output driver ICs 2A and 2B are ICs having the same configuration. Depending on the level of the input signal to the auxiliary identification circuit 204, the output driver ICs 2A and 2B are themselves (for example, the output driver IC 2A) and other ICs having the same configuration ( For example, a signal for identifying the output driver IC 2 B) is transmitted from the auxiliary identification circuit 204 to the communication I / F circuit 201. In the case of FIG. 1, the input signal of the auxiliary identification circuit 204 of the output driver IC 2A becomes a Low signal by the pull-down resistor 205 inside the IC because there is no signal connected to the outside of the IC, and the auxiliary identification circuit 204 of the output driver IC 2A Is transmitted to the communication I / F circuit 201. The input signal of the auxiliary identification circuit 204 of the output driver IC 2B becomes a high signal because the high-level power source 206 is connected to the outside of the IC, and the auxiliary identification circuit 204 of the output driver IC 2B sets “1” to the communication I / F circuit 201. To communicate. If the command transmitted from the microcomputer 1 by serial communication is directed to itself due to the signal level of the auxiliary identification circuit 204, the driver circuit 204 that responds to the command and drives the various connected outputs is displayed. Control.

  Next, the configuration of a command frame for serial communication will be described with reference to FIG.

  FIG. 2A shows the contents of a serial communication command frame in the first embodiment.

  Serial communication for connecting the microcomputer 1 serving as a master device, the output driver ICs 2A and 2B serving as slave devices, and the input processing ICs 3A and 3B includes a slave identifier 21, a slave auxiliary identifier 31, commands, data, and the like 41 in this order. Command frame 11 is a communication unit.

  The slave identifier 21 indicates the type of the slave side IC (output driver ICs 2A and 2B, input processing ICs 3A and 3B) and indicates a communication target. The slave auxiliary identifier 31 is used to distinguish each IC when two or more identically configured slave side ICs are to be communicated. Commands, data, etc. 41 are commands and data to be delivered to the slave IC to be communicated as shown in FIG. 2B (for example, communication channel, presence / absence of PWM, signal frequency, DUTY value, which will be described later) Timing control), or data (for example, communication channel, signal level, presence / absence of timing control) returned by the slave IC to be communicated as shown in FIG. 2C.

  The command frame 11 is configured in the order of the slave identifier 21, the slave auxiliary identifier 31, the command, the data, and the like 41 in all communication after the second time, not limited to the first time, and none of them is omitted. For example, a command frame 1N in N-th communication (N: a natural number of 2 or more) is configured in the order of a slave identifier 2N, a slave auxiliary identifier 3N, commands, data, and 4N. As described above, by assigning the slave identifier 21 and the slave auxiliary identifier 31 to all the command frames 11, compared with a method in which these identifiers are omitted, the slave-side IC to be communicated is frequently switched. A processing speed suitable for control can be realized.

  FIG. 3 shows a configuration around the timing control signal transmission line on the output driver circuit side in the first embodiment.

  The output driver ICs 2 </ b> A and 2 </ b> B receive a command transmitted by the serial communication from the microcomputer 1 serving as the master device by the communication I / F circuit 201 and control the ON / OFF state of the target driver circuit 203 according to the contents of the command. To do. When the content of the command is a pulse width modulation (PWM) signal or a pulse signal, the target driver circuit 203 is controlled using the timer circuit 202. At this time, if the control of the target driver circuit 203 needs to be performed at a time interval shorter than the time interval that can be transmitted by serial communication, it is output from the timer 105 incorporated in the microcomputer 1 and incorporated in the output driver IC 2A. The output side timing control signal 114 input to the communication I / F circuit 201 is used.

  FIG. 4 shows an example of controlling the target driver circuit 203 using the output side timing control signal 114. As a serial communication command, during the one-shot pulse period 222, a signal for turning on the driver signal 221 is transmitted to the communication I / F circuit 201 built in the output driver IC 2A, and the transmitted contents are executed. As the execution timing 114A, an edge change (High → Low or Low → High) of the output side timing control signal 114 is transmitted. In response to this output execution timing 114A, the communication I / F circuit 201 transmits a driver control signal 220 to the driver circuit 203 in accordance with a command transmitted in advance by serial communication. The driver circuit 203 turns on the target driver signal 221 during the one-shot pulse period 222 in accordance with this signal.

  By doing this, even when it is necessary to control the target driver circuit 203 at a time interval shorter than the time interval that can be transmitted by serial communication, the timer circuit 202 built in the output driver IC 2A is counted. There is no need to supply a time-synchronized clock signal or engine-rotation-synchronized clock signal from the microcomputer to the output driver IC as a clock signal for this purpose, and the circuit between the microcomputer 1 and the output driver IC 2A and the timer configuration of the driver IC It can be simplified.

  FIG. 5 shows a configuration around the timing control signal transmission line on the input processing circuit side in the first embodiment.

  The input processing IC 3A receives the input signal by the input signal processing circuit 302, the analog signal is a digital signal obtained by performing A / D conversion in accordance with the voltage level of the signal, and the High / Low signal is high level. , “1”, when the level is Low, a digital signal of “0” is transmitted to the communication I / F circuit 301 and connected according to a command transmitted from the microcomputer 1 as a master device by serial communication. The state of the input signal is transmitted to the microcomputer 1 by serial communication. At this time, when it is necessary to transmit the change of the target input signal 306 to the microcomputer 1 at a time interval shorter than the time interval that can be transmitted by serial communication, the communication I / F circuit 301 built in the input processing IC 3A. The input side timing control signal 115 input to the timer 105 built in the microcomputer 1 is used.

  FIG. 6 is an example showing timing transmission of the input signal 306 using the input side timing control signal 115. The microcomputer 1 changes the signal level of the input side timing control signal 115 in advance as an input execution timing 306A when the edge change (High → Low or Low → High) of the target input signal 306 occurs as a serial communication command ( (High → Low or Low → High) is instructed to the input processing IC 3A. The input signal processing circuit 302 incorporated in the input processing IC 3A transmits to the communication I / F circuit 301 that the input execution timing 306A of the target input signal 306 has been detected, and the communication I / F circuit 301 The signal level of the timing control signal 115 is changed.

  In this way, even when it is necessary to change the signal level of the target input signal 306 at a time interval shorter than the time interval that can be transmitted by serial communication, it is necessary to incorporate a timer in the input processing IC 3A. The circuit between the microcomputer 1 and the input processing IC 3A can be simplified.

  FIG. 7 is a timing diagram showing an example of engine control using a timing control signal.

  Assume that control is performed to ignite the engine when the engine rotation angle reaches a certain value. The input data from the engine angle counter changes as shown in the figure. Prior to the ignition ON timing shown in the figure, the microcomputer 1 transmits a command frame having the contents shown in the figure to the output driver IC (for example, the output driver IC 2A) by serial communication. The command, data, etc. 41 of this command frame includes data (“with timing”) indicating that the contents of this command frame are executed after waiting for the timing control signal. The preparation of the contents 41 and the like is performed, and the process waits until the timing control signal is transmitted from the microcomputer 1 (edge change). Preparation for implementation in this example is to set a counter in the output driver IC that calculates a one-shot pulse period based on the pulse period data 41 of commands, data, and the like.

  When the microcomputer 1 determines that the engine rotation angle has reached the ignition ON timing value and transmits the output side timing control signal 114 as the output execution timing 114A (causes an edge change), the output driver IC 2A performs driver control. The signal 220 is transmitted until the counter in the output driver IC that has been set first becomes zero. As a result, the ignition driver signal 222 is turned ON during the pulse period, and engine ignition is performed at a desired timing.

  As described above, the processing content is transmitted from the master device (microcomputer 1) to the slave device (output driver IC 2A, input processing IC 3A, etc.) in advance by serial communication, and only the timing for starting the processing is notified as a timing control signal. Thus, it is possible to avoid the occurrence of processing waiting due to the feature that only one data flows in serial communication at a time. This avoidance of waiting for processing is a feature particularly suitable for control of an internal combustion engine in which many interruptions occur and the execution timing of processing is important.

  In the first embodiment, both the output side timing control signal 114 and the input side timing control signal 115 are provided. However, only one of them may be provided according to the nature of the control. For example, in the case of a control device that frequently generates interrupts on the output side but is unlikely to generate interrupts on the input side, only the output side timing control signal 114 is provided and the input side timing control signal 115 is omitted. Good.

  A second configuration example of the auxiliary identification circuit will be described with reference to FIG.

  The microcomputer 1, serial output signal 111, serial input signal 112, serial clock signal 113, and output driver IC 2A are the same as those described in FIG.

  In the output driver IC 2A, the input signal of the auxiliary identification circuit 204 becomes a Low signal by the pull-down resistor 205 inside the IC because there is no signal connected to the outside of the IC, and the auxiliary identification circuit 204 sets “00” to the communication I / F circuit 201. To communicate.

  In the output driver IC 2B, the input signal of the auxiliary identification circuit 204 becomes the first High signal because the high-level power source 206B is connected to the outside of the IC, and the auxiliary identification circuit 204 sets “01” to the communication I / F circuit 201. To communicate.

  In the output driver IC 2C, the input signal of the auxiliary identification circuit 204 becomes the second High signal because the high-level power source 206C having a voltage level different from that connected to the output driver IC 2B is connected to the outside of the IC. The auxiliary identification circuit 204 transmits “10” to the communication I / F circuit 201.

  For example, a 5V VCC power source can be used as the power source 206B, and a 12V battery power source can be used as the power source 206C. In addition, a 3.3V microcomputer power supply may be used.

  Here, the output driver ICs 2A, 2B, and 2C are taken as an example, but the same auxiliary identification circuit 303 can be configured by the input processing ICs 3A and 3B in FIG.

  With such a configuration, at least two (three in the example of FIG. 8) identically configured ICs can be identified on serial communication using one type of auxiliary identification circuit 204.

  A third configuration example of the auxiliary identification circuit will be described with reference to FIG.

  The microcomputer 1, serial output signal 111, serial input signal 112, and serial clock signal 113 are the same as those described with reference to FIG.

  In the output driver IC 2A, the input signal of the auxiliary identification circuit 204 is a voltage obtained by dividing the voltage of the power source 208 in half by the pull-up resistor 207 and the pull-down resistor 205 inside the IC because there is no signal connected outside the IC. The auxiliary identification circuit 204 transmits “01” to the communication I / F circuit 201 as a Mid signal.

  In the output driver IC 2B, the input signal of the auxiliary identification circuit 204 becomes a High signal because the high-level power source 206 is connected to the outside of the IC, and the auxiliary identification circuit 204 transmits “10” to the communication I / F circuit 201. .

  In the output driver IC 2 </ b> C, the input signal of the auxiliary identification circuit 204 becomes a Low signal because the Low level GND 209 is connected outside the IC, and the auxiliary identification circuit 204 transmits “00” to the communication I / F circuit 201.

  Here, the output driver ICs 2A, 2B, and 2C are taken as an example, but the same auxiliary identification circuit 303 can be configured by the input processing ICs 3A and 3B in FIG.

  With this configuration, up to three identical ICs can be identified on serial communication using one type of auxiliary identification circuit 204.

  A fourth configuration example of the auxiliary identification circuit will be described with reference to FIG.

  In the output driver IC 2A, the input signal of the auxiliary identification circuit 204 is pulled up to the power source 206 by connecting the constant current source 211A outside the IC. The current flowing out of the constant current source 211A flows through a pull-down resistor 205 provided in the output driver IC 2A, and generates a potential difference with respect to the reference GND of the IC. This potential difference is detected by the current detection circuit 210, and the auxiliary identification circuit 204 transmits a digital signal corresponding to the current value to the communication I / F circuit 201.

  The current flowing out of the constant current source 211A and the digital signal output from the auxiliary identification circuit 204 are in a proportional relationship. For example, a preset current threshold value is set such as “1” at 1 mA and “2” at 2 mA. A digital signal can be determined as a reference.

  In this way, at least two identical ICs can be identified on serial communication using one type of auxiliary identification circuit 204.

  A fifth configuration example of the auxiliary identification circuit will be described with reference to FIG.

  In the output driver IC 2A, the input signal of the auxiliary identification circuit 204 is output to an intermediate potential point 212 that becomes a Mid signal that is a voltage obtained by dividing the voltage of the power source 208 by half by a pull-up resistor 207 and a pull-down resistor 205 inside the IC. The auxiliary identification circuit 204 transmits “01” to the communication I / F circuit 201, which is connected inside the IC 2A. The connection between the input signal of the auxiliary identification circuit 204 and the intermediate potential point 212 inside the IC is performed at the time of manufacturing the IC, and the output driver IC 2A is manufactured as an IC fixed to the auxiliary identification “01”.

  In the output driver IC 2B, the input signal of the auxiliary identification circuit 204 is connected inside the output driver IC 2B to a high potential point 213 that becomes a High signal that is the voltage of the power source 208 inside the IC. Is transmitted to the communication I / F circuit 201. The connection between the input signal of the auxiliary identification circuit 204 and the high potential point 213 inside the IC is performed at the time of manufacturing the IC, and the output driver IC 2B is manufactured as an IC fixed to the auxiliary identification “10”.

  In the output driver IC 2C, the input signal of the auxiliary identification circuit 204 is connected inside the output driver IC 2C to a low potential point 214 that is a Low signal that is the GND voltage inside the IC, and the auxiliary identification circuit 204 sets “00”. This is transmitted to the communication I / F circuit 201. The connection of the input signal of the auxiliary identification circuit 204 and the low potential point 214 inside the IC is performed at the time of IC manufacture, and the output driver IC2C is manufactured as an IC fixed to the auxiliary identification “00”.

  Here, the output driver ICs 2A, 2B, and 2C are taken as an example, but the same auxiliary identification circuit 303 can be configured by the input processing ICs 3A and 3B in FIG.

  With this configuration, at least two (three in the example of FIG. 11) identical ICs can be identified on serial communication using one type of auxiliary identification circuit 204.

  A sixth configuration example of the auxiliary identification circuit will be described with reference to FIG.

  The auxiliary identification circuit 204 transmits the auxiliary identification signal to the communication I / F circuit 201 based on the auxiliary identification signal stored in the nonvolatile memory 218 constituted by a flash ROM, EEPROM, or the like.

  In the manufacturing shipment test of the internal combustion engine controller or the output driver IC 2A, the auxiliary identifier setting command is transmitted to the communication I / F circuit 201 through serial communication to the output driver IC 2A, and the output driver IC 2A is When the auxiliary identifier setting mode is set, a predetermined external output pin 216 is connected to the power source 215 to be in a high state, whereby the identification determination circuit 217 determines that the auxiliary identification signal is “1”, and the nonvolatile memory 218 receives and stores this.

  Similarly, in the shipment test at the time of manufacture of the internal combustion engine control device or the shipment test at the time of manufacture of the output driver IC 2B, an auxiliary identifier setting command is transmitted to the communication I / F circuit 201 through serial communication to the output driver IC 2B and output. When the driver IC 2B is set to the auxiliary identifier setting mode, the identification determination circuit 217 determines that the auxiliary identification signal is “0” by connecting the predetermined external output pin 216 to the GND 219 and setting it to the Low state, and is nonvolatile. The sex memory 218 receives and stores it.

  By doing so, the output driver ICs 2A and 2B do not have a dedicated auxiliary identification pin, but change the IC manufacturing process for each auxiliary identification, and thereafter perform management by distinguishing the IC for each auxiliary identification. There is no need to enable auxiliary identification.

  As described above, the auxiliary identification method has been described mainly with respect to the output driver IC. However, as a slave device, auxiliary identification can be performed for the input processing IC, the microcomputer, and other ICs by the same method.

  In each embodiment, examples of input processing ICs and output driver ICs are used as slave side ICs. However, the use of a microcomputer different from the microcomputer that is the master device as the slave side IC results in a lack of functions in the master side microcomputer. Unable to install timer output function, timer input function, digital output function, digital input function, analog output function (D / A converter), analog input function (A / D converter), etc., can be realized with the slave microcomputer. It is also possible to achieve high functionality by installing multiple general-purpose microcomputers with a small number of pins.

  As described above, in the present invention, the microcomputer 1 does not need to have a dedicated signal connection pin for each of various input signals and various output signals, and can transmit signals using three serial communication signals. The number of pins of the microcomputer 1, the output driver ICs 2A and 2B, and the input processing ICs 3A and 3B can be greatly reduced, and a small-sized automobile internal combustion engine control apparatus can be obtained at a low cost. By having the auxiliary identification circuits 204 and 303, even if the same IC is used, it is possible to instruct an IC to be communicated on serial communication, and therefore a chip select signal used to instruct the communication object is also omitted. be able to. In addition, even if a communication wait occurs while the microcomputer 1, the output driver ICs 2A and 2B, and the input processing ICs 3A and 3B are connected by serial communication and communication is performed between other ICs, the command can be executed with a minimum waiting time. Since the frame 11 can be transmitted, the slave identifier 21 and the slave auxiliary identifier 31 are omitted, and there is an advantage that communication can be performed at an appropriate timing as compared with a case where a plurality of consecutive command frames are transmitted to a single IC. is there. These advantages are particularly suitable for an automotive internal combustion engine control apparatus in which the transmission timing of various input signals and various output signals is important for control.

  According to each embodiment described above, conventionally, several tens to hundreds of dedicated communication lines and IC terminals are required for each signal type between the microcomputer and its peripheral driver IC and input processing IC. Since there are a total of four of the three synchronous serial communication lines for transmission signals, reception signals, and clock signals, and the timing control signal lines, the microcomputer and its peripheral driver ICs By using the timing control signal line while significantly reducing the number of pins of the input processing IC and the internal combustion engine control device that does not generate a waiting time for a process in which timing is important even when a large amount of communication occurs can do.

1 Microcomputer 2A, 2B, 2C Output driver IC
3A, 3B input processing IC
11, 1N command frame 21, 2N slave identifier 31, 3N slave auxiliary identifier 41, 4N command, data, etc. 101 CPU
102 ROM
103 RAM
104 A / D converter 105 Timer 106 Serial communication interface 111 Serial output signal 112 Serial input signal 113 Serial clock signal 114 Output side timing control signal 114A Output execution timing 115 Input side timing control signal 201, 301 Communication I / F circuit 202 Timer Circuit 203 Driver circuit 204, 303 Auxiliary identification circuit 205, 304 Pull-down resistor 206, 206B, 206C, 208, 215, 305 Power supply 207 Pull-up resistor 209, 219 GND
210 Current detection circuit 211A Constant current source 212 Intermediate potential point 213 High potential point 214 Low potential point 216 External output pin 217 Identification determination circuit 218 Non-volatile memory 220 Driver control signal 221 Driver signal 222 One-shot pulse period 302 Input signal processing circuit 306 Input signal 306A Input execution timing

Claims (14)

An input signal processing circuit for transmitting an input side signal based on signals from various sensors;
A microcomputer for transmitting an output side signal for controlling the state of the vehicle based on the input side signal;
An output driver circuit for driving various actuators based on the output side signal;
A communication line for connecting the input signal processing circuit, the microcomputer, and the output driver circuit by synchronous serial communication;
A first timing control signal transmitting means provided between the input signal circuit and the microcomputer for transmitting a timing control signal from the input signal processing circuit to the microcomputer; and between the microcomputer and the output driver circuit. An internal combustion engine control device comprising at least one of second timing control signal transmission means provided in the microcomputer for transmitting a timing control signal from the microcomputer to the output driver circuit. The first timing control signal transmission means determines the timing at which the input signal processing circuit transmits the input-side signal when the signal change previously notified from the microcomputer to the input signal processing circuit occurs. Communicate by changing the edge,
2. The internal combustion engine control device according to claim 1, wherein the second timing control signal transmits a timing for executing a command previously notified from the microcomputer to the output driver circuit by changing an edge of the timing control signal. . The input signal processing circuit has at least one input processing IC which is a semiconductor circuit in which an edge detection circuit for sensing a change in signal is integrated,
The output driver circuit has at least one driver IC that is a semiconductor circuit in which a timer circuit for generating a pulse width modulation signal and a pulse signal is integrated,
The communication line is a common first communication line for transmitting a command from the master device to the plurality of slave devices when the microcomputer is a master device and the input processing IC and the driver IC are slave devices, and A plurality of slave devices are configured from a common second communication line for transmitting response data to the command to the master device,
When the master device transmits the command to the slave device, the master device outputs a command frame in which a slave identifier indicating a slave device to be communicated is added to all the commands as destination slave information to the first communication line And
When the slave device receives the command frame from the master device via the first communication line, the command frame is addressed to itself based on the transmission destination slave information included in the command frame. The internal combustion engine control device according to claim 1, wherein the internal combustion engine control device performs processing based on the command in the command frame when it is determined whether or not it is addressed to itself. In preparation for providing two or more of the same type of IC as the slave device,
The IC has an auxiliary identifier,
The internal combustion engine control device according to claim 3, wherein the command frame includes a slave auxiliary identifier corresponding to the auxiliary identifier.   The internal combustion engine control device according to claim 4, wherein the IC includes an auxiliary identification terminal, and the voltage level of the auxiliary identification terminal is used as the auxiliary identifier.   The internal combustion engine control device according to claim 4, wherein the IC includes an auxiliary identification terminal, and the current level of the auxiliary identification terminal is used as the auxiliary identifier. The IC includes a nonvolatile memory,
The internal combustion engine controller according to claim 4, wherein the non-volatile memory stores a voltage level of the auxiliary identification terminal to set an auxiliary identifier of the slave side IC. The IC comprises a ground;
As the voltage level,
A first voltage level pulled down by the ground in the auxiliary identification terminal;
6. The internal combustion engine control device according to claim 5, wherein two of the second voltage levels pulled up by an external power source outside the auxiliary identification terminal are used. The IC comprises a ground;
As the voltage level,
A first voltage level pulled down by the ground in the auxiliary identification terminal;
A second voltage level pulled up by a first external power source outside the auxiliary identification terminal;
6. The internal combustion engine control device according to claim 5, wherein three of the third voltage levels pulled up by a second external power source outside the auxiliary identification terminal are used. The IC includes an internal power supply and a resistor,
As the voltage level,
A first voltage level obtained by the internal power source and the resistor in the auxiliary identification terminal;
A second voltage level that is pulled up by an external power source outside the auxiliary identification terminal and is higher than the first voltage level;
6. The internal combustion engine control device according to claim 5, wherein a third voltage level which is pulled down by an external ground outside the auxiliary identification terminal and is lower than the first voltage level is used. The IC includes an internal power supply, a first resistor, a second resistor, and ground,
The internal power supply and the first resistor, the first resistor and the second resistor, the second resistor and the ground are connected in series, respectively.
As the voltage level,
A first voltage level obtained between the internal power supply and the first resistor;
A second voltage level obtained between the first resistor and the second resistor;
6. The internal combustion engine controller according to claim 5, wherein three of the third voltage levels obtained between the second resistance and the ground are used. A first IC that performs a first function in the control of an internal combustion engine for automobiles;
A second IC for performing a second function in the control of an internal combustion engine for automobiles;
A microcomputer for performing serial communication with the first and second ICs;
The microcomputer is
Transmitting in advance the first data necessary for executing the first function to the first IC;
Transmitting in advance the second data necessary for executing the second function to the second IC;
Independently of the transmission of the first and second data,
A first signal for instructing the first IC to execute the first function, or
Of the second signals that instruct the second IC to execute the second function,
An internal combustion engine control device that transmits at least one of them. The first function indicates a function of transmitting input signals from various sensors to the microcomputer,
The second function indicates a function of driving various actuators by an output signal from the microcomputer.
The internal combustion engine control device according to claim 12. The first data indicates data input from various sensors,
The second data indicates data for driving various actuators.
The internal combustion engine control device according to claim 12.

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