JP2001168889A - Electronic control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in electronic control (ECU) by which a response time from the input of interrogation data to the output of response data is shortened and communication with another electronic control is normally executed. SOLUTION: This ECU 1 consists of a controller 10, having microcomputers 12 and 14 capable of mutual communication and communication equipment 30 having communication ICs 32 and 34. The ICs 32 and 34 are respectively connected to the microcomputers 12 and 14. Then the microcomputers 12 and 14 individually and directly input interrogation data which is transmitted to the ECU 1 via a bus 9. In the ECU 1, a time for inputting the interrogation data to the microcomputer 14 is shorter than that in the conventional ECU 1, which is provided with the communication IC only in the microcomputer 12. Then the response time necessary for outputting the response data responding to the interrogation data is shortened, and also communication is executed via another communication IC eve when one communication IC is in trouble, so that communication can be normally executed with another ECU 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-vehicle device for individually executing pre-assigned control, performing communication via a vehicle LAN wired in a vehicle, and transmitting and receiving various data.

[0002]

2. Description of the Related Art Conventionally, a vehicle has been equipped with a water temperature sensor 152 for the purpose of reducing wire harnesses and standardizing equipment.
And a data acquisition device for acquiring various data, such as a wheel speed sensor, which is divided into several units, and for each of the divided data acquisition devices 150, a control including a computer for performing a process for controlling a vehicle. Device 110;
An ECU (Electronic Control System), which is an in-vehicle device including a communication device 130 for communicating data.
Unit 100), and a bus 10 wired in the vehicle so that the ECUs 100 can communicate with each other.
9 to construct a vehicle LAN (local area network).

[0003] In the vehicle in which the vehicle LAN is constructed, each ECU 100 is set to execute various pre-assigned controls such as engine control and transmission control. EC
It communicates with U100 to input and output necessary data.

[0004] In recent years, vehicles have been required to perform technically advanced and complicated controls such as improvement of fuel efficiency and reduction of carbon dioxide in exhaust gas. Therefore, the control device 110 of each ECU 100 is required to be able to execute such complicated and sophisticated control. However, on the other hand, the control device 11
It is also required to reduce the production cost of zero. Under these circumstances, the control device 110 is a combination of a plurality of low-priced microcomputers (hereinafter referred to as “microcomputers”) that are inferior in performance such as processing speed as compared to the latest microcomputers.

[0005] Specifically, this control device 110 is shown in FIG.
As shown in FIG. 8, a main microcomputer 112 connected to the communication device 130, and a plurality of sub-microcomputers 114 (only one is shown in FIG. 8) connected to the main microcomputer 112 via a communication line α, Each microcomputer 112, 114
Are configured to be capable of internal communication by SPI (Serial Peripheral Interface) communication.

The microcomputers 11 of the control device 110
2 and 114, the control assigned to each of the ECUs 100 is further finely assigned. For example, in the case of the ECU 100E that performs engine control, the main microcomputer 112 performs injection and ignition control, and the sub microcomputer 114 controls the throttle opening. Done.

[0007] In order to perform such control by each of the microcomputers 112 and 114, each of the data acquisition devices 150 is connected according to the shared control. In the data acquisition device 150, in the case of the ECU 100E, a water temperature sensor 152 and the like are connected to the main microcomputer 112 that performs injection and ignition control, and a throttle sensor 156 and the like are connected to the sub-microcomputer 114 that performs control related to throttle opening.
The detection circuit 154 for detecting the engine speed is connected to both the microcomputers 112 and 114 because of the speed at which the microcomputers 112 and 114 acquire data.

In the ECU 100 configured as described above, when receiving data, first, the communication device 130 receives the data. Then, the data is transferred to the main microcomputer 1
12 is input from the communication device 130 and further transferred to the sub-microcomputer 114. On the other hand, in this ECU 100,
When transmitting data, data to be transmitted is prepared by each of the microcomputers 112 and 114.
Then, the data prepared by the sub-microcomputer 114 is transmitted to the main microcomputer 112. Then, the main microcomputer 112 converts the prepared data into data adapted for communication via the bus 109, and transmits the converted data via the communication device 130.

Specifically, for example, when the ECU 100T performing the transmission control needs data on the water temperature and the throttle opening, as shown in FIG. Is output to the ECU 100E which handles the data of (1). Then, in the ECU 100E, first, the main microcomputer 112 inputs the question data via the communication device 130, and further transfers the question data to the sub-microcomputer 114. The sub microcomputer 114 prepares throttle opening data and the like, and the data and the like are stored in the main microcomputer 11.
2, the main microcomputer 112 prepares water temperature data and the like. Then, the main microcomputer 112
Based on these water temperature data and throttle opening data,
Response data that is data that responds to the question data is created, and the response data is output via the communication device 130 to the ECU 100T that is the transmission source of the question data.

In this system, recently, a CAN (Controller Area Network) protocol of Bosch Germany has been widely used as a protocol for a vehicle LAN.

[0011]

However, the above-mentioned EC
In U100, when data received by the communication device 130 is input to the sub-microcomputer 114, the main microcomputer 112
Had to be transferred to the Internet, which took time for the transfer. In particular, when the communication device 130 receives data, if the main microcomputer 112 is in a so-called busy state in which data cannot be input by performing some processing, it takes more time to input. Therefore, in the conventional ECU 100, the response time from the reception of the question data to the transmission of the response data becomes extremely long, and the number of controls that can be performed per unit time in the entire vehicle LAN is reduced. There is a problem that the control becomes slow.

For example, in a vehicular LAN using the CAN protocol, it is possible to connect a tester to the bus 109, output question data to each module, and obtain response data. In general, the tester determines that an error occurs when the time from when the question data is output to the ECU 100 to when the response data is input exceeds 50 ms. Therefore, if the response time is long as described above, the tester cannot acquire data. Failed.

In the ECU 100, the communication device 1
Since communication is performed only in the ECU 30, the ECU 100 has a problem that the communication becomes impossible if the communication device 130 breaks down. Therefore, an object of the present invention is to provide an in-vehicle device that has a short response time and can always communicate with another in-vehicle device.

[0014]

According to a first aspect of the present invention, there is provided an on-vehicle apparatus in which a communication device connected to a main data processing means corresponding to a main microcomputer is used as a main communication device, and a sub-microcomputer is used as a communication device. For each corresponding sub-data processing means, a sub-communication means is provided for the sub-data processing means to communicate with another device via the bus, and the sub-data processing means transmits data destined for the vehicle-mounted device via the sub-communication means. It is characterized by receiving.

In the vehicle-mounted device according to the first aspect, the main data processing means and the sub-data processing means transmit the data addressed to the vehicle-mounted device including the above-mentioned question data sent to the vehicle-mounted device via the vehicle LAN. Are directly input individually through the main communication device and the sub communication device provided for each. In other words, the sub-data processing means can directly acquire the data destined for the on-vehicle device without passing through the main data processing means unlike the conventional device.

In the vehicle-mounted device according to the first aspect,
Since there is no need to transfer data destined for the in-vehicle device from the main data processing unit to the sub data processing unit, the amount of communication between the main data processing unit and the sub data processing unit is reduced. Therefore, when the in-vehicle device according to claim 1 is used, the time from input of the question data to the output of the response data for the time required for the transfer from the main data processing means to the sub data processing means in the related art is obtained. Response time can be shortened. In addition, when this in-vehicle device is used, the amount of communication between the main data processing means and the sub data processing means is reduced, so that there is no need to perform communication processing between the two data processing means, so that many types of control are performed. Can be performed by each data processing means, and the vehicle LAN
As a whole, the number of controls that can be performed per unit time increases, and quick control can be performed as a whole.

Next, the on-vehicle apparatus according to the second aspect of the present invention includes a communication determining means for determining whether communication by the main communication means and the sub-communication means is possible, and the communication determining means determines that communication is impossible. The main data processing means or the sub data processing means corresponding to the main communication means or the sub communication means communicates via the main data processing means or the sub data processing means corresponding to the main communication means or the sub communication means.

In the vehicle-mounted device according to the second aspect, when communication by any of the main and sub-communication means is impossible, communication is performed via another communication means. It is prevented from becoming disabled. Therefore, this claim 2
The use of the in-vehicle device described above can reliably prevent interruption of communication with another in-vehicle device, and can improve the reliability of control performed jointly with another in-vehicle device.

By the way, in the above-mentioned vehicle-mounted device, when communication by the main data processing means is disabled, the data prepared by the sub data processing means is once transmitted to the main data processing means, and The response data created by the main data processing means is transmitted to the communicable sub data processing means and transmitted to the vehicle LAN. This is because the process of creating the response data has to perform various processes such as a process of attaching various codes such as an error correction code, and the transmission program for executing the processes is stored. This is because a large storage capacity is required to perform such operations, and if a program requiring such a large storage capacity is incorporated in the sub-data processing means, the types of control that can be performed by the sub-data processing means are reduced.

However, if there is sufficient capacity for storing the program of the sub-data processing means, the communication determining means determines that the communication is not possible, as in the vehicle-mounted device according to claim 3. In place of the main data processing unit, one of the sub data processing units is switched to execute the response process, and the main data processing unit is executed by another sub data processing unit that can communicate with the sub communication unit. It may be.

With this configuration, when the communication by the main communication unit is disabled, the response processing is performed by the sub data processing unit, so that the response data is created. Response data can be output quickly.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the control device described above will be described below. Here, FIG. 1 is a block diagram for explaining an ECU (Electronic Control Unit), which is an in-vehicle device of the present embodiment, and a connection relationship between this ECU and another ECU. FIG. 6 is an explanatory diagram for explaining data transmitted and received between the ECUs according to the present embodiment.

As shown in FIG. 1, the ECU 1 of this embodiment comprises a control device 10 for controlling the engine and another ECU 1
And a communication device 30 for performing communication. The control device 10 includes two microcomputers 12, 1
4 (hereinafter, referred to as "microcomputers 12 and 14"), and the microcomputers 12 and 14 can communicate with each other via a communication line α of a SPI (serial peripheral interface) system. And in this control device 10,
The microcomputers 12 and 14 share control of engine control, the main microcomputer 12 performs processing related to fuel injection control and ignition plug ignition control, and the sub-microcomputer 14 performs processing related to throttle drive control. I have. In addition, each of the microcomputers 12 and 14 performs a communication determination process of determining whether data can be transmitted and received using the communication device 30 described later.

The control device 10 of the ECU 1 includes:
A plurality of data output devices 50 for acquiring data required for engine control are connected. Specifically, the control device 10 includes a data output device 50 such as a water temperature sensor 52, an engine speed detection circuit 54, and a throttle sensor 56.
Is connected, and the water temperature sensor 52 is connected to the main microcomputer 12.
The throttle sensor 56 is connected to the sub microcomputer 14, and the engine speed detection circuit 54 is connected to both the microcomputers 12 and 14.

The microcomputers 12 and 14 of this embodiment correspond to the main data processing means and the sub data processing means of the present invention, respectively. Each of the microcomputers 12 and 14 respectively
It is a known microcomputer including a CPU, a ROM, and a RAM. Next, the communication device 30 includes two well-known communication ICs 32 and 34 (Intel: 82527) used for a vehicle LAN using the CAN protocol.
The communication ICs 32 and 34 are connected to the microcomputers 12 and 14, respectively. Hereinafter, the communication IC 32 connected to the main microcomputer 12 is referred to as a main communication IC 32, and the communication IC 34 connected to the sub-microcomputer 14 is referred to as a sub-communication IC 34.

The communication ICs 32 and 34 are connected to a vehicle LAN bus 9 wired in the vehicle, respectively.
It is configured to be able to communicate freely with a communication device of another ECU 1 connected to the bus 9. Note that the communication I
C32 and C34 correspond to the main communication unit and the sub communication unit of the present invention, respectively.

On the other hand, as shown in FIG. 1, many ECUs 1 including an ECU 1T for controlling a transmission are connected to a bus 9 to which the ECU 1 of this embodiment is connected. Is connected freely. Each of the ECUs connected to the bus 9 is connected to various data acquisition devices such as wheel speed sensors that output data necessary for control by each ECU, similarly to the ECU 1 described above. Each ECU 1 is the ECU 1 of the present embodiment.
The microcomputer may be provided with two microcomputers, may be provided with only one, or may be provided with three or more microcomputers.

When each of the ECUs 1 configured as described above receives the question data, it transmits response data in response to the question data. For example, when the ECU 1 transmits the question data to the ECU 1, as shown in FIG. Response data consisting of data such as water temperature, throttle opening, engine speed, etc. is transmitted to the EC which performs transmission control.
When the U1T receives the question data, response data including data indicating the speeds of all the wheels of the vehicle and the like is transmitted as shown in FIG. Note that “ID” in FIG.
This is a code representing an answer format in which what data is included in the response data is determined in advance. That is, the data of ID10 includes data including water temperature, throttle opening, engine speed, and the like.

The bus 9 is a vehicle LA mounted on a vehicle.
Although a CAN (Controller Area Network) protocol is applied to N, since the CAN protocol is well known, a detailed description thereof will be omitted in this embodiment. Hereinafter, an operation of control device 10 when data addressed to ECU 1 is received from another ECU will be described. In the following description, a case will be mainly described where the ECU 1E of the present embodiment that performs engine control receives question data as data addressed to the ECU 1E.
The data addressed to the ECU 1E corresponds to the data addressed to the vehicle-mounted device of the present invention.

FIG. 2 and FIG. 3 are schematic diagrams for explaining data transfer. First, the ECU of the present embodiment
1, when receiving the question data, each microcomputer 12, 1
4 includes communication ICs 32 and 34, respectively.
As shown in FIG. 2A, the communication ICs 32 and 34 respectively receive the question data, and the microcomputers 12 and 14 respectively input the question data received by the communication ICs 32 and 34.

The mode of requesting the output (Mode) 01 and the ID 02 indicating the answer format are attached to the question data as information, so that the communication ICs 32 and 34
It is determined whether or not the mode attached to the question data is a mode in which response data is to be output from the ECU 1. If the mode is to output response data, the question data is received. Next, each of the microcomputers 12 and 14 has a communication IC 3
The data corresponding to ID02 of the question data received by the communication devices 2 and 34 is prepared. At this time, the sub-microcomputer 14 prepares data D14 (for example, data indicating the throttle opening) and stores the data D14 together with a mode 41 representing a mode responding to the mode 01 and an answer format ID02.
As shown in FIG. 2B, the data is transmitted to the main microcomputer 12 by SPI communication. The data transmitted by the SPI communication is stored in the RAM in the main microcomputer 12. On the other hand, the response format I
Data D14 (for example, data indicating water temperature) corresponding to D02 is prepared, and the data D14 is stored in the RAM. When all the data corresponding to ID02 is stored in the RAM of the main microcomputer 12, the main microcomputer 12 creates response data from the data and queries the response data as shown in FIG. It is sending to the source of the data.

As shown in FIG. 3A, when question data of ID03 for which data can be prepared only by the main microcomputer 12 is input by each of the microcomputers 12 and 14, data is not prepared by the sub-microcomputer 14. Therefore, data communication to the main microcomputer 12 is not performed, and response data is created only from data D12 and D16 (for example, data indicating water temperature and engine rotation) prepared by the sub-microcomputer 14, and FIG. ), The response data is transmitted to the ECU 1 that transmitted the question data.

On the other hand, the ECU 1 of this embodiment is replaced by another ECU.
1 is sent to the ECU 1 and the response data is sent to the ECU 1
When the data is received as data addressed to E, the response data is input to each of the microcomputers 12 and 14, respectively.
Each of the microcomputers 12 and 14 obtains data necessary for each control from the input response data (for example, data indicating the speed of each wheel, data indicating the input stage of the gear, etc.).

Next, the detour communication processing (S1, S3) performed when the main microcomputer 12 determines that communication with the communication IC 32 is impossible will be described. here,
FIG. 4 is a flowchart of the bypass communication process (S1) performed by the main microcomputer 12, and FIG. 5 is a flowchart of the bypass communication process (S3) performed by the sub-microcomputer 14.

This detour communication processing (S1) is repeatedly executed when the vehicle is turned on. First, in the detour communication process (S1), a communication determination process is performed to determine whether communication via the communication IC 32 is possible (S1).
0). When an affirmative determination is made in this determination (S10), normal processing (S12) is performed, for example, question data,
Response data corresponding to the question data output from the main microcomputer 12 (for example, data relating to the speed of the wheels) and the like are used as data addressed to the ECU 1E of the present embodiment and the main communication IC 32.
If the data is received, the data addressed to the ECU 1E is input and various processing is performed. If there is data such as response data to be transmitted to another ECU 1, the data is transmitted to the communication IC 32.
Is output and transmitted. Then, when this processing (S12) ends, the detour communication processing (S1) ends.

In the communication determination process (S10), each of the communication ICs 32 and 34 has a well-known self-determination function for determining whether or not communication is possible. , 34 determine that communication is not possible or possible, a signal indicating that communication is not possible or possible is sent from each communication IC 32, 34 to each microcomputer 12, 14 directly connected to each communication IC 32, 34. The microcomputers 12 and 14 perform a process of determining whether a signal indicating that communication is not possible or possible from the communication ICs 32 and 34 has been input.

On the other hand, if a negative determination is made in S10, the main microcomputer 12 transmits to the sub-microcomputer 14 communication-disabled data indicating that communication has been disabled via the SPI communication (S20). As shown in FIG. 6C, the communication-disabled data may be transmitted as part of data (for example, water temperature data) communicated from the main microcomputer 12 to the sub-microcomputer 14 via the SPI communication.

Next, when S20 is completed, a setting is made so that data to be input / output to / from another ECU 1 is input / output via the sub-microcomputer 14.
Then, when there is data to be transmitted to another ECU 1, an output process of outputting the data to the sub-microcomputer 14 is performed. On the other hand, the sub-microcomputer 14 which has received the data addressed to the ECU 1E from the other ECU 1 converts the data. If there is a request to transfer the data to the main microcomputer 12, an input process for inputting the data from the sub-microcomputer 14 is performed (S22). When this processing (S22) ends, next,
A determination is made as to whether or not communication has been restored (S24). If the determination is affirmative, a signal for communication recovery is output to the sub-microcomputer 14 (S26), the determination in S10 is performed again, and a negative determination is made. If it has, the determination in S22 is made.

Next, a detour communication process (S3) performed by the sub-microcomputer 14 when a negative determination is made in the process of S10 of the main microcomputer 12 will be described. The detour communication processing (S3) performed by the sub-microcomputer 14 is also repeatedly executed after the power of the vehicle is turned on. First, in the bypass communication processing (S3) of the sub-microcomputer 14, the communication IC 32
Then, it is determined whether or not communication disabled data indicating that the communication in the above is impossible is transmitted from the main microcomputer 12 via the SPI communication (S30).

If a negative determination is made in this determination (S30), the process (S3) ends, and if an affirmative determination is made, it is determined whether the sub-communication IC 34 has received data addressed to the ECU 1E. Alternatively, a data reception determination is made to determine whether data to be transmitted from the main microcomputer 12 to the outside has been input from the main microcomputer 12 (S32).
When a negative determination is made in this determination (S32), the present process (S3) ends. On the other hand, when an affirmative determination is made in this determination (S32), the ECU
1E, and outputs a signal requesting transfer to the main microcomputer 12 and outputs the data. Alternatively, the data transferred from the main microcomputer 12 to be transmitted to the outside is transmitted to the sub-communication device. A transfer process of outputting to the IC 34 for transmission is performed (S34), and the process (S3) is completed.

Here, the data transferred from the sub-microcomputer 14 to the main microcomputer 12 is necessary for the processing by the main microcomputer 12 in addition to the data representing the received wheel speed as shown in FIG. Such data (such as data indicating the throttle opening) may be added and transferred.

The bypass communication process (S1) performed by the main microcomputer 12 may be performed by the sub-microcomputer 14, and the bypass communication process (S3) performed by the sub-microcomputer 14 may be performed by the main microcomputer 12. . When such detour communication processing (S1, S3) is performed, as shown in FIG. 7, when communication via the main communication IC 32 is disabled and communication is performed bypassing the sub communication IC 34, the ECU 1E When the sub-communication IC 34 receives question data as the above data, the question data is first transmitted from the sub-microcomputer 14 to the main microcomputer 12, and each microcomputer 12, 14 prepares data corresponding to the question data. The data prepared by the sub-microcomputer 14 is transmitted to the main microcomputer 12, and the main microcomputer 12 creates response data.
The response data is transmitted to the sub microcomputer 14. Then, response data is output from the sub microcomputer 14.

When communication via the sub-communication IC 34 is not possible, when question data is input to the main microcomputer 12 as in a conventional ECU, the question data is output to the sub-microcomputer 14, and the conventional The same operation as that of the ECU is performed, and response data is output.

Using the engine control module configured as described above has the following effects. In the ECU 1 of this embodiment, the main microcomputer 12 and the sub microcomputer 1
Numeral 4 directly inputs data addressed to the ECU 1E including the question data, which is sent to the ECU 1 via the bus 9, individually via the main communication IC 32 and the sub communication IC 34 provided respectively. That is, the sub-microcomputer 14 can directly acquire data addressed to the ECU 1E without the intervention of the main microcomputer 12 as in the conventional device.

In the ECU 1 of this embodiment, the EC
Since there is no need to transfer data addressed to U1E from the main microcomputer 12 to the sub-microcomputer 14, the main microcomputer 12
The communication amount between the sub microcomputer 14 and the sub microcomputer 14 is reduced. Therefore, when the ECU 1 of this embodiment is used, the conventional main microcomputer 12
The response time from the input of the question data to the output of the response data can be shortened by the time required for the transfer to the sub-microcomputer 14. Also, since the amount of communication between the main microcomputer 12 and the sub-microcomputer 14 is reduced, many types of control are performed by each microcomputer 1 as much as there is no need to perform communication processing between the two microcomputers 12 and 14.
2 and 14, the number of controls that can be performed per unit time increases in the entire vehicle LAN, and quick control can be performed as a whole.

Next, the ECU 1 of this embodiment is provided with the main communication I
A communication determination process (S10) for determining whether communication by the C32 and the sub-communication IC 34 is possible is performed, and the main communication I that is determined to be incommunicable in the communication determination process (S10).
The main microcomputer 12 or the sub-microcomputer 14 corresponding to the C32 or the sub-communication IC 34
The communication is performed via the main microcomputer 12 or the sub microcomputer 14 corresponding to the second or sub communication IC 34.

That is, in the ECU 1 of this embodiment, when communication is not possible with any of the main and sub communication ICs 32 and 34, communication is performed via the other communication ICs 32 and 34. It is possible to prevent communication from being disabled. Therefore, when the ECU 1 of this embodiment is used, other E
The communication with the CU 1 can be reliably prevented from being interrupted, and the reliability of control performed in cooperation with another ECU 1 can be improved.

Incidentally, in the ECU 1 of this embodiment, FIG.
As shown in (1), when the communication with the main microcomputer 12 is disabled, the question data and the data prepared by the sub-microcomputer 14 are transmitted to the main microcomputer 12 once, and the response data created by the main microcomputer 12 is transmitted. Is transmitted to the communicable sub-microcomputer 14 and transmitted to the bus 9.
This is because the process of creating the response data has to perform various processes such as a process of attaching various codes such as an error correction code, and the transmission program for executing the processes is stored. This is because a large storage capacity is required to perform such operations, and if a program requiring such a large storage capacity is incorporated in the sub-microcomputer 14, the types of control that can be performed by the sub-microcomputer 14 are reduced.

However, if the capacity of the sub-microcomputer 14 to store the program or the like is sufficient, if it is determined that communication is not possible, a response is sent to any of the sub-microcomputers 14 instead of the main microcomputer 12. The processing may be switched to be executed, and the processing of creating response data performed by the main microcomputer 12 may be executed by another sub-microcomputer 14 capable of communicating with the sub-communication IC 34.

In this case, since the response processing is performed by the sub-microcomputer 14, the response data is created, so that the response data can be output more quickly than in the case where the response data is transmitted through the main microcomputer 12.

[Brief description of the drawings]

FIG. 1 is a schematic circuit diagram of an engine module and peripheral devices of the present embodiment.

FIG. 2 is an explanatory diagram for explaining transmission and reception of data in the embodiment.

FIG. 3 is an explanatory diagram for explaining exchange of data in the present embodiment.

FIG. 4 is a flowchart of processing when communication is disabled according to the embodiment.

FIG. 5 is a flowchart of processing when communication is disabled according to the embodiment.

FIG. 6 is an explanatory diagram of data transmitted in the communication determination processing of the embodiment.

FIG. 7 is an explanatory diagram for explaining exchange of data in the present embodiment.

FIG. 8 is a schematic circuit diagram of a conventional engine control module and peripheral devices.

FIG. 9 is an explanatory diagram for explaining data transmission and reception in a conventional engine control module.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... ECU, 9 ... Bus, 10 ... Control device, 12 ... Main microcomputer, 14 ... Sub microcomputer, 30 ... Communication device, 32
... Main communication IC, 34 ... Sub communication IC, 50 ... Data output device, 52 ... Water temperature sensor, 54 ... Engine speed detection circuit, 56 ... Throttle sensor

Claims (3)

[Claims] 1. A main communication device for communicating with another device connected to a bus via a vehicle LAN bus wired in a vehicle, and an inquiry from the other device via the main communication device. When receiving the data, create response data to the question data,
Main data processing means for executing at least a response process of transmitting the response data to the transmission source of the question data via the main communication means; and communication with the main data processing means without interposing the main communication means. And one or more sub-data processing means for executing various processes by sharing with the main data processing means, wherein the sub-data processing means is connected to the bus for each of the sub-data processing means. An in-vehicle device, provided with a sub-communication unit for performing communication with the other device via the sub-communication unit, wherein the sub-data processing unit receives the data addressed to the in-vehicle device via the sub-communication unit. 2. The in-vehicle device according to claim 1, further comprising: a communication determination unit that determines whether communication by the main communication unit and the sub communication unit is possible, wherein the communication determination unit determines that communication is not possible. The main data processing means or sub data processing means corresponding to the determined main communication means or sub communication means communicates via the main data processing means or sub data processing means corresponding to the main communication means or sub communication means. A vehicle-mounted device characterized by the above-mentioned. 3. The in-vehicle device according to claim 1, wherein: a communication determining unit that determines whether communication by the main communication unit is possible; and if the communication determining unit determines that communication is not possible. An in-vehicle apparatus comprising, in place of the main data processing means, one of the sub data processing means including a switching means for executing the response processing.