JP3383462B2 - Multiplex transmission system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiplex transmission system including a plurality of multiplex communication nodes for controlling a plurality of electrical equipment units, and more particularly to a multiplex transmission system for improving system reliability in the event of a communication node failure. Is.

[0002]

2. Description of the Related Art In recent years, in order to eliminate the enlargement and complication of wiring (wire harness) that connects the electric component units with the increase in the number of electronic parts (electric component units) of automobiles, it has been provided in a plurality of electric component units. Attention has been paid to multiplex communication in which a communication node is connected to a common multiplex communication line, and signal transmission between each electrical unit is performed by the communication node.

In the multiplex communication system constructed by connecting a plurality of communication nodes for sending or receiving digital information or for sending and receiving digital information, each communication node sends the communication information to a communication line. The digital information captured by the communication node designated in advance forms a data frame of a certain length, for example, in order to facilitate its handling. This data frame is called a communication frame and is a group of code data having a predetermined number of bits and a total data length according to a preset data format.

FIG. 1 shows a format of a communication frame adopted in a conventional vehicle multiplex transmission system.
In FIG. 1, frame F is SD (Start Delimiter).
) A frame structure having a code, a priority code, a frame ID code, a data length, data 1 to data N, and a check code.

First, the "SD code" is a specific code indicating the start of the frame F, and the receiving multiplex node uses this S code.
When the D code code is received, the start of the frame F is recognized. The “priority code” is a code indicating a priority order that indicates which signal should be preferentially processed when a plurality of multiple nodes simultaneously transmit data and the signals collide. In this embodiment, the lower the bit value, the higher the priority is assigned. This is because the low level is WIRED-OR on the bus. If signals are sent from multiple nodes at the same time, the “priority code” of the node with the higher priority remains on the bus, and the lower priority node changes its own “priority code” to another code. Therefore, the data collision is detected. And
By delaying the retransmission of its own failed frame, the retransmission from the node with a high priority is prioritized.

The "frame ID code" is a code indicating the transmission destination of the frame, and if N types of communication nodes are provided, areas from ID0 to IDN are set. The transmission source node writes the transmission destination ID in the frame and transmits the frame. Further, the receiving node stores the ID of the frame to be received by the node as a memory map, and only when the ID code of the received frame matches the ID registered in the own node, the reception frame capturing process is performed. To execute.

In the "data length", the number of data that follows is written, and if there are N data, N is sent as the data length. The multi-node which receives this frame reads the data of the data length. The field following the data is a CRC check code (error detection code), and by confirming this, it can be known that the end of the frame.

The ACK field is where ACK signals from other nodes (N nodes are planned for the entire system) are inserted. This ACK signal is not returned to the source node if the receiving node does not receive the data correctly, and the multiple node on the transmission side determines whether the returned frame includes the ACK signal. By determining whether or not the frame transmission to the transmission destination has failed, if the frame transmission fails, the same frame is retransmitted.

FIG. 2 shows an example of the circuit configuration of the communication node. As shown, for example, ABS controller (Anti
-lock-brakesystem) is the communication IC
High speed transmission line MB1 and medium and low speed transmission line MB via 101
Connected to 2. Reference numeral 100 denotes a control CPU, which operates according to a program stored in the RAM / ROM 102. The communication IC 101 controls the physical layer level protocol of the CSMA / CD system. Further, the communication IC 101 stores the ID code of the frame to be received by its own node, and outputs the received data to the CPU 100 when the IDs of the received frames match. On the other hand, if the IDs do not match, the ACK signal indicating only the reception at the communication IC is sent to the frame without being output to the CPU. The CPU 100 receives a signal from an input auxiliary device 104 such as various sensors and switches via the input interface (I / F) unit 103, and receives the frame data received via the output interface (I / F) unit 105. A control signal is output to the output auxiliary device 106 such as a solenoid valve drive motor based on the above.

Further, the CPU 100 is a communication IC 101.
Control, the signal input from the input auxiliary device 104 is written in a communication frame as data, and is sent to the multiplex transmission path MB1 or MB2 via the communication IC, and at the same time, the communication IC1
01 receives the data from the other node and processes it as a control signal, and outputs it to the output auxiliary device 106. That is, CPU
Reference numeral 100 designates the frame data on the bus as the electrical unit 10
4 converts the data into a usable format, or converts the data from the electrical component unit 104 into a predetermined frame format. The other important role of CPU100 is AC
Management of K data. That is, as described above, in the communication system of the present embodiment, all nodes (communication IC 101 of the nodes)
When it receives frame data from another node without error, it returns an ACK bit to the node that sent it. Therefore, by checking the contents of this ACK field, it is possible to know which node could not receive the frame transmitted by itself. The CPU 100 is in charge of this check work. this is,
This is because the communication IC 101 is limited to communication control, and the CPU 100 performs high-level data processing.

The input signal from the input auxiliary device 104 is sent from the input interface (I / F) unit 103 to the input auxiliary device failure detection circuit unit 107. The input auxiliary device failure detection circuit unit 107 detects the failure of the input auxiliary device 104 by detecting the voltage level of the input signal from the input auxiliary device 104 and sends the failure detection signal to the CPU 100. On the other hand, the control signal output from the CPU 100 is an output driver 109 (IPS: intelligent po) with a diagnostic function.
wer switching) to the output auxiliary device 106. The IPS 109 diagnoses whether the control signal sent from the CPU 100 is normal.

The CPU 100 and communication IC 10 described above
1, the input and output I / F units 103 and 105, and the input auxiliary device failure detection circuit unit 107 are connected to the external battery power supply path B via the power supply circuit unit 108 (also the node supplied with power via the ignition switch). Yes) power is being supplied. The power supply circuit unit 108 is connected to the power supply path B, regulates the drive voltage for the communication node (for example, + 5V), and then supplies power to each circuit inside the communication node.

Further, in the conventional multiplex transmission system, two types of communication lines are provided, which can communicate by turning on the ignition switch (for convenience, referred to as a high-speed transmission line) and a battery power source for continuous communication. It is roughly classified into a possible one (for convenience, referred to as a medium-low speed transmission line).
In the communication node connected to these two types of multiplex transmission lines, the communication node connected to the high-speed transmission line is a communication node that controls engine control and ABS control.
The processing speed and memory capacity of are set to a large value.
On the other hand, the communication node connected to the medium / low speed transmission line is a communication node that controls the operation of the wiper and various lamps, and
In some cases, the calculation processing speed and memory capacity of the PU are set low, and in some cases, a CPU is not mounted and communication frames are transmitted and received via a communication IC.

In the multiplex transmission system including the communication nodes described above, as a conventional technique regarding a countermeasure against a failure of the communication node, for example, when an instrument panel node fails, a hazard as a control target auxiliary device of the instrument panel node Since the lamp does not light up, the driver is notified of the failure. At this time, if the driver operates the turn lamp operation lever in a predetermined sequence to display the hazard lamp as a substitute for the turn lamp, the driver determines that the substitute control is performed. When this judgment is made, the front node and the rear node blink the turn lamps on the left, right, front, and rear to make them in a hazard state. in this way,
It has been proposed that another node substitutes the control target auxiliary device of the faulty node (Japanese Patent Application No. 5-337819).
issue).

As another conventional technique, when the meter information cannot be displayed by the meter node due to a failure of the meter display device or the like, the state is detected and the CRT of the CRT display node for the in-vehicle device is detected. Japanese Patent Laid-Open No. 6-27910 proposes a display of the meter information.

[0016]

However, in the conventional multiplex transmission system which takes measures against the above-mentioned communication node failure, in the former prior art, first, it is necessary to inform the driver of the failure of the instrument panel node. There is, but it can be notified by not lighting with auxiliary devices that light hazard lamps, etc., for example, 4WS, ABS or the node that controls them has failed, the meter node that controls the warning lamp that notifies the failure has failed Assuming a case, the driver cannot be notified of the failure. In addition, the driver who has been notified of the node failure needs to remember the special operation of the auxiliary device for which the alternative control is to be executed. It will be done by referring to it, which may be very troublesome.

Further, the latter prior art is limited to a vehicle equipped with a CRT for operation display of an in-vehicle device such as a car navigation system and needs to be retrofitted to a vehicle not equipped with a CRT. However, there is a problem that the total product price of the car will increase. Therefore, the present invention was proposed in order to solve the above-mentioned problems of the prior art, and the object is to:
The operation of informing the driver by substituting the function of a failed communication node for another communication node is performed without bothering the driver and without the need for additional parts to increase costs. We are currently proposing a multiplex transmission system that can improve the reliability of the entire system.

[0018]

[Means for Solving the Problems] and

In order to solve the above problems and achieve the object, the multiplex transmission system of the present invention has the following configuration. That is, a first node that controls the first output auxiliary device, a second node that controls the second output auxiliary device, and a third output based on the control data sent from the second node. A multiplex transmission system in which a third node for controlling an auxiliary device is connected to a common communication line, and the first node has a failure detecting means for detecting whether or not the third node has failed. And when a failure of the third node is detected, the second node
Means for changing the address of its own node so as to be able to receive the control data in which the address of the third node has been written, which is transmitted from the second node, and based on the control data received from the second node, And a means for controlling one output auxiliary device.

A first node for inputting a signal from the first input auxiliary device and first control data based on the signal from the first input auxiliary device sent from the first node are transmitted. Upon reception, the third control is performed based on the first control data.
A second node for sending the second control data to the node and a third node for controlling the third output auxiliary device based on the second control data are connected on a common communication line. In the transmission system, the third node detects a failure in the second node, and the first node detects a failure in the second node.
Means for changing the address of its own node so that it can receive the first control data in which the address of the second node written from the node is sent, and the first control data based on the received first control data. 3 means for controlling the output auxiliary device.

Further, a first node for inputting a signal from the first input auxiliary device and first control data based on the signal from the first input auxiliary device sent from the first node are transmitted. The second control is performed based on the first control data while receiving
A second node for controlling the output auxiliary device and a third node for controlling the third output auxiliary device operating at substantially the same time as the operation of the first input auxiliary device are connected on a common communication line. In the multiplex transmission system, the third node detects a failure of the first node and a third output when a failure of the first node is detected. And means for transmitting third control data in which the address of the second node is written from the third node instead of the first node in accordance with the operation of the auxiliary device.

As described above, the ID data registered in the failed communication node is additionally registered in another normal communication node for alternative display or operation, and the frame to be received by the failed communication node is changed to another. Since the system is configured so that it can be received by the normal communication node of the node, while maintaining the current system performance, the output auxiliary device of the node that is not related to the originally failed communication node effectively substitutes the indication or operation of the failure. be able to.

In addition, the failed communication node itself detects a failure of its own node or an output auxiliary device connected thereto and notifies the other normal communication node for alternative display or operation, and also notifies of the failure. Since the receiving node additionally registers the ID data of its own node so that it can receive the frame received by the faulty node that is not originally related, the node that is not related to the originally failed communication node while maintaining the current system performance. The output auxiliary device can effectively replace the failure indication or operation.

When the faulty node is the communication node that is the transmission source of the frame, the normal node that has detected the fault changes the ID data of the transmission destination and originally receives the frame from the faulty node. Since the substitute frame is transmitted to the other communication node in place of the faulty node, the risk caused when the output auxiliary device does not operate can be reduced.

[0024]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The multiplex transmission system of the embodiment described below is a so-called CSMA (Carrier Sense Mul).
This is an example applied to a network access method of tiple access / CD (Collision Detection) method.

<Common Embodiment> A common embodiment common to each embodiment described later will be described below. (Circuit Configuration and Connection Form of Communication Node) FIG. 3 is a diagram showing an example of the circuit configuration of the communication node used in the multiplex transmission network of the vehicle of this embodiment and the connection form to the network. Referring to FIG. 3, in the multiplex transmission system of the present embodiment, a communication node 10 (hereinafter referred to as a basic node) in which a CPU having an arithmetic processing function and a communication IC having an interface function with the multiplex transmission path are integrated and incorporated. , A communication node 20 in which a CPU and a communication IC are incorporated as separate ICs (hereinafter referred to as a high speed node), and does not have a CPU but has only an I / O function for inputting / outputting data to / from a multiplex transmission path. There are provided three types of communication nodes, which are a communication node 30 (hereinafter, a stand-alone node).

Of the above three types of communication nodes, the stand-alone node 30 performs high-level data processing such as the relationship between the rear differential switch and the communication node that controls the indicator lamp indicating that the switch is turned on. You can execute unnecessary communication control and simple input / output of data. In addition, the basic node 10 (communication node with built-in CPU)
The difference between the high speed node 20 and the high speed node 30 is that the basic node has a CPU and a communication IC integrated into one chip I.
In contrast to the C type, the high speed nodes are separately mounted as separate ICs.

The high speed node 20 is a high speed transmission line M.
It is connected to B1 and serves as a communication node for controlling the ABS and 4WS which mainly needs to send and receive data such as wheel speed which changes drastically with time, and is connected with a sensor 2 such as a wheel speed sensor. The basic node 10 is a switch 1 such as a main switch for centralized door lock and a remote control mirror switch.
Are connected. The basic node 10 serves as a window opening / closing switch or the like provided on the driver seat side door. As is well known, the switch in the driver's seat is capable of intensively opening and closing windows of other doors and locking doors, so that a basic node is used. Further, in the passenger seat and the rear seat, since the windows of the individual seats are simply opened and closed, the actuator 3 such as a window opening / closing motor is used.
A stand-alone node 30 connected to is sufficient. That is, the opening and closing of the windows in the passenger seat and the rear seat can be performed by the basic node 10 in the driver's seat or by the respective stand-alone nodes 30.

<Overall Configuration of Network> FIG. 4 shows the overall configuration of a network to which multiplex communication nodes for controlling electrical components such as switches and motors are connected. In the figure, instrument panel node 120, meter node 130, column node 1
40, cowl R node 150, front R node 210
Is a basic node and has a C for data processing inside.
Has PU. The tail node 200 is a stand-alone type node, and the ABS node 160, 4WS node 170, and REAR node 180 are high-speed nodes for high-speed communication.

Next, main electrical components connected to each communication node shown in FIG. 4 will be described. A hazard switch 122 for turning on a hazard lamp and a fog switch 123 for turning on a fog lamp are connected to the instrument panel node 120. Further, the meter node 130 is connected to a 4WS warning lamp 131 that lights up when the 4WS fails, and an ABS warning lamp 132 that lights up when the ABS fails. The column node 140 is connected to a buzzer 141 that emits a predetermined sound when the vehicle moves backward, a headlight switch 142 that lights headlights, and a turn switch 143 that lights left and right turn lamps. The front R node 210 has a front turn R on the right side of the front.
Lamp 211, front side turn R lamp 212,
The right headlamp RH213 is connected. Cowl R
The node 150 is a node to which a stop lamp switch 151 is connected, plays a role of synchronizing the turn-on lighting intervals of the front R node 210 and a tail node 200 described later, and also has a function as a management node. .

ABS node 160 has ABS valve unit 161, etc., and 4WS node 170 has 4WS drive motor 1.
71 etc. are connected. The engine node 180 executes the main control of the engine. The tail node 200 includes a rear turn L lamp 201 on the left side of the rear, a rear turn R lamp 202 on the right side of the rear, and a stop lamp LH2 on the left side of the rear.
03, the stop lamp RH204 on the rear right side is connected.

[Alternative control when communication node of this embodiment fails] Here, alternative control when the communication node of the embodiment of the present invention fails will be described. In the multiplex transmission system of the present embodiment, in order to prepare for a case where a communication node that controls a certain electric component unit fails on the network, another communication node as described below as the first to fifth embodiments is used. It is configured to execute the alternative control.

<First Embodiment> FIG. 5 shows a part of communication nodes in the entire network shown in FIG. 4, and shows a communication state between communication nodes in the alternative control operation of the first embodiment. . In the following, as a first embodiment, alternative control by a column node in the case of a meter node failure will be described.

(When the meter node is normal) In FIG. 5, for example, AB of the ABS node 160 or the 4WS node 170 is used.
When the S valve unit 161, 4WS node 170 fails, the ABS node 160 or the 4WS node 170
Sends a frame F1 for turning on the 4WS or ABS warning lamps 131 and 132 to the meter node 130. The meter node 130 in the normal state
F1 is once received by the communication IC 136. The communication IC 136 collates the ID data ID1 written in this frame F1 with the ID data stored in its own memory, and if there is the matching ID data in its own memory, it takes in this frame F1 and processes it, and the CPU135 Output to. CPU135
Is the 4WS warning lamp 131 or ABS based on the lamp lighting data entered in the data area of this frame F1.
The warning lamp 132 is turned on.

(At the time of meter node failure) On the other hand, if the meter node 130 fails, the ABS or 4WS further fails and the warning lamp lighting frame F1 is sent from the ABS node 160 and the 4WS node 170 to the meter node 130. The meter node 130 cannot receive this frame F1. For this reason, the 4WS warning lamp 131 or the ABS warning lamp 132 cannot be turned on, and the driver cannot be notified of the failure of the 4WS or ABS.
In order to avoid this state, in the first embodiment, the column node 140 is changed to the ABS node 160 and the 4WS node by changing the table of the ID data registered in the column node 140 instead of the receiving source meter node 130. The frame F1 transmitted from 170 is made to be receivable, and the buzzer 141 is sounded based on this frame F1 to execute the alternative control of the warning lamps 131 and 132. Specifically, the column node 140
Determines that some failure has occurred in the meter node 130 because the ACK data is not returned from the meter node 130. Then, the CPU of the column node 140
Reference numeral 145 is a communication IC so that the frame F1 sent from the ABS node 160 or the 4WS node 170 can be received by the communication IC which cannot normally perform the capture process because the ID data ID1 is not registered in the communication IC.
The table of ID data stored in the memory of 146
Rewrite to a new table containing D data ID1. 9 and 10 show the states of the ID data table before and after rewriting, respectively. In this rewriting of the table of ID data, as shown in FIGS. 9 and 10, all the tables can be rewritten from the state of FIG. 9 to the state of FIG.
You can also add data. In addition, in FIG. 10, ID 23 and ID are assigned to the addresses 3F and 40, which are vacant areas.
06 is added. In this way, by additionally registering the ID data ID1 of the meter node 130 of the reception source in the memory area of the communication IC 146 of the column node 140 which is not the node of the reception source originally, the frame F1 captured by the meter node 130 is captured by the column node 140. Then, instead of turning on the warning lamp 131 or 132 in the meter node 130, the alternative control can be executed by ringing the buzzer 141 in the column node 140. Also, the buzzer 141 of the column node 140
Is normally sounded when the vehicle is moving backward, but when notifying the driver of a failure of 4WS or ABS, the alarm interval is changed so that the driver can more easily recognize it.

<Second Embodiment> Next, as a second embodiment,
With reference to FIG. 5, the alternative control by the column node when the 4WS warning lamp 131 or the ABS warning lamp 132 of the meter node fails will be described. In the second embodiment, unlike the first embodiment, alternative control will be described when the 4WS warning lamp 131 or the ABS warning lamp 132 fails.

For example, the 4WS warning lamp 131 or the ABS warning lamp 132 due to disconnection or burnout of the lamp.
If the ABS node 160 or the 4WS node 170 fails, and the failure frame F1 is sent to the meter node 130, the meter node 130 outputs 4WS.
Warning lamp 131 or ABS warning lamp 13
2 cannot be lit. On the other hand, meter node 1
Since the output I / F 138 of the unit 30 is provided with a detection circuit for a lamp failure or the like, it can detect a failure such as a warning lamp. That is, the meter node 130 is the warning lamp 1
When the failure of 31 or 132 is detected, the frame F2 indicating the lamp failure of its own node is sent to the column node 140. The column node 140 that has received the frame F2 determines that a failure has occurred in the 4WS warning lamp 131 or the ABS warning lamp 132 of the meter node 130. Then, as in the first embodiment, the CP of the column node 140 is
The U 145 rewrites the table of ID data stored in the memory of the communication IC 146, as shown in FIGS. 9 and 10. The subsequent procedure is the same as that in the first embodiment, and detailed description thereof will be omitted.

<Third Embodiment> FIG. 6 is a diagram showing a part of communication nodes in the entire network shown in FIG. 4 and showing a communication state between communication nodes in the alternative control operation of the third embodiment. . In the following, as a third embodiment, alternative control by a column node or instrument panel node when the cowl R node fails will be described.

(When the cowl R node is normal) In FIG.
The cowl R node 150 normally has a frame F3 or a frame F3 indicating that the turn switch 143 of the column node 140 or the hazard switch 122 of the instrument panel node 120 is turned on and the switch of the turn lamp or the hazard lamp sent from each node is turned on. When F4 is received, a frame F5 for turning on and off the turn lamp is sent to the tail node 200 and the front R node 210. The CPUs 205 and 215 of the tail node 200 and the front R node 210 that have received this frame F5, based on the data written in the data area of this frame F5, turn the tail L when the left turn switch is turned on.
The lamp 201 and the front turn L lamp are turned on in synchronization with each other, and when the right turn switch is turned on, the tail turn R lamp 202 and the front turn R lamp 211 are also turned on. In this way, the cowl R node 150 controls the turning on of the front and tail turn lamps, and also performs the control of synchronizing the blinking intervals.

(Cowl R node failure) On the other hand, the cowl R
When the node 150 fails, the turn switch 141 of the column node 140 or the hazard switch 122 of the instrument panel node 120 is turned on, and the frame F3 indicating that the cowl R node 150 is turned on from each node or
Even if F4 is sent, the cowl R node 150 receives the frame F3 or F4 and turns on the turn lamp by turning on the frame F5 to the tail node 200 and the front R node 21.
Since it cannot be sent to 0, neither the front turn lamp nor the tail turn lamp can be turned on. In order to avoid this situation, in the third embodiment, when the source column node 140 or instrument panel node 120 sends a frame to the cowl R node 150, the tail node 200 and Since the ID data ID2 of the front R node 210 is additionally registered and transmitted, the tail node 200 and the front R node 2
10 becomes able to receive the frame F3 or F4 representing the switch-on sent from the column node 140 or the instrument panel node 120 to the cowl R node 150, and turns on the turn lamp based on the frame F3 or F4. More specifically, the tail node 200 and the front R node 210 determine that some failure has occurred in the cowl R node 150 because the ACK data is not returned from the cowl R node 150. Then, the CPU 215 of the front R node 210 causes the frame F3 or F4 transmitted from the column node 140 or the instrument panel node 120.
In order to be able to receive the ID data table stored in the memory of the communication IC 216 of the front R node 210 and the table of the ID data stored in the communication IC 206 of the tail node 200 via the multiplex transmission path. Instruct to rewrite. In this way, the I of the transmission cowl R node 210 is stored in the memory area of each communication IC of the tail node 200 and the front R node 210.
Cowl R node 1 by adding D data ID2
Frame F3 or F4 captured by 50 is tail node 200
Also, the front R node 210 can capture the turn lamp by receiving the frame F3 or F4 sent from the column node 140 or the instrument panel node 120 instead of controlling the turn lamp blinking by the cowl R node 150. Perform alternative control related to. To change the ID data, as shown in FIGS. 9 and 10, the table of the ID data stored in the memory of the communication IC of the reception source is rewritten. The subsequent procedure is the same as that in the first embodiment, and detailed description thereof will be omitted.

<Fourth Embodiment> FIG. 7 shows a part of communication nodes in the entire network shown in FIG. 4, and shows a communication state between communication nodes in the alternative control operation of the fourth embodiment. . As a fourth embodiment, an alternative control by the ABS node when the cowl R node fails will be described below.

(When the cowl R node is normal) In FIG.
Stop lamp switch 151 of cowl R-node 150
When is turned on, the cowl R node 150 sends a frame F6 for turning on the stop lamp to the tail node 200 of the transmission destination. Tail node 2 if normal
00 once receives this frame F6 by the communication IC 206. The communication IC 206 stores the ID data ID3 indicating the destination written in the frame F6 and the I stored in its own memory.
If the ID data that matches the D data is found in the memory of its own, the frame F6 is fetched and processed, and the tail stop lamps LH203 and RH based on the data entered in the frame F6.
Turn on 204.

(Cowl R node failure) On the other hand, the cowl R
When the node 150 fails, even if the driver turns on the stop lamp switch 151, the cowl R node 15
Since the frame F6 cannot be sent from 0 to the tail node 200, the stop lamp LH203 and the stop lamp RH204 will not light up. For this reason,
In this fourth embodiment, instead of the cowl R node 150,
The substitution control is executed by sending a frame F7 for turning on the stop lamp from the ABS node 160 to the tail node 200. More specifically, the ABS node 160 determines that some failure has occurred in the cowl R node 150 because the ACK data is not returned from the cowl R node 150. On the other hand, the ABS node 160
Normally, when the ABS of its own node is activated, the frame is transmitted to a specific node. Tail node 20
When the cowl R node 150 is normal, 0 does not receive the frame from the ABS node 160 because it is not the destination node of the ABS node 160. Therefore,
When the ABS node 160 detects a failure of the cowl R node 150, the CPU 165 of the ABS node 160 becomes the source node of the tail node instead of the cowl R node, and changes the ID data of the destination when the ABS of its own node operates. Then, the ID data D3 of the tail node 200 is entered so that the tail node 200, which is not the transmission destination node normally, can receive the frame F7, and the frame F7 representing the lighting of the stop lamp is transmitted. It should be noted that, contrary to the case shown in FIGS. 9 and 10, the ID data change does not change the ID data of the reception source, but the node of the node transmission source rewrites the table of the ID data of the transmission destination of the frame.

<Fifth Embodiment> FIG. 8 shows a part of communication nodes in the entire network shown in FIG. 4, and shows a communication state between communication nodes in the alternative control operation of the fifth embodiment. . In the following, as a fifth embodiment, alternative control by the front R node when a column node fails will be described.

(Normal column node) In FIG. 8, when the headlamp switch 142 of the column node 140 is turned on, the column node 140 sends the headlamp switch 142 to the front R node 210 and the engine node 180 of the transmission destination. The frame F8 indicating that is turned on is transmitted. The front R node 210 turns on the right headlight RH 213 based on the received frame F8. The engine node 180 increases the idle speed of the engine based on the frame F8.

(At the time of column node failure) On the other hand, when the column node 140 fails, the frame node F is sent from the column node 140 to the front R node 210 and the engine node 180 even if the driver turns on the headlamp switch 142. Headlamp RH2
When 13 is not lit, the idle speed of the engine cannot be corrected, which causes engine stall. Therefore, in the fifth embodiment, the headlamp R
For turning on the H213, see the fog lamp switch 12
3 is turned on, the fog lamp switch 123 is sent from the instrument panel node 120 to the front R node 210.
And a frame F10 indicating that the headlamp switch 142 has been turned on. Regarding the engine idle speed correction, when the headlamp RH 213 is turned on, the front R node 210 sends to the engine node 180 a frame F9 indicating that the headlamp is turned on. In this way, the alternative control is executed. Specifically, the instrument panel node 120 and the front R node 210 are the ACs from the column node 140.
Since there is no K data reply, the column node 140
It is judged that some failure has occurred in the. At this time, when the fog lamp switch 123 of its own node is turned on, the instrument panel node 120 sends out a frame F10 indicating that the fog lamp switch 123 and the headlamp switch 142 are turned on to the front R node 210, and the headlamp Turn on the RH 213. On the other hand, the front R node 210 becomes the transmission source node of the engine node 180 instead of the column node 140, and when the headlight RH 213 of its own node lights up, the transmission destination ID
The data is changed, and the ID data D4 is written and transmitted so that the engine node 180, which is not the transmission destination node at normal times, can receive the frame F9. As in the case of the fourth embodiment, the ID data is changed without changing the ID data of the receiver as opposed to the case shown in FIG. 9 and FIG. Rewrite the ID data table.

<Control Procedure> In the following, as a second embodiment,
An alternative control procedure when the ABS warning lamp of the meter node fails due to disconnection or the like will be described. Figure 11
Shows an alternative control procedure of the second embodiment. The process starts, and in step S10, the ABS of the meter node 130 is detected.
When the disconnection is detected in the warning lamp 132, the process proceeds to step S12, and the frame F2 indicating that the ABS warning lamp 132 is disconnected is sent to the column node 140. In step S14, the column node 1
40 receives frame F2. In step S16, the column node changes the table of ID data to be received by the own node based on the frame F2, and the ABS node 160
Enables reception of the frame F1 sent from. In this state of step S16, if an abnormality is detected in the wheel speed sensor of the ABS node 160 in step S18, in step S20 the ABS node 160 to the meter node 13
A frame F1 indicating that the ABS warning lamp 132 is turned on is transmitted to 0. In step S22, the column node 140 receives the frame F1 sent from the ABS node 160 because the table of the ID data is changed. In step S24, the buzzer 141 sounds based on the frame F1 sent from the ABS node 160. <Modification> It is obvious that the present invention is not limited to the above embodiment.

For example, in the above embodiment, the communication nodes connected to the network are those shown in FIG. 4, but the nodes are not limited to these nodes.

[0048]

As described above, according to the multiplex transmission system of the present invention, ID data registered in a failed communication node is additionally registered in another normal communication node for alternative display or operation. The system is configured so that the frame that the failed communication node should receive can be received by another normal communication node. Therefore, while maintaining the current system performance, the output of a node that is not related to the originally failed communication node The auxiliary device can effectively substitute the indication or operation of the failure.

Further, the failed communication node itself detects a failure of its own node or the output auxiliary device connected thereto, and notifies the other normal communication node for alternative display or operation, and also notifies the failure. Since the receiving node additionally registers the ID data of its own node so that it can receive the frame received by the faulty node that is not originally related, the node that is not related to the originally failed communication node while maintaining the current system performance. The output auxiliary device can effectively replace the failure indication or operation.

When the faulty node is the communication node of the frame transmission source, the normal node which has detected the fault is supposed to change the ID data of the transmission destination and originally receive the frame from the faulty node. Since the substitute frame is transmitted to the other communication node in place of the faulty node, the risk caused when the output auxiliary device does not operate can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a frame format used in a conventional communication system.

FIG. 2 is a diagram showing a detailed configuration of a communication node used in the multiplex transmission network of the vehicle according to the present embodiment.

FIG. 3 is a diagram showing an example of a network system in which a basic node, a high speed node, and a standalone node are mixed.

FIG. 4 is a diagram showing a connection configuration of a multiplex communication node that controls electrical components such as switches and motors to a network.

5 is a diagram showing a part of communication nodes in the entire network shown in FIG. 4 and showing a communication state between communication nodes in the alternative control operation of the first and second embodiments.

FIG. 6 is a diagram showing some communication nodes in the entire network shown in FIG. 4 and showing a communication state between communication nodes in the alternative control operation of the third embodiment.

FIG. 7 is a diagram showing a part of communication nodes in the entire network shown in FIG. 4 and showing a communication state between communication nodes in an alternative control operation of the fourth embodiment.

FIG. 8 is a diagram showing a part of communication nodes in the entire network shown in FIG. 4 and showing a communication state between communication nodes in an alternative control operation of the fifth embodiment.

FIG. 9 is an ID in the communication node of the reception source before rewriting
It is a figure which shows the table of data.

FIG. 10 shows I in the receiving communication node after rewriting.
It is a figure which shows the table of D data.

FIG. 11 is a flowchart showing an alternative control procedure of the second embodiment.

[Explanation of symbols]

MB1, MB2 ... Multiplex transmission line 10 ... Basic node 20 ... High speed node 30 ... Standalone node

Continuation of front page (56) Reference JP-A-3-110942 (JP, A) JP-A-3-196351 (JP, A) JP-A-5-145976 (JP, A) JP-A-63-207753 (JP , A) JP 7-203553 (JP, A) JP 4-342632 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04L 12/00 H04Q 9/00

Claims (12)

(57) [Claims] 1. A first node for controlling a first output auxiliary device, a second node for controlling a second output auxiliary device, and a second node for controlling the second output auxiliary device.
Is a multiplex transmission system in which a third node that controls a third output auxiliary device based on control data transmitted from the node is connected on a common communication line, wherein the first node is the first node. Failure detection means for detecting whether or not the third node has failed, and control in which the address of the third node transmitted from the second node is entered when the failure of the third node is detected. It is characterized by comprising means for changing the address of its own node so that it can receive data, and means for controlling the first output auxiliary device based on the control data received from the second node. Multiplex transmission system. 2. The first node determines that the third node has failed if a predetermined signal is not returned from the third node in response to other control data sent to the third node. The multiplex transmission system according to claim 1, wherein: 3. The third node itself detects whether the own node has failed, and communication data for notifying the first node of the own node failure when the own node fails. And a means for transmitting the communication data, wherein the first node determines that the third node has failed when the communication data is received from the third node. The described multiplex transmission system. 4. The multiplex transmission system according to claim 1, wherein the third output auxiliary device is an indicator for informing an occupant of a malfunction of an electric component of an automobile. 5. The multiplex transmission system according to claim 1, wherein the first output auxiliary device is an alarm device for informing an occupant of an operating state of an electric component of an automobile. 6. A first node for inputting a signal from a first input auxiliary device, and first control data based on the signal from the first input auxiliary device sent from the first node. A second node that receives and sends second control data to a third node based on the first control data and a third output auxiliary device based on the second control data A multiplex transmission system in which a third node is connected to a common communication line, wherein the third node detects a failure in the second node, and the second node, Means for changing the address of its own node so as to be able to receive the first control data in which the address of the second node transmitted from the first node is received, when a failure of the node is detected, Based on the received first control data, Multiplex transmission system characterized by comprising a means for controlling the output accessory. 7. The multiplex transmission system according to claim 6, wherein the second control data is data for operating the third output auxiliary device in synchronization with each other at predetermined intervals. 8. The first input auxiliary device is a turn switch operated when the vehicle turns left and right, and the third input auxiliary device is the turn switch.
7. The multiplex transmission system according to claim 6, wherein the output auxiliary device is a turn lamp provided on the front, rear, left and right of the vehicle. 9. The first input auxiliary device is a hazard switch operated when an automobile is in an abnormal state, and the third output auxiliary device is a hazard lamp provided in front, rear, left and right of the automobile. The multiplex transmission system according to claim 6. 10. A first node for inputting a signal from a first input auxiliary device, and first control data based on the signal from the first input auxiliary device sent from the first node. A second node that receives and controls a second output auxiliary device based on the first control data and a third output auxiliary device that operates at substantially the same time as the operation of the first input auxiliary device A third node connected to a common communication line on a common communication line, wherein the third node detects a failure of the first node; When the failure of the first node is detected, the third control in which the address of the second node is entered from the third node instead of the first node in accordance with the operation of the third output auxiliary device. And a means for transmitting data. Stem. 11. The first input auxiliary device is a stop lamp switch that is turned on or off by a brake operation of an occupant, and the third control data is data for controlling an antilock brake system. The multiplex transmission system according to claim 10, wherein: 12. The first control data is data for increasing and correcting an idling speed of an engine, and the third control data is an operation signal of an auxiliary device that affects an engine load. The multiplex transmission system according to claim 10, characterized in that