JPH0746667A - Multiplex communication system for vehicle - Google Patents

Abstract

PURPOSE:To obtain a multiplex communication system for vehicle enabling the existence of a multiplex communication node having no data processing function and securing the consistency of the multiplex communication. CONSTITUTION:In a multiplex communication system for vehicle where plural multiplex communication nodes controlling plural electrical units of a vehicle, respectively, are connected on a common communication line 1000, this system includes a first multiplex communication node 112 and a second multiplex communication node 111. The multiplex communication 112 is provided with a first communication control LSI executing a communication control exchanging data for the remote control mirror motor 404 of this multiplex communication node 112 with only the multiplex communication node 111. The multiplex communication node 111 is provided with a second communication control LSI executing the communication control for exchanging data with other multiplex communication nodes and a CPU detecting that the multiplex communication node 111 receives the data for the multiplex communication node 112 from other multiplex communication nodes and performing a conversion processing for this data in a form that the communication control LSI of the multiplex communication node 112 is possible to perform a reception processing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle multiplex communication system having a plurality of multiplex communication nodes for controlling a plurality of electrical equipment units, and more particularly to reduction of the cost of the entire system.

[0002]

2. Description of the Related Art In order to eliminate the enlargement and complexity of wiring (wire harness) that connects between electronic parts (electrical unit) of a vehicle, multiplex communication is drawing attention. In the multiplex communication, a plurality of data are sent out on one wiring by time division multiplexing, and basically, serial transmission is the basis.

In the field of automobiles, the network forms of the multiplex communication are considered to be classified into a complete multiplex type and a partial multiplex type, or a centralized type and a distributed type. The partial multiplex type is a mixture of a non-multiplex communication part and a multiplex communication part. In the multiplex communication part, switches, loads, etc., which are distributed in distance, are connected by a multiplex transmission unit. It is said that the total number of wires is increased, but the number is increased, because separate wires are required between the unit, the switch, and the load. In the centralized type, a plurality of slave transmission units are connected to one master transmission unit. Although the diameter reduction effect can be obtained, the system goes down when the master goes down, and design changes are required. It is said to have drawbacks such as difficulty. On the other hand, although the distributed type is costly, it is in the limelight because of its large diameter reduction effect, high reliability for partial down, and high flexibility for design changes (for example, JP-A-6
2-4658).

FIG. 1 shows a format of a communication frame adopted in a conventional multiplex communication system for automobiles, and FIG. 2 shows an example of a node configuration. In FIG. 1, frame F
Has a frame structure having an SD (Start Delimiter) 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 indicating which signal should be preferentially processed when a plurality of multiple nodes transmit data at the same time and the signals collide. In this embodiment, a lower priority bit value is assigned a higher priority. This is because the low level is WIRED-OR in the bus 1. 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 1, so that the lower node has a different "priority code" from its own. Since it has changed to, a collision is detected. Then, 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 destination of the frame and corresponds to so-called functional addressing. This ID code is attached to the node of the transmission source. The number of data following this is written in the "data length", 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. And the field following the data is CR
By confirming this with the C check code (error detection code), it is possible to know 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. FIG. 2 is a diagram showing a general configuration of a communication node used in a vehicle network. Each node is connected to the transmission line 10 via the communication LSI 101. Reference numeral 100 denotes a control CPU, which operates according to a program stored in the RAM / ROM 102. The CSMA / CD system physical layer level protocol control is performed by the LSI 101. This communication node is connected to the electrical equipment unit 104.
This unit is, for example, an EGI controller for engine control or a node of meters.

The CPU 100 controls the LSI 101,
In addition, control is performed to process data from the LSI 101 and pass the data to the electrical unit 104, or to pass data from the electrical unit 104 to the LSI 101. That is, the frame data on the bus is converted into a format usable by the electrical component unit 104, and
The data from 4 is converted into a frame format. Another important role of the CPU 100 is management of ACK data. That is, as described above, in this communication method,
When all nodes (communication LSI 101) receive the frame data from other nodes without error, the ACK bit is returned to the node that sent the frame data. Therefore, by checking the contents of this ACK field, it is possible to know which node could not receive the frame transmitted by itself. This check work is C
PU100 is entrusted. This is the communication LSI 101
Is limited to communication control, and high-level data processing is performed by the CPU 10.
This is because 0 is trying to do it.

[0009]

In the multiplex communication system as described above, the CPU 100 is required for each node, so that the system as a whole becomes expensive. Therefore, it has been proposed to provide some of the nodes such that the CPU 100 is not provided. Such a node cannot perform high-level data processing because it does not have a CPU. However, for example, in the case of a node that controls a switch and an indicator lamp that indicates that the switch has been turned on, high-level data processing is not required, and therefore an LSI that can execute communication control and simple input / output of data. Can be dealt with. Such a node is called a "stand-alone" type node for convenience, and the CP
Nodes with U are called "intelligent" type nodes.

FIG. 3 shows an example of a network system in which the above-mentioned stand-alone type node and intelligent node are mixed. In the example of FIG. 3, the intelligent type node is the node 200 and the stand-alone type nodes are the nodes 201, 202 and 203. Node 200
Is a node for a window opening / closing switch provided on the driver seat side door, and includes nodes 201, 202, 20.
Reference numeral 3 is a node for a window opening / closing switch provided on the door of each seat. As is well known, since the switch in the driver's seat can centrally open and close windows of other doors, an intelligent node is used. In the passenger seat and the rear seat, the stand-alone type is sufficient because the windows of the individual seats are simply opened and closed. That is,
The windows in the passenger seat and the rear seats can be opened and closed by the intelligent node 200 in the driver's seat or by the respective stand-alone nodes.

By the way, in the distributed multiplex communication system, since the field position in the frame of each data is fixed, a node receives one data in one frame, and then in the next frame. When the same data exists, it is not known whether that data reflects the latest state of the sensor. For example, when the output value of a certain sensor in the frame shows the same value, it is impossible to determine whether the sensor output has not changed or happens to be the output value of the previous sensor.
Therefore, unless some identification method is introduced, the same data may be captured as new data many times.

In order to eliminate such inconvenience, it is conceivable to provide each data with a "tag" bit. Here, the sender node of the sensor data sets the value of the tag to 0 when sending the data, and when the data is taken in by the destination node, the destination node changes the tag to 1. Shall be done.

However, since such "tag" processing requires a high data processing capability, it is not possible with the above-mentioned stand-alone type multiplex communication node having no internal CPU. The present invention has been proposed to solve the above-mentioned problems of the prior art, and an object thereof is to enable the existence of a multiplex communication node having no data processing function, and yet ensure the consistency of multiplex communication. We are proposing a multiplex communication system for vehicles.

[0014]

The object of the present invention is to provide a vehicle multiplex communication system in which a plurality of multiplex communication nodes for controlling a plurality of electrical units of a vehicle are connected on a common communication line. , The multiplex communication system includes at least first and second multiplex communication nodes, and the first
The multiplex communication node comprises a first communication control device for executing communication control for exchanging data for the electrical unit of the first multiplex communication node only with the second multiplex communication node. A second communication control device for executing communication control for exchanging data with another multiplex communication node; and the second multiplex communication node for the first multiplex communication. Means for detecting that the first data for the node has been received from a multiplex communication node other than the first and second multiplex communication nodes, and an output of this detection means for receiving the first data , The first
And a data processing device for converting the first communication control device of the multiplex communication node into a form in which reception processing can be performed.

Since the first multiplex communication node has no data processing device, it contributes to cost reduction of the entire network. On the other hand, since the processing device of the second multiplex communication node processes the communication data in a form that can be processed by the first multiplex communication node, the consistency of the entire network can be obtained.

[0016]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. <Network Configuration> FIG. 4 shows each electric component unit of a vehicle provided with a network according to an embodiment of the present invention. Listed in order, 100 is a mirror switch provided on the instrument panel. The switch 100 includes a switch for the right mirror 206 and a switch for the left mirror 405. Each switch has a closed position and an open position. The right mirror 206 is driven by the motor 205. The left mirror 405 is driven by the motor 404. This vehicle has left and right doors (FR, FL) on the front side and left and right doors (RR, R) on the rear side.
L). Each door has a switch (PW SW 202, 402, 301, 501) operated by the passenger to open and close the window glass,
Solenoid for driving door lock mechanism (LKSL20
1, 401, 302, 502) and a motor for opening and closing the window glass
(M204, 403, 303, 503) are provided.

FIG. 5 shows a connection configuration of a multiplex communication node for controlling electrical components such as the switches and motors of FIG. 4 to the network. In the figure, the instrument panel node 110 and the FR door node 111 are intelligent nodes, and internally have a CPU for data processing as will be described later. Also, FL door node 112, RR door node 113, R
The L door node 114 is a stand-alone node.

The operation and operation of each electric component will be described below. When locking the door, the lock switch 203 of the FR door is operated. Operating this switch will lock all doors. In this case,
A frame of the format shown in 3 is sent from the FR door node to each door node. Each door node that receives this frame drives the respective door lock solenoid to lock the door.

The occupant can open and close the window glass of the door in each seat. FL door, RR door, RL
In the door, when an occupant operates each PW SW, each node detects the switch operation and drives each motor to open and close the window glass. The driver can operate the opening and closing of the window glass of all doors in the FR door position. In FIG. 5, the PW main switch 202 has four switches (see FIG. 6). To open the FL, RR, and RL door windows of the four switches, operate each switch. In response to this switch operation, the node 111 sends a frame to open the window glass to the node of the corresponding door.

When the driver wants to rotate the remote control type door mirror, either one or both of the mirror switches 100 is operated. When this switch is operated, the instrument panel node 110 sends a frame indicating that the switch operation has been performed to the FR door node 111.
Upon receiving this frame, the FR door node 111 drives the right mirror motor 205. Further, if the driver operates the switch for operating the left mirror, the FRc door node 111 will move the FL door node 112 to the FL door node 112.
Send a frame to open the door window. That is, even when the driver operates the left mirror switch, the instrument panel node 110 does not directly send the frame to the FL door node 112 but once sends the frame to the FL door node 112 via the FR door node 111. The reason for this is that the FL door node 112 is a stand-alone type node and therefore cannot process data, which will be described in detail later. <Intelligent Node> FIG. 6 shows the relationship between the configuration of the FR door node 111 and the electrical unit connected to the node. The communication node 111 shown in the figure is an intelligent type node, and includes a bus I / F circuit 1101.
And a CPU 110 having 9-port input and 6-port output
4 (the number of actual input / output ports is larger when the unused ones are included), the multiplex communication LSI 1102,
And a power supply circuit 1103. Multiplex communication LSI 1103
Executes a communication control procedure based on CSMA / CD,
It also controls the transmission of the above-mentioned ACK bit.

The power supply circuit 1103 converts the B voltage from the battery into a predetermined DC voltage and monitors the voltage.
The switch FL provided in the window switch group 202 is a switch 402 for opening and closing the passenger seat window, and the switch RL is a switch 50 for opening and closing the rear seat right window.
1. The switch RR is a switch 301 for opening and closing the window on the right side of the rear seat. Also, the door lock switch
The switch 203 locks all the doors at once.

In the network system of FIG. 5, intelligent nodes are used for the instrument panel node 110 as well as the node 111. This instrument panel node 110
Is the I / F circuit 1101 and the multiplex communication LSI 110 of FIG.
2, the power supply circuit 1003 and the CPU 1104 are the same. However, the CPU of the instrument panel node 110
Various switches on the instrument panel are connected to the input port of, and various lamps are connected to the output port.

FIG. 7 shows the configuration of the FL door position node 112 as an example of a stand-alone node. Other standalone nodes have substantially the same configuration. The node 112 has a bus I / F circuit 1210, a power supply circuit 1211, and a multiplex communication LSI 1212. The bus I / F circuit 1210 is an intelligent node I
The same as the / F circuit 1101, and the power supply circuit 1211 is the same as the circuit 1103. The input port of the LSI 1212 is connected to the window switch 402, and the output port is connected to the window motor 403 and the lock solenoid 401. <Standalone Node> FIG. 8 shows the internal structure of the standalone node of FIG. Transmission control circuit 125
0, the reception control circuit 1256 executes the control procedure of CSMA / CD. The ACK control circuit 1255 is the control circuit 125.
If there is no error in the frame received by 6, the control for transmitting the ACK bit is executed. 18 and 119 show the control functions of the stand-alone node 112 as circuit diagrams. <Structure of Frame> FIG. 9 shows a relationship between a transmission source and a transmission destination of a frame exchanged between the nodes of the network system of FIG. An example of valid frames in this network system is FID as shown in FIG.
There are 6 types, ie, 01 to 06. In FIG. 9, a double circle mark indicates a transmission source of the frame, a single circle indicates a transmission destination, and an X mark indicates a node that does not correspond to the transmission source or the transmission destination.

FIG. 10 shows a frame of FID = 01, 02 or 03, which means that the 2-bit PW is “01”.
When it is, the window is opened, and when it is "10", the window is closed. Here, FID = 01 → opening and closing of FL door window FID = 02 → opening and closing of RR door window FID = 03 → opening and closing of RL door window FID = 01 → opening and closing of FL door window As shown in the table of FIG. Then, the frame of FID = 01 is processed only by the FL node 112, the frame of FID = 02 is processed only by the RR node 113, and the frame of FID = 03 is processed by only the RL node 114.

FIG. 11 shows a format of a frame for opening and closing the remote control mirror, which is sent from the instrument panel node 110 to the FR door node 111.
The ID of this frame is FID = 04. Whether to open or close the mirror is represented by 4 bits from the 3rd bit of the data area. That is, the 2nd bit from the 3rd bit is data for controlling the opening and closing of the motor 205 at the FR position. The next 2 bits are data for controlling the opening / closing of the motor 404 in the FL position. These two sets of 2-bit data have 1-bit tag data V / IV in which each data is valid. This tag allows the receiving node to know whether other stupid and other corresponding data is valid. As shown in the table in FIG. 9, the frame of FID = 04 is generated only by the instrument panel node 110 and received by only the FR door node 111. Upon receiving this frame, the FR node 1111 drives the mirror motor 205 if the data has a bit for driving the motor.

If the frame has a bit for driving the FL door mirror, a frame (FID = 04) of the format shown in FIG. 12 is sent to the FL door node 112. As shown in FIG. 9, only the FL door node 112 receives this frame (FID = 04) and processes it. As shown in FIG. 12, this type of frame does not have the aforementioned V / IV tag. This is removed by the FR door node 11. Since the FL door node 112 is a stand-alone type node as described above, it is a C for data processing.
This is because this V / IV tag cannot be processed because it has no PU. In other words, in the network system of FIG. 4, a normal frame has a tag V / IV indicating valid / invalid of data, so that a standalone node that cannot process such a V / IV tag is used. On the other hand, by removing the V / IV tag, it allows the network system to mix stand-alone nodes with intelligent nodes. An intelligent node, such as an FR door node, that sends data only to a stand-alone node may be configured so that its CPU removes the V / IV tag and then forwards the data to the stand-alone node. For example, instrument panel nodes, etc. that need to be added have to add the V / IV tag to the frame, so when communicating with a stand-alone node, once go through the intelligent node and remove the V / IV tag there. Then, send it to the standalone node.

FIG. 13 shows a format of a frame for locking and unlocking all doors. This frame is generated only by the FR door node 111 and received by all the other three door nodes (see FIG. 9). <Control Procedure> FIG. 14 shows a control procedure in the instrument panel node 110. In step S2, it is checked whether the LSI of the node 110 itself has received the frame from the line 1000. If such data is received, step S1
At 4, the process for the data in that frame is performed. LS
If I is not receiving data, the input from any switch attached to the instrument panel node is checked in step S4. In step S6, if the operation switch of the remote-control mirror is operated, a frame of FID = 04 (FIG. 11) is created in step S8. In step S10, V / IV = 1 is set to indicate that the data is valid. Then, the frame w is output to the LSI of the instrument panel node 110. The LSI will send the frame out on line 1000.

FIG. 15 shows the control procedure of the main routine of the FR door node 111. Which CPU11 of this FR
In step S100, the 04 checks using the flag F whether or not there is data to be transmitted on the line 1000. F
If = 1, the data is transferred to LSI1 in step S400.
Send to 102. LSI 1102 will send out on line 1000 in the form of frames. If there is no transmission data, the LSI 1102 sets the line 1000 in step S102.
Find out if you were receiving data from. If no reception data is input, the control and status of the switches attached to the FR node are input in step S300. This control procedure will be explained by FIG. On the other hand, if there is received data, the received data is processed in step S200. Details of this process will be described in connection with FIG.

A case where the driver operates various switches at the FR door position will be described. When the door lock switch 203 is operated, the process proceeds to step S302 ... → Step S310 → step S312, and the lock solenoid of the FR door is turned on / off in accordance with the operation in step S312. Further, in order to intensively control the lock of the other three doors, FID =
Create the 06 frame (Fig. 13). Then, the flag F indicating that there is transmission data is set to 1. This flag F
Is set to 1, step S40 in FIG.
The frame is output to the LSI 1102 at 0 as described above.

In order to open and close the FR door window, PW (power
window) If the SW 202a is operated, step S3
02 → step S304 → step S306 → step S308 to control the wind motor 204.
PW (power window) SW2 to open and close the FL door window
If 02b is operated, the process proceeds from step S302 → ... → step S318 → step S320 to create a frame with FID = 01 (FIG. 10) in step S320, and in step S322, a flag F indicating that there is transmission data.
Set to 1.

In order to open and close the window of the RR door, PW (power
window) If the SW 202c is operated, step S3
02 → ... → Step S324 → Step S326, the frame with FID = 02 (FIG. 10) is created in step S326, and the flag F indicating that there is transmission data is set to 1 in step S328. When the PW (power window) SW 202d is operated to open / close the window of the RL door, the process proceeds to step S302 → ... → step S330 → step S332 to create a frame with FID = 03 (FIG. 10) in step S332. Then, in step S334, a flag F indicating that there is transmission data is set to 1.

Here, the control of the stand-alone node on the receiving side will be described. This standalone node is CP
Since it has no U, there is no special control procedure for it.
FL, RR, which is a standalone node
Each node in the RL door has a circuit as shown in FIGS. The circuit of FIG. 18 is a circuit for controlling the wind motor, and when any LSI in the garden receives the frame of FID = 01 to 03, the motor is driven according to the value of the PW bit. The lock solenoid is also controlled according to the value of the lock bit. In FIGS. 18 and 19, the signal enable indicates the timing when the LSI may receive a frame and control the electrical unit connected to the node.

Next, the instrument panel node 110 is used to
FR door node 11 with FID = 04 frame by control procedure of 4
I will explain when I sent it to 1. In such a case, the CPU of the node 111 is step S100 → step S1
02 → step S200, the control procedure of FIG. 17 is executed. That is, the process proceeds from step S202 of FIG. 17 to step S204, and the tag bit V / IV is calculated. Next, if the operation is to drive the FR side mirror motor and the tag is 1 (valid), step S208.
Then, the process proceeds to step S6 to control the motor 205 of the right remote control mirror. Further, if the operation is to drive the mirror motor on the FL side and the tag is 1 (valid), step S
The process proceeds from step 210 to step S212, a frame of FID = 05 is created, and the transmission data flag F is set to 1 in step S214. You This frame is FL door node 112
Will be sent to. Now that the tag V / IV has been removed, the standalone node 112 will be able to process the frame. <Modification> It is obvious that the present invention is not limited to the above embodiment.

For example, in the above embodiment, the nodes connected to the network are those shown in FIG. 4, but the nodes are not limited to these nodes. That is, a stand-alone type node having no data processing function and an intelligent type node having a data processing ability are connected to the same network, and the intelligent type node sends data to another node with predetermined information data added. On the other hand, if the stand-alone type node cannot handle the addition of the information data, the present invention can be applied to any type of any number of nodes connected to the network. Applicable.

Further, the present invention can be applied to other than the control of the window motor and the control of the door lock.

[0036]

As described above, according to the system of the present invention, since the first multiplex communication node such as the FL door node does not have the data processing device such as the CPU,
Contributes to cost reduction of the entire network. On the other hand, FR
Since the processing device of the second multiplex communication node, such as the node, processes the communication data in a form that can be processed by the first multiplex communication node, the integrity of the entire network can be obtained. That is, it is possible to provide a multiplex communication node that does not have a data processing function, and it is possible to provide a multiplex communication system for a vehicle that ensures the consistency of multiplex communication.

[Brief description of drawings]

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

FIG. 2 is a diagram illustrating a configuration of a conventional multiplex communication node.

FIG. 3 is a diagram showing an example of a configuration of a conventional automobile network.

FIG. 4 is a diagram showing an arrangement of electric components of a vehicle in which the present invention is applied to an automobile system.

5 is a diagram showing a network configuration of an embodiment applied to the vehicle system of FIG.

FIG. 6 is a diagram showing a configuration of an intelligent communication node according to an embodiment.

FIG. 7 is a diagram showing a configuration of a stand-alone communication node according to the embodiment.

FIG. 8 is a diagram showing a more detailed configuration of a stand-alone communication node according to the embodiment.

FIG. 9 is a diagram showing a relationship between a transmission source and a transmission destination of a frame exchanged on the network of the embodiment.

FIG. 10 is a diagram showing a format of a frame for opening and closing a door window.

FIG. 11 is a diagram showing a format of a frame for driving a motor of a remote control mirror of a door.

FIG. 12 is a diagram showing a format of a frame for driving a motor of a remote control mirror of a left door.

FIG. 13 is a diagram showing a format of a frame for driving a door lock.

FIG. 14 is a flowchart showing the control procedure of the instrument panel node.

FIG. 15 is a flowchart showing a main routine of an FR door node control procedure.

16 is a flowchart illustrating a partial subroutine of the flowchart of FIG.

FIG. 17 is a flowchart illustrating a partial subroutine of the flowchart of FIG.

FIG. 18 is a diagram showing a partial circuit configuration of a standalone node.

FIG. 19 is a diagram showing a partial circuit configuration of a standalone node.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Terayama 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Motor Corporation

Claims (4)

[Claims] 1. A vehicle multiplex communication system in which a plurality of multiplex communication nodes for controlling a plurality of electric components of a vehicle are connected to a common communication line, and the multiplex communication system includes at least first and second communication systems. The multiplex communication node, the first multiplex communication node executes communication control for exchanging data for the electrical unit of the first multiplex communication node only with the second multiplex communication node. A second communication control device for executing communication control for exchanging data with another multi-communication node; Means for detecting that the communication node has received first data for the first multiplex communication node from multiplex communication nodes other than the first and second multiplex communication nodes; And a data processing device that receives the output of the first data and converts the first data into a form that can be received by the first communication control device of the first multiplex communication node. Multiplex communication system for vehicles. 2. A multiplex communication node other than the first and second multiplex communication nodes, and
2. The multiplex communication system for a vehicle according to claim 1, wherein communication data to which is added information indicating validity / invalidity of data is exchanged, and the data processing device performs a process of removing the additional information. 3. The vehicle according to claim 1, wherein the electrical component unit of the second multiplex communication node is a switch which is operatively associated with the electrical component unit of the first multiplex communication node. Multiplex communication system. 4. The vehicle according to claim 3, wherein the electrical component unit of the second multiplex communication node is a switch that is operationally higher than the electrical component unit of the first multiplex communication node. Multiplex communication system.