JPH1051474A - Vehicle data transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle data transmission system in which a bus occupancy rate of each node on a network is made efficient. SOLUTION: A plurality of nodes 1a-1e are connected to a bus 3 and a token is circulated between the nodes in a predetermined order and a node acquiring the token sends data to the bus 3 in the vehicle data transmission system. In the nodes 1a-1e, an address management table 30a stores node connection information denoting all the nodes 1a-1e connecting to the bus 3 and a transfer destination setting section 23a references the stored node connection information to set the transfer destination node of the token and a transmission reception section 21a sends a transfer message of the token to the transfer destination node of the set token.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plurality of nodes mounted on a vehicle connected to a bus, circulating a transmission right between the nodes in a predetermined order, and a node acquiring the transmission right being connected to the bus. The present invention relates to a vehicle data transmission system for transmitting data to a vehicle, and more particularly to a vehicle data transmission system capable of increasing the efficiency of the bus occupancy of data to be transmitted.

[0002]

2. Description of the Related Art In a vehicle such as an automobile, a plurality of electronic control nodes (units) are connected to a common bus, and data is transmitted and received between the nodes. In this case, a token passing method is known in which the transmission right is circulated between the nodes in a predetermined order, and the node that has acquired the transmission right sends data to the bus.

[0003] As a technique of a vehicle data transmission system employing this kind of token passing system, for example, there is one disclosed in Japanese Patent Laid-Open No. 6-269048.

[0004] Japanese Unexamined Patent Publication No. 6-269048 discloses, as shown in FIG. 5, an address of a destination node as a value obtained by adding a value 1 to an address of the own node, and a transfer right transfer message to the destination node. (Step S11)
1).

[0005] Then, it is determined whether or not there is a reception response message of the transmission right transfer message from the transmission destination node (step S113). If there is the reception response message, it is determined that the network is normal (step S11).
5), end the processing.

However, if there is no reception response message, the address of the next destination node is set (step S117), and it is determined whether the set address is equal to the address of the own node (step S1).
19).

If the set address is different from the address of the own node, the process returns to step S111 to send a transmission right transfer message to the next destination node based on the address of the next destination node. The processing up to step S119 is performed.

When the set address becomes equal to the address of the own node, the network is determined to be abnormal.

According to such a process, it is possible to determine the abnormality of the system while performing the token transfer process.

[0010] In addition, a transmission right transfer destination message (hereinafter referred to as a transmission transfer destination message) and transmission data are sequentially transmitted between a plurality of nodes of the conventional vehicle data transmission system using the token passing system. In this case, the operation is performed according to the flowchart shown in FIG.

First, it is determined whether the own node has received the transmission delegation message (step S201). If the own node has received the transmission delegation message, the transmission delegation address is set to the next address value. (Step S203).

Next, it is determined whether the transmission data has been set in the transmission buffer (step S205).
When the transmission data is completely set in the transmission buffer, the transmission delegation destination message is transmitted to the next delegation destination node (step S207).

Further, it is determined whether or not the processing has been completed (step S209). If the processing has not been completed, the process returns to step S201.

On the other hand, if the own node has not received the transmission delegation message in step S201,
The necessary data is stored in a random access memory (RAM) (step S211).

[0015]

However, in the conventional token passing method, each node transmits a transmission delegation message regardless of a node currently connected to the network or a node not currently connected to the network. It was sent over the network (bus).

There is also a case where a certain node is disconnected from the bus. In such a case, the transmission transfer destination message unnecessarily occupies the bus, and the transmission data cannot be efficiently transmitted via the bus.

Further, a certain node may be additionally connected to the bus. In such a case, since the transmission delegation message is transferred only to the node first connected to the bus, the transmission delegation message could not be transferred to the added node.

For this reason, at present, it is desired to transfer the transmission delegation destination message only to the nodes connected to the bus, and to improve the efficiency of the bus occupancy.

An object of the present invention is to provide a vehicle data transmission system capable of improving the efficiency of bus occupancy of each node on a network.

[0020]

The present invention employs the following means in order to solve the above-mentioned problems. A vehicle data transmission system according to claim 1, wherein a plurality of nodes are connected to a bus, a transmission right is circulated among the nodes in a predetermined order, and a node having acquired the transmission right sends data to the bus. , Each of the nodes includes storage means for storing node connection information indicating all nodes connected to the bus, and a transfer right transfer destination node with reference to the node connection information stored in the storage means. And a transmission / reception unit that sends a transmission right transfer message to the transmission right transfer destination node set by the transfer destination setting unit.

According to the present invention, the storage means stores the node connection information indicating all the nodes connected to the bus, and the transfer destination setting means refers to the node connection information stored in the storage means. The transmission right delegation destination node is set, and the transmission / reception means sends the transmission right delegation message to the transmission right delegation destination node set by the delegation destination setting means.

That is, since the transmission delegation destination message is transferred only to the node currently connected to the bus, the efficiency of the bus occupancy can be improved.

Preferably, one of the plurality of nodes sends the node connection information to all nodes.

According to the present invention, one of the plurality of nodes
Since one node sends the node connection information to all nodes, all nodes can determine the transmission delegation destination node with reference to the node connection information.

According to a third aspect of the present invention, when one of the plurality of nodes changes the node connected to the bus by addition or reduction, the changed node connection information at that time is transmitted to all the nodes. The point is to send it.

According to the present invention, one of the plurality of nodes
One of the nodes sends the changed node connection information to all the nodes when the node connected to the bus is changed by addition or reduction, so that the transmission delegation destination is changed according to the changed node connection information. Node can be determined,
Further, efficiency of the bus occupancy can be improved.

In a preferred embodiment, the apparatus further comprises a judging means for judging whether the node connection information indicating the delegation destination node set by the delegation destination setting means matches the node connection information stored in the storage means, The delegation destination setting unit increments the delegation destination node, and when the node connection information indicating the delegation destination node matches the node connection information stored in the storage unit, transfers the node indicating the matched node connection information to the transmission right. The gist is to set to the destination node.

According to the present invention, the judging means judges whether or not the node connection information indicating the delegation destination node set by the delegation destination setting means matches the node connection information stored in the storage means.

The delegation destination setting means increments the delegation destination node, and when the node connection information indicating the delegation destination node matches the node connection information stored in the storage means, transmits the node indicating the matched node connection information to the transmission right. , The bus occupancy can be made more efficient.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle data transmission system according to the present invention will be described below with reference to the drawings.

FIG. 1 shows a configuration diagram of an embodiment of the vehicle data transmission system of the present invention. In the vehicle transmission system shown in FIG. 1, an engine control node 1a, a mission control node 1b, a brake control node 1c, a suspension control node 1d, and an output torque control node 1e are connected to a bus 3 in the network. Necessary data is transmitted and received between each other.

That is, the transmission right is circulated among the nodes 1a to 1e in a predetermined order, and the node which has acquired the transmission right sends the data to the bus 3.

It should be noted that the first control node 1f, the second control node 1g, and the third control node 1h exist without being connected to the bus 3.

The engine control node 1a controls the operation of the engine according to the driver's operation of the accelerator pedal or the like. The mission control node 1b controls the automatic transmission according to the driving state of the vehicle.

The brake control node 1c performs brake control by detecting the locked state of the wheels. The suspension control node 1d controls the suspension according to the driving state of the vehicle. Output torque control node 1
e detects the slip state of the drive wheels of the vehicle and controls the output torque of the engine.

The engine control node 1a includes a CPU (central processing node) 11a, a transmission / reception unit 21a, a transfer destination setting unit 2
3a, a memory 25a, an address management table 30a, and an address comparison unit 32a.

The engine control node 1a is connected to sensors 31a, actuators 41a, and diagnostic testers 5 which are provided in various parts of the vehicle and detect a running state.

Although only one sensor 31a is shown in FIG. 1, it is assumed that a plurality of sensors 31a are actually provided. The CPU 11a drives the actuator 41a based on a detection signal from the sensor 31a.

The diagnostic tester 5 transfers the node address, which is the node connection information indicating the node currently connected to the bus 3, to the engine control node 1a, which is the master node, by diagnostic communication.

The memory 25a stores transmission data. The delegation destination setting unit 23a sets the delegation destination node of the transmission right by the address of the delegation destination node, and sets the delegation destination node by incrementing the address of the delegation destination node.

Transmission / reception unit 2 of the engine control node 1a
1a sends the node connection information stored in the address management table 30a described later to all the control nodes 1b, 1c, 1d, 1e connected to the bus 3.

When a node connected to the bus 3 is changed by addition or reduction, the transmission / reception unit 21a of the engine control node 1a transmits the changed node connection information at that time to all the nodes connected to the bus 3. To the control node.

The address management table 30a stores node connection information indicating all the nodes 1a to 1e connected to the bus 3, and is provided in a nonvolatile memory in the engine control node 1a.

FIG. 3 shows the contents of the address management table 30a. Address management table 30a shown in FIG.
Are the node addresses "1a, 1" of the engine control node 1a, the mission control node 1b, the brake control node 1c, the suspension control node 1d, and the output torque control node 1e connected to the bus 3 as node connection information.
b, 1c, 1d, 1e "are stored.

In this case, the first to third control nodes 1f to 1h are nodes that are not currently connected to the bus 3.

The address management table 3 shown in FIG.
0a is an engine control node 1a, a mission control node 1b, a brake control node 1c, a suspension control node 1 connected to the bus 3 as node connection information.
d, the node address "1a, 1" of the output torque control node 1e and the third control node 1h additionally connected to the bus 3.
b, 1c, 1d, 1e, 1h "is stored.

In this case, the first and second control nodes 1f and 1g are nodes that are not currently connected to the bus 3.

The address comparing unit 32a compares the node connection information indicating the transfer destination node set by the transfer destination setting unit 23a with the node connection information stored in the address management table 30a.

The delegation destination setting unit 23a increments the delegation destination node, and when the node connection information indicating the delegation destination node matches the node connection information stored in the address management table 30a, indicates the matched node connection information. Set the node as the node to which the transmission right is delegated.

The transmission / reception section 21a is provided with the transfer destination setting section 23
The transmission right delegation message is transmitted to the transmission right delegation destination node set by a.

The transmission control node 1b, the brake control node 1c, the suspension control node 1d, and the output torque control node 1e are also the engine control node 1b.
The configuration is almost the same as the configuration a.

However, the diagnostic tester 5 is not connected to the control nodes 1b to 1e. According to the node connection information from the master engine control node 1a, the slave control nodes 1b to 1e create the address management table 30a.

FIG. 2 shows the format of a data frame according to the embodiment. In FIG. 2, the data frame includes an SOM indicating the start of a message, a transfer destination address indicating an address of a transfer right transfer destination node, a transmission source address, data, an error detection character string CRC, reception acknowledgment information, and an end of the message. EOM shown.

The transfer destination address may be set to a value of 0 to 5 corresponding to each of the control nodes.

The data includes a data byte length, a data identifier, and information to be transmitted. The reception acknowledgment information includes reception acknowledgment information from a node that has successfully received data and reception acknowledgment information from a node that has normally received a transmission right. The transfer destination address is obtained from the transfer destination setting unit 23a.

Next, the operation of the embodiment configured as described above will be described with reference to the flowchart shown in FIG. Here, for example, it is assumed that the transmission right circulates in the order of the engine control node 1a, the mission control node 1b, the brake control node 1c, the suspension control node 1d, and the output torque control node 1e.

First, the diagnostic tester 5 sends the node addresses "1a, 1b," which are node connection information indicating the node currently connected to the bus 3, to the engine control node 1a.
Then, the engine control node 1a creates an address management table 30a storing the node addresses "1a, 1b, 1c, 1d, 1e" as shown in FIG. Is done.

Next, the transmission / reception unit 21a of the engine control node 1a sends the node address stored in the address management table 30a to all the control nodes 1b, 1c, 1d, 1e connected to the bus 3.

Then, also in the control nodes 1b to 1e, the address management table 30a is created.

Next, the output torque control node 1e is
In the data frame shown in (1), the transfer destination address is "1a (address of the engine control node)" and the source address is "1e
(The address of the output torque control node) ", and transfers it to the engine control node 1a.

Then, the transmission / reception unit 21a of the engine control node 1a sends the transmission transfer destination message (here, the transfer destination address “1”) from the output torque control node 1e.
a ″) is determined (step 1).
1).

The engine control node 1a receives the transfer destination address "1a" and the source address "1e" and obtains the transmission right. Then, the delegation destination setting unit 23a in the engine control node 1a sets the delegation destination address to the next delegation destination address.
1b (the address of the mission control node) "(step S13).

The address comparing section 32a is provided with the transfer destination setting section 2
It is determined whether the address value of the next delegation destination node set in 3a matches the node address value stored in the address management table 30a (step S15).

If the address value of the next delegation destination node does not match the node address value stored in the address management table 30a, the process returns to step S13, and the delegation destination setting unit 23a continues until the two address values match. , The address value of the transfer destination node is incremented.

When the address value of the delegation destination node matches the node address value stored in the address management table 30a, the delegation destination setting unit 23a sets the matched address value as the transmission delegation destination address ( Step S17).

Next, the transmission / reception section 21a of the engine control node 1a determines whether the transmission data has been set in the transmission buffer (not shown) (step S19).

When the transmission data has been set in the transmission buffer, the transmission delegation message is transmitted to the transmission delegation node indicated by the transmission delegation address obtained in step 17 (step S21).

Then, the transmission delegation node indicated by the transmission delegation address obtains the transmission right. In the example shown in FIG. 1, the delegation destination setting unit 23a sets the next control node 1b for its own node 1a, and this control node 1b exists in the address management table 30a.

For this reason, the transmission / reception unit 21a of the engine control node 1a sends the transmission delegation destination message to the mission control node 1b as the transmission delegation destination node, and the transmission right is acquired by the mission control node 1b.

Since the mission control node 1b sends the transmission delegation message to the brake control node 1c as the transmission delegation node with reference to the address management table 30a, the brake control node 1c obtains the transmission right. Become.

Similarly, the other nodes refer to the address management table 30a to determine the transmission destination node.

Further, it is determined whether or not the processing is completed (step S23). If the processing is not completed, the process returns to step S11.

On the other hand, if the own node does not receive the transmission transfer destination message from the output torque control node 1e in step 11, the necessary data is stored in the memory 25a such as a RAM (step S25).

As described above, in the vehicle data transmission system adopting the token passing method, the node control information indicating all the nodes connected to the bus 3 by the master engine control node 1 a is connected to the bus 3. Is sent to all nodes.

Then, all the other nodes determine the necessary transmission partner node based on the node connection information and the transmission order and transmit the transmission data, so that the transmission delegation destination message does not need to be transmitted on the bus 3. Stop transferring. Therefore, the efficiency of the bus occupancy of each node on the network can be improved.

Further, for example, when the third control node 1h shown in FIG. 1 is additionally connected to the bus 3, the diagnostic tester 5 outputs the node address "1h" which is the node connection information indicating the third control node 1h. "To the engine control node 1
a.

Then, as shown in FIG. 3B, the node addresses “1a, 1b, 1c, 1” which are the node connection information.
d, 1e, 1h "
a is created.

The transmission / reception unit 21a of the engine control node 1a transmits the node address "1a," which is the node connection information stored in the address management table 30a.
1b, 1c, 1d, 1e, and 1h "to all the control nodes 1b, 1c, 1d, 1e, and 1h connected to the bus 3. The address management table 30a is also stored in the control nodes 1b to 1h. Created.

Therefore, each node connected to the bus 3
The transmission destination node is determined based on the node connection information and the transmission order in the address management table 30a.

Further, another control node may be additionally connected to the bus 3. Conversely, a certain node may be separated from the bus 3. in this way,
When a node is changed by adding or decreasing, the contents of the address management table 30a may be rewritten according to the change.

For example, when the mission control node 1b is disconnected from the bus 3, the address management table 3
The node address of 0a is “1a, 1c, 1d, 1e,
1h ".

In this case, the delegation destination setting unit 23a of the engine control node 1a sets the next mission control node 1b for its own node 1a, because this mission control node 1b is not in the address management table 30a. Is incremented, and the next brake control node 1c is set.

The brake control node 1c exists in the address management table 30a. Therefore, the transmission / reception unit 21a of the engine control node 1a sends the transmission delegation destination message to the brake control node 1c as the transmission delegation destination node, so that the brake control node 1c acquires the transmission right.

[0084]

According to the present invention, the storage means stores the node connection information indicating all the nodes connected to the bus, and the transfer destination setting means refers to the node connection information stored in the storage means. Then, the transmission right delegation node is set, and the transmission / reception means sends the transmission right delegation message to the transmission right delegation node set by the delegation destination setting means.

That is, since the transmission delegation destination message is transferred only to the node currently connected to the bus, the efficiency of the bus occupancy can be improved.

Also, one of the plurality of nodes sends the node connection information to all nodes, so that all nodes may determine the transmission delegation destination node with reference to the node connection information. it can.

Further, one of the plurality of nodes sends the changed node connection information at that time to all the nodes when the node connected to the bus is changed due to addition or reduction. The transmission delegation destination node can be determined according to the changed node connection information, and the bus occupancy can be made more efficient.

Further, the judging means judges whether or not the node connection information indicating the delegation destination node set by the delegation destination setting means matches the node connection information stored in the storage means. When the delegation destination node is incremented and the node connection information indicating the delegation destination node matches the node connection information stored in the storage unit, the node indicating the matched node connection information is set as the transmission right delegation destination node. The efficiency of the bus occupancy can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a vehicle data transmission system of the present invention.

FIG. 2 is a diagram showing a format of a data frame.

FIG. 3 is a diagram showing an address management table.

FIG. 4 is a flowchart showing the operation of the embodiment of the vehicle data transmission system of the present invention.

FIG. 5 is a flowchart illustrating a network abnormality determination of a conventional vehicle data transmission system.

FIG. 6 is a flowchart showing a conventional data transmission / reception between vehicles.

[Explanation of symbols]

 1a Engine control node 1b Mission control node 1c Brake control node 1d Suspension control node 1e Output torque control node 1f First control node 1g Second control node 1h Third control node 3 Bus 5 Diag tester 11a CPU 21a Transmitter / receiver 23a Delegation destination setting unit 25a Memory 30a Address management table 31a Sensor 32a Address comparison unit 41a Actuator

Claims (4)

[Claims] 1. A vehicle data transmission system in which a plurality of nodes are connected to a bus, a transmission right is circulated among the nodes in a predetermined order, and a node having acquired the transmission right sends data to the bus. A storage unit for storing node connection information indicating all nodes connected to the bus; and a node to which the transmission right is delegated with reference to the node connection information stored in the storage unit. A vehicle data transmission system comprising: a delegation destination setting unit that transmits a transmission right delegation message to the transmission right delegation destination node set by the delegation destination setting unit. 2. The vehicle data transmission system according to claim 1, wherein one of the plurality of nodes sends the node connection information to all nodes. 3. One of the plurality of nodes, when a node connected to the bus changes due to addition or reduction, sends the changed node connection information at that time to all nodes. The vehicle data transmission system according to claim 2, wherein: 4. A method according to claim 1, further comprising: a determination unit configured to determine whether node connection information indicating the delegation destination node set by the delegation destination setting unit matches the node connection information stored in the storage unit. The means increments the delegation destination node, and when the node connection information indicating the delegation destination node matches the node connection information stored in the storage means, sets the node indicating the matched node connection information to the transmission right delegation destination node. The vehicle data transmission system according to any one of claims 1 to 3, wherein the vehicle data transmission system is set to: