JP3265739B2 - Multiplex transmission equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a plurality of terminal nodes
The present invention relates to a multiplex transmission device connected to at least one common transmission path.

[0002]

2. Description of the Related Art Conventionally, in a multiplex transmission apparatus of this kind, FIG.
As shown in FIG. 3, among the transmission lines (main lines) 10 and 11, a first bias device 21 for biasing the first transmission line 10 to the power supply side potential and a second biasing device 21 for biasing the second transmission line 11 to the ground side potential. A plurality of first terminal nodes 20 to 20 having a second bias device 22 for performing communication control of data and a plurality of first terminal nodes 20 to 20 having a communication control device 31 for performing communication control of the data. 2 terminal nodes 30-
30 are connected via the common transmission lines 10 and 11 described above. Further, the first bias device 21 and the communication control device 23 are connected to the transmission line 10 via the branch line 12,
The second bias device 22 and the communication control device 23 communicate with the transmission line 11 via the branch line 13 and the communication control device 31.
Are connected to the transmission lines 10 and 11 via branch lines 14 and 15, respectively, and the terminal nodes 20 to 20, 30 to
Reference numeral 30 performs data transmission with each other via the common transmission paths 10 and 11.

In such a multiplex transmission apparatus, the terminal node 2
0 (30) is a branch line 12 (1) corresponding to the joint connector 9 and each of the transmission lines 10 and 11, as shown in FIG.
4), 13 (15), because it is connected to the transmission lines 10, 11, when one of the branch lines is disconnected,
When the disconnected terminal node transmits and receives data, the data transmission performed by the communication control device of the terminal node is a one-sided transmission because the connection with the transmission path is disconnected.

[0004]

However, in the multiplex transmission apparatus, when the disconnected terminal node is a terminal node having a bias device and transmits / receives data to / from the terminal node, the data is transmitted in the same manner as described above. There is a problem that the transmission becomes one-sided transmission and a double failure including a bias deviation occurs. In addition, since the connection between the transmission line and the terminal node is mutually connected via a joint connector and a branch line, there are many connection points, and a terminal node having an impedance characteristic having a bias device and a terminal node having no bias device. However, there is also a problem that a reflected wave is generated in the transmission waveform. In the above-described conventional example, the case where the transmission path is connected in a loop type has been described. However, the present invention is not limited to this, and there is a similar problem when the transmission path is connected in a bus type, for example.

The present invention has been made in view of the above problems, and prevents a double failure even if a transmission line is disconnected.
It is an object of the present invention to provide a multiplex transmission device that can improve reliability during data transmission.

[0006]

To achieve the above object, according to an aspect of, the claims 1, 3, 2 and a common transmission path, and a communication control means for controlling the data transmission, respectively Bei present invention
E is connected to the transmission line comprises first and second plurality of end nodes performing multiplex transmission via the transmission path, the first terminal node, via one transmission path to the supply-side potential
And the other transmission line is grounded.
A second bias means for biasing to the side potential;
The bias means and the communication control means are connected to the transmission path 2
Multiplexing transmission device with connection means for connecting to each
Device is provided. In claims 2 and 3, the first terminal
The connection between the bias means and the communication control means.
Connection means for connecting to different parts of the transmission path
And a multiplex transmission device including Claim
In No. 4, a multiplex transmission apparatus in which a power line is arranged along a transmission line is provided.

[0007]

The connection terminal is ## acts] connecting means, the communication control device is a biasing device and the communication control means is a biasing means of the terminal node, two places in each transmission path without via the branch line
To connect. Therefore, even when a fault such as one is disconnected transmission path occurs, the connection of the bias unit and the communication control device is made, on one side transmission and double faults bias off disappears in several places (claim
1, 3). Also, each bias means of the first terminal node
Communication control means are located on different parts of the transmission path.
Connection, so one-sided transmission and double bias
Obstacles are eliminated (claims 2 and 3). Further, the Rukoto placed along the power line to the transmission line, it is also possible to lower the noise level emitted by the multiplex transmission apparatus.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described with reference to FIGS. In the multiplex transmission apparatus embodying the present invention, the connection method of the transmission path may be, for example, a loop type or a bus type. However, since the components of the apparatus are almost the same, in this embodiment, the loop type is typically used. The case will be described.

FIGS. 1 and 2 are block diagrams showing an embodiment of the configuration of a terminal node according to the present invention. FIG. 1 shows a case of a terminal node having a bias device, and FIG. This is the case of a terminal node having no terminal node. In FIG. 1, a terminal node 40 having a bias device includes a first bias device 41 for biasing the first transmission line 10 to a power supply side potential and a second bias device for biasing the second transmission line 11 to a ground side potential. A bias device 42 and a communication control device 43 for controlling the data communication by changing the voltage of each of the transmission lines 10 and 11 according to the dominant or passive state.
Connection terminals 44 and 45 for connecting the first bias device 41 and the communication control device 43 to the first transmission line 10 at two locations; and the second bias device 42 and the communication control device 43. Are connected to the second transmission line 11 at two locations. The transmission lines 10 and 11 and the terminal node 40 are connected by a daisy chain connection.

In FIG. 2, a terminal node 50 having no bias device is provided with a communication control device 51 having the same function as the communication control device 43 shown in FIG. Connection terminals 52 and 53 for connecting to the transmission line 10 and connection terminals 54 and 5 for connecting the communication control device 51 to the second transmission line 11 at two locations.
And 5. In addition, the transmission lines 10 and 11
And the terminal node 50 are connected by a daisy chain connection, and the transmission lines 10 and 11 are respectively connected in a loop type.

The connection terminals shown in FIGS. 1 and 2 can be provided at two or more locations on the same transmission line. Also,
The terminal node having the bias device is, for example, as shown in the terminal node 60 of FIG.
A first bias device 61 for biasing the power supply to the power supply side potential,
A second bias for biasing the second transmission line 11 to the ground side potential
The bias device 62 and the communication control device 63 for controlling data communication are separately and independently provided, respectively.
It is also possible to provide one or more connection terminals 64 to 67 for connection to the respective transmission paths 10 and 11 via. The wiring between each device in the terminal node and the connection terminal can be realized by, for example, a printed circuit board.

FIGS. 4 and 5 show another embodiment of the terminal node 40, and FIGS. 6 and 7 are block diagrams showing another embodiment of the terminal node 50. FIG. 4 and 6, the transmission lines 10 and 11 and the terminal nodes 40 and 50 are daisy-chain connected in the terminal nodes 40 and 50 via connectors 48 and 56. 5 and 7, the terminal nodes 40 and 50 are connected by four connection terminals 44a to 47a and 52a to 55a,
In addition, in the connectors 48, 56, the transmission lines 10, 11
And terminal nodes 40 and 50 are connected in a daisy chain, so that connectors 48 and 56 and terminal nodes 40 and 50 are connected.
Even if 50 is disconnected, simultaneous disconnection of the transmission lines 10 and 11 can be prevented.

Next, a first embodiment of the configuration of the multiplex transmission apparatus according to the present invention is shown in FIG. In the figure, each terminal node 40 having a bias device (see FIG. 1) and each terminal node 50 having no bias device (see FIG. 2) are daisy-chain connected to two transmission lines 10 and 11, respectively. I have. That is, in each terminal node 40 having a bias device, both the bias devices 41 and 42 and the communication control device 43 connect the transmission lines 10 and 11 via the connection terminals 44 to 47.
Are daisy-chained at two locations.
In each terminal node 50 having no bias device,
The communication control device 51 is daisy-chain connected to the transmission lines 10 and 11 at two locations via the connection terminals 52 to 55.

Therefore, in this embodiment, a fault occurs such that one of the transmission lines near the terminal node 40 having the bias device is disconnected, for example, the position of the cross mark of the transmission line 10 shown in FIG. 8 is disconnected. Also has no branch lines and the terminal node 40
Since the first bias device 41 is connected to the transmission line 10 via the connection terminal 44, the bias is not lost or one-side transmission is not performed, and the terminal node 40 transmits data favorably to each of the other terminal nodes in the device. It can be performed. Further, in the present embodiment, the transmission path is formed in a daisy chain connection with a loop type, and the number of branch lines is reduced, so that a reflected wave is not easily generated in the transmission waveform. Further, in this embodiment, the transmission line and the terminal node are directly connected by the daisy chain connection method without using the joint connector, so that the number of connection points is four, and the conventional connection method shown in FIG. In this case, the number of connection points can be reduced.

When the transmission line is connected in a loop type as in this embodiment, even if only one terminal node 40 having a bias device exists in the multiplex transmission device, the transmission line is disconnected. Occasionally, double faults in which one-sided transmission and debiasing occur simultaneously can be prevented. In the case where the transmission line is connected in a bus type, as shown in the second embodiment of FIG. 9, a terminal node having a bias device to prevent a double failure from occurring when the transmission line is disconnected. It is necessary to provide two or more nodes 40 in the multiplex transmission apparatus, and to arrange the terminal nodes 40 at both ends of the transmission line. This is the same in the case where the embodiments described below are applied to a bus type. As a result, even if a disconnection occurs in any part of the transmission line, it is possible to prevent a double failure in which the one-side transmission and the bias release occur simultaneously.

For a terminal node having no bias device, a connection method other than the daisy chain connection described above may be used, for example, a conventional connection method via a branch line may be used. FIG. 10 is a diagram showing a third embodiment of the configuration of the multiplex transmission apparatus according to the present invention. In the figure, each terminal node 60 having a bias device (see FIG. 3) and each terminal node 30 having no bias device (see FIG. 14)
Two transmission lines 10, 11 and branch lines 16 to 19 and branch line 1
Each terminal node 50 (see FIG. 2), which is connected via the transmission lines 4 and 15 and has no bias device, is daisy-chain connected to the two transmission lines 10 and 11, respectively. That is, each terminal node 60 having a bias device
Then, the bias device 6 is connected via the connection terminals 64-67.
1 and 62 and the communication control device 63 are separately and independently connected to the transmission lines 10 and 11, respectively.

Therefore, in this embodiment, even if a fault occurs such that one of the branch lines of the terminal node 60 having the bias device is broken, the double failure is eliminated, and the terminal node 60 is connected to each of the other terminals in the device. Data transmission with the node can be performed well. In the above embodiment, the bias device is provided in each terminal node and connected to each transmission line. However, the present invention is not limited to this. For example, as shown in the fourth embodiment in FIG. Biasing devices 71 and 81 for biasing the transmission line 10 to the power supply side potential and the second transmission line 1
The second bias devices 72 and 82 for biasing 1 to the ground side potential are independently provided, and nodes 70 and 80 including only the bias devices are provided. The nodes 70 and 80 are connected to the two transmission lines 10 and 11 respectively. Daisy chain connection,
Alternatively, the connection can be made via a branch line. Also,
As shown in the fifth embodiment of FIG.
Power supply lines 91 and 92 for supplying power from the power supply device 90 to the power supply lines 40 and 50 can be wired along the transmission lines 10 and 11. In this case, a wire harness can be achieved, and a current loop between the transmission line and the power supply line is reduced, so that the noise level radiated from the multiplex transmission device can be reduced, and other electronic devices can be reduced. Impact on the vehicle can be reduced.

[0018]

As described above, as described above, the multiple transmission of the present invention is performed.
Feeding device, two a common transmission path, is connected a communication control means for controlling the data transmission to the transmission path with each
The first and second plurality of Te performing multiplex transmission via the transmission path
2. The first terminal node according to claim 1, wherein the first terminal node biases one of the transmission lines to a power supply side potential.
1 bias means and the other transmission path to ground side potential
Second bias means for biasing, and each of these biases
Means and said communication control means at two locations on said transmission path.
And connection means for connecting each of them.
The first terminal node is connected to each of the bias means and the communication control.
Control means to different parts of the transmission line.
Connection means to prevent double failures such as one-sided transmission and out-of-bias even if a disconnection occurs in any part of the transmission line, and to improve reliability during data transmission.
This makes it difficult for reflected waves to occur in the transmission waveform. In addition, since the current loop between the power line and the transmission line is reduced by arranging the power line that supplies power to the terminal node along the transmission line, the noise level radiated from the multiplex transmission device can be reduced. Thus, the influence on other electronic devices can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a configuration of a terminal node according to the present invention.

FIG. 2 is a block diagram showing another embodiment of the configuration of the terminal node according to the present invention.

FIG. 3 is a block diagram showing another embodiment of the configuration of the terminal node according to the present invention.

FIG. 4 is a block diagram showing another embodiment of the configuration of the terminal node according to the present invention.

FIG. 5 is a block diagram showing another embodiment of the configuration of the terminal node according to the present invention.

FIG. 6 is a block diagram showing another embodiment of the configuration of the terminal node according to the present invention.

FIG. 7 is a block diagram showing another embodiment of the configuration of the terminal node according to the present invention.

FIG. 8 is a diagram showing a first embodiment of the configuration of the multiplex transmission apparatus according to the present invention.

FIG. 9 is a diagram showing a second embodiment of the configuration of the multiplex transmission apparatus according to the present invention.

FIG. 10 is a diagram showing a third embodiment of the configuration of the multiplex transmission apparatus according to the present invention.

FIG. 11 is a diagram showing a fourth embodiment of the configuration of the multiplex transmission apparatus according to the present invention.

FIG. 12 is a diagram showing a fifth embodiment of the configuration of the multiplex transmission apparatus according to the present invention.

FIG. 13 is a diagram showing a configuration of a conventional multiplex transmission device.

FIG. 14 is a diagram illustrating a conventional connection method between a transmission path and a terminal node.

[Explanation of symbols]

10, 11 transmission line 12 to 19 branch line 20 to 80 node 21, 22, 41, 42, 61 to 81, 62 to 82 bias device 23, 31, 43, 51, 63 communication control device 44 to 47, 52 to 55, 44a-47a, 52a-5
5a, 64 to 67 connection terminal 90 power supply device 91, 92 power supply line

Continuation of front page (72) Inventor Yusaku Hinoki 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (56) References JP-A-64-50727 (JP, A) JP-A-59- 107670 (JP, A) Japanese Utility Model Showa 59-81650 (JP, U) Japanese Utility Model Showa 63-131436 (JP, U) Japanese Utility Model Utility Model No. 2-16628 (JP, U) (58) Field surveyed (Int. ⁷ , DB name) H04L 12/437 H04L 25/02

Claims (4)

(57) [Claims] 1. A connecting two a common transmission path, and a communication control means for controlling the data transmission to the transmission path with each
It has been the transmission path through and multiplex transmission is carried out in the first and second
A plurality of terminal nodes, wherein the first terminal node sets one of the transmission paths to a power supply side potential.
The first biasing means for biasing and the other transmission path are grouped.
Second bias means for biasing to a land side potential;
Transmitting each of the bias means and the communication control means to the
A multiplex transmission device comprising: connection means for connecting to two places on a road . 2. A connecting two a common transmission path, and a communication control means for controlling the data transmission to the transmission path with each
It has been the transmission path through and multiplex transmission is carried out in the first and second
A plurality of terminal nodes, wherein the first terminal node communicates with each of the bias means.
Communication control means at different portions of the transmission path.
A multiplex transmission device comprising a connection means for connecting the connection . 3. The multiplex transmission apparatus according to claim 1, wherein said second terminal node includes connection means for connecting said communication control means to two points on said transmission line. Wherein said first and second terminal nodes are connected to the power supply line of the power supply, the power supply line, characterized in der Rukoto that is wired along a said transmission path The multiplex transmission device according to claim 1.