JPH0558232A - Multiple transmission device - Google Patents

Abstract

PURPOSE:To simplify the constitution of each means and circuit and achieve cost cut by installing a means for starting each communication node, means for forming the ON/OFF signal for each starting means, and a means for the transmission of the ON/OFF signal to each starting means, in a plurality of communication nodes. CONSTITUTION:A microcomputer 1, multiple module 2 which is connected with the microcomputer 1 and inputs and outputs control signals as multiple signals, and a wake-up circuit (starting means and starting signal formation means) 3 which is connected with the microcomputer 1 and wakes up (starts) the microcomputer 1 are installed in a communication node A. Other communication nodes B and C are constituted in similar manners. Each multiple module 2 in a plurality of communication nodes A-C is connected each other through the multiple transmission passages 4 and 41 consisting of the twist pair lines, and each wake-up circuit 3 is connected each other through the wake-up lines (transmission lines) 5 and 51. Accordingly, starting (wake-up) is enabled by the simple ON/OFF signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiplex transmission device for connecting a plurality of communication nodes to one transmission line and performing multiplex transmission of data by frequency control or time division method.

[0002]

2. Description of the Related Art In recent years, the number of electronic components such as switches, sensors and actuators has been increased in automobiles, and the wiring harnesses connecting the electrical components have become large and complicated. This is becoming a problem, and in order to solve this problem, for example, JP-A-62
As described in Japanese Patent Publication No. 4658, a multiplex transmission method in which a transmission line is shared by a large number of electrical components is adopted, a communication node including various operation switches and display devices, an air conditioner,
Audio equipment, engine control (EGI), four-wheel steering control (4WS), anti-lock brake control (ABS) and other control system communication nodes each have multiple modules and are connected to multiple transmission lines to perform multiple communication. It is known that a system is constructed.

In the above multiplex communication system, in order to prevent power consumption of the battery, each communication node is put into a sleep state, that is, inactive state when the ignition key is removed, and the multiplex module consuming a large amount of power is not energized. When the ignition key is inserted and turned on, a wake-up signal is issued by a multiplex communication signal via a multiplex transmission line to wake up or activate each communication node to energize the multiplex module and enter an operation standby state.

[0004]

However, in the conventional multiplex communication system described above, it is necessary to provide each communication node with a detection circuit for reading a wake-up signal from the multiplex communication signal. There is a problem that the circuit configuration of is complicated and the cost is increased.

An object of the present invention is to provide a wake-up dedicated circuit for transmitting a wake-up signal and a wake-up dedicated line for transmitting a wake-up signal separately, thereby simplifying the circuit configuration of each communication node and reducing the cost. It is an object of the present invention to provide a multiplex transmission device that can be downsized.

[0006]

In the multiplex transmission apparatus of the present invention, a plurality of communication nodes are connected via multiplex transmission lines,
A multiplex transmission device for transmitting and receiving control signals and the like between each communication node via a multiplex transmission path, which is provided in each communication node and is an activation means (wakeup dedicated circuit) for activating (wakeup) each communication node. And a signal forming means (wakeup dedicated circuit) for forming an on / off signal (wakeup signal) for activating each activating means, and a transmission path (wakeup dedicated line) for transmitting the on / off signal to each activating means ) And can be activated (wake up) by a simple on / off signal, the configuration of the activation means and the signal forming means is simplified, the circuit configuration of each communication node is simplified, and the cost is reduced. Can be planned.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1, a communication node A includes a microcomputer 1, a multiplexing module 2 connected to the microcomputer 1 for inputting and outputting a control signal as a multiplexed signal, and a microcomputer connected to the microcomputer 1. A dedicated wake-up circuit (starting means and signal forming means) 3 for waking up (starting) 1 is provided, and the other communication nodes B and C have the same configuration.

The multiple modules 2 in the plurality of communication nodes A, B, C, ... Are connected to each other via multiple transmission lines 4, 41 ,. 3 are connected to each other through dedicated wakeup lines (transmission paths) 5, 51, ....

The dedicated wake-up circuit 3 includes a transistor 31, and the collector of the transistor 31 is connected to the dedicated wake-up line 5, the input side of the guarantee circuit 32, and the power supply (+ B) via the resistor 33 to ensure the guarantee. The output side of the circuit 32 is connected to the wakeup signal input port of the microcomputer 1, the base of the transistor 31 is connected to the wakeup signal output port of the microcomputer 1 via the resistor 34, and the emitter of the transistor 31 is grounded. , And is connected to the wired OR between the plurality of communication nodes A, B, C, .... The microcomputer 1 is also grounded via a switch 6 such as an ignition switch.

The guarantee circuit 32 includes a power supply control circuit that holds the power supply voltage at a predetermined value, a protection circuit that protects the microcomputer 1 in the event of a short circuit, an interrupt signal generation circuit that starts the microcomputer 1 from a low current mode, and the like. It is a circuit for operating the microcomputer 1 without fail.

As shown in the time chart of FIG.
In the sleep state in which the multiple modules are not energized, the collector voltage of the transistor 31, that is, the voltage applied to the wake-up dedicated line 5 has a predetermined value Hi.
When the switch 6 of the communication node A is turned on, the communication node A wakes up and the voltage applied from the output port of the microcomputer 1 to the base of the transistor 31 rises to a predetermined level. The transistor 31 is turned on with a time delay, the collector voltage of the transistor 31 drops, and the voltage of the dedicated wake-up line 5 increases as the collector voltage of the transistor 31 drops.
It drops to Lo (for example, 0V) and issues a wake-up signal.

A case where another communication node receives a wakeup signal will be described. A voltage drop signal, that is, a wakeup signal is input to the input port of the microcomputer 1 through the guarantee circuit 32 of the dedicated wakeup circuit 3 in the communication node B. When input, the communication node B wakes up with a predetermined time delay, and the voltage of the dedicated wakeup line 51 drops, so the communication node C
The voltage drop signal (wakeup signal) is input to the input port of the microcomputer 1 via the guarantee circuit 32 of the dedicated wakeup circuit 3 in FIG. 1, the communication node C wakes up with a predetermined time delay, and the communication node C In the case of only three communication nodes B and C, the wake-up operation is completed when the communication node C wakes up as shown in the figure. When the communication nodes B and C wake up, both communication nodes B and C The voltage applied from the output port of the microcomputer 1 to the base of the transistor 31 rises and the transistor 31 turns on. When there are three or more communication nodes shown in the figure, a plurality of communication nodes connected in the same manner are waked up.

Each waked-up communication node performs a normal operation, and enters a sleep state when the normal operation ends. For example, the communication node A completes all normal operations and enters a sleep state. When the state becomes good, the voltage applied from the output port of the microcomputer 1 to the base of the transistor 31 drops, the transistor 31 turns off, and the preparation for entering the sleep state is completed. Communication node A when other communication nodes B and C are in operation
Is also in an operation standby state, both communication nodes B and C are in a state in which normal operation is completed and it is possible to enter a sleep state, and the voltage applied to the base of the transistor 31 from the output port of each microcomputer 1 drops. Then, when the transistor 31 is turned off and the preparation for entering the sleep state is completed, the collector voltage of the transistor 31 of the communication nodes A, B, C rises, the voltage of the wake-up dedicated line 51 rises, and all the communication nodes A, After confirming that B and C are in a state where they can enter the sleep state, all communication nodes A,
B and C go to sleep.

An example of the multiplex transmission device having the wake-up system will be described with reference to FIG. 3. The door switch 11A and the memory pattern switch 12A for inputting a signal for operating the power seat in a predetermined pattern are input side. In addition, a total wiring system (T which has a headlight relay 13A for turning on / off the headlight and a horn relay 14A for operating the horn) is connected to the output side.
WS) 1A (corresponding to the communication node A, for example)
, Headlight switch 11B, horn switch 12B
Is an input side, a meter 1B (for example, corresponding to the communication node B) to which the half-door warning lamp 13B is connected to the output side, and a motor relay 11C for controlling the motor for adjusting the seat pattern on the output side. With the connected power sheet 1C (e.g., corresponding to the communication node C),
The door switch 11 is connected by a multiplex transmission line 40 consisting of twisted pair lines and a dedicated wake-up line 50.
When the A or memory pattern switch 12A is turned on, the TWS 1A wakes up and sends a wakeup signal to the meter 1B and the power seat 1C to wake up, and either the headlight switch 11B or the horn switch 12B. When the switch of is turned on, the meter 1B wakes up,
Send wake-up signal to TWS1A and power seat 1C
Call to wake up.

Next, the wake-up system constructed by connecting the diodes in a wired OR connection in FIG. 4 will be described. Each communication node 2A, 2B, 2C is connected to the microcomputers 21A, 21B, 21C and the microcomputer. And multiple modules 22A, 22B, 22C, and multiple modules for the communication nodes 2A, 2B, 2C
22A, 22B and 22C are connected to each other by a multiplex transmission line 400 and perform multiplex communication of various control signals and the like.

Guarantee circuits 23A, 23B, and 23C are provided on the input sides of the microcomputers 21A, 21B, and 21C, respectively, and two are provided each.
Diodes 24A, 25A; 24B, 25B; 24C, 25C
And a wake-up switch with one terminal grounded
26A, 26B and 26C are connected in series, and the midpoints 27A, 27B and 27C of the two diodes 24A and 25A; 24B and 25B; 24C and 25C are connected by a wake-up dedicated line 500.

Explaining the wake-up operation,
When the wake-up switch 26A is turned on, the potential at the midpoint 27A of the diodes 24A and 25A decreases (eg, 0
V) and input the wake-up signal to the microcomputer 21A of the communication node 2A to input the microcomputer 21A.
A wakes up the other communication node 2
B, 2C diodes 24B, 25B; midpoint between 24C, 25C
The potentials of 27B and 27C are lowered, and a wakeup signal is input to the microcomputers 21B and 21C to wake up.

The wake-up operation will be described with reference to the flowchart of FIG. 5. When the system of the multiplex transmission device is activated (wake-up), if the wake-up switch 6 of the communication node A is on, The communication node A is waked up, the wakeup transistor 31 is turned on, and a wakeup signal is transmitted from the dedicated wakeup lines 5 and 51 to the other communication nodes B and C to wake up the communication nodes B and C, respectively. , The wake-up transistors 31 of the communication nodes B and C are turned on to start normal operation.

When the wakeup switch 6 of the communication node A is off and the wakeup switch 6 of the communication node B is on, the communication node B is waked up and the wakeup transistor 31 is turned on. The communication nodes A and C are turned on and a wakeup signal is transmitted from the dedicated wakeup lines 5 and 51 to the other communication nodes A and C to wake up the communication nodes A and C, respectively.
The wake-up transistors 31 are turned on to start normal operation.

When the wakeup switch 6 of the communication nodes A and B is off, the wakeup switch 6 of the communication node C should be on.
The communication node C is waked up, the wakeup transistor 31 is turned on, and a wakeup signal is transmitted from the dedicated wakeup lines 5 and 51 to the other communication nodes A and B to wake up the communication nodes A and B, respectively. , Wake-up transistor of communication nodes A and B
Turn on 31 respectively to start normal operation.

After the normal operation is completed, when the preparation for entering the sleep state is completed in each communication node A, B, C, the voltage applied to the base of the transistor 31 of each communication node A, B, C drops and the transistor 31 turns off, and confirms that all communication nodes A, B, and C are in a state in which they can enter the sleep state, that is, that the activation (wakeup) conditions of all communication nodes A, B, and C are not satisfied. As a result, the collector voltage of the transistor 31 rises, the voltage of the wake-up dedicated line 51 rises, and all the communication nodes A,
B and C go to sleep.

[0022]

Since the present invention is constructed as described above, it has the following effects. It is provided with a starting means for starting each communication node, a signal forming means for forming an on / off signal for starting each starting means, and a transmission path for transmitting the on / off signal to each starting means. Since the activation can be performed by the ON / OFF signal, the configurations of the activation unit and the signal forming unit are simplified, the circuit configuration of each communication node can be simplified, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a multiplex transmission device of the present invention.

FIG. 2 is a time chart showing the operation of the multiplex transmission device of the present invention.

FIG. 3 is a block diagram showing a specific example of an activation system to which the present invention is applied.

FIG. 4 is a block diagram showing another embodiment of the multiplex transmission device of the present invention.

FIG. 5 is a flowchart showing the operation of the present invention.

[Explanation of symbols]

 A, B, C Communication node 1 Microcomputer 2 Multiplex module 3 Wakeup circuit 4 Multiplex transmission line (twisted pair line) 5,51 Wakeup dedicated line 6 Wakeup switch 31 Wakeup transistor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuhiko Kurata No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Nardeck Co., Ltd. (72) Inventor Hitoshi Nakajima No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Nardetsk Within the corporation

Claims (1)

[Claims] 1. A multiplex transmission device for transmitting and receiving between a plurality of communication nodes via a multiplex transmission path, which is provided in each communication node, and which activates each communication node and activates each activation means. A multiplex transmission device comprising a signal forming means for forming an on / off signal and a transmission path for transmitting the on / off signal to each starting means.