JPH02272931A - Information transmission system - Google Patents

Abstract

PURPOSE:To simplify system operation by connecting a duplexed station through a duplexing controller, for which specified function is provided, to a communication line. CONSTITUTION:When information are exchanged with a second station 3 for which a first station 1 is duplexed, a duplexing controller 4 is provided to connect the second station 3 to a LAN line 2. For this duplexing controller 4, function is provided to detect the normality of a living machine 3a in the second station 3 and function is provided to transmit information, which are received form the LAN line 2, to both the living machine 3a and an auxiliary machine 3b when the living machine 3a is normal and to transmit the information, which are received from the LAN line 2, only to the auxiliary machine 3b when the living machine 3a is abnormal. Further, function is provided to send only the information from the living machine 3a to the LAN line 2 when the living machine 3a is normal and to send the information from the auxiliary machine 3b to the LAN line 2 when the living machine 3a is abnormal. Thus, the system operation can be simplified.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is directed to local area networks (hereinafter referred to as LA).
This relates to an information transmission system in which a plurality of stations such as N) are connected through communication lines and the stations exchange information with each other.

[Conventional technology]

FIGS. 3 and 4 are block diagrams showing a conventional information transmission system used, for example, in the MacMess 620 manufactured and sold by Mitsubishi Electric Corporation. Figure 3 is a normal LAN
In the figure, 1 is the first station, and 2 is the LAN as a communication line to which this first station 1 is connected.
Line 3 is a second station that is connected to this LAN line 2 and exchanges information with the first station 1. In addition, Figure 4 shows a case where the second station 3 of a normal LAN is duplicated, and in the figure, 3a is the active machine of the duplicated second station 3, and 3b is a standby machine that backs up the current machine 3a. It is a machine.

Next, the operation will be explained. In the information transmission system shown in FIG. 3 in which each station is not duplicated, a unique address is given to each of the first and second stations 1 and 3, and the first station 1 and the second station Information is exchanged with station 3 based on its address via LAN circuit [2. Here, if an abnormality occurs in the second station 3, it becomes impossible to exchange information between the two stations. Therefore, as shown in Fig. 4, the second station 3 has a redundant configuration consisting of a working machine 3a and a standby machine 3b, and reliability is improved by having the standby machine 3b back up when the working machine 3a is abnormal. I'm trying to improve.

In that case, at the second station 3, the standby machine 3
b must always be kept in the same state as the current machine 3a. Therefore, the first station 1 sends the same information not only to the active machine 3a of the second station 3 but also to the standby machine 3b, and when the active machine 3a is normal, the same information is sent from the standby machine 3b. Control is performed such that only the information sent from the working machine 3a is received while discarding the information sent from the working machine 3a, and when the working machine 3a is abnormal, only the information sent from the standby machine 3b is received. In this case, the standby machine 3b of the second station 3 has a separate address assigned to it, which is different from that of the working machine 3a, even though it is a backup stage for the working machine 3a.

[Problem to be solved by the invention]

Since the conventional information transmission system is configured as described above, when the first station 1 is duplexed and exchanges information with the second station 3, the first station 1 has the second station 3. active machine 3a and standby machine 3
Is it foolish to require extra control to keep the current aN3a of the second station 3 in the same state?
Since it is necessary to give separate addresses to the standby unit 3b and the standby unit 3b, there are problems such as inconvenience in terms of system operation.

This invention was made to solve the above-mentioned problems, and aims to provide an information transmission system that does not require extra control for exchanging information with duplicated stations and is easy to operate. purpose.

[Means to solve the problem]

The information transmission system according to the present invention has a duplex station with a working machine and a backup machine to back it up, and the duplexed station has a function to detect the normality of the working machine, and a function to communicate when the working machine is normal. The receiver transmits pressure information from the line to both the active aircraft and the standby aircraft, and when the active aircraft is abnormal, the information is transmitted only to the standby aircraft, and when the active aircraft is normal, only the information from the active aircraft is sent to the communication line. It is connected to a communication line using a redundant control device that has the function of sending information from the standby unit to the communication line in the event of an abnormality in the active unit.

[Effect]

The duplication control device in this invention determines the normality of the active machine, and when the active machine is normal, transmits information received from the communication line to both the active machine and the standby machine of the duplexed station, and The information from the standby machine is discarded and only the information from the working machine is sent to the communication line.In the event of an abnormality in the working machine, the information received from the communication line is transmitted only to the standby machine, and the information from the standby machine is sent to the communication line. This eliminates the need for extra controls when exchanging information with duplicated stations, and also eliminates the need to provide separate addresses for the active and standby machines of duplicated stage rentals. To realize an information transmission system that is easy to operate by eliminating .

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1 is a first station, 2 is a LAN line as a communication line, 3 is a second station, 3a is a working machine, and 3b is a standby machine. Since this is the same or equivalent part, detailed explanation will be omitted. 4 also connects the second station 3 to L
It is a redundant control device for connecting to AN line 2, and is the second stage! A function to detect the normality of the active machine 3a of I/3, if the active machine 3a is normal, the information received from the LAN line 2 is transmitted to both the active machine 3a and the standby machine 3b, and if the active machine 3a is abnormal. If there is a function, the information received from the LAN line 2 is transmitted only to the standby machine 3b, and if the working machine 3a is normal, only the information from the working machine 3a is sent to the LAN line 2, and if the working machine 3a is abnormal. If so, it has a function of sending information from the standby device 3b to the LAN line 2. Reference numeral 5 designates a LAN line similar to the LAN line 2 for connecting the active machine 3a and standby machine 3b of the second station 3 to this duplex control device f4.

Next, the operation will be explained. The active machine 3a and standby machine 3b of the second station 3, which are connected to the LAN line 2 by the duplex control device 4, are seen as one station from the first stage My1. Therefore, the first station 1 needs the redundant control device 4 to exchange information with the active machine 3a and the standby machine 3b of the second station 3.
There is no need to worry about whether or not the second station 3 is duplexed. The duplication control device 4 handles all control for duplication.

That is, from the first station 1 to the second station 3
The information is received by the redundant control device 4 via the LAN line 2, and sent via the LAN line 5 to both the active machine 3a and the standby machine 3b. Further, the information from the second station 3 to the first station 1 is received by the duplex control device 4 via the LAN line 5, and the information from the backup device 3b is discarded and only the information from the active device 3a is received. It is sent to the first station 1 via the LAN line 2. Further, the duplex control device 4 receives a signal at a constant period from the current device 3a and detects the occurrence of a failure. When the redundancy control device 4 detects a failure in the active machine by not detecting this signal at a certain period, the information from the first station 1 is used to replace the active machine 3a with the backup machine 3b. The information is not sent to the machine 3a, but only to the normal spare machine 3b, and all information from the normal spare machine 3b is transmitted to the first station 1, and the information from the failed working machine 38 is discarded. .

Also, since the first station 1 exchanges information with the duplex control device 4, the first station 1 exchanges information with the duplex control device 4.
If the address of the non-duplicated second station 3 is given as the address of the second station 3, it is no longer necessary to know the addresses of the active machine 3a and standby machine 3b of the second station 3. Therefore, it is possible to have an independent address system for the active machine 3a and the standby machine 3b of the duplexed second station 3, and it is possible to have an independent address system for each station 3, regardless of whether it is duplexed or not. addresses can be numbered.

Here, FIG. 2 is a flowchart showing the operating procedure of this duplex control device 4, and FIG. 2(a) shows the operating procedure when processing information received from the first station 1. That is, when information is received from the first station 1 (step 5TI), it is determined whether the active machine 3a of the second station 3 is normal (step ST
2). Here, the determination of whether the current machine 3a is normal or abnormal is made by referring to a failure flag, and if the failure flag is not set, it is determined to be normal, and if it is set, it is determined to be abnormal. As a result of the determination, if the active machine 3a is normal, the information received from the first station 1 is transmitted to the active machine 3a of the second station 3 (step ST3).
Furthermore, the information is also transmitted to the standby device 3b (step ST4). Further, if the result of the determination is that there is an abnormality, the process skips step ST3 and directly advances to step ST4, and the information from the first stationary unit 1 is transmitted only to the backup device 3b.

Further, FIG. 2 (6) shows the operating procedure of the duplex control device ff4 when processing information to be transmitted to the first stage 4-1. That is, when the information to be transmitted to the first station 1 is received (step ST5), it is determined whether the working machine 3a of the second station 3 is normal (step ST6'). This determination of the normality of the working aircraft 3a is performed in the same manner as step ST2 in FIG. 2(a) K. As a result of the determination, if the current i3a is normal, it is determined whether the 'information sent to the first station 1 is sent from the current device 3a (step ST7),
In step ST8, only the information sent from the active machine 3a is sent to the first station 1 via the LAN line ls2.
)・, the information from the backup device 3b is discarded without doing anything.

Further, as a result of the determination in step ST6, if the active device 3a is abnormal, the received information is from the backup device 3b, so the process proceeds to step ST8 and the information is transferred to the first
The data is sent to station 1.

Furthermore, FIGS. 2(c) and 2(d) show the operating procedure of the duplex control device 4 when detecting the normality of the working machine 3a of the second station 3. That is, the active machine 3a of the second stage control 3 maintains its own normality using the redundant control device 4.
A predetermined signal is sent to the duplex control device 4 at regular intervals in order to notify the duplex control device 4. When duplex control bag #4 receives this signal (step ST9), it sets the count value of the built-in counter to a predetermined value each time (step ST9).

Apart from this, the duplex control bag [4] executes a routine shown in FIG. 2(d) as an interrupt process that occurs at a predetermined period. Therefore, each time this routine is started, the counter is decremented (step 5TII) and its count value decreases. Since the count value of this counter is set to a predetermined value each time a signal arrives from the working machine 3a as described above, it will never become "0" if the working machine 3a is normal.

When the active machine 3a becomes abnormal and the signal is interrupted, the count value of the counter eventually becomes "0". When it is detected that the count value of the counter becomes "0" (step 5T12)
), set a failure flag for the current machine 3a (step 5T1
3) Display that the current machine 3a is out of order. This failure flag is set at step ST in FIGS. 2(a) and (b).
2 and Sr1.

In the above embodiment, the signal transmission form between the redundant control device and the active machine and standby machine of the second station is the same as the signal transmission form between the first stage and the redundant control device. Although the case where the same LAN line is used has been described, it may also be a bus used within the system of the working machine and standby machine of the second station, and the same effect as in the above embodiment can be achieved.

〔Effect of the invention〕

As described above, according to the present invention, there is a function to determine the normality of the working machine of a duplicated station, and when the working machine is normal, information received from the communication line is transmitted to both the working machine and the standby machine, A function that transmits the relevant information only to the standby machine when there is an abnormality in the working machine, and when the working machine is normal, only information from the working machine is sent to the communication line, and when there is an abnormality in the working machine, information from the standby machine is sent to the communication line. Since the configuration is such that the duplexed station is connected to the communication line using the duplex control device IT, which has the function of Another advantage is that there is no need to give separate addresses to the active and standby machines of the duplicated stations, which simplifies the operation of the system.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an information transmission system according to an embodiment of the present invention, FIG. 2 is a flowchart showing its operating procedure, and FIGS. 3 and 4 are block diagrams showing a conventional information transmission system. 1 is the first station, 2 is the communication line (LAN line)
, 3 is a second station, 3a is a working machine, 3b is a standby machine, and 4 is a redundant control device. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] In an information transmission system in which a plurality of stations are connected via communication lines and information is exchanged between the stations, at least one of the stations is duplexed by a working machine and a standby machine that backs up the working machine, and the duplexed station is a detection function that detects the normality of the working machine of the station, and transmits information received from the communication line to both the working machine and the standby machine when the working machine is normal, and transmits the information received from the communication line to both the working machine and the standby machine when the working machine is abnormal. A transmission function that transmits information received from a line only to the standby machine, and when the working machine is normal, only information from the working machine is sent to the communication line, and when the working machine is abnormal, information from the standby machine is transmitted. An information transmission system characterized in that the duplexed stations are connected to the communication line via a duplex control device having a sending function for sending out the information to the communication line.