JPH05122200A - Transmission control system - Google Patents

Abstract

PURPOSE:To prevent two or more transfer control systems which operate as an operation system or a standby system from simultaneously operating as the operation systems. CONSTITUTION:This system is provided with transfer control devices 412 and 411 which operate as the operation system or the standby system and transmission lines 421 and 422 performing inquiry between devices. In steps 111 and 113, the inquiry of normality is performed from the standby system to the operation system out of the transfer control devices 412 and 411 using these transmission lines 421 and 422. In the case of no response for the inquiry using the transmission line 421 and 422, the current standby system is switched to the operation system.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a transmission control system, and in particular, it has two transmission control devices for transmission, one of the two is used as an operating system and the other is used as a standby system, and an abnormality occurs in the operating system. The present invention relates to a transmission control system capable of automatically switching to a standby system when the operation is performed.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 4, a transmission control system of this type has a working transmission controller 511, a standby transmission controller 512, a working transmission controller 511 and a standby transmission controller. The communication means 52 for exchanging information with 512 is included. The operation of this system will be described with reference to FIG.

First, as shown in FIG. 5, the standby transmission controller 512 makes an inquiry to the active transmission controller 511 using the communication means 52 (step 61).
It is confirmed whether or not there is a response from the active transmission control device 511 to the inquiry (step 62). If there is a response (Y in step 62), the standby system transmission controller 512 determines that the working system transmission controller 511 is normal, returns to step 61, and repeats steps 61 and 62.

On the contrary, if there is no response (N in step 62), the standby system transmission control device 512 determines that the working system transmission control device 51
It is determined that 1 has become abnormal, and the transmission control device 512, which has been operating as a standby system until now, starts operating as an active system (step 63).

However, in this conventional system, when there is no response from the active transmission controller to the inquiry from the standby transmission controller to the active transmission controller, the active transmission controller becomes abnormal. It cannot be determined whether the communication means between the operating system and the standby control device has become abnormal. Therefore, even if the operating system transmission control device is normal and the communication means is abnormal and there is no response, it is determined that the operating system transmission control device itself has become abnormal, and the standby system transmission control device Will start operating as an active system. Therefore, there has been a drawback that both transmission control devices are operating as an active system.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks, and an object of the present invention is to provide a transmission control system in which two or more transmission control devices do not simultaneously operate as an operating system. Is.

[0007]

The transmission control system according to the present invention comprises first and second transmission control devices operating as an active system or a standby system, and first and second transmission lines for making an inquiry between these devices. And means for inquiring from the standby system device of the transmission control device to the operating system device using the first or second transmission path whether or not the device is in a normal state. When there is no response to the inquiry using the second transmission line, the standby system device is controlled to be switched to the active system device.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a flow chart showing the configuration and operation of an embodiment of a transmission control system according to the present invention. In FIG. 1C, the system of this example includes a 0-system transmission control device 411 and a 1-system transmission control device 412, and a 0-system communication means 421 between them is wired or wireless.
And the 1-system communication means 422. After that, the current transmission control device 411 is
It is assumed that the transmission control device 412 operates as a standby system.

FIG. 3 is a state transition diagram of each transmission control device. In the figure, the standby state 34 is a state in which it operates as a standby system. Both the operating state 32 and the operating state 33 are operating as active systems, but the operating state 32
And the other transmission control device is operating as a standby system (standby state 34), and the operating state 33 is a state when the other transmission control device is not operating (abnormal state 35).

The abnormal state 35 is a state in which a failure or the like of the device has occurred, and the device cannot perform a normal transmission control operation. That is, in each state, when an abnormality such as a device failure occurs, the state transits to the abnormal state 35.

When the abnormal state 35 is recovered, after passing through the initial state 31, the standby state 43, the operating state 32 or 3
It will transition to 3. In this case, the initial state 31
In step 311 of 1., the device is in a state of inquiring whether it is in the normal state or waiting for a switching request from the operating state to the standby state. Then, if there is an inquiry from the other device as to whether or not it is in a normal state, a response to the inquiry is returned, and the device itself becomes the active system and transitions to the operational state 32 (A).

On the other hand, when a switching request is input from the other device, a response to the request is sent back, and the device itself becomes the standby system and transits to the standby state 34 (B). In this case, the inquiry about whether or not the operating system is in the normal state is started.

If there is neither an inquiry nor a switch request, after a predetermined time (timeout), the own device becomes the active system and transitions to the operational state 33 (C). In this case, the switching request is sent to the other device.

When in the operating state 32, in step 321, the own device waits for an inquiry as to whether it is in a normal state or for a request for switching from the operating state to the standby state. Then, if there is an inquiry from the other device as to whether it is in a normal state,
A response to it is returned, and the state of step 321 is entered again (D).

On the other hand, when a switching request is input from the other device, a response to the request is sent back, and the device itself becomes the standby system and transits to the standby state 34 (E). In this case, the inquiry about whether or not the operating system is in the normal state is started.

If there is neither an inquiry nor a switching request, after a predetermined time (timeout), the operation state 33 is entered (F). In this case, the switching request is sent to the other device.

In the operation state 33, in step 331, the switching response waiting state by the communication means 421 of the 0 system is set. After a predetermined time (timeout), a switching request is sent out, and in step 332, the 1-system communication means 422
(G) is set in the waiting state for the switching response. After a predetermined time (time-out), the switching request is transmitted, and in step 331, the switching response waiting state by the communication means 421 of system 0 is again set (H). Until there is a response to the switching request,
Steps 331 and 332 are repeated.

In step 331 or 332, if there is a response, the own device transits to the operation state 32 described above.

In the case of the standby state 34, in step 341, the system waits for a response to the normal state by the communication means 421 of the 0 system. Then, if there is a response from the other device, an inquiry is again made as to whether or not it is in a normal state, and step 341
(I).

On the other hand, if there is no response, after a predetermined time (timeout), an inquiry is made as to whether or not the state is normal, and step 34
In 2, the system waits for a response to the normal state by the communication means 422 of system 1 (J). Then, if there is a response from the other device, an inquiry is again made as to whether or not it is in a normal state, and the state of step 341 is entered (K). If there is no response, after a predetermined time (timeout), the own device becomes the active system and transits to the operational state 33 (L).

Next, with reference to FIGS. 1A and 1B and FIG. 2, the processing in each of the standby state 34 and the operating states 32 and 33 will be described.

FIG. 1A is a flow chart showing the processing in the preliminary state 34 of FIG.

At present, the transmission controller 412 is in the standby state 34 and the transmission controller 411 is in the operating state 32. First,
The transmission control device 412 communicates with the transmission control device 411.
Inquires about the normal state using 421 (step 111
).

If there is a response from the transmission control device 411 to the inquiry in step 111 (Y in step 112),
The device judges that the device is normal and returns to step 111.
Conversely, in response to the inquiry in step 111, the transmission control device 411
If there is no response from the device (N in step 112), the transmission controller 411 is again inquired of the normal state using the communication means 422 (step 113).

If there is a response from the transmission controller 411 to the inquiry in step 113 (Y in step 114),
The device judges that the device is normal and returns to step 111.
Conversely, in response to the inquiry in step 113, the transmission controller 411
If there is no response from (NO at step 114), it is judged that the transmission control device 411 is in the abnormal state 35 and the operation state 33 is entered (step 115).

FIG. 1B is a flow chart showing the processing in the operating state 33 of FIG.

At present, the transmission controller 412 is in the operating state 33 and the transmission controller 411 is in the abnormal state 35. First,
The transmission control device 412 uses the communication means 421.
A request is output to 411 to switch from the active system to the standby system (step 121).

If there is a response from the transmission control device 411 to the request in step 121 (Y in step 122), it is determined that the transmission control device 411 has started as the standby state 34 and the operation state 32 is entered (step 32). 125). On the contrary, if there is no response from the transmission control device 411 to the request in step 121 (N in step 122), the transmission control device 412 uses the communication means 422 to switch the transmission control device 411 from the active system to the standby system. The request is output again to replace it (step 12).
3).

If there is a response from the transmission control device 412 to the request in step 123 (Y in step 124), it is judged that the transmission control device 411 has started as the standby state 34, and the operation state 32 is entered (step 32). 125). On the contrary, if there is no response from the transmission control device 411 to the request in step 123 (N in step 124), the transmission control device 411 judges that it is in the abnormal state 35 and returns to step 121.

FIG. 2 is a flow chart showing the processing of the operational state 32. The transmission controller 412 is currently in the operational state 32 and the transmission controller 411 is in the standby state 34.

The transmission control device 412 waits for a normal state inquiry or a request for switching from the active system to the standby system from the transmission control device 411 (step 21).

If there is no inquiry or request in step 21 (N in step 22), it is judged that the transmission control device 411 has entered the abnormal state 35 and the operation state 33 is entered (step 23).

If there is a status inquiry in step 21 (Y in step 22, and status inquiry in step 24), a response is returned to the transmission control device 41 (step 25), and step 21
Return to. If there is a switching request in step 21 (step 2
2, Y, switching request in step 24), transmission control device 411
Transmission control device 412
Becomes a standby system (step 26), returns a response to the switching request (step 27), and shifts to the standby state 34 (step 2).
8).

That is, according to the present embodiment, since two transmission paths are provided and the request by the other side is sent again even if there is no response from one side, whether the transmission control device itself becomes abnormal or not, communication is performed. It is possible to determine whether the means has become abnormal. Furthermore, when there is no response to the inquiry using both of these systems, it is judged that the device itself is in an abnormal state and that the device will not start operating again as an active system, and the standby system device is operated. Since the control is performed so as to switch to the system, two or more transmission control devices do not simultaneously operate as the operating system.

Further, in this embodiment, a switching request is output from the newly operating system device to the original operating system device, and when there is a response to this, the original operating system device is returned to the standby system. Therefore, even if a device once in an abnormal state is restored, two or more transmission control devices do not simultaneously operate as active systems.

It is obvious that the present invention can be applied to the case where more transmission control devices are provided, and more multi-line transmission paths may be provided.

[0038]

As described above, according to the present invention, a plurality of transmission lines are provided, and even if there is no response from one side, the request from the other side is sent out again. Therefore, when there is no response to an inquiry using both systems. By determining that the device itself is in an abnormal state and controlling the device of the standby system to switch to the active system, it is possible to avoid the state in which two or more transmission operational devices simultaneously operate as the active system. There is an effect.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a transmission control system according to an embodiment of the present invention and its standby state and operating state 32.
3 is a flowchart showing the processing in FIG.

FIG. 2 is a flowchart showing processing in an operating state 33 in the system of FIG.

FIG. 3 is a state transition diagram showing each operation of the system of FIG.

FIG. 4 is a block diagram showing a configuration of a conventional transmission control system.

5 is a flowchart showing a process of the system of FIG.

[Explanation of symbols]

 411, 412 Transmission control device 421, 422 Communication means

Claims (1)

[Claims] 1. A first and second transmission control device operating as an active system or a standby system, first and second transmission paths for making an inquiry between these devices, and the first or second transmission control device.
Inquiring using the first and second transmission lines, including means for inquiring from the standby system device among the transmission control devices to the operating system device using the transmission line The transmission control system is characterized in that the standby system device is controlled so as to be switched to the active system device when there is no response.