JPH03289233A - State monitor method for data transmission system - Google Patents

Abstract

PURPOSE:To monitor autonomous spread monitor state and to inform a fault in real time by allowing a transmission controller detecting the fault to publicate a state monitor frame independently of a prescribed period publicated by each transmission controller and allowing all transmission controllers to receive the state monitor frame. CONSTITUTION:Transmission controllers 3-5 publicate a state monitor frame for each prescribed period and the transmission controllers 2-5 detecting a fault publicate a state monitor frame independently of a prescribed period and the frame is received in real time by transmission controllers other than those publicating the state monitor frame. The transmission controllers 2-5 uses state monitor information 12 in the state monitor frame to be received to monitor the state of the transmission controllers 2-5. Thus, any transmission controller monitors the state of other transmission controllers in the state of autonomous spread.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for monitoring the status of a data transmission system that transmits data between a plurality of transmission control devices connected by a transmission cable.

[Conventional technology]

FIG. 5 is a system configuration diagram showing a conventional state monitoring method of a data transmission system disclosed in, for example, Japanese Unexamined Patent Publication No. 63-240147. In the figure, 31 is a center device;
32, 33, and 34 are terminal devices; each terminal device 32,
33 and 34 communicate only with the center device 31. 30 is a transmission cable that physically connects the center device 31 and the terminal devices 32, 33, and 34.

FIG. 6 shows the center device 31 and each terminal device 32, 33.
FIG.

Next, the operation will be explained. Since the center device 31 monitors the status of each terminal device 32, 33, 34, it monitors the status of each terminal bag [32, 33, 34] by polling. That is, the center device w31 sends a status monitoring request frame R1 to the terminal device 32. Terminal bag that received status monitoring request frame R8! ! 32 sends a status monitoring response frame D□ by the center device 31, and the center device 31 thereby monitors the status of the terminal bag 32.

Thereafter, in the same manner, the center device 31 sends status monitoring request frames R,,R, to the terminal device 33 and the terminal bag [34, and further sends status monitoring response frames D from each terminal device i33, 34. , D, the status of each terminal device 33, 34 connected to the network is monitored.

Furthermore, when an abnormality is detected in the terminal device 33, the terminal device 33 is able to autonomously send a condition monitoring response frame D4 to the center device 31 without the condition monitoring request frame. Status monitoring information is sent to the center device 31.

[Problem to be solved by the invention]

Since the conventional state monitoring method of a data transmission system is realized as described above, a master transmission control device as the center device 31 is required, and the terminal devices 32 to 34 are
If the status monitoring information is not transmitted to each slave transmission control device, or if the center device 31 is abnormal, there is a problem that the status of the system cannot be monitored.

This invention was made to solve the above-mentioned problems, and provides a data transmission system in which any transmission control device can monitor the status of other transmission control devices in an autonomously decentralized state. The purpose is to obtain a method for monitoring conditions.

[Means to solve the problem]

A method for monitoring the status of a data transmission system according to the present invention includes:
Each transmission control device sends a status monitoring frame containing status monitoring information and counter values to all other transmission control devices at regular intervals, and when any of them detects an abnormality, The status monitoring frame is immediately sent to all other transmission control devices regardless of their relationship.

[Effect]

Since the status monitoring information in this invention is autonomously transmitted from each transmission control device to all other transmission control devices at regular intervals, autonomously decentralized status monitoring is possible, and status monitoring frames can be issued. An abnormal transmission control device can be detected by detecting that the hourly counter value is not incremented.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1 is a loop-shaped transmission cable, 2, 3, 4
．． 5 are transmission control devices.

Also, Figure 2 shows each transmission control bag! 2 shows the flow of status monitoring frames between 2, 3, and 4.5.

FIG. 3 is a diagram showing the frame format of the condition monitoring frame, in which 11 is a start flag indicating the beginning of the frame, 12 is condition monitoring information, and 13 is a cyclic (1, 2
,...FFFF, 0, 1, 2...), and 14 is an end flag indicating the end of the frame.

FIG. 4 shows a status monitoring table stored in each transmission control bag @2.3, 4.5, and this status monitoring table is stored in each transmission control device 2, 3 according to the received status monitoring frame.
, 4.5.

Next, the operation will be explained.

As shown in FIG. 1, each transmission control device [2, 3, 4, 5] is connected in a loop by a transmission cable 1, and data information frames and status monitoring frames are transmitted in one direction. That is, transmission is performed in the direction of transmission control bag M2→transmission control device 3→transmission control device 4→transmission control device 5→transmission control device W2. Further, transmission control on the transmission cable 1 uses token passing to avoid collisions on the transmission cable 1.

FIG. 2 shows the flow of status monitoring frames between each transmission control device 2, 3, 4.5. According to this, the transmission control device 2 Then, a status monitoring frame as shown in FIG. 3 is issued. This status monitoring frame is sent to the transmission control device 3. Transmission control bag W4. The data is transmitted to the transmission control device W5 and then to the transmission control device 2 in this order, and taken in by each transmission control device. Further, this status monitoring frame is erased by the transmission control device 2 which is the issuer thereof.

Thereafter, each transmission control device 3, 4.5 issues a status monitoring frame as shown in FIG. 3 at regular intervals in the same manner, and each transmission control device other than the transmission control device that issued this status monitoring frame It is taken in at 2.3°4.5. In this case, since the above-mentioned status monitoring frame is issued independently at fixed intervals by the timer in each transmission control device 2, 3, 4.5, the time between each transmission control bag @2, 3, 4.5 is There is no relationship. In addition, the transmission control device 2 that detected the abnormality
, 3, 4.5 each issue a status monitoring frame regardless of the fixed period as described above, and are received in real time by a transmission control apparatus other than the transmission control apparatus that issued the status monitoring frame. Each transmission control device 2, 3, 4.5 can monitor the status of each transmission control bag f12, 3, 4, 5 based on the status monitoring information 12 in the received status monitoring frame. Furthermore, each transmission control device 2, 3, 4.5 inserts a counter value of 13 when issuing a status monitoring frame. The counter used here is a cyclic counter, and the counter value is incremented each time a status monitoring frame is issued. Each transmission device 2, 3 that received the state start frame
, 4.5 accumulates the status monitoring information 12 and counter value 13 from each transmission control device 2, 3, 4.5 as a table as shown in FIG. 4 for each transmission control device. Then, each transmission control bag j [2, 3, 4, 5] detects that the counter value of the status monitoring table is not incremented even after a certain period of time, and then transmits the transmission control device 2, 3, 4 corresponding to the status monitoring table. It is possible to detect that one of .5 has some kind of abnormality and is no longer able to send out the status monitoring frame.

The method of detecting a transmission control device that is unable to send a status monitoring frame using the counter value 13 as described above can also be done by having each transmission control device 2, 3, 4.5 monitor the reception interval of status monitoring frames. but.

By using the table containing the counter value 13, other software monitors the table to monitor the status of each transmission control device 2, 3, 4.5, and detect a transmission control device that is unable to send a status monitoring frame. is possible.

Note that although the above embodiment shows a case where token passive transmission control is performed in a loop system configuration, it can be similarly applied to any other system configuration or transmission control method, and the same effects as in the above embodiment can be obtained. play.

〔Effect of the invention〕

As described above, according to the present invention, each transmission control device issues a status monitoring frame at regular intervals, and all transmission control devices receive the status monitoring frame, while the transmission control device that has detected an abnormality Since the status monitoring frame is issued regardless of the above-mentioned fixed period and all transmission control devices can receive the status monitoring frame, autonomous decentralized status monitoring is possible and abnormalities can be notified in real time. There is an effect that you can get what you can.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a state monitoring method of a data transmission system according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the flow of a state monitoring frame of this invention, and FIG. 3 is a state monitoring frame of this invention. Frame format diagram showing 4th
5 is a status monitoring table diagram showing the status monitoring contents stored in the transmission control device of the present invention, FIG. 5 is a system configuration diagram showing a conventional status monitoring method of a data transmission system, and FIG.
The figure is an explanatory diagram showing the flow of a conventional status monitoring frame. 1 is a transmission cable, 2, 3, 4.5 is a transmission control device, 1
2 is status monitoring information, and 13 is a counter value. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. 1st Figure 1: Transmission Turf 2.3, 4, 5: 1st IF/1st Figure Status Monitoring Table Figure 1? Country 0 2 3 4

Claims (1)

[Claims] Each of the multiple transmission control devices interconnected via transmission cables sends out a status monitoring frame containing status monitoring information and a counter value at regular intervals, and transmits the status monitoring frame to all other transmission control devices. When any of the transmission control devices detects an abnormality, it sends out a status monitoring frame regardless of the fixed period, and all other transmission control devices receive the status monitoring frame. A method for monitoring the status of a transmission system.