JP2703989B2 - Station connection order confirmation method for loop communication systems - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a station connection confirmation system of a loop communication system for confirming a station connection order using a certain area on a frame.

(Conventional technology) Conventionally, a control station issues a loopback instruction to a specific station, transmits a frame while changing one station after another, and waits for a response frame. Depending on whether or not the response frame has been received, the stations before and after the specific station are checked to confirm the connection order of the stations.

However, in such a conventional method, there is a problem that the stability of the transmission path is poor due to loopback, and that it is not possible to confirm if a plurality of transmission paths are not normal.

(Problem to be Solved by the Invention) The conventional station connection confirmation method has a drawback that the loopback is performed and the stability of the transmission path is poor.

There is also a problem that confirmation cannot be performed unless a plurality of transmission paths are normal.

The present invention solves the above-described problems, and can maintain the stability of a transmission path, and can confirm the connection order of stations if communication is possible even when a plurality of failures occur in the transmission path. It is an object of the present invention to provide a station connection confirmation method for a mobile communication system.

[Means for Solving the Problems] According to the present invention for solving the above problems, a control station and a plurality of transmission stations are connected in a loop by a transmission path, and a frame is circulated on the transmission path. In a loop communication system for performing communication between stations including the control station and the transmission station, the frame is at least a detection area for recording the number of each station, and information for recording each transmission station. A first reading unit for reading a value including a number recorded by the upstream station of the own station, which is recorded in the detection area on the frame, First writing means for writing a value including the number of the number in the detection area on the frame, detection means for detecting a request for information collection from the control station, and when the detection means detects a request for information collection, Said The number recorded by the upstream station of the own station read by the first reading means and the number of the own station are recorded in a predetermined area allocated to the own station in the control area on the frame and notified to the control station. Notifying means, the control station reads a value recorded in the detection area on a frame, and the control station reads the value including the number of the own station in the detection area on the frame. Second writing means for writing information to the transmission station, information collection request means for requesting each transmission station to collect information using the control area on the frame, and each of the information recorded in the control area on the frame. And a confirmation unit for confirming the connection order of the connected stations using the number notified from the transmission station and the value read by the second reading unit.

(Operation) According to the present invention, the control station and other transmission stations are provided with a reading function and a writing function for a specific area on a frame. These functions are a function of reading the value set by the station on the upstream side with respect to the flow of the frame from the receiving station, and a function of rewriting the value of the specific area to the downstream.

First, the control station requests information from each station using the control area on the frame. Each station sets its own number, and upon receiving a request from the control station, reads the value on the frame using the above function. Then, the value and the number of the own station are notified to the control station using the control area.

When the control station receives the information notified from each station, the values read by that station based on the numbers set by each station are arranged in a table, and the connection order of the stations is determined. You can confirm the order.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a configuration diagram of a frame. As shown in FIG. 1, the frame includes a frame header 12, a detection area 1, a control area 2, and a data area 13. FIG. 2 is a configuration diagram of a loop communication system according to one embodiment of the present invention.

3 is a control station, 4 to 6 are stations, 8 to 11 are registers, and 14 is a transmission line. The control station 3, the station (2) 4, the station (3) 5, and the station (4) 6 are connected by a transmission line 14.

Each station sets its own number on the right side of the lasters 8 to 11 at the same time when it starts up. These registers 8 to 11
The value on the frame is read on the read side, and the value on the frame is rewritten to the value set on the write side and transmitted to the write side downstream.

Therefore, when all the stations start up, for example, the control station 3
In the register 8, the value on the read side is the upstream station (4) 6
"4" set by is detected.

To check the connection order of the stations using this function,
The control station 3 requests each station to collect information using the control area 2 on the frame. As is clear from the frame structure in FIG. 1, the control area 2 is a collection of small areas for each station. That is, it is finely divided into small areas (slots) allocated to each station, and when the control station 3 requests each station to collect information, an information collection request command is set all together in the divided slots. It is done by doing.

The control station 3 sets the information notified from each station in the control station table 7 shown in FIG. 3 based on the number set by each station. Further, the control station 3 sets the value “4” on the read side of the register 8 in the control station table 7. As a confirmation method, the data is confirmed starting from data where the station number in the control station table 7 is the same as the own station number.

As described above, in the present embodiment, by providing a simple function, detection can be performed without performing loopback, the stability of the transmission path is improved, and the order can be confirmed with one transmission path.

[Effects of the Invention] As described above, according to the station connection confirmation method of the loop communication system of the present invention, by adding a simple function to the station, the connection order of the stations can be confirmed without performing loopback. Therefore, the stability of the transmission path is improved. In addition, since the connection order of the stations can be confirmed by one transmission line system, it is possible to confirm even when another transmission line has a failure. Also, when the control station confirms the station connection order, the information collection request is made to all the stations all at once using the control area of the frame.
Information for confirming the station connection order can be collected.

[Brief description of the drawings]

FIG. 1 is a block diagram of a frame, FIG. 2 is a block diagram of a loop communication system according to an embodiment of the present invention, and FIG. 3 is a diagram showing the contents of a control station table. 1 ... Detection area, 2 ... Control area, 3 ... Control station, 4,5,6 ...
Stations, 7 ... control station table, 8, 9, 10, 11 ... registers, 12 ...
Frame header, 13 ... data area, 14 ... transmission path.

Claims (1)

(57) [Claims] 1. A loop communication system in which a control station and a plurality of transmission stations are connected in a loop by a transmission path, and a frame is circulated on the transmission path to perform communication between stations including the control station and the transmission station. In the above, the frame comprises at least a detection area for recording the number of each station, and a control area for recording information for each transmission station, wherein the transmission station First reading means for reading a value including the number recorded by the upstream station of the own station, which is recorded in the detection area; and first reading means for writing the value including the number of the own station to the detection area on the frame. Writing means; detecting means for detecting a request for information collection from the control station; detecting a request for information collection by the detecting means, the number recorded by the upstream station of the own station read by the first reading means. And a notifying unit that records the number of the own station in a predetermined area allocated to the own station in the control area on the frame and notifies the control station of the number. Second reading means for reading a value recorded in the detection area; second writing means for writing a value including the number of the own station in the detection area on a frame; and a control area on the frame. Information collection requesting means for requesting each of the transmission stations to collect information by using, a number notified from each of the transmission stations recorded in a control area on the frame, and the second reading means. Checking means for checking the connection order of the connected stations using the read values. A station connection checking method for a loop communication system.