JPH01215152A - Abnormality informing system in loop transmission line - Google Patents

Abstract

PURPOSE:To prevent the reduction in the effective data transfer rate by sending end flags consecutively from a data processing module having received end flags consecutively to the data processing module just one step below. CONSTITUTION:When (n) consecutive end flags are inputted to a data processing module 100 from a transmission line 302, it is detected by an end flag consecution detection circuit 105 and informed to a data processing section 106. The data processing section 106 discriminates is as the occurrence of a fault anywhere the transmission line to give an instruction to the data transmission control section 107 to send (n) consecutive end flags. The data transmission control section 107 sets a selector 109 to the position of the end flag consecution generator 108 and returns it to its own output after the (n) end flags are sent. The output of the selector 109 is outputted to a transmission line 301 through a transmitter 104. Thus, the abnormal state is informed by using the end flag without defining an abnormal signal and the reduction in the effective data transfer rate is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a data processing device having a loop transmission path,
In particular, the present invention relates to an abnormality notification method for notifying all data processing modules connected to a loop transmission path of an abnormality in a loop transmission path.

(Prior Art) Conventionally, this type of data transmission equipment has often adopted a method based on the HDLC procedure, and has detected an abnormality by using continuous transmission of 16 or more bits of logic 11', which is an abort pattern according to the HDLC procedure. 7'l:,.

However, if there is no logical Ig1%0pt-inserted after five consecutive logical%1# pits according to the %HDLC procedure, M)'II 11# or 10
A method of generating a stack of # and notifying the module of all data processing in the loop transmission path, or a method of generating a specially set abnormal pattern and similarly notifying the module are adopted. ) The data processing device f having the conventional loop transmission path described above
In the case of the former method mentioned above, since stuff 22 is logically generated, all the data of the largest frame is 11#.
Alternatively, considering the case of %ON, it is necessary to generate a stack longer than the maximum frame length, which has the disadvantage of a large detection delay.

On the other hand, since the latter method has a unique pit pattern, it has the disadvantage that the effective data transfer rate drops in systems with high-speed serial transmission lines such as loop transmission lines.

The purpose of the present invention is to continuously send the trailing flag from the data processing module that detected the input disconnection to the immediately lower data processing module to notify the transmission path failure, and to repeat the same procedure so that the trailing flag is continuously transmitted to the immediately subordinate data processing module. Loop transmission is configured such that the above drawback is eliminated by continuously sending the tail flag to the data processing module immediately below the input data processing module, and the effective data transfer rate does not decrease. The object of the present invention is to provide a road abnormality notification method.

(Means for Solving the Problems) In the loop transmission line abnormality notification system according to the present invention, at least two data processing modules are connected by a unidirectional loop transmission line, and data are transmitted and received unevenly between each other using asynchronous variable length frames. However, each variable-length frame has a unique pit pattern that is different from the first flag and the last flag. , a loop transmission path abnormality notification method for a data processing device in which the time fill of the loop transmission path other than the variable length frame is defined as the repetition of a fixed bit pattern other than the leading flag and the trailing flag, Each data processing module is comprised of a trailing flag continuity generator, a trailing flag continuity detection circuit, an input disconnection detection circuit, and data control/processing means.

The trailing flag continuous generator is for continuously sending n trailing flags to the loop transmission line.

The tail flag consecutive detection circuit is for detecting that n consecutive tail flags are input from the loop transmission line.

The input disconnection detection circuit is for detecting that the input signal from the loop transmission path is disconnected.

The data system a/processing means receives data from the loop transmission line.

When the input signal is disconnected, n tail flags are continuously sent to the loop transmission path, and the next lower data processing module is notified of the abnormality in the loop transmission path. Detects continuous mtv tail flag signals, detects that an abnormality has occurred in the loop transmission path, and repeats the procedure of successively sending n tail flags to the next lower data processing module. ,
This is a special feature that notifies all data processing modules placed on the loop transmission path of abnormalities in the loop transmission path.

(Example) Next, the present invention will be explained with reference to the drawings.

Figure @1 is a block diagram showing an embodiment of the loop transmission line abnormality notification system according to the present invention.

In FIG. 1, 10G is a first data processing module, 200 is a second data processing module, 101 is a reception 5.1G2 is a data reception control section, 103 is an input disconnection detection circuit, 104 is a transmitter, 105 10g is a data processing unit, 107 is a data transmission control unit, 108 is a continuous trailing flag generator, 109 is a selector,
301 and 302 are transmission lines, respectively.

In FIG. 1, a first data processing module 100 receives a signal from a transmission line 302, processes a frame, and outputs the signal to a transmission line 301. , @2, the data processing module 200 receives the signal from the transmission line 301, processes the frame, and outputs it to the transmission line 302, forming a loop transmission line as a system.

Since the first data processing module 1007 and the data processing module 200 of @2 have almost the same functions, the first data processing module 100 will be described as a representative.

The transmission line signal input from the transmission line 302 is sent to the receiver 101.
The signal is input to the data receiving OI system section 102, the input disconnection detection circuit 103, and the trailing flag continuity detection circuit 1057. Data reception control section 10
In 2, when the start flag of a frame is detected, it is checked whether the frame is addressed to itself, and if it is addressed to itself, it is rejected.

- captures the program and outputs it to the data processing unit 106.

On the other hand, if it is not addressed to itself, the head flag is output to the data transmission control unit 107.

Furthermore, if data other than the frame head flag is input, it is erased. The data transmission control unit 107 inputs data to be transmitted from the data processing unit 106,
Frame and output.

However, passing data from the data reception control unit 102 is input. However, if data from the data processing unit 106 is being transmitted, the passed data will be deleted. The frame output from the data processing unit 106 passes through the selector 109, is converted into a transmission line signal by the transmitter 104, and is output to the transmission line 301.

Here, the operation when the transmission line 302 is disconnected will be explained.

When the transmission line 302 is disconnected, no transmission line signal is input to the receiver 101, so the input disconnection detection circuit 103 detects input disconnection and notifies the data processing unit 106. The data processing unit 106 determines that the transmission path 302 has become a failure, and sends the data transmission control unit 10 frl! Instructs to send all consecutive tail flags of 1 (n: positive integer>2).

The data transmission control unit 10 controls the selector 109 to select the output of the last flag continuous generation 4108, and n
If all the last flags are sent out, the data transmission control section 10 switches to the output. The transmitter 104 outputs the signal from the selector 109 to the transmission line 301 as is.

Next, a case where n consecutive end flags are input to the data processing module 100 from the transmission path 302 will be described.

When n consecutive trailing flags are input from the transmission path 302, they are detected by the trailing flag consecutive detection circuit 105,
The data processing unit 106 is notified.

The data processing unit 106 determines that a failure has occurred somewhere on the transmission path, and instructs the data transmission control unit 10 to send n consecutive tail flags. In the data transmission control unit 10, the selector 109 is set to the end flag continuous generation 4118 side.

After the last flag of n(I!I is transmitted, it is returned to its own output. The output of selector 109 is
04 and is output to the transmission line 301.

(Effects of the Invention) As explained above, the present invention conveys a trailing flag from a data processing module that detects an input disconnection tfT to the immediately subordinate data processing module, and then sends it out to notify a transmission path failure. However, by repeating the same procedure 11 times, the loop transmission line becomes a failure due to the continuous signal of the last flag being input and the last flag being continuously sent from the running data processing module to the data processing module immediately below it. This has the advantage that not only can all data processing modules in the system be quickly notified of the fact that something has happened, but also that an abnormal state can be instantly notified by defining another abnormal signal using the trailing flag.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a loop transmission path abnormality notification system according to the present invention. 100.200...Data processing module 101...
-Receiver 102...Data reception control unit 103...Input disconnection detection circuit 104...Transmitter 105...Tail flag continuity detection circuit 106...Data processing unit 10F...Data transmission control unit 108...Tail flag continuous generator 109...Selector 301.302...Transmission line

Claims (1)

[Claims] At least two data processing modules are connected by a unidirectional loop transmission path and transmit and receive data to and from each other using asynchronous variable length frames, each of which has a leading flag and a trailing flag having a unique pit pattern. An abnormality in the loop transmission path of a data processing device defined as a portion surrounded by a flag, and in which the time fill of the loop transmission path other than the variable length frame is defined as a repetition of a fixed pit pattern other than the head flag and the end flag. In the notification method, each of the data processing modules includes a trailing flag continuous generator for successively sending n trailing flags (n: a positive integer ≧2) to the loop transmission path; a trailing flag continuity detection circuit for detecting that the n consecutive trailing flags are input from the loop transmission path; and an input disconnection circuit for detecting that the input signal from the loop transmission path is disconnected. When the input signal from the detection circuit and the loop transmission line is disconnected, the n tail flags are successively sent to the loop transmission line, and the data processing module of the lower order is sent to the loop transmission line. Notify of abnormality,
The next lower data processing module detects the continuous signal of the n end flags, detects that an abnormality has occurred in the loop transmission path, and also sends the n last data processing module to the next lower data processing module. data control/processing means for repeating the procedure of successively sending out the last flags and notifying all the data processing modules placed on the loop transmission path of an abnormality in the loop transmission path; A loop transmission line abnormality notification method characterized by: