JPS5961331A - Method for processing failure of transmission system - Google Patents

Abstract

PURPOSE:To stop the operation of a device to be controlled, by storing whether or not there is a transmission error in a received signal when it is discriminated there is the transmission error based on the content of storage. CONSTITUTION:Sequencers A, B, C transmit data stored in a storage area 6 from output interfaces 2a, 2b, 2c and a check code such as parity to detect the transmission error. The sequencers A, B, C check the data based on a check code received by input interfaces 1a, 1b, 1c. When a parity error is detected in the signal received via the input interface of the sequencer B for example, a flag P2 corresponding to the sequencer B is set to logical 1. When the flag P2 is set to logical 1, a sequence instruction JMPO is executed, the step jumps unconditionally to the sequence instruction JMPO and the operation of the device to be controlled is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling equipment to be controlled when an error occurs in a transmitted signal.

Conventionally, in transmission systems that include sequencers that transmit and receive signals using optical fibers, when a transmission error occurs in the signal being transmitted, it is difficult for the operator to notify the operator of the occurrence of such a transmission error. No consideration was given to informing them. Moreover, even if the operator is notified of the occurrence of a transmission error, no consideration is given to allowing the operator to take any countermeasures.

An object of the present invention is to provide a signal processing method for a transmission system that improves the maintainability of equipment and prevents malfunctions when a signal transmission error occurs in the transmission system.

FIG. 1 is an overall system diagram of an embodiment of the present invention.

Multiple sequencers A, B, C, input interface 1
a*1 b! 1c and an optical fiber la via output interfaces 2a, 2b, 2c.

It is connected in a loop by lb and ec. Data is transmitted and received between sequencers A, B, and C via optical fibers la, 1b, and lc, and the equipment to be controlled is controlled.

FIG. 2 shows a data memory map stored in sequencer B. Sequencer B includes read-only memory, random access memory, central processing unit, and the like.

Store area 3 in the read-only memory stores a sequencer program common to sequencers A, B, and CK for sequencer B to operate as a sequencer.

In the storage area 4 of the random access memory, a so-called user program is stored that causes a specific device to be controlled to perform a desired operation. In the store area 5, a flag indicating whether or not there is a transmission error is stored as described later. Another storage area 6 of the random access memory has an optical fiber t? a, eh
,l! Data being sent and received via c is stored. The remaining sequencers A and C still have the same configuration as sequencer B.

Each sequencer A, B, C1''l: transmits the data stored in the storage area 6 and a check code such as verity for detecting transmission errors from the input/output interfaces 2a, 2b, 2c.Sequencer A
, B, C are also input interfaces la, lb, l
The data is checked based on the check code received at c.

FIG. 3 is a diagram showing the store state of the store area 5.

Flags P1 to Pn ld n sequencers A.

It corresponds to B and C individually. Sequencer A.

When there is no transmission error in the signals input and received by B and C through the input interfaces la, lb, and lc, logic "0" is stored, and when there is a transmission error, logic 1- is stored.
1" is stored.

For example, as a result of a parity check on a signal received through input interface 1b of sequencer B,
When there is a transmission error, the flag P2 corresponding to sequencer B becomes logic "1". Remaining sequencers A and C
When the received signal has no transmission j1%, P2
Flag PI other than.

P3. ..., Pn is logic "0". Such a parity check is performed by executing a program stored in the storage area 3 or 4.

A specific example of the user program stored in the store area 4 in sequencer B is shown in FIG. When the flag P2 is logic "0", the user program 7 for operating the equipment to be controlled is executed.

When sequencer B detects a transmission error in the received signal as described above, flag P2 becomes logic "1". Therefore, sequence instruction JMPO is executed. Therefore, this sequence command JM P OK causes the sequence command JM E O to unconditionally jump 1-1 and stop the operation of the equipment to be controlled. As another example, when the flag P2 is logic "1", the equipment to be controlled may be controlled to perform only safe operations. When there is a transmission error in the received signal in this way.

In the embodiment shown in FIG. 4, each step of the user program 7 that requires the equipment to be controlled to operate normally is not executed, thus improving maintainability.

As described above, according to the present invention, whether or not there is a transmission error in the received No. 18 is stored in the memory, and based on the stored contents, when there is a transmission error υ, the device to be controlled operates. Maintainability is improved by halting the operation or allowing only safe operations to take place.

[Brief explanation of the drawing]

FIG. 1 & Overall system diagram of an embodiment of the l-tree invention, No. 21
1 shows the data memory map of the sequencer B. FIG. 3 shows the store state of the store area 5, and FIG. 4 shows the program executed in the sequencer B. A, B, C-...Sequencer, e a, l! b,
e c-optical fiber, la, 1. b, lc...Input interface, 2a, 2b, 2c...Output interface, 3.4, 5.6...Store area agent Patent attorney Kei Nishi Department Figure 1 Figure 2 Figure 3 Figure 4 161-

Claims (1)

[Claims] Checks whether the received signal is correct, stores the result in memory, and uses the stored contents to ensure that the equipment to be controlled operates safely when there is a transmission error in the received signal. A transmission system failure handling method characterized by causing the transmission system to stop operating.