JPS6231234A - Optical remote input/output device - Google Patents

Abstract

PURPOSE:To diagnose the abnormal contents and abnormal points promptly by providing an RAS data in a part of the transmission data outputted from a process controller to each terminal and not updating the RAS data only in the case of abnormality. CONSTITUTION:As shown in a signal A, an abnormal signal '1' is set beforehand in a part of the RAS data and transmitted from a serial transmission equipment 12. Since optical remote input/output devices 20a-20b are normal, the transmission data B and C are rewritten from '1' to '0' with respect to the RAS data of a self data slot. But if there is disconnection at a point M, the optical remote input/output device 20c diagnoses it as an abnormal reception. This device does not rewrite a circuit abnormal signal, but rewrites an MPU abnormal signal '1' to an MPU normal signal '0', and transmits it to the next stage. Therefore, in the received data into a serial transmission equipment 13, as shown in a signal E, only the 3rd RAS data is not '0', whereby the circuit between the devices 20b and 20c can be diagnosed as abnormal.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to optical serial transmission in which an input system and an output system of a process are connected through a single fiber, and output data and input data are loaded in the same frame on the fiber in a time-sharing manner. The present invention relates to an optical remote input/output device that enables localized detection and disconnection of fiber breaks and failures of input/output devices, thereby increasing the reliability of the system.

[Background of the Invention] A conventional device is known, for example, as described in Japanese Patent Application Laid-Open No. 55-156436, which bypasses the terminal when the terminal fails. However, in a method where output data to the process and input data from the process are time-shared in the same frame, the data input to the process control device is sent (output) from the process control device rather than the input data of the terminal because of the bypass. There is a problem in that the data is returned as is, and as a result, a specific signal is input and an erroneous calculation is performed based on that signal.

[Purpose of the invention]

An object of the present invention is to eliminate the drawbacks of the prior art described above, and to solve the problem in the case of optical fiber breakage or failure of optical input/output equipment by using a method in which output data to a process and input data from the process are loaded on the same frame in a time-sharing manner. An object of the present invention is to provide an optical remote input/output device that can immediately detect whether a terminal has failed and disconnect it.

[Summary of the invention]

The present invention provides RAS data as a part of the transmission data output from the process control device to each terminal, and each terminal
The RAS data received during JPt is rewritten and sent to the next stage together with the process data.

When the MPU is abnormal, the signal is bypassed by VDT operation, and when the fiber is disconnected or the optical receiving module is abnormal, the RAS data and process data are transmitted to the next stage without updating the RAS data.

Therefore, the process control device side checks whether or not it has been rewritten based on the received RAS data, and depending on the content, the abnormality
It is possible to immediately diagnose abnormal stress points.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. Second
The figure shows an example of the system configuration of a data optical communication system. In the figure, a process control device (hereinafter referred to as PC) is connected to a serial transmitter 12 and a serial receiver 13 via a bus 2, and optical fiber transmission/reception lines 19a to 19.
are connected in series via e. Optical remote input/output bag fil 20 a to 20 d on the terminal side is process 10
A to 10d are connected to each other via data buses 98 to 9d, respectively.

The serial transmitter 12 on the PC side, which is the starting point, cyclically generates a frame 21a as shown in FIG. 3, and sends it to the optical fiber transmission line 19a. FIG. 1 is a block diagram showing details of an optical remote input/output device 20a as a terminal example according to the present invention.

20b to 20dT are also the same, and 20a will be explained below. Optical remote input/output bag 5120a is 0/E1
00a, serial-parallel converter 101a.

Register RE G 1 a, Register RE G 2 a
, gate circuit 104, 5a, E10106a, watchdog timer WDTI when MPU is abnormal, watchdog timer VDT2 when line is disconnected. It is composed of an alarm output RY 109a, a display 110a, and a logical sum 108a.

FIG. 3 shows the structure of transmission data sent from the PC and each optical remote input/output device. FIG. 4 shows the flow of signals. The details of the present invention will be explained using FIGS. 1 to 4 below. In the optical remote input/output device 20a shown in FIG. 1, the optical serial signal on the optical fiber transmission path is O/E10.
0a, 5dP101a, parallel signals are generated, 1
Data slots DATA a , DATA b , DATA of frame 21 a in FIG. 3 are stored in the buffer of frame 01 a.
c, stored as DATA d. Then, DATAa in the buffer is stored in REGla and process 1
It can be read from 0a. On the other hand, the process data from the process 10a is stored in REG2a as FBa, and as shown in FIG. 4, DATA b - DATA d is rewritten to FBa instead of DATA b - DATA d
P4JS101a and put it on the frame 21b.
, gate 105a.

It is sent to the optical fiber transmission line 19b via E10106a. In the next-stage optical remote input/output device, frame 2
1b and REGl data slot DATA b.
After storing the process data FBb in DATAb, the process data FBb is rewritten into DATAb and sent out to the optical fiber transmission line 19c together with other data slots as a data frame 21c. Optical remote input/output device 20 below
Similarly, reception is received at c and 20d.

The data is transmitted to the serial transmission device 13 as a frame 21e carrying each process data as shown in FIG. 3(e). That is, it shows that the process data of four units is transmitted through optical fibers connected in series in one direction.

However, in the configuration shown in FIG. 2, calculations or system failures due to incorrect data may occur due to malfunctions such as failure of the optical mote input/output device or disconnection of optical fibers, but the present invention can prevent this. A specific example of relief in the event of a failure will be explained below.

FIG. 5 shows the data format sent out from the serial transmission device 12. That is, RAS data for abnormality diagnosis of each terminal is provided in the fourth word of each command data DATA a and DATA d for each process. RAS
As data, 1 is assigned to bits 0 to 2, respectively, indicating MPU normal/abnormal, one line normal/abnormal, and no/presence of bypass command. The MPU normality/abnormality is a signal indicating whether the operation of the S-P conversion circuit shown in FIG. 1 is normal or not, and the line normality/abnormality is a signal indicating whether the received signal is normal or not (including line disconnection). Bypass command presence/absence is a command signal used when it is desired to bypass each process. Next, using Figure 6, (1)
The operation when line abnormality and (2) MPU abnormality occur will be explained.

FIG. 6 shows changes in RAS data when an abnormality occurs. First, a case where the line is disconnected at point M will be described. The serial transmission device 12 sets "1", which is an error signal, in the RAS data part as shown in signal A and transmits it. Since the optical remote input/output devices fl 20a to 20b are normal, the transmission data B and C are data that has been rewritten to It I II → 1 (O11) with respect to the RAS data of their own data slot. However, at point M The optical remote input/output device 20c diagnoses the disconnected nozzle as a reception abnormality, and sends it to the backup by the watchdog timer WDT2.Since the final stage 20d is normal, its own R
The AS data is updated and sent to the next stage. Therefore, the received data input to the serial transmission device 13 is not "0" only for the third RAS data as shown in E, but from 20b to 2
It is possible to diagnose a line abnormality between Oc.

Next, a case where an MPU abnormality occurs will be explained. Assuming that the S4-)P conversion circuit of 20c of the optical remote input device fails, a watchdog timer error will occur, the WDTI shown in Figure 1 will operate, and the data received by 20c will be bypassed as is, so the transmission of 20b will be interrupted. The data is input to 20d without the third RAS data being updated.In 820d, the fourth RAS data is rewritten, so the final data becomes E in (3).The third RAS data allows the serial transmission device to 13 is 2
0c MPU abnormality can be immediately diagnosed, and calculations based on incorrect data can be prevented.

Figure 7 shows the 84-+P conversion circuit of the optical remote input/output device.

1 is a processing flowchart of a processor used in one path. In FIG. 7, block A performs initial setting of each constant when the power is turned on, and block B performs reception processing of input serial data. Block C enters backup mode and jumps to block O if reception is not completed even after a certain period of time has elapsed. If it is not the backup mode, it is determined in block D whether reception is normal or not, and if reception is abnormal, reset processing is performed in block E and re-reception is performed. When reception is normal, block F executes memory write processing to store the received data in REG1, and block G executes memory write processing to store the received data in REG1.
Memory read and block H to send the contents of 2
In block J, RAS data is set, and in block J, transmission processing is executed. The block determines whether it is in bypass mode or not, and if not, the watchdog timer (VDT)
The initial value of is set in block L to prevent a VDT error from occurring. In the case of bypass, the initial value of the WDT is not updated, so the VDT operates, and when it is not bypass, the process jumps to the next block and continues reception processing. In the backup mode, jump to block 0, read the contents of REG2 in block P, set the MPU error bit “1” of the RAS data to “0”, and then jump to block J again.
Jump to and repeat the sending process.

In the case of an MPU abnormality, it is bypassed as described above, so it is automatically disconnected, but if you want to disconnect any force point, you just need to set 111 It in the bypass command of the RAS data.

As described above, by providing RAS data as part of the transmitted data and providing the optical remote input/output device with a RAS data setting function, abnormal locations can be easily detected.

〔Effect of the invention〕

According to the present invention, even if the output data to the process and the input data from the process are loaded on the same frame in a time-sharing manner, it is possible to diagnose which terminal is normal or not based on the failure factor data even in the event of a failure on the terminal side or fiber breakage. can be marked, there is no erroneous calculation, and the terminal side can be disconnected, which has the effect of improving system reliability. Furthermore, the system configuration allows transmission and reception through a single optical fiber, which is economical.

[Brief explanation of drawings]

Fig. 1 is a detailed block diagram of an optical remote input/output device according to an embodiment of the present invention, Fig. 2 is a block diagram showing an example of a data communication system, Fig. 3 is an explanatory diagram of the structure of transmitted data, and Fig. 4 is a signal 5 is an explanatory diagram of the flow, FIG. 5 is a transmission data format, FIG. 6 is a detailed explanatory diagram of the present invention, and FIG. 7 is a processing flowchart. 1... Process control device, 2, 9... Pass, 10.
...Process, 12,13...Serial transmission device, 1
9...1b f 1e < Next 4th figure (CL) 1000-F frame @ A3+ = Evening (b) Rate 6th

Claims (1)

[Claims] 1.Regarding a transmission system that uses an optical serial transmission device for data transmission between a process host control device and multiple terminal-side control devices, the output of the optical serial transmission device of the high-level control device is the starting point and the input is the end point. In process data transmission in which lower-level control devices on the terminal side are connected in series using an optical remote input/output device and an optical fiber transmission line, RAS is used as part of the data sent from the higher-level control device to each lower-level control device.
data is provided, and each optical remote input/output device updates each RAS data with respect to this RAS data when it is normal.
This optical remote system is characterized by the ability to detect any failure point by bypassing the received data to the next stage in the event of an abnormality, and by having the next stage optical remote input/output device update and send the RAS data in the event of an abnormality in the optical fiber transmission line. Input/output device.