JPS5853771B2 - How to initialize a terminal control device in a distributed control system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a distributed control system for control computers, and in particular, for periodically collecting and distributing data from a control computer to a large number of terminal control devices distributed far away via transmission paths. The present invention relates to a method for initializing a terminal control device in a distributed control system to obtain control information necessary for the system.

In a distributed control system consisting of a control computer and a large number of terminal control devices distributed far away from the control computer via a common control device and a transmission path, a microprocessor is used as the terminal control device to control process-side sensors. / Actuators and various equipment signals are transmitted to various input/output devices (hereinafter referred to as I).
10) is controlled to periodically collect and deliver data.

The microprocessor controls the I10 module to periodically collect and deliver data using control information stored in the microprocessor memory, but such control information must be created by some means at the time of system initialization. .

In general, (1) control information is sent from the control computer to each I10 module in the terminal control device;
2) It is known that control information to control the I10 module is set on each 10 module flint board only by a terminal control device without using a control computer, and the microprocessor is operated to import the control information.

However, (1) has the disadvantage that control information is sent to a plurality of terminal control devices at the time of system initialization (system start-up), which places a heavy burden on the control computer and increases the amount of transmission.

In addition, (2) is a controller) Since all information is set on each I10 module printed board, including information that depends on process-side signals, the amount of information that the printed board has is large, making the settings complicated, and the control information There was a drawback that the circuit for taking in was large.

An object of the present invention is to eliminate the above-mentioned drawbacks and to provide a suitable transfer of control information necessary for collecting and distributing data from a large number of terminal control devices distributed far from a control computer in a distributed control system for control computers. The present invention provides a method for initializing a terminal control device in a preferred distributed control system.

A feature of the present invention is that control information is divided into information that depends on the type of I10 module and information that does not depend on the type of I10 module, and the former information is set in the I10 module and is set at the time of system initialization (when the terminal control device power is restored or started). ), the microprocessor of the terminal control device performs each I
It specifies an address for each 10 module and reads the code in the I10 module, and creates control information so that the terminal control device can automatically access the I10 module for each type of I10, and the latter depends on the process side signal. Therefore, at the time of system initialization, the information is sequentially sent from the control computer to the terminal control device via the common control device and the transmission path.

As a result, according to the present invention, by simply creating control information from the code set on the I10 module printed board of the terminal control device at the time of system initialization, the terminal control device can automatically enter the data collection/delivery state.
The burden on the control computer can be reduced, and the amount of hardware of the terminal control device for importing control information can also be prevented from increasing too much.

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

FIG. 1 is a block diagram showing the configuration of a distributed control system for control computers to which the present invention is applied.

In Figure 1, 10 is a CPU (central processing unit).
Memory 1 is connected to U10 via interface bus 12.
1 and the adapter 24 of the common control device 200 are connected.

The microprocessor 20 , memory 21 , and transmission control module 23 are connected to the adapter 24 via the interface 22 .

The transmission control module 23 is connected to the transmission control module 33 of the terminal control device 301 via the transmission line 50.

The transmission control module 33 has an interface bus 32.
A microprocessor 30, a memory 31. and a plurality of I10 modules 401, 402 .・・・・・・
・is connected.

Note that the common control device 200 is connected to a plurality of terminal control devices 30L302.・
...is connected.

The operation of FIG. 1 in the above configuration will be explained.

Each terminal control device 301, 302゜...
Since the operation will be explained in the same way, the following will explain the terminal control device as 3.
01.

In the terminal control device 301, a plurality of I10 modules 40 are normally activated periodically by the microprocessor 30 based on the control information created at the time of system initialization.
1.402. It collects and delivers data by controlling...

Collection and delivery of this data is processed independently of the data of the CPU 10.

Common control device 20 for data collection and delivery requests from CPU10
Since there are various combinations of the 0 operation (processing procedure) and the transmission control operation (procedure), specific means will not be described here.

Here, only the system initialization method of the terminal control device will be explained in detail.

FIG. 2 shows a specific method for initializing the system of the terminal control device from a hardware perspective. . . . is a circuit diagram showing a concrete configuration limited to the 4010 portion as a representative of .

In FIG. 2, 350 is a slot decoder which selects the contents of the address bus 322 like a slot selection line 351.

The reason for specifying the slot address is that no matter which type of I10 module printed board is inserted into the slot, there is no need for an address decoder inside the printed board, so the amount of hardware can be reduced.

413 is a code setting device that sets information depending on the type of I10 module, and includes a buffer 411 and a resistor 41.
This is for loading a normal code onto the data bus 321 using 2a to 412n.

Further, 425 is a signal conversion circuit which manages data collection and delivery and places normal data on the data bus 321 via the buffer 421.

The timing for loading the code or data onto the data bus 321 is obtained by enabling the respective buffers 411 or 412 via the gates 410 and 420, and the switching timing is determined by inputting the gates 410 and 412 at the time of initialization of 324. Switching occurs when signals are added to the buffer switching line indicating that there is a buffer switching line, the slot selection line of the output of the slot decoder 350 of 351, and the lead line of 325 indicating that data is being taken into the data bus 321.

Therefore, two states are never captured at the same slot address.

Figure 2 shows a dual in-line code setting device.
A package type switch (commonly known as a DIP switch) was used, but in order to improve the reliability of code setting instead of a switch, the code was set by connecting the mode on the printed board with a jumper wire as shown at 413 in Figure 3. You may.

Further, since the code can be fixed depending on the type of I10 module, the code pattern can be printed on the printed circuit board as shown in FIG. 4, and the code setting can be simplified.

The aforementioned code setter and information depending on the type of I10 module to be set as a code pattern are required as shown in FIG.

That is, the I10 type is the input/output name of the I10 module inserted in the slot, and the number of addresses in the slot is the number of mounting points in the I10 module inserted in the slot, and is set in a bit pattern.

In addition, if there are many types of 5I10 modules that cannot be combined into a common code, and the number of bits to set the code increases, or if you want to reduce the amount of mounting hardware for setting the code on the printed board, we will use a code setting device and a code pattern. Set using consecutive numbers as shown in Figure 6.

Corresponding to this serial number, information that depends on the type of I10 module, that is, information in the same format as shown in FIG. 5, is stored in the memory space of the microprocessor memory 31 as shown in FIG. The information (number of bits) can be reduced in appearance.

In this way, the number of control information acquisition circuits in the terminal control device can be reduced.

Next, an example of the processing flow seen from the software for obtaining information depending on the type of I10 module regarding the system initialization method of the terminal control device when the information shown in FIG. 5 is set in the I10 module is shown in FIG.
As shown in the figure.

FIG. 8 is a processing flow for creating control information such as that shown in FIG. 9.

The processing flow shown in FIG. 8 will be explained block by block using FIG. 9 as well.

Here, in FIG. 9, AIB, DIB, AOB, and DOB are provided for each type of I10 and each stores an SCB, and when actually processing an I10 module, the same type of Ilo, for example, an analog input ( AI) is divided into blocks so that it can all be processed.

SCB is slot) (Slot) black, N, CPA, DA
It stores the control information for actually controlling the I10 module.

The CPA stores the gain, pulse width, etc., and contains specifications for controlling the sensors and actuators of the controlled process.

DA stores input/output data, and stores data corresponding to S lot.

Next, it will be explained in detail.

(1) S lot initial value settings: AIB, DIB, A
OB.

Initialization of the start address of DOB, SCB, CPA, and DAAI areas, initialization of the CPA and DA areas, and S
Initialize the lot number (same as S lot A).

(2) Read the code set on the I10 module printed board in the slot: 5lot 5lot 5lot
Read the code as shown in Figure 5 set in the I10 module inserted in the .

For example, assume that the code is I10 type: AI, N: 8.

(3) Divide blocks into 10 types, S lot
Create control information to control: If the read code is judged to be an AI by determining the I10 type, the AI
B+0 (others are DIR and AOB corresponding to I10 types)
, or in DOB), and then store SCB+O in
+0 to S lot number: O, SCB+1 to N: 8, S
Store CPA+0 in CB+2 and DA+0 in SCB+3.

Then, in order to create control information for the I10 module for the next S lot number, AIB (others are DIB, AOB, or DOB depending on the I10 type).
, S.C.B.

Update the CPA and DA addresses.

That is, AIB (others are DIR corresponding to I10 types).

Add 1 to AOB (or DOB), add 4 to SCB, and add N:8 to CPA and DA.

(4) If all S lots are completed or not, the process jumps to (5) if the 51st lot number is the final number, and if so, ends the creation of the control information.

(5) S lot update: Add 1 to the 5 lot number and jump to (2).

In this way, the control information shown in FIG. 9 is finally created by executing the S lot number of operations.

In addition, when creating control information from Figures 6 and 7, simply add the process of extracting from the serial number in Figure 6 to the code in Figure 7 by referring to the code in Figure 7 to (2), and the process described earlier will be performed. That's right.

As described above, when the processing flow shown in FIG. 8 is executed, control information as shown in FIG. 9 is generated, but regarding the CPA, only the area for the CPA is secured.

Therefore, the data necessary for this area has an incomplete gain or pulse width until it is sent from the CPU, so that data can be automatically collected and delivered only by the terminal control device, although it is incomplete.

Therefore, normal data collection and delivery processing can only be realized after the CPU sends out information on the use of point addresses in slots stored in the CPA, designation of unused points, and information on gain or pulse width (initialization is essentially completed at this point). .

) Therefore, since the terminal control device can create control information depending on the type of I10 module, the CPU
This has the effect that less control information is sent out, the load on the CPU at the time of initialization is reduced, and the amount of transmission sent out via the transmission path can be reduced.

Furthermore, since most of the I10 module can be controlled only by the terminal control device, there is an effect that the operation can be easily checked when checking the operation of the terminal control device alone.

As explained above, according to the present invention, the control information for controlling the I10 module of the terminal control device is
0 Since information that depends on the type of module can be divided into information created by the terminal control device and information that must be obtained from the control computer, the burden on the control computer at the time of initialization can be reduced and This has the effect of reducing the amount of transmission to be sent out, and also reducing the number of circuits for acquiring control information of the terminal control device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a distributed control system for control computers to which the present invention is applied, FIG. 2 is a circuit diagram showing the specific configuration of a part of the terminal control device in FIG. 1, and FIG. The figure is a circuit diagram showing another embodiment of the code setter set in the I10 module, Figure 4 is a circuit diagram showing an example of the code pattern set in the I10 module, and Figure 5 is a circuit diagram showing the code setter and code pattern. Figure 6 is a diagram showing the contents of the code setter and code pattern, Figure 7 is a diagram showing the contents of the memory, and Figure 8 is a diagram showing the processing flow executed by the microprocessor of the terminal control device. , FIG. 9 is a diagram showing control information created in the memory of the terminal control device. 30...Microprocessor, 31...
-Memory for microprocessor, 32...Interface bus, 33...Transmission control module, 301...Terminal control device, 401...
・Attendance module.

Claims (1)

[Claims] 1. A control computer, a common control device connected via an interface of the control computer, a transmission path extending from the common control device, and a plurality of devices connected to the transmission path. The terminal control device includes a transmission control module for coupling to a transmission line, a plurality of input/output modules coupled to a process, and a microprocessor and information for controlling the input/output modules. In a distributed control system that has a memory for a microprocessor to store data, the microprocessor sequentially controls a plurality of input/output modules, and collects and delivers data, among the information for controlling the input/output modules. Information that depends on the type of input/output module is set in the input/output module, information that does not depend on the type of input/output module is set in the control computer, and at the time of system initialization, the microprocessor of each terminal control device is set. specifies the address for each input/output module, loads the setting information in each input/output module into the microprocessor memory, and also transfers the information in the control computer via the common control device, transmission path, and transmission control module. 1. A method for initializing a terminal control device in a distributed control system, characterized in that control information is imported into the microprocessor memory and used to control a turnout module. 2. The input/output module according to claim 1,
It has a code setter for setting information, a gate circuit that outputs an address designation output on the condition that it is an initial time, and a buffer gate that reads the output of the code setter using the output of the gate circuit. A method for initializing a terminal control device in a distributed control system, characterized in that the microprocessor specifies an address for each input/output module and sequentially reads the set code. 3. Claim 2, wherein the code setting device is a dual inline package type switch.
A method for initializing a terminal control device in a distributed control system as described in Section 1. 4. The terminal control device in the distributed control system according to claim 2, wherein the code setting device is a jumper wire for setting the mode and code printed on the input/output module printed board. Initialization method. 5. The terminal control device in the distributed control system according to claim 2, wherein the code setting device is a code pattern corresponding to the type of input/output module printed on the output module printed board. How to initialize.