JPS60685B2 - online maintenance equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an online maintenance device for a cyclic sequencer without branch instructions.

Conventionally, in this type of general control system, a central desk has the device-side operation and central automatic operation modes of field equipment, and a series of automatic operations are performed based on the commands from the central desk.

Moreover, when stopping the operation of any device in a series of sequence blocks, it was possible to stop the operation independently only on the device side. Therefore, when it is desired to change a program without stopping the sequencer, the program change becomes effective by arbitrarily freezing the affected equipment during the program change without disrupting the sequence.

Then, at the end of the program change, the frozen state is released only after sequence operation becomes possible with that program. Conventionally, this independent operation was performed on the field equipment side, and since the equipment side was made independent,
There were also situations where a series of sequences were automatically operated. However, the conventional method described above does not consider setting the output section on and off online separately from the program, and it is possible to do so only by remote control from the field equipment or central desk. Seem.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an online maintenance device for a sequencer that can automatically operate a sequence and remotely turn it on and off using only a program device that sets and monitors a sequence program.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an online maintenance device for a sequencer according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of one embodiment. 1 in FIG. 1 is a calculation unit (hereinafter referred to as CPU) that generates sequence calculations and control commands for the input/output unit,
Further, 2 is a program memory that stores commands to be sent to the CPUI. 3 is a programming device.

This program device 3 monitors the CPUI, writes programs into the program memory 2, outputs them, and forcibly turns on and off the input/output section 4. This input/output section 4 is for exchanging signals with process equipment. In addition, 5 is CP
This is an input/output bus from the UI, and 6 indicates a program input/output signal cable. FIG. 2 is an external view of the programming device 3 that performs online maintenance operations.

That is, it shows the operation display section of this programming device 3. 7 in FIG. 2 is a mode switch.

The mode switch 7 is set to program write “WRT”.
”, program reading “READ”, monitor “MON” which performs various online monitoring, and maintenance “MTN” which allows the program device 3 to forcibly control the output unit independently of the program. ing. A freeze display section 8 is provided below the mode switch 7.

The freeze display section 8 displays the start of the forced setting of the output section by the program device 3, and indicates that the lamp is turned on to indicate "freeze state" and that the lamp is turned off to indicate "freeze release". Command units 9 and 10 are arranged below the freeze display unit 8. The command units 9 and 10 are push-pin switches, and issue commands to turn on and off the output units 11 and 12. After the settings are made using the output units 11 and 12, the push button switch of the command unit 9 or 10 is pressed. For example, as shown in the figure, the output unit 11 has control target keys marked with "1", "0", "M", "T", and "input", "output", etc., respectively. ...etc.

Further, the output section 12 is in the form of a numeric keypad, with "0"
” to “9” and “C” for cancellation.
are marked with letters of the alphabet. On the other hand, 13 indicates an output display section.

Now, for example, when it is desired to forcibly turn on the output "0" of the output section 11 and the output "10" of the output section 12, the mode switch 7 is first set to maintenance "MTN". Next, press the freeze display section 8. This results in
The freeze display section 8 lights up, indicating a frozen state, that is,
Displays freeze operation enabled status. Next, among the control target keys of the output unit 11, output "0" is pressed.

Furthermore, the numeric key switch of the output section 12 is set to "1" and "0".
” to set it to “10” and then press the command unit 9. By doing this, the output display unit 13 will display the output “010, phase, 1”. be. Among these, "Freeze" is displayed when the current output is "0".
10" is forcibly frozen like "1".

Furthermore, if you want to forcibly freeze other outputs, you can continue to operate the output display section 13.

In this way, when the forced output freeze setting is completed, it is necessary to send the information that has been frozen so far (that is, the operation information after the freeze operation on the freeze display section 8 is also performed after the display lamp lights up) to the CPUI, so EXC Press key 14. The subsequent operations will be described from FIG. 3 onwards. Note that 15 is a romantic key, and keys are arranged as many as the number of instructions dedicated to the sequencer in this invention.

FIG. 3 is a diagram showing a program chart executed by the CPU when executing online maintenance processing. In FIG. 3, 16 is a normal sequence program (main program), and 17 is an end indicating the end of the sequence program This indicates that the command is included as a program.

Further, 18 indicates a state in which a corresponding program (subprogram) according to a request from the program device 3 in FIG. This indicates that the command always ends at the command end. FIG. 4 is a flowchart for explaining the flow of the CPUI operation based on the program chart shown in FIG.

In FIG. 4, when the end command 17 of the sequence program 16 appears in step A, the CPU always checks to see if there is a request from the program device 3 (requests from the program device 3 are sent to the CPU for each request). ),
In step B, the CPUI looks at the request flag and moves the operation to the corresponding program address. If there is no request from the program device 3, the program jumps to the step date, sets the program address to the initial address (usually address 0), and repeats the sequence program 17 again.

Therefore, returning to step B, when there is a request from the programming device 3, the request has a monitor mode "MON" and a maintenance mode "MTN", and the maintenance mode "MTN" has a "program change request" and a "program change request". There is a request for output freeze. When a monitor request is made, the corresponding program (monitor operation program) shown in FIG. 3 operates in step C, and has the function of finally outputting and displaying to the program device 3 via the CPU. In addition, if the maintenance mode is to write a program, the work moves from the program device 3 to the CPUI to the program memory 2, and as a result, the program for each instruction set from the program device 3 is stored in the program memory 2. (Step D).

Next, the process moves to step E, and if the output freeze is requested (set the freeze set from the program device 3,
In either case of a reset, each time the EXC key 14 is operated, the CPUI accepts it), the CPUI reads the contents of the output freeze memory in the program device 3 through the program input/output signal cable 6, and writes it to the image memory in the CPUI. do something

As described above, in this embodiment, the steps of the program device 3 are explained.

An o-gram (subprogram) is shown as an example of performing these operations. It is also possible to process all requests from the program device 3 using hardware. Next, when this subprogram ends, there is always an end command at the end, that end command is detected in step F, and if it is an end command, step G
When the end command is detected in step 3, an inquiry is made as to whether or not there is a request from the program device 3.

In this respect, it is functionally the same as the end command 17 (main program).

After that, it returns to the initial address on the step date and repeats the sequence again. Next, the operation of the CPU in response to freezing will be explained with reference to FIG.

This FIG. 5 is for explaining the functional operation of the freeze output of online maintenance, and 3 in this FIG. 5 is a program device. 1 is a CPU.

Also, data storage areas 19a and 2 are data storage areas for storing a freeze command based on the operation of the program device 3 and data of "1" when the freeze is on and "0" when the freeze is off. The capacity of the freeze command flag and freeze data is equivalent to the number of output points. Therefore, for output ○n, freeze command flag o
n and freeze data ○n always exist in pairs.

The freeze command flag and freeze date in the program device 3 are stored in data storage areas 21 and 22 in the CPU 1 as images. That is, through the input/output bus 5, the main program (
That is, data transfer is performed when there is a freeze request from the program device 3 at the end command of the sequence program.

Here, we are not only transferring data to the freeze setting area, but also
It is assumed that data transfer is performed for the full amount of data in the data storage areas 19a and 20 of the program device 3.

In other words, the contents of the data storage area 19a are directly mapped to the data storage area 21.

Further, the contents of the data storage area 20 are mapped directly to the data storage area 22. The series of data transfer operations are all performed by the corresponding program 18 in FIG. 3, and when the operation is completed, the CPU checks again with the end command of the command flag 19 to see if there is a request from the program device 3. And if there are no inquiries,
Program execution is resumed from the initial address of the main program. Therefore, when an output command appears in a normal main program, that is, a sequence program, there are cases in which the current calculation result is output as is, and cases in which it is forcibly turned on and off by a freeze command.

23 in Figure 5 is the result accumulator (Re
sultAccmm (hereinafter referred to as RA) is a 1-bit accumulator that always holds the result of the operation by the sequence program, and 24 is the operation unit by the sequence program, which executes logical product, logical sum, etc. It has a function to hold the results in RA23.

25 is an on/off freeze data output Dn corresponding to the output ○n, and 26 is a freeze command flag Fn corresponding to the output 0n that determines whether the output needs to be frozen to the state of the output ○n. It is.

27 is an AND gate that executes the AND of the output of the RA 23 and the negation Fn of the freeze command flag 26, that is, RA.Fn. 28 is also an AND gate that executes the AND of the freeze data output and the freeze command flag, that is, Dn and Fn.

The outputs of the AND gates 28 and 27 are output to an OR gate 29. Oh Gate 2
9 executes RA.Fn+Dn.Fn, and transmits the output to the signal line 30 and input/output bus 5, thereby becoming data to the output section. A signal line 31 is connected to the input/output bus 5 and is used to transmit a strobe pulse 32.

This strobe pulse 32 is applied to the signal line 3 at the time of output command.
The output of the OR gate 29 (data to the output section) transmitted to the address line 3 of the output
This shows the strobe pulse set to 3). Reference numeral 34 indicates a control section, and this sequencer creates control timing.

Next, the operation of the CPUI will be explained. For example, the operation of an output command in which the controlled object is output ○m will be explained.

First, an address signal is sent to the output section via the address line 33 and the input/output bus 5 corresponding to the output ○n. At the same time, the freeze data and freeze command corresponding to the output OM are transferred to the data storage area 2.
Extract the contents (1 bit each) from 1 and 22,
Freeze data output 25, freeze command flag 26
Output as . If the freeze command flag Fn=0, that is, there is no freeze command for output ○n, the output of the AND gate 28 will be "0",
The contents of RA23 are the OR gate 29 and signal line 30.
is transferred as output data through

In other words, output by a normal program will be executed.

If the freeze command flag 26 is (Fn=1), that is, a freeze command has been issued for output Data output 25
The contents themselves are transferred as output data through the OR gate 29 and signal line 30, and the output section is set independently of the program. In other words, regardless of the presence or absence of freeze, the output command of the program always sets the generation of the strobe pulse 32 transmitted to the signal line 31 and the output data transmitted to the signal line 30' for the output ○n. Become.

In this embodiment, the end command of the main program is used to check the presence or absence of a request from the program device 3, but in the case of a sequencer with an interrupt function, it is possible to accept the request in the middle of the main program. .

However, in this case, it is necessary to save the current sequence state and the return destination of the interrupt program, and the hardware is exactly the same as having a spectral skin command, resulting in a complicated hardware configuration.

As described above, according to the present invention, since the program is configured to be able to independently turn on and off any output section using the freeze function of the program device of the sequencer, it is not necessary to go to the field equipment and check the field equipment. There is no need to turn it on and off, and by operating the on-site equipment independently, it is not impossible to automatically operate a series of sequences, and any equipment can be operated separately from the automatic operation of a series of sequences.

What's more, the program can be changed while the frozen state is maintained, and once all program changes have been completed, the sequence can be run using the newly changed program. It is possible to realize this.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the overall configuration of the online maintenance system of the present invention, Fig. 2 is a diagram showing the operation surface of the program device in the above online maintenance device, and Fig. 3 is an online maintenance process by the above online maintenance device. FIG. 4 is a flowchart showing the operation of the CPU in the above-mentioned online maintenance device; and FIG. 5 is a flowchart showing the functional operation of the CPU in the above-mentioned online maintenance device for the freeze output of online maintenance. It is a diagram. 1... Arithmetic unit, 2... Program memory,
3...Program device, 4...Input/output section 5
...Input/output bus, 6..." Program input/output signal cable, 7...Mode switch, 8...Freeze display section "11, 12...Output section, 13...Output display 15...Command keys. In the drawings, the same reference numerals indicate the same or equivalent parts.
Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. In a sequencer using a cyclic control method that cyclically controls a terminal without having a branch instruction, a program device in which programs and data are set, and a data output freeze generated from this program device. An arithmetic unit that interlocks when an output command is generated and sets and resets any output from the program device while online by separating it from the logic of the program, and a program that stores command information for this arithmetic unit. The programming device includes a mode switch for switching to a predetermined mode, a freeze display section for displaying the start of forced setting of the output section and indicating the presence or absence of a freeze state,
1. An online maintenance device comprising: a command section that outputs an off command; a controlled object selection means; and an output display section that displays the operating states of the mode switch, the command section, and the controlled object selection means. 2. The calculation section includes a data storage area that stores the freeze command flag and freeze data for each request from the programming device at the end of the main program, an accumulator that always holds the calculation results of the main program, and the calculation of this accumulator. A result accumulator that holds the results, and a function that determines whether or not it is necessary to freeze the output section in response to the output, executes output by a normal program when freezing is not necessary, and freezes the above when it is necessary to freeze. 2. The online maintenance device according to claim 1, further comprising means for transmitting data as output data to an output unit.