JPH08272407A - Monitoring device for programmable controller - Google Patents

Abstract

PURPOSE: To instruct and input a proper control instruction from a monitoring device to a PC executing a sequence control program and to correctly display the operating state of the PC. CONSTITUTION: A display table 3a which stores the control instruction displayed on the CRT 4 of the monitoring device 11, and an operating condition table 3b which stores the operating condition of the control instruction set on the PC 12 are provided, and the priority order of a key-inputted control instruction in the monitoring device 11 or the one in which a new operating condition is established is compared with that of the control instruction set in an on-state in the display table 3a, and the control instruction of high-order is displayed on the CRT 4. Also, when the priority order of the key-inputted control instruction is higher than that of the control instruction set in the on-state in the display table 3a, the key-inputted control instruction is outputted to the PC 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a programmable controller (hereinafter referred to as a PC) for performing sequence control of a control device.
Say ) Relates to a monitor device for monitoring the operating state.

[0002]

2. Description of the Related Art A system including a PC is widely used for sequence control of a control device in a factory or the like. A sequence control program created based on the sequence control processing procedure is given to the PC in advance. In this sequence control program, the step condition of each operation step constituted by the ON / OFF state of the output terminal of the PC in each operation step, the ON / OFF state of the input terminal of the PC, the time measured by the timer, and the like, and It includes a control command whose operating condition is a predetermined on / off state of the input terminal of the PC. The detection means of the control device is connected to the input terminal of the PC, and the drive device of the control device is connected to the output terminal of the PC.

According to a given sequence control program, the PC advances to the next operation step when the on / off state of the input terminal and the like satisfies the stepping condition in each operation step, and changes the on / off state of the output terminal. The on / off state set in the operation process is switched. When the ON / OFF state of the input terminal matches the operating condition of the control command such as process start, pause, process stop, 1-cycle operation, forced stepping or process reset, the control command corresponding to the operating condition is issued. Run. In order for the control device to execute the desired operation, it is necessary to monitor the execution state of the sequence control in the PC, and it is checked in advance whether the PC operates properly based on the supplied sequence control program. There is also a need.

Therefore, conventionally, a monitor device is connected to the PC. In this monitor device, as shown in FIG. 5, for example, a program memory 62, a monitor result storage memory 63, a CRT 64, an input device 65 such as a keyboard, an external storage device 66 and an interface 67 are connected to a CPU 61 via an internal bus. It is a thing. The monitoring device is P
When the C72 is in operation, the operating state of the PC 72 that is executing sequence control is monitored, the result is stored in the monitor result storage memory 63, and then the control instruction currently being executed by the PC 72 is displayed on the CRT 64. During maintenance of the PC 72 such as debugging of the sequence control program, the control device receives an instruction input of a control instruction via the input device 65 and outputs the instruction input to the PC 72.

[0005]

However, in the conventional PC monitor device, when the PC that is executing the sequence control program is in operation, the monitor device changes from the PC to the PC.
Could not give a control command to. Therefore, for example, when the monitor device is installed at a position away from the position where the control device and the PC are installed, the PC cannot be temporarily stopped from the monitor device. There is a problem in that it is impossible to instruct the PC to issue a control command different from the existing control command to the PC, so that the PC cannot quickly execute an appropriate control command.

It is an object of the present invention to allow a monitor device to instruct and input a control command to a PC that is executing a sequence control program, to allow the PC to quickly execute an appropriate control command, and An object of the present invention is to provide a monitor device that can accurately display the operating state.

[0007]

The present invention relates to a monitor device which is connected to a PC for executing sequence control of a control device based on a sequence control program composed of a plurality of operation steps and which monitors the operating state of the PC. ,
Control command means for receiving an instruction input of a control command in the sequence control program; priority comparison means for comparing the priority order of the control command instructed from the control command means with the priority order of the control operation being executed by the PC; When the priority of the control command instructed and input from the control command means is higher than the priority of the control operation being executed by the PC in the comparison result of the priority comparison means, the control command instructed and input from the control command means is connected to the PC. And a control command output means for outputting to.

[0008]

According to the present invention, when the control command of the sequence control program is instructed while the PC is executing the sequence control, the priority order of the instructed control command and the PC
Compares the priority of the control instruction currently being executed, and if the priority of the control instruction instructed and input is higher than the priority of the control instruction currently being executed, the control instruction is sent to the PC.
Output to. Therefore, even when the PC is executing the sequence control of the control device, the monitor device can instruct the PC to issue a control command.

[0009]

1 is a block diagram of a monitor apparatus according to an embodiment of the present invention. The monitor device 11 is configured by connecting a program memory 2, a work memory 3, a CRT 4, a keyboard 5, a mouse 6, an FDD 7 and a PC interface 8 to the CPU 1 via an internal bus 9. The program memory 2 stores a program that defines the processing operation of the CPU 1. The programs stored in the program memory 2 include a program 2a for creating a sequence control program, a program 2b for setting operating conditions of PC control commands during monitoring processing, and a screen during monitoring processing and monitoring processing. There are a program 2c for displaying, a program 2d for accepting an input operation of a control command of the PC during the monitor processing, and the like.

The work memory 3 stores data input / output in the processing operation of the CPU 1. A part of the work memory 3 includes a display table 3a that stores the input state of the control command during the monitoring process and the monitoring process, and an operation condition table 3b that stores the relationship between the control command of the PC 12 and the operating condition. It is stored. CRT4
Displays a display screen described later. The keyboard 5 and the mouse 6 are operated when designating an input field on the display screen or inputting data settings. The FDD 7 writes the storage content of the work memory 3 storing the control data to the floppy disk. The PC interface 8 is the PC 12
Sends and receives data to and from.

As the monitor device 11, a general personal computer can be used. In this case, some or all of the programs stored in the program memory 2 are loaded from the floppy disk via the FDD 7. Further, the work memory 3 is configured in the RAM. Further, the PC interface 8 is, for example, RS23.
A general-purpose interface such as 2C is used.

FIG. 2 is a diagram showing a set state of operating conditions of control commands in the PC. During execution of the sequence control, the PC 12 executes each control command of process start, temporary stop, process stop, one-cycle operation, forced stepping and process reset according to a predetermined combination of ON / OFF states of the input terminals. For example, in the example shown in FIG. 2, when the input terminal X10 of the PC 12 is turned on and the operation condition of the process start instruction is satisfied, the PC 12 starts executing the sequence control program and is included in the sequence control program in each operation process. When the stepping condition is satisfied, the step moves to the next operation step. When the operating condition of the temporary stop instruction is satisfied, the sequence control program being executed is temporarily stopped. When the operation condition of the process stop instruction is satisfied, the sequence control program being executed is stopped. When the operating condition of the 1-cycle operation instruction is satisfied, the sequence control program is executed for only 1 cycle. When the operating condition of the forced step instruction is satisfied, the step proceeds to the next operation step regardless of whether the step condition is satisfied.
When the operation condition of the process reset command is satisfied, the count values of the timer and the counter included in the stepping condition are cleared, and all outputs are turned off to stop the operation.

More specifically, the PC 12 has an internal relay corresponding to each control command, and when the operating condition of any of the control commands is satisfied, the corresponding internal relay is selectively set, The state of satisfaction of the operating condition is stored. The operating condition of this control command can be preset and input in the monitor device 11. The operating condition of each control command set and input in the monitor device 11 is stored in the operating condition table 3b. Note that these control commands are given priorities in the order of process reset, process stop, temporary stop, one-cycle operation, process start, and forced stepping. Therefore, for example, even if the operation condition for the process start is satisfied after the operation condition for the one-cycle operation is satisfied, the PC1
2 does not perform process activation.

FIG. 3 is a view showing a display screen during operation monitoring in the monitor device. During operation monitoring for monitoring the operating state of the PC 12, the monitor device 11 displays the display screen 21. This display screen 21 shows the progress column 2
2, a step condition column 23 and a control command key 24. The progress state column 22 indicates the ON / OFF state of each output terminal of the PC 12 by taking the operation process on the horizontal axis. The step condition column 23 displays the step condition in the sequence control program for the operation process currently being executed by the PC 12. The control command key 24 includes a process start command key 24a, a temporary stop command key 24b, and a process stop command key 2.
4c, a 1-cycle operation command key 24d, a forced step command key 24e, and a process reset command key 24f.
These control command keys 24 are operated when the monitor device 11 issues a control command to the PC 12 that is executing the sequence control program, and also displays the control command that the PC 12 is executing. The operation command key 24 can be operated by the mouse 6.

FIG. 4 is a flowchart showing a processing procedure at the time of the monitoring processing of the monitor device. During the monitoring process, the CPU 1 first determines whether or not the control command key 24 has been operated on the display screen 21 (s1). If the control command key 24 has not been operated, the CPU 1 inputs from the PC 12 at a predetermined timing. The on / off state of is read (s2). The CPU 1 searches the operating condition table 3b for the read state of the input terminal (s3), and if there is a control command that satisfies the operating condition, searches the display table 3a for a control command in the ON state. Yes (s4, s5). When there is a control command in the ON state in the display table 3a, the CPU 1 compares the priority order of the control command for which the current operation condition is satisfied with the priority order of the control command for the current ON state (s6), and the current operation condition is satisfied. When the priority order of the control command is higher, the control command for which the operating condition is satisfied this time is turned on in the display table 3a, and the control command which has been in the on state until then is turned off to update the display table 3a. (S7, s8).
After that, the CPU 1 displays the operation command key 24 of the display screen 21 according to the contents of the updated display table 3a (s9).

When the control command key 24 is operated, it is searched whether or not there is a control command in the ON state in the display table 3a (s11). If there is a control command in the ON state in the display table 3a, The CPU 1 compares the priority of the control command input by the key with the priority of the control command currently in the ON state (s12), and if the priority of the control command input by the key is higher, the control is executed. The command is output to the PC 12 (s13, s14). As described above, the PC 12 stores the control command to be executed in the internal relay, and the CPU 1 instructs the PC 12 to set the internal relay corresponding to the keyed control command. Is output. After this, the CPU
1 is the above-mentioned display table update processing (s8), and
Display processing (s9) is executed. If the priority of the control command keyed in is lower, the control command output process, the display table update process, and the display process are not performed.

By the above processing, the operating state of the PC 12 during the execution of the sequence control can be monitored by the monitor device 11, and the monitor device 11 can monitor the PC 1 as well.
A control command can be instructed to 2. Moreover,
In the monitor device 11, when a control command having a lower priority than the control command currently being executed by the PC 12 is instructed, the control command is not output to the PC 12, so
It is possible to prevent the malfunction of 12 in advance. Also, P
Only when the operating condition of the control command having a higher priority than the control command currently being executed in C12 is satisfied, the display content on the display screen 24 is changed, so that the operating state of the PC 12 can be accurately displayed.

[0018]

According to the present invention, it is possible to instruct the PC, which is executing the sequence control, only the control command having a higher priority than the control command being executed by the PC from the monitor device and the PC. It is possible to provide a monitor device suitable for a control system for remotely monitoring a PC, which can accurately display the operating state of the PC.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a monitor device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a setting state of operating conditions of a control command in a PC monitored by the monitor device.

FIG. 3 is a diagram showing a display screen during operation monitoring in the monitor device.

FIG. 4 is a flowchart showing a processing procedure at the time of monitoring processing in the monitor device.

FIG. 5 is a block diagram showing a configuration of a conventional monitor device.

[Explanation of symbols]

 2-Program memory 3-Work memory 4-CRT 11-Monitor device 12-PC 21-Display screen 22-Progress status column 24-Operation instruction key

Claims (1)

[Claims] 1. A programmable controller for executing sequence control of a control device based on a sequence control program configured by a plurality of operation steps,
In a monitor device that monitors the operating state of a programmable controller, a control command unit that receives an instruction input of a control command in a sequence control program, a priority order of control commands instructed from the control command unit, and a control operation being executed by the programmable controller. And the priority order of the control command instructed by the control command means in the comparison result of the priority order comparison means is higher than the priority order of the control operation being executed by the programmable controller. A monitor device for a programmable controller, comprising: a control command output unit that outputs a control command input from the control command unit to the programmable controller in this case.