JP3456786B2 - Monitor device for programmable controller - Google Patents

Description

Description: 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 The present invention relates to a monitor device for monitoring the operation state of (1). 2. Description of the Related Art When performing sequence control of a control device in a factory or the like, a system including a PC is widely used. A sequence control program created on the basis of the sequence control processing procedure is given to the PC in advance. The sequence control program includes an on / off state of an output terminal of the PC in each operation step, an on / off state of an input terminal of the PC, a timer time of a timer, and the like; The control instruction includes a predetermined ON / OFF state of the input terminal of the PC as an operation condition. 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 proceeds to the next operation step when the ON / OFF state of the input terminal or the like satisfies the step 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 a control command such as process start, temporary stop, process stop, one cycle operation, forced stepping or process reset, a control command corresponding to the operating condition is issued. Execute. In order to cause the control device to execute a desired operation, it is necessary to monitor the execution state of the sequence control in the PC, and to check in advance whether the PC operates properly based on the supplied sequence control program. You also need. For this reason, a monitor device is conventionally connected to a 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. Things. The monitor device is P
During the operation of the C72, the operation state of the PC 72 that is executing the sequence control is monitored, and the result is stored in the monitor result storage memory 63. Then, the control command and the like that the PC 72 is currently executing is displayed on the CRT 64. Further, at the time of maintenance of the PC 72 such as a debugging process of the sequence control program, the PC 72 receives an instruction input of a control instruction via the input device 65 and outputs the input control instruction to the PC 72. [0005] However, in the conventional PC monitor, when the PC running the PC executing the sequence control program is operated from the monitor,
Could not be given a control command. For this reason, for example, when the monitor device is installed at a position distant from the position where the control device and the PC are installed, the PC cannot execute the emergency operation such that the PC cannot be temporarily stopped from the monitor device. There is a problem that a control command different from the control command being issued cannot be instructed from the monitor device to the PC, and the PC cannot quickly execute an appropriate control command. SUMMARY OF THE INVENTION An object of the present invention is to make it possible to input a control command from a monitor device to a PC that is executing a sequence control program, thereby enabling 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 an operation state. [0007] The present invention is connected to a PC that executes sequence control of a control device based on a sequence control program constituted by a plurality of operation steps, and monitors the operation state of the PC. In the monitor device,
Control instruction means for receiving an instruction input of a control instruction in a sequence control program; priority comparison means for comparing the priority of the control instruction instructed from the control instruction means with the priority of the control operation being executed by the PC; In the comparison result of the priority comparing means, when the priority of the control instruction input from the control instruction means is higher than the priority of the control operation being executed by the PC, the control instruction input from the control instruction means is transmitted to the PC. Output to the lower priority
When the control command input from the control command means is
And a control command output unit that does not output the control command to C. According to the present invention, when a control command of a sequence control program is input while a PC is executing sequence control, the priority of the input control command and the PC are controlled.
Compares the priority of the currently executed control instruction with the priority of the currently executed control instruction, and if the priority of the currently input control instruction is higher than the priority of the currently executed control instruction,
Output to Therefore, even when the PC is executing the sequence control of the control device, a control command can be instructed from the monitor device to the PC. FIG. 1 is a block diagram of a monitor device according to an embodiment of the present invention. The monitor device 11 is configured by connecting the program memory 2, the work memory 3, the CRT 4, the keyboard 5, the mouse 6, the FDD 7, and the PC interface 8 to the CPU 1 via the internal bus 9. The program memory 2 stores a program that defines a 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 a PC control instruction during monitoring processing, and a screen during monitoring processing and monitoring processing. There is a program 2c for displaying, and a program 2d for receiving an input operation of a control command of the PC at the time of monitor processing. The work memory 3 stores data input and output in the processing operation of the CPU 1. A part of the work memory 3 includes a display table 3a for storing a monitoring command and an input state of a control command during the monitoring process, and an operation condition table 3b for storing a relationship between a control command of the PC 12 and an operating condition. 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 contents of the work memory 3 storing the control data to a floppy disk. The PC interface 8 is a PC 12
Sends and receives data to and from As the monitor device 11, a general personal computer can be used. In this case, a part or all of the program stored in the program memory 2 is loaded from the floppy disk via the FDD 7. The work memory 3 is configured in a 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 setting state of operating conditions of a control command in the PC. During execution of the sequence control, the PC 12 executes control commands of process start, temporary stop, process stop, one cycle operation, forced stepping, and process reset by a predetermined combination of ON / OFF states of 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 command 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 step condition is satisfied, the process proceeds to the next operation step. When the operation condition of the temporary stop command is satisfied, the currently executed sequence control program is temporarily stopped. When the operation condition of the process stop command is satisfied, the currently executed sequence control program is stopped. When the operating condition of the one-cycle operation command is satisfied, the sequence control program is executed for only one cycle. When the operation condition of the forced stepping instruction is satisfied, the process proceeds to the next operation step regardless of whether the stepping condition is satisfied.
When the operation condition of the process reset command is satisfied, the count value of the timer and the counter included in the stepping condition is 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 an operation condition of any control command is satisfied, the corresponding internal relay is selectively set, whereby The state of satisfaction of the operating condition is stored. The operating condition of the control command can be set and input in the monitor device 11 in advance. 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 priority 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 of the process start is satisfied after the operation condition of the one-cycle operation is satisfied, the PC 1
2 does not execute the process start. FIG. 3 is a view showing a display screen at the time of monitoring the operation of the monitor device. At the time of operation monitoring for monitoring the operation state of the PC 12, the monitor device 11 displays a display screen 21. The display screen 21 displays the progress status column 2
2, a step condition column 23 and a control command key 24. The progress status column 22 displays the on / off status of each output terminal of the PC 12 by taking the operation process on the horizontal axis. The step condition column 23 displays a 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 pause command key 24b, and a process stop command key 2.
4c, a one-cycle operation command key 24d, a forced stepping 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 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 input terminal 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 state of the read input terminal (s3). If there is a control instruction that satisfies the operating condition, the CPU 1 searches the display table 3a for an ON-state control instruction. (S4, s5). If there is an on-state control command in the display table 3a, the CPU 1 compares the priority of the control command that has satisfied the current operation condition with the priority of the control command that is currently on (s6), and the current operation condition has been satisfied. If the priority of the control command is higher, the control command that satisfies the operating condition this time is turned on in the display table 3a, and the control command that has been on is turned off to update the display table 3a. (S7, s8).
Thereafter, the CPU 1 displays the operation command key 24 on the display screen 21 according to the contents of the updated display table 3a (s9). If the control command key 24 has been operated, the display table 3a is searched for an on-state control command (s11). The CPU 1 compares the priority of the key-input control instruction with the priority of the control instruction that is currently ON (s12). If the priority of the key-input control instruction is higher, the control is performed. 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 a command indicating that the internal relay corresponding to the key-input control command should be set. Is output. After this, the CPU
1 is a process of updating the display table (s8), and
A display process (s9) is executed. If the priority of the key-input control command is lower, the control command output process, the display table update process, and the display process are not performed. According to the above processing, the operation state of the PC 12 which is executing the sequence control can be monitored by the monitor device 11, and the monitor device 11
2 can be given a control command. Moreover,
When a control command having a lower priority than the control command currently executed by the PC 12 is specified in the monitor device 11, the control command is not output to the PC 12, so that the PC 12
12 can be prevented beforehand. Also, P
Only when the operation condition of the control instruction having a higher priority than the control instruction currently being executed in C12 is satisfied, the display content on the display screen 24 is changed, so that the operation state of the PC 12 can be accurately displayed. According to the present invention, it is possible to instruct the PC executing the sequence control only the control instruction having a higher priority than the control instruction being executed by the PC from the monitor device. At the same time, the operating state of the PC can be accurately displayed, and a monitoring device suitable for a control system for remotely monitoring the PC can be provided.

BRIEF DESCRIPTION OF THE 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 an operation condition of a control command in a PC monitored by the monitor device. FIG. 3 is a diagram showing a display screen at the time of 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. [Description of Signs] 2-Program memory 3-Work memory 4-CRT 11-Monitor device 12-PC 21-Display screen 22-Progress status column 24-Operation command key

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-64-15810 (JP, A) JP-A-62-17842 (JP, A) JP-A-64-53237 (JP, A) 242708 (JP, A) JP-A-6-95710 (JP, A) JP-A-57-76606 (JP, A) JP-A-4-242805 (JP, A) (58) Fields investigated (Int. ^7, DB name) G05B 19/048 G05B 19/05 G05B 23/02 301

Claims (1)

(57) [Claim 1] Connected to a programmable controller that executes sequence control of a control device based on a sequence control program configured by a plurality of operation steps,
In a monitor device for monitoring the operation state of a programmable controller, control instruction means for receiving an instruction input of a control instruction in a sequence control program, priority of the control instruction input from the control instruction means, and control operation being executed by the programmable controller And the priority of the control instruction instructed from the control instruction means is higher than the priority of the control operation being executed by the programmable controller in the comparison result of the priority comparison means. In this case, the control command input from the control command means is output to the programmable controller and
When the priority is lower, an instruction is input from the control instruction means.
Output to the programmable controller.
And a control command output means.