JP3114907B2 - How to change the sequence program of the programmable controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for changing a sequence program of a programmable controller for changing a sequence program executed by the programmable controller during operation of the programmable controller.

[0002]

2. Description of the Related Art Conventionally, it has been known that a programmable controller executes a sequence program to automatically control an electronic device. The sequence program is created by a programming device connected to the programmable controller. In addition, the sequence program can be modified even during operation of the programmable controller. Since the sequence program is stored in the user program memory in the programmable controller, the sequence program is sent to the programming device when modifying the sequence instruction in the program. The user displays the sequence program on the programming device and modifies the sequence instructions in the sequence program. Thereafter, a grammar check for all program instructions in the sequence program is performed on the programming device in response to a grammar check instruction from the user. This grammatical check is to perform some checks such as whether the sequence instruction is described in a correct format, and depending on the program instruction, whether the sequence instruction has a correct connection relationship with an adjacent program instruction. After the grammar check, the modified sequence program is sent to the programmable controller. The programmable controller has realized the change of the sequence program by exchanging the sequence program in the user program memory with the reception sequence program.

[0003]

According to the conventional method, even when only one sequence instruction is changed, the entire sequence program is stored in a programmable controller.
It must be transferred to and from the programming device.
The grammar check of the sequence instruction is also performed for the entire sequence program, and the sequence instruction that has not been changed must also be checked. Therefore, it takes time to change the sequence program. Particularly, when the sequence program is changed during the operation of the programmable controller, it is often urgent, and it is desired by the user to reduce the time required for changing the sequence program.

In view of the above, an object of the present invention is to provide a method of changing a sequence program of a programmable controller, which can reduce the time required to change the sequence program.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, a sequence program executed by a programmable controller is transferred from the programmable controller to a programming device. In the method of changing the sequence program of the programmable controller to modify the transferred sequence program, except during the operation of the programmable controller, permit use of all sequence instructions for modifying the sequence program on the programming device, During the operation of the programmable controller, the types of sequence commands usable for the correction are limited.

[0006]

[0007]

According to the first aspect of the present invention, the number of grammatical checks is reduced by limiting the sequence commands used for correction.
Thus, the processing time of the grammar check is reduced.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Before describing the present invention, a programmable controller and a programming device will be described. FIG. 2 shows a circuit configuration of a portion related to the present invention of the programmable controller. FIG. 3 shows a circuit configuration of the programming device.

In FIG. 2, a central processing unit (CP)
U) 10 controls the entire apparatus according to a system program in a system memory 11. The CPU 10 automatically controls the electronic device according to the sequence program in the user program memory 12 during the system operation. The sequence program is transferred from the programming device via the interface (I / O) 13 and written into the user program memory 12 by the CPU 10. However, in the case of a change of the program instruction according to the present invention, only the correction content constituted by the correction portion and its position is instructed from the programming device, and the CPU 10 writes only the correction portion.

In FIG. 3, a central processing unit (CP)
U) 20 creates and edits a sequence program according to the system program in the system memory 21. In the system memory 21, in addition to the above system program, a program area for storing a program according to the present invention and a work area for storing input / output information for the CPU 20 are provided. Keyboard 2 in work area
The program command to be changed and the like input from 4 are temporarily stored.

A sequence program is created and edited on the user program memory 22. Keyboard 24
, An operation instruction to the CPU 20 and program editing contents are input. The sequence program being created or edited is displayed on the display 25. The created and modified sequence program is transferred to the programmable controller via the I / O 23.

In this embodiment, as a first feature, the sequence commands that can be changed during the operation of the programmable controller are limited, and the amount of modification of the sequence program is reduced.

Hereinafter, the correction process will be described. FIG. 1 shows the contents of the sequence program change processing executed on the programming device side. When the correction mode of the sequence program is input by the keyboard 24, the CPU 20 executes the control procedure of FIG.
And execute it. When the CPU 20 detects that the system (programmable controller) is currently in operation by referring to the operation mode flag that is turned on when the system is started, the process proceeds to S20 and subsequent steps, which will be described later, according to the present invention. On the other hand, when the system is not operating, a correction process for enabling all sequence commands as in the past is performed (S150).

When the system is in operation, first, a sequence program to be corrected is transferred from the programmable controller to the programming device according to the same processing procedure as before, and is read into the user program memory 22 of the programming device (S20). The CPU 20 displays this sequence program on the display 25 in the form of the sequence circuit diagram A in FIG. The user looks at this display and instructs the correction position of the sequence command using the keyboard 24, and inputs the sequence command to be corrected. The CPU 20 displays the correction sequence command input at the display position corresponding to the instructed position (see the changed program in FIG. 5-
S30).

The CPU 20 determines whether the input correction sequence command is a command of a type predetermined as use permission. More specifically, it is configured in one step such as a contact instruction and a coil (output) instruction, and permits use of an instruction that is not related to other sequence instructions. When the contact command is changed as shown in FIG. 5, the CPU 20 detects that the contact command is changed from the format of the input command (S40). Next, the CPU 20 identifies the correction content of the sequence command (S100). For this purpose, the CPU 20 compares a sequence command before correction on the user program memory 22 with a sequence command for input correction on the basis of the correction position designated by the user, and detects a mismatched portion. This inconsistency is a correction. This corrected part is the instruction code part in the sequence instruction (FIG. 5).
In the example of (1), it is determined that the instruction type has been changed. Further, when the correction portion is the operand portion (corresponding to the contact name in FIG. 7 or the set value of the timer command in FIG. 9) in the sequence command, it is determined that the parameter has been changed.

The CPU 20 creates a correction command (correction content of the present invention) to be transmitted to the programmable controller based on the above determination result (S110). The correction instruction is, for example, an instruction code indicating that it is an instruction relating to correction of a sequence instruction, a correction position of the sequence instruction on the sequence program, the type of correction (indicating whether the instruction code is to be changed or the operand is to be changed), and the correction instruction Consists of sequence instructions. The created correction instruction is I /
The data is transmitted to the programmable controller via O23 (S120).

This correction command is transferred to the CPU 10 via the I / O 13 of the programmable controller. When the CPU 10 of the programmable controller detects the input of the correction command by the command analysis, it sequentially executes the control procedures of FIGS. 4, 6, and 8 to identify the content of the correction command, and follows the content specified by the correction command. Execute the correction of the sequence instruction. See Figure 4 for the change of contact instruction code.
The change is detected by the control procedure (S20).
0). The CPU 10 reads out the sequence instruction to be corrected included in the correction instruction, and checks the syntax of the instruction code and the format of the operand part (S
210 to S240). If there is no error in the format, the correction position specified in the correction instruction is converted into an address of the user program memory 12, and a sequence instruction to be corrected is written to this address (S250 → S
260). As a result, the currently executed sequence program is changed in the programmable controller.

The change of the operand of the sequence instruction and the change of the set value are performed by the control procedures of FIGS. 6 and 8, respectively. These procedures are the procedures for writing in the user program memory 12 after the grammar check in the same manner as described above, and a detailed description thereof will be omitted. As explained above,
In the present embodiment, a sequence instruction that can be changed is
Since the instruction is not related to the Kens instruction, the target of the grammar check is only the sequence instruction to be corrected, and the time required for the grammar check is reduced as compared with the related art. Further, the user only needs to partially modify the sequence program on the programming device, and does not need to perform an instruction operation on the programmable controller.

The following example can be implemented in addition to the present embodiment.

1) In this embodiment, the grammatical check is performed on the programmable controller side in consideration of noise contamination when transferring the correction instruction, but it may be performed on the programming device side. In this case, the grammar check may be performed each time a correction sequence command is input, or the correction sequence command may be performed collectively. At this time, the grammatical check is not performed on the programmable controller side, and only the writing process of the correction sequence instruction is performed.

2) In the present embodiment, only the sequence command to be corrected is transmitted to the programmable controller. However, after the sequence program that can be corrected is limited and the sequence program is corrected, the correction is performed as in the conventional case. It is also possible to transmit the entire sequence program already completed. In this case, it goes without saying that the grammar check is performed on the programming device side, and the check target is only a limited sequence instruction. For this purpose, a grammar check program in which sequence commands are limited and a grammar check program in which sequence commands are not limited are prepared, and the grammar check program is switched between the system operation and the system initialization stage before the system operation. .

3) In this embodiment, when an unusable sequence instruction is used for correcting a sequence instruction, a message indicating that the sequence instruction cannot be used is displayed (S60 in FIG. 1). At this time, the type of the usable sequence instruction may be displayed as a guide.

[0024]

As described above, according to the present invention, the time required for changing the sequence program can be shortened as compared with the related art, so that the effect of improving the performance of the programmable controller can be obtained.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a procedure of changing a sequence program on a programming device side according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a circuit configuration of a programmable controller according to an embodiment of the present invention.

FIG. 3 is a block diagram illustrating a circuit configuration of a programming device according to an embodiment of the present invention.

FIG. 4 is a flowchart showing a procedure for changing a sequence program on the programmable controller side according to the embodiment of the present invention;

FIG. 5 is an explanatory diagram showing an example of changing a sequence program.

FIG. 6 is a flowchart showing a procedure of changing a sequence program on the programmable controller side according to the embodiment of the present invention.

FIG. 7 is an explanatory diagram showing another example of changing a sequence program.

FIG. 8 is a flowchart showing a procedure for changing a sequence program on the programmable controller side according to the embodiment of the present invention.

FIG. 9 is an explanatory diagram showing still another example of the change of the sequence program.

[Explanation of symbols]

 10, 20 CPU 11, 21 System memory 12, 22 User program memory 13, 23 I / O 24 Keyboard 25 Display

Claims (1)

(57) [Claims] 1. A method of changing a sequence program of a programmable controller which transfers a sequence program to be executed by a programmable controller from the programmable controller to a programming device and corrects the transferred sequence program on the programming device. Except during operation of the controller, use of all sequence instructions for modification of the sequence program on the programming device is permitted, and during operation of the programmable controller, types of sequence instructions that can be used for the modification are limited. A method for changing a sequence program of a programmable controller, characterized in that: