JPH10247107A - Shortening method for sequence processing time - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the sequence processing time via the switching of program steps, the omission of unnecessary operations, etc., by switching the operating sequence of contacts to operate earlier a contact whose on/off operations are indispensable than others or operating only the contact to change a program. SOLUTION: A program is preparatorily executed and the information on a circuit and the contacts are stored in a contact forming sequence storage area 2d of a memory 2. At the same time, the addresses which store the circuit elements in the area 2d are stored in a circuit head address storage area 2c. Then a contact whose on/off operations are indispensable to operate the coil included in every circuit element is selected out of those contacts stored in the area 2d. In order to operate the selected contact with preference, the program is rewritten and stored in a sequence changed program area 2b. Finally, the program stored in the area 2b is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a processing method in sequence control by a programmable controller or the like.

[0002]

2. Description of the Related Art In various fields such as a machine industry, a chemical plant, and a household electric appliance, processing by sequence control for performing control according to a predetermined procedure is performed.

In the conventional sequence processing, an operator creates a program to be executed by a central processing unit of a controller based on a circuit described by a ladder diagram, and when executing the program, a contact included in the circuit is created. , All the instructions corresponding to the operation of the coil and the like are executed in the operation order.

[0004] However, with the sophistication and complexity of systems to be controlled, there is a demand for faster processing by sequence control, that is, shorter processing time.

As a method of shortening the processing time of the sequence control, for example, there are methods described in JP-A-62-111303 and JP-A-4-218806.

[0006] The invention described in Japanese Patent Application Laid-Open No. 62-111303 discloses an input start condition,
The program is divided into intermediate start conditions, output definitions, and the like, and the execution of the program is performed from the output side. If the condition is determined and the condition is not satisfied, the next output instruction is executed to execute unnecessary programs. To avoid, while
The invention described in Japanese Patent Application Laid-Open No. 4-218806 provides a means for determining whether to execute or not execute one instruction in a program according to the operation result up to the immediately preceding step, and omit unnecessary operations. By doing so, the processing time is reduced.

However, even when the control program is executed by using the processing method disclosed in the above invention, at the time of execution, the instruction is executed for each step in accordance with the operation order of the contacts, coils and the like included in the circuit. In addition, since the condition is determined for each step at the time of execution, there is a problem that the calculation time per circuit becomes long.

[0008]

SUMMARY OF THE INVENTION The present invention provides a sequence processing for sequentially controlling a circuit having at least one circuit element including at least one contact point and one output coil by a predetermined program. The present invention relates to a method for reducing the sequence processing time which has solved the above-mentioned problems.

According to the first and second aspects of the present invention, a time-consuming process such as executing a program one step at a time in accordance with the operation sequence of contacts, coils and the like included in a circuit, and performing condition determination at each step is performed. Without changing the program steps, or by omitting unnecessary operations in the program, the sequence processing time can be shortened.

[0010]

According to the method of shortening the sequence processing time according to the present invention, a program is pre-executed and contacts included in the circuit to be controlled are stored in a memory of a central processing unit in the order of operation in the circuit. Of the contacts stored and stored in the memory, the contacts for which ON / OFF operation is indispensable for the operation of the output coil included in the circuit are read out from the memory, and the contacts are operated such that the contacts are operated first. The program is changed by changing the operation order or operating only the contact. As a result, it is only necessary to prioritize the contacts that must be turned on or off for the operation of the output coil, or to operate only those contacts, and unnecessary processing is not performed. Processing time until output is reduced. Therefore, it is possible to shorten the time of the sequence processing.

Further, in the method for reducing the sequence processing time according to the present invention, the probability that the output coil included in the circuit element is turned off by turning off the contacts for all the contacts included in the circuit element (hereinafter referred to as “probability”) "Impact degree"), and changing the program by exchanging the operation order of all the contacts included in the circuit element so that the contact having the greater impact value operates first. Features. Thereby, the necessity of the contact included in the circuit element for the operation of the output coil included in the circuit element can be evaluated by a specific numerical value, and therefore, the program can be changed more effectively.
As a result, the time of the sequence processing can be reduced, and highly efficient processing can be performed.

[0012]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram of a control device for performing a sequence process according to the present invention. This device is a CP
A program includes a U (central processing unit) 1, a memory 2, a stack 3, a comparison operation unit 4, an input unit 5, and an output unit 6, and a program is stored in the memory 2. In the memory 2, as will be described later, a program area 2a, a sequence-changed program area 2b, a circuit head address storage area 2c, and a contact establishment order storage area 2d are set.

FIG. 2 is a flowchart showing the sequence of the sequence processing using the method according to the present invention. Hereinafter, the processing procedure will be described with reference to FIG. First, step 11
Then, the sequence processing program is loaded into the program area 2a (see FIG. 1) in the memory 2. Next step
In step 12, information on the circuit to be processed and the contacts included in the circuit, that is, the structure of the circuit and the circuit elements constituting the circuit (the number of AND circuits and OR circuits, etc.) and the state of each contact are obtained. Next, in step 13, the program is preliminarily executed. In step 14, information on the circuit and the contacts is stored in the contact formation order storage area 2d in the memory 2, and each circuit element is stored in the contact formation order storage area 2d. The stored address is stored in the circuit head address storage area 2c. Further, in step 15, from among the contacts stored in the contact formation order storage area 2d, a contact whose ON or OFF operation is indispensable for operating a coil in each circuit element is selected, and this contact is operated with priority. Program is rewritten (contact order is changed), and the rewritten program is stored in the reordered program area 2b. Finally, in step 16, the program stored in the reordered program area 2b is executed.

FIG. 3 is a flowchart showing a processing procedure of a circuit in which the order of contacts is changed by using the method according to the present invention. Here, a circuit to be processed includes a contact included in one circuit and a plurality of contacts. The branch including the output coil and the output coil form a series, that is, an AND circuit. First, in step 21, the circuit program is read from the reordered program area 2b (see FIG. 1) of the memory, and in step 22, the top contact is evaluated, that is, the ON / OFF state is checked. Next, if this contact is established in step 23, that is, if it is turned on, the next contact is evaluated in the following step 24. Further, in step 25, it is determined whether or not this contact is the last contact in the circuit, and if it is the last contact, it is checked in step 26 whether or not the contact is established. The coil is turned on, and if not, the output coil is turned off in step 28. If not the last touch point,
Returning to step 23, steps 23 to 25 are repeated until the last contact point is reached. If the first contact is not established, the output coil is immediately turned off in step 28. Finally, after the output coil is turned on or off, the register of the CPU 1 and the stack 3 (see FIG. 1) are cleared in step 29, and the process jumps to the next circuit in step 30.

FIG. 4 is also a flowchart showing a processing procedure of a circuit whose contact order has been changed by using the method according to the present invention. Here, a circuit to be processed includes a contact included in one circuit and a plurality of contacts. The included branches are parallel, that is, form an OR circuit. First, in step 31, the circuit program is stored in the program area 2b of the memory whose order has been changed (see FIG. 1).
In step 32, the first contact is evaluated, that is, the ON / OFF state is checked. Next, if this contact is established in step 33, that is, if the contact is turned on, the output coil of the circuit is turned on in the subsequent step 34. Here, the contact is not established,
That is, if it is OFF, the next contact is evaluated in step 35. Further, in step 36, it is determined whether or not this contact is the last contact in the circuit, and if it is the last contact, it is checked whether or not it is established in the following step 37, and if not, the output is made in step 38. The coil is turned off, and if it is established, the output coil is turned on in step. If it is not the last contact, the process returns to step 33 again, and steps 35 to 36 are repeated until the last contact is reached. Finally, after the output coil is turned ON or OFF, the register of the CPU 1 and the stack 3 (see FIG. 1) are cleared in a step 39.
Jump to the next circuit with 40.

FIG. 5 shows an example of a program change procedure using the method according to the present invention. In the circuit shown in the ladder diagram on the left side of (a) of the figure and consisting of the contacts X1 to X4 and the coil Y1, consider the case where the coil Y1 is turned on. At this time, the processing flowchart is as shown on the right side of the figure. Here, the contacts X1 to X3 are always OFF and the contact X4
Is always ON. Therefore, in order to turn on the coil Y1, it is essential to turn on the contacts X1 to X3. Here, as shown in (a), in the contacts X1 to X3, X1 and X2 form a series, that is, an AND circuit, and the contacts X3 form an OR circuit. Therefore, to turn on coil Y1, turn on contacts X1 and X2 together or turn on contact X3.
Or any one of the following. In this case, if the above-mentioned, that is, the contact X3 is turned on, only one command is required. Therefore, the first circuit is shown in Fig.
Then, the initial program can be rewritten in accordance with the format shown in FIG. Therefore, the procedure of the program is as shown in the flowchart on the right side of FIG.

FIG. 6 is a flow chart showing a method according to the present invention, in particular, a procedure of a sequence process using a contact exchange based on the value of the contact and the degree of influence of the contact. Hereinafter, the processing procedure will be described with reference to FIG. First, in step 41, a sequence processing program is loaded into the program area 2a (see FIG. 1) in the memory 2. Next, in step 42, information on the circuit to be processed and the contacts included in this circuit, that is, the structure of the circuit and the circuit elements constituting the circuit (the number of AND circuits and OR circuits, etc.) and the state of each contact, etc. Get. After that, in step 43, the degree of influence of all the contacts included in the circuit is calculated. Next, in step 44, the program is preliminarily executed, and in step 45
Then, the information on the circuit and the contacts is stored in the contact formation order storage area 2d in the memory 2, and the address where each circuit element is stored in the contact formation order storage area 2d is stored in the circuit head address storage area 2c. Remember. Further, in step 46, from among the contacts stored in the contact formation order storage area 2d, a contact whose influence degree obtained in step 43 is larger than other contacts is selected, and this contact is operated with priority. Program is rewritten (contact order is changed), and the rewritten program is stored in the reordered program area 2b. Finally, in step 47, the program stored in the reordered program area 2b is executed.

FIG. 7 is a flowchart showing a procedure for obtaining the degree of influence of the contact point on the coil in the present invention. Here, the degree of influence is the probability that in a circuit consisting of a coil and one or more contacts as described above, when any one contact is turned off when all contacts are on, the coil will be turned off. It is represented. The procedure for determining the degree of influence is as follows. First, in step 51, the number of branches (portions forming an OR circuit) included in one circuit is obtained, and then in step 52, the degree of influence is obtained for all the contacts included in the circuit. Then, in step 53, it is checked whether or not any one branch has two or more contacts. If there are two or more contacts, in step 54, the influences of all the contacts included in the branch are equal. Value. Further, in step 55, it is determined whether or not the calculation of the degree of influence has been performed for all the contacts included in the circuit, and the above processing is repeated until the calculation is performed for all the contacts.

FIG. 8 shows an example of a program change procedure using the above-mentioned degree of influence. In the circuit shown in the ladder diagram on the left side of (a) of the figure and consisting of the contacts X1 to X4 and the coil Y1, consider the case where the coil Y1 is turned on. At this time, the processing flowchart is as shown on the right side of the figure. Here, the contacts X1 to X4 are always OFF. Therefore,
In order to turn on the coil Y1, it is essential to turn on the contacts X1 to X4. First, the degree of influence is determined for the contacts X1 to X4. Here, the value is shown by multiplying the degree of influence by 100. As a result, the degree of influence of each contact becomes the value shown in (b) of the figure. Therefore, among the contacts X1 to X4, the contact having the highest influence is X4, and therefore, as shown in FIG.
Rewrite the program to turn it on. As a result, the first circuit is equivalent to the circuit as shown in FIG. Further, as shown in (c), the contacts X1 to X3 are formed by connecting X1 and X2 in series, that is, forming an AND circuit, and this and the contact X3 are ORed.
Forming a circuit. Therefore, to turn on coil Y1, turn on both contacts X1 and X2 or turn on contact X3.
It is only necessary to select either ON or ON. In this case, if the above-mentioned, that is, the contact X3 is turned on, only one command is required. Therefore, the first circuit
It is sufficient to replace the circuit as shown in (d) so as to be equivalent, and to rewrite the initial program accordingly. Accordingly, the processing procedure is as shown in the flowchart on the right side of FIG.

[0021]

As described above, according to the method of the present invention, the processing is performed by excluding, from the contacts included in one circuit, the contacts not necessarily required for the operation of the output coil. Therefore, the processing time until output in one circuit is shortened. Therefore, it is possible to reduce the time for the sequence processing and perform highly efficient processing.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control device for performing a sequence process according to the present invention.

FIG. 2 is a flowchart showing the sequence of a sequence process using the method according to the present invention.

FIG. 3 is a flowchart showing a processing procedure of an AND circuit in which the order of contacts is changed using the method according to the present invention.

FIG. 4 is a flowchart illustrating a processing procedure of an OR circuit in which the order of contacts is changed using the method according to the present invention.

FIG. 5 shows an example of a circuit program changing procedure using the method according to the present invention.

FIG. 6 is a flowchart illustrating a sequence of a sequence process including calculation of the degree of influence of a contact point using the method according to the present invention.

FIG. 7 is a flowchart illustrating a procedure for calculating the degree of influence of a contact point.

FIG. 8 shows an example of a circuit program change procedure using the influence of a contact point according to the method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CPU 2 Memory 3 Stack area 4 Comparison operation part 5 Input part 6 Output part

Claims (2)

[Claims] In a sequence processing for sequentially controlling a circuit including at least one circuit element including at least one contact point and one output coil by a predetermined program, the program is pre-executed. The contacts included in the circuit element to be controlled are stored in the memory of the central processing unit in the order of operation in the circuit element, and among the contacts stored in the memory, the operation of the output coil included in the circuit element is determined. For this reason, the on / off operation is indispensable to read the contacts from the memory, and to change the operation order of all the contacts included in the circuit element so as to operate the contacts first, or to operate only the contacts, A method for shortening a sequence processing time, characterized in that the program is changed. 2. The method according to claim 1, wherein, for all the contacts included in the circuit element, a probability that the output coil included in the circuit element is turned off by turning off the contact is determined. A method for shortening the sequence processing time, characterized in that the program is changed by changing the operation order of all the contacts included in the circuit element so that the contact having the larger value is operated first.