JPH11167409A - Programmable controller running on parallel execution language - Google Patents

Abstract

(57) [Summary] [PROBLEMS] For a program described in a conventional sequential function chart (SFC), the language to be described is graphic, input is complicated, it is difficult to change or delete the program, and the user is not familiar with the language. The programmer
It takes time to edit the program. A programmable controller having an input unit for receiving a signal, an output unit for outputting a signal, a data memory unit, a program memory unit for storing a control program, and an operation unit for performing an operation according to the control program stored in the program memory unit. , A parallel execution language having a text-type instruction representing parallel execution and inputting a program using the instruction, wherein an arbitrary number of parallel operations are described in a text type, or one operation is selected from a plurality of operations. The SFC in which the selection operation to be selected and executed is described in a text type, and the parallel operation and the selection operation are described in a graphic type, and the program described in the text type can be mutually converted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an apparatus for inputting a user program such as a programmable controller using a programming apparatus or the like.

[0002]

2. Description of the Related Art The basic configuration of a programmable controller referred to here is, as shown in a block diagram of a circuit configuration in FIG. 7, a program memory 75a [stores a program in which a control procedure is described in a dedicated language] and a data memory 75b. A memory unit 75 comprising [storage of the operation results in the operation unit]; and an operation unit called a central processing unit 71 (CPU) [a program counter indicating a program number, a register for storing instructions, a decoder for decoding instructions, an operation Arithmetic / Logical Arithmetic Unit (ALU) for performing various operations in accordance with instructions of a logic unit and a program for controlling the timing of the operation, and signal inputs 77 of various detection devices provided in the machine and operation devices provided in the control device. Input unit 72 [so-called input interface], which is a part to be operated, and an indicator light provided on an actuator or operation unit provided on the machine. Output driving power signal
The output unit 73 (so-called output interface), which is a part that performs the operation 78, is connected to the outside of the programmable controller having functions of creating a program, writing to a program memory, reading from a program memory, and reading control data from a data memory (monitor). Peripherals 76
And a power supply unit 74 [generally generating a control voltage 79b as an active power supply for a control element required inside the programmable controller from a general commercial power supply 79a] for generating a necessary direct current inside the programmable controller.

Conventionally, as a language for describing parallel operations, a sequential function chart [hereinafter, referred to as a sequential function chart,
Abbreviated as "SFC"]. The SFC expresses the execution order and processing contents in the sequence control in several types of description elements [for example, see "Sequence Control Engineering", pages 124 to 152, published by Ohmsha on November 21, 1988, edited by the Institute of Electrical Engineers of Japan). FIG. 8 shows a conventional example thereof, where S0, S1,.
The one represented by 7 is called a step. These steps represent a unit of a sequence executed when a given condition is satisfied in the order control.

[0004] Usually, a step is accompanied by zero or more actions, which are executed when the step is in an execution state. Each step is connected by a directional branch called a link, and a transition line indicating a condition for transition of the execution state from the former step to the latter step is written on a horizontal line written directly on the link.

The transition condition is a logical condition for moving to the next step, which is indicated by T0, T1,..., T7 in FIG. When the preceding step is connected to a plurality of sets of transition conditions and steps as in step S0 in FIG. 8 [usually connected to the next transition condition and a single horizontal line]
Represents the start of the selection operation, and proceeds to the next step in which the transition condition is satisfied. If a plurality of transition conditions are satisfied, the left side has priority. In the case of step S0 in the case of FIG. 8, if the transition condition T0 is satisfied, the process proceeds to step S1,
The action associated with step S1 is executed. If the transition condition T2 is satisfied, the process moves to step S2, and executes an action associated with step S2. Transition condition T0,
When both T2 are satisfied, the transition condition T0 is prioritized, and the process shifts to step S1 to execute an action associated with step S1.

If both the transition conditions T0 and T2 are not satisfied, the execution step stagnates at step S0,
Perform the action associated with 0. Step S in FIG.
When a plurality of preceding transition conditions and the next step are connected by a single horizontal line as in 7, this indicates the end of the selection operation, and is connected to the step shifted to the start of the selection operation. When the transition condition is satisfied, the process proceeds to the next step. In the case of step S7 in FIG. 8, when the start of the selection execution is S1, step S7 is executed when the transition condition T1 is satisfied, and when the start of the selection execution is step S2, the transition condition T6 is satisfied. Sometimes step S7 is executed.

In FIG. 8, when there is only one transition condition to the next step as in step S2 and there are a plurality of next steps, and the two steps are connected by a double horizontal line, a parallel connection is established. Indicates the beginning of the operation. In the case of FIG. 8, if the transition condition T3 is satisfied, steps S3 and S4 are all executed. In FIG. 8, the preceding plural steps and the next step are connected by a double horizontal line as in step S6, and if there is only one transition condition between the double horizontal line and the next step, the parallel operation is performed. When all of the preceding steps are in the execution state and the transition condition is satisfied, the process proceeds to the next step. FIG.
In the case of step S6, steps S3 and S5
Is in the execution state and the transition condition T5 is satisfied, the process proceeds to step S
6 is executed.

[0008]

However, such a program described in SFC in the prior art expresses a sequence operation with respect to a control target by satisfying a transition condition between steps. On the other hand, on the other hand, since the language to be described is graphic, the program input from the program input device is complicated, and it is not easy for the maintenance personnel on the site to change or delete the program.

[0009] Further, for a general programmer who is unfamiliar with the language, it takes several to ten and several times longer to edit the program than when editing in a text type language. Therefore, S
Programs written in FC are not widely used, even though the structure and flow of the programs are easy to understand. Therefore, the present invention provides a text-based language that can easily describe parallel execution operations and selective execution operations, and a language system that can mutually convert programs written in this text-type language and programs written in SFC. The purpose is to provide.

[0010]

In order to solve the above-mentioned problems, the present invention provides an input unit for taking in an external signal, an output unit for outputting a signal to the outside, a data memory unit, In a programmable controller having a program memory unit storing a control program and an operation unit operating in accordance with the control program stored in the program memory unit, a text-type instruction representing parallel execution is used, and A programmable controller that operates in a parallel execution language, comprising a program input unit.

According to a second aspect of the present invention, there is provided a means for describing, in text form, an arbitrary number of parallel operations or a selection operation for selecting and executing one operation from a plurality of operations. A programmable controller that operates on the parallel execution language according to claim 1.

According to a third aspect of the present invention, there is provided a system comprising means for mutually converting a sequential function chart describing a parallel operation or a selection operation in a graphic type and a program described in the text type. Alternatively, a programmable controller that operates on the parallel execution language according to claim 2.

As described above, according to the present invention, several types of text-type instructions for describing parallel execution and selective execution are prepared, and the parallel execution and selective execution can be easily performed by the above-mentioned means which defines rules for describing the instructions. In addition, it is possible to explicitly describe, it is possible to reduce the time for compiling a program, and it is possible to convert a program described in the text type language and a program described in SFC into and out of each other. It has a special effect.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. In all the drawings, the same reference numerals are the same or equivalent members. FIG. 1 is a diagram showing examples of instructions and symbols, which are elements of a text type language that describes parallel execution and selective execution according to an embodiment of the present invention.
In FIG. 1, a transition execution instruction "transition condition [TRAN COND-ITION]" describes a conditional expression after leaving one or more blanks as a delimiter, and is concluded with ";" which is an end symbol of the instruction. .

If the conditional expression is satisfied, the process proceeds to the next step. If the conditional expression is not satisfied, the process stays at the previous step. The parallel execution operation includes a “parallel [PARALELL]” instruction indicating the start of parallel execution, a “connect” instruction indicating connection to an end point of parallel execution, and an “end parallel [END] indicating termination of parallel execution. PARALEL
L] is described using the "instruction. The" parallel "instruction is
After one or more blanks are placed as delimiters, the names of all steps to be executed in parallel are sequentially described, and are concluded with ";" which is an instruction end signal.

The step names are also separated by one or more blanks. The "connect" instruction is written with a label attached to the "end parallel" instruction that indicates the end of parallel execution after leaving one or more blanks as delimiters, and concluded with ";" which is the instruction end signal. It is. "
The end parallel "instruction" has one or more blanks as delimiters, then sequentially describes all preceding step names, and is concluded with ";" which is an instruction end signal.
Step names are also separated by one or more spaces.

"SELECT [SELE" indicating the start of selection execution
The description is made using a “CT]” instruction, a “Connect [CONNECT]” instruction indicating the connection to the end point of the selection execution, and an “END SELECT” instruction indicating the end of the selection execution. In the [SELECT] instruction, after placing one or more blanks as delimiters, sequentially describe the labels attached to all the transition execution instructions “transition conditions” to be selected and executed. There is a closing ";".

Labels are also separated by one or more blanks. The "connect" command is followed by one or more blanks as delimiters, followed by the label attached to the "end select" command that indicates the end of the selection execution, and concluded with the ";" It is. The "end select" instruction is a sequence of all preceding transition execution instructions "transitions" after one or more spaces as delimiters.
The labels attached to the "conditions" are sequentially described and concluded with ";", which is the end signal of the instruction. The "connect" instruction indicating the connection to the end point of the parallel execution and the The “connect” command indicating the connection may be the same command or a different command.

FIG. 2 shows a program written in SFC as shown in FIG. 8 in which the numbers are assigned to the respective description elements of SFC. The numbers 1, 4, 7, 10, 11, 13, 16, 16,
Reference numeral 19 denotes an element for describing a step, and numbers 2, 9, 14, and
Reference numeral 18 denotes an element for describing a link, and numbers 3, 5, 6, 8, and
Elements 12, 15, 17, and 20 are elements for describing transition conditions.

FIG. 3 shows a programming example when a program described in SFC as shown in FIG. 2 is described in the text type language. FIG. 4 is a diagram showing the relationship between the numbers of the description elements allocated in FIG. 2 and the line numbers of the program in FIG. As shown in FIG. 4, a program written in SFC and a program written in the text type language can be easily associated with each other, and can be mutually converted.

Next, how the present invention can easily cope with a change in a program will be described below. FIG. 5 can be easily dealt with in FIG. 6 if an additional change occurs in a portion enclosed by a dotted rectangle in the program described in the SFC of FIG. By comparing FIGS. 2 and 3 with FIGS. 5 and 6, it is considered that the usefulness of the present invention is obvious.

[0022]

As described above, according to the present invention, in a programmable controller, a general programmer and a maintenance person can easily execute parallel execution and parallel execution of several types of text type instructions and simple rules for describing the instructions. Since the selection execution can be described, the program editing time can be greatly reduced, and the operability of the apparatus can be improved. On the other hand, at the time of debugging, by displaying a program described in SFC in which the structure and flow of the program are easy to understand, the sequence can be visually grasped, so that the debugging time can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of an instruction and a symbol as elements of a text type language that describes parallel execution and selective execution according to an embodiment of the present invention.

FIG. 2 is a diagram in which a program written in SFC according to an embodiment of the present invention is assigned a number for each SFC description element;

FIG. 3 is an example of programming when a program described in SFC in FIG. 2 is described in a text type language according to an embodiment of the present invention;

4 is a diagram showing the relationship between the numbers of the description elements allocated in FIG. 2 and the line numbers of the program in FIG. 3 according to an embodiment of the present invention;

FIG. 5 is a diagram in which a number is assigned to each description element of the SFC when a part of the program described in the SFC in FIG. 2 is additionally changed;

FIG. 6 is a diagram showing the relationship between the numbers of the description elements allocated in FIG. 5 and the line numbers of the program created according to FIG. 3;

FIG. 7 is a block diagram showing a circuit configuration including peripheral devices of a programmable controller.

FIG. 8 is an explanatory diagram in the related art.

[Explanation of symbols]

 71 Operation unit (CPU) 72 Input unit 73 Output unit 74 Power supply unit 75 Memory unit 75a Program memory 75b Data memory 76 Peripheral device 77 Input 78 Output 79a Commercial power supply 79b Control voltage

Claims (3)

[Claims] An input unit for receiving an external signal;
In a programmable controller having an output unit for outputting a signal to the outside, a data memory unit, a program memory unit storing a control program, and an operation unit operating according to the control program stored in the program memory unit, A programmable controller operating in a parallel execution language, comprising: a text-type instruction representing execution; and means for inputting a program using the instruction. 2. The apparatus according to claim 1, further comprising means for describing an arbitrary number of parallel operations or a selection operation for selecting and executing one operation from a plurality of operations in a text type. A programmable controller that operates in a parallel execution language. 3. The apparatus according to claim 1, further comprising means for mutually converting a sequential function chart describing a parallel operation or a selection operation in a graphic type and a program described in the text type. Programmable controller that operates in a parallel execution language.