JPH1027010A - System for processing run/stop input signal of programmable controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To synthesize a plurality of signals so as an operator of a programmable controller(PLC) not to be confused by providing a plurality of RUM/STOP inputs in accordance with the object for performing FUN/STOP operation of the PLC. SOLUTION: The RUN or STOP operation of a PLC 19 is decided by giving priority to a signal which changes afterward by detecting the rising and falling edges of signals made valid with parameters against RUN/STOP signals, etc., from a RUN/STOP input terminal 1, a RUN/STOP switch 4 incorporated in the PCL 19, and programming tool 8. Therefore, smooth RUN/STOP operation can be performed by selectively using many standard RUN/STOP inputs provided as a standard.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for controlling a large number of ON / O
For a programmable controller that generates a number of ON / OFF outputs by programmable electronic means in response to the FF input signal, a RUN input signal as an execution command for the sequence program and an S as an execution stop command for the programmable controller.
The present invention relates to an improvement in an input signal processing method for a TOP input signal, and more particularly to a signal processing method for avoiding operator confusion with respect to a plurality of RUN / STOP input signals.

[0002]

2. Description of the Related Art FIG. 9 is a block diagram showing an entire configuration of a generally used programmable controller (hereinafter referred to as a PLC).

In FIG. 9, 1 is an input interface 2
, Which is a switch connected to the RUN detection circuit 3 through
UN / STOP terminal input, 4 is a RUN / STOP switch with a built-in PLC connected to the RUN detection circuit 3, 5 is a RUN display such as a light emitting diode connected to the microprocessor 7 via the display interface 6, and 8 is a programming tool. A programming tool connected to the microprocessor 7 via the interface 9 for the system; 11a, a system memory connected to the microprocessor 7;
2 is an output latch memory 14 from the output interface 13
, And the various memories 10, 11a, 14, the interfaces 2, 6, 9, 13, and the RUN detection circuit 3 are bus-connected to the microprocessor 7, P as a whole
Construct LC15.

Next, the operation of the above-mentioned conventional programmable controller will be described.

[0005] In the PLC 15 configured as described above, the RUN detection circuit 3 outputs the RUN / RUN input from the external connection terminal of the PLC 15 via the input interface 2.
ON / OFF signal of STOP terminal input 1 and PLC15
An ON / OFF signal of the built-in RUN / STOP switch 4 is determined by an OR circuit, and if either one is ON, it is recognized as ON.

For example, in the case where RUN is defined as ON and STOP is defined as OFF, a RUN signal is sent to the microprocessor 7 if it is ON, and the microprocessor 7 receiving the RUN signal transmits the RUN signal through the display interface 6. The RUN indicator 5 is turned on, and the program memory 10 is operated in accordance with the instruction procedure of the system memory 11a.
Is executed, and the operation result is output from the output latch memory 14 to the output interface 1.
3 to a number of output loads 12.

On the other hand, RUN / STOP terminal inputs 1 and P
If both the RUN / STOP switches 4 with built-in LC are OFF, the RUN detection circuit 3 sends the ST to the microprocessor 7.
The microprocessor 7 that has sent the OP signal and received the STOP signal turns off the RUN indicator 5 and stops the output load 12.

The program memory 10 previously stores a sequence program programmed by the programming tool 8 via the programming tool interface 9 and the microprocessor 7.

[0009]

In the conventional RUN detection circuit 3 configured as described above, the RUN / STOP terminal input 1 and the RUN / STOP switch 4 with built-in PLC are turned on.
Since / OFF is detected by the OR circuit, if one of them is in the ON state, the ON state is kept irrespective of the change of the input from the other ON to OFF.

Therefore, even if there are a plurality of RUN / STOP inputs, if there is an input that is turned on first, the O
There is a problem that the FF input is ignored.

In addition, the switch 4 with built-in PLC is
-STOP-Remote 3-pole switch. When remote is selected, there is a type in which other RUN / STOP inputs are valid. However, even in this case, there are a plurality of other RUN / STOP inputs. There is a problem with processing at certain times, and it is necessary to use expensive three-pole switches.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. By giving priority to a plurality of RUN / STOP input signals after a post-operation input, a RUN / STOP signal from a PLC external connection terminal or a switch with a built-in PLC is output. An object of the present invention is to provide a RUN / STOP input signal processing method of a programmable controller which can perform RUN / STOP of a PLC by not only the / STOP command but also a plurality of inputs from a programming tool or the like.

[0013] Another object of the present invention is to further select the validity or invalidity of these multiple inputs so that the RUN /
It is an object of the present invention to provide a RUN / STOP input signal processing method of a programmable controller which enables selective use of a STOP signal to simplify operator operations.

[0014]

A RUN / STO of a programmable controller according to the present invention as set forth in claim 1.
The P input signal processing method is a RUN input signal that is an execution command for a programmable controller that generates a large number of ON / OFF output signals by programmable electronic means in response to a large number of ON / OFF input signals.
This is for processing a STOP input signal serving as an execution stop command, for detecting a change in a plurality of RUN / STOP input signals, and for validating a RUN or STOP signal operated later.

According to a second aspect of the present invention, in the RUN / STOP input signal processing method for a programmable controller, the plurality of RUN / STOP input signals are RUN / STOP input by a switch externally connected to the programmable controller. Signal and RUN / S by a switch built in the programmable controller
This includes a TOP input signal and a RUN / STOP input signal from a programming tool that creates a sequence program and transfers the sequence program to the program memory of the programmable controller.

According to a third aspect of the present invention, in the RUN / STOP input signal processing method for a programmable controller, the validity of one or more of the plurality of RUN / STOP signals is determined. It is provided with parameters to be performed. RUN / STOP of the programmable controller according to the invention described in claim 4.
The input signal processing method includes a parameter for designating a general-purpose input terminal of the programmable controller as an external switch connection terminal used as a RUN / STOP terminal input of the programmable controller.

According to the RUN / STOP input signal processing method of the programmable controller according to the fifth aspect of the present invention, the RUN and STOP switches are one push button switch, and the RUN when the switch is operated for the first time is set.
An alternate processing function for inverting the / RUN input state and the RUN / STOP input state at the time of the next operation;
And an indicator for indicating the UN / STOP state.

According to a sixth aspect of the present invention, in the RUN / STOP input signal processing method for a programmable controller, in the RUN / STOP input signal, the RUN or the RUN of the programmable controller immediately before the power of the programmable controller is turned off. A status register for storing a STOP status is provided, and when the power is turned on again, the RUN / STOP status stored in the status register is read out and operated in the same state as the previous time.

[0019]

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the following description, the same or corresponding parts as those in the conventional example of FIG. 9 are denoted by the same reference numerals.

Embodiment 1 FIG. 1 shows a RUN / STO of a programmable controller according to a first embodiment of the present invention.
It is a block diagram showing the P input signal processing system.

In FIG. 1, reference numeral 1 denotes a RUN / STOP terminal input connected to a RUN / STOP detection circuit 17 having a built-in flip-flop circuit via an input interface 2 and an edge detection circuit 16a, and 4 denotes an edge detection circuit. A RUN / STOP switch with a built-in PLC connected to a RUN / STOP detection circuit 17 via 16b, 5 is a RUN display such as a light emitting diode connected to a microprocessor 7 via a display interface 6, and 8 is a programming tool A programming tool connected to the microprocessor 7 and the edge detection circuit 16c via the interface 9, 11b is a system memory connected to the microprocessor 7, and 12 is a connection from the output interface 13 to the microprocessor 7 via the output latch memory 14. Is A large number of output loads 18 are program memories for storing a sequence program created by a user from the programming tool 8 via the programming tool interface 9 and the microprocessor 7, and the various memories 11b, 14, 18 and the interface 2 , 6, 9, 13 and the RUN / STOP detection circuit 17 are bus-connected to the microprocessor 7 to constitute the PLC 19 as a whole.

Next, the operation of the first embodiment will be described.

In the PLC 19 configured as described above, RUN / STOP terminal inputs 1 and P input from the external connection terminal of the PLC 19 via the input interface 2
The RUN / STOP signal from the programming tool 8 which is input via the LC built-in RUN / STOP switch 4 and the programming tool interface 9 is detected by the edge detection circuits 16a, 16b, 16c to detect rising and falling, and the rising signal is detected. The OR signal (logical sum signal) sets the flip-flop circuit of the RUN / STOP detection circuit 17, and the OR signal (logical sum signal) of the falling signal resets the flip-flop circuit.

For example, when it is defined that the command is a RUN command at the time of rising and a STOP command at the time of falling,
When the flip-flop circuit of the RUN / STOP detection circuit 17 is set, the microprocessor 7 turns on the RUN display 5 via the display interface 6 and also executes a sequence program according to the instruction procedure of the system memory 11b and the contents of the program memory 18. And outputs the operation result from the output latch memory 14 to a number of output loads 12 via the output interface 13.

On the other hand, when the flip-flop circuit of the RUN / STOP detection circuit 17 is reset, the microprocessor 7 turns off the RUN indicator 5 and stops outputting to a large number of output loads 12.

In FIG. 1, the edge detection circuit 16
a, 16b, 16c and RUN / STOP detection circuit 17
Is provided as a hardware circuit.
As described later, the RUN / STOP signal can be detected by software processing of the microprocessor 7.

Embodiment 2 FIG. FIG. 2 shows a memory map in the program memory 1 according to the second embodiment of the present invention. In the second embodiment, a parameter for determining the validity of the RUN / STOP input in the program memory 18 in FIG. An area is added.

In FIG. 2, reference numeral 20 denotes a sequence program in which a program for determining the control content of the PLC 19 is written by the programming tool 8 shown in FIG. 1, and 21 denotes the validity of the RUN / STOP input signal and the capacity of the user program area. , A parameter for setting the validity of the RUN / STOP terminal input 1 and the input terminal number of the PLC 19, a parameter 21b for setting the validity of the RUN / STOP switch 4 built in the PLC 19, Reference numeral 21c denotes a parameter for setting whether or not the RUN / STOP input signal from the programming tool 8 is valid, and reference numeral 21d denotes a parameter for setting whether or not the previous operation storage described later with reference to FIG.

In FIG. 2, setting 1 is a signal valid,
Although the setting 0 indicates that the signal is invalid, the logic of the signal can be defined by the upper digit by setting the setting code number to two digits.

For example, when the RUN is set when the RUN / STOP switch is ON, the setting 11 is set.
When the STOP is set when the UN / STOP switch is ON, the setting is 01, and the parameter is a parameter corresponding to the polarity of the switch.

In FIG. 2, the input terminal numbers of the RUN / STOP terminal inputs 1 are general-purpose inputs X000, X001, X
In this example, X000 is selected from 002,..., Etc., but a PLC having a dedicated RUN / STOP terminal is provided.
Then, such a parameter for specifying the number becomes unnecessary.

However, in this case, there is a demerit that a dedicated terminal must be provided in advance for the RUN / STOP terminal input which the user does not know whether to use.

The writing to the parameter 21 is performed from the programming tool 8 via the programming tool interface 9 and the microprocessor 7.

FIG. 3 shows the PLC for the parameters of FIG.
19 is a flowchart for explaining the operation of FIG.

In FIG. 3, when the PLC 19 is first turned on (step 22), the contents of the parameters shown in FIG. 2 are checked (step 23), and then the RUN /
It is determined whether the signal from the STOP terminal input 1 is valid or invalid according to the contents of the parameter (step 24a).

If it is determined to be valid, at step 25a R
The UN / STOP terminal input 1 is made valid, and step 26 is executed.
In step a, the input terminal number of the RUN / STOP terminal input 1 is read and set, and then the process proceeds to step 24b.

On the other hand, if it is determined in step 24a that it is invalid, the process skips to step 24b.

At step 24b, it is determined whether or not the RUN / STOP switch 4 built in the PLC 19 is made valid as a RUN / STOP command based on the above parameters.

If it is determined in step 24b that "validate", the process proceeds to step 25b, where RUN / ST is executed.
After setting the OP switch 4 to valid, the process proceeds to step 24c.

On the other hand, if it is determined in step 24b to "invalidate", the process skips to step 24c.

In step 24c, RUN / STOP from the programming tool 8 is performed based on the above parameters.
Determines whether the command is valid.

If it is determined in step 24c that "validate", the RUN / STOP command from the programming tool 8 is set to be valid in step 26c, and the process ends. On the other hand, if it is determined to "invalidate" in step 24c, the process is immediately terminated.

It should be noted that the above-mentioned step 26a is executed in RUN / ST
If the OP terminal input 1 is input from the dedicated terminal of the PLC 19, it is unnecessary.

As described above, in selecting the validity of various RUN / STOP signals, the output of the edge detection circuits 16a, 16b and 16c shown in FIG. RUN / STOP detection circuit 1
7.

Embodiment 3 4 to 6 illustrate the edge detection circuits 16a, 16b, 16c and RUN /
The STOP detection circuit 17 is abolished, and various RUN / STOP
6 is a flowchart for explaining the operation when the P signal is supplied to the microprocessor 7 as it is and the same operation is performed by software of the microprocessor 7.

In the following description, the RUN / STOP terminal input is abbreviated as signal a, the built-in RUN / STOP switch as signal b, and the RUN / STOP signal from the programming tool 8 as signal c. In the third embodiment,
The signals a and b are RUN when the switch is ON, and STOP when the switch is OFF, whereas the signal c is an example in which each of RUN and STOP is a pair of signals at two separate points.

In FIG. 4, first, registers 4 and 5, which will be described later, are set to logic 1 (step 29).
It is determined whether the LC 19 is currently in the RUN state or the STOP state (step 30).

If it is determined in step 30 that the PLC 19 is in the RUN state, the flow advances to step 31 to clear the registers 4 and 5 for storing the STOP command based on the signals a and b. Proceed to 32a.

In step 32a, it is determined whether or not the signal a is valid according to the parameters shown in FIG. 2. If the signal a is valid, the process proceeds to step 33a. If invalid, the process proceeds to a similar step 32b relating to the signal b. Hereinafter, the processing related to the signal c is performed in the same manner, and the process returns to the step S30.

The subroutine calls 1, 2, and 3 shown in steps 33a, 33b, and 33c are steps for switching the PLC 19 from RUN to STOP, as will be described later with reference to FIG.

In step 30, the current PLC
If it is determined that 19 is in the STOP state, the process proceeds to step 34 to clear registers 1 and 2 described later, and then proceeds to step 35a. Here, register 1,
Numeral 2 is for storing a RUN command by signals a and b.

In step 35a, it is determined whether or not the signal a is valid according to the parameters shown in FIG. 2. If it is valid, the flow proceeds to step 36a, and if it is invalid, the flow proceeds to the same step 35b relating to the signal b. Hereinafter, the processing related to the signal c is performed in the same manner, and the process returns to the step S30.

The subroutine calls 4, 5, and 6 shown in steps 36a, 36b, and 36c are steps for switching the PLC 19 from STOP to RUN, as will be described later with reference to FIG.

In FIG. 5, reference numeral 33A denotes a start step of a subroutine program corresponding to the subroutine call 33a in FIG. 4. In step 37a, ON / OFF of the signal a is determined. After writing logic 1 into register 1 to store that it was ON,
Return to the main routine.

On the other hand, when it is determined in step 37a that the RUN input is OFF, step 39a
Then, it is determined whether or not the content of the register 1 is logic 1. Here, if the content of register 1 is logic 1,
After the PLC 19 is stopped in step 40a, the process returns to step 30 in FIG. However, when the content of the register 1 is not 1, the process immediately returns to the main routine of FIG.

Reference numeral 33B denotes a step for starting a subroutine program for the subroutine call 33b for the signal b. The subroutine program for the signal b is the same as the subroutine program for the signal a.
With these steps, if the PLC 19 is currently in the RUN state, the switch of either the signal a or the signal b is changed from ON to O.
The change to FF causes the PLC 19 to become STOP.

Reference numeral 33C denotes a start step of the subroutine program for the subroutine call 33c relating to the signal c. In step 37c, it is determined whether the STOP signal c is ON or OFF. If the STOP signal c is ON, the PLC 19 is stopped in step 40c and the process returns to step 30 in FIG. 4. If the STOP signal c is OFF, the process returns to the main routine in FIG. Return.

In FIG. 6, reference numeral 36A denotes a start step of a subroutine program corresponding to the subroutine call 36a in FIG. 4. In step 41a, ON / OFF of the signal a is determined. Then, in order to store the fact that it was OFF, a logic 1 is written in the register 4 and then the process returns to the main routine of FIG.

On the other hand, if it is determined in step 41a that the RUN input is ON, the flow advances to step 43a to determine whether or not the contents of the register 4 are logic 1. If the content of the register 4 is logic 1, step 4
After the PLC 19 is RUN at 4a, step 3 of FIG.
It returns to 0, and when it is determined that the contents of the register 4 are not 1, the process returns to the main routine of FIG.

Reference numeral 36B denotes a step for starting a subroutine program for the subroutine call 36b for the signal b. The subroutine program for the signal b is the same as the subroutine program for the signal a.
According to these steps, if the PLC 19 is actually a STOP, the switch of either the signal a or the signal b is changed from OFF to O.
By changing to N, the PLC 19 becomes RUN.

Reference numeral 36C denotes a start step of a subroutine program for the subroutine call 36c relating to the signal c. In step 41c, the ON / OFF of the RUN signal c is determined. If this is ON, the PLC 19 is RUN in step 44c, and The process returns to step 30 in FIG. 4. If it is OFF, the process returns to the main routine in FIG.

When the power of the PLC 19 is turned on, the RU has already been set.
When the N / STOP switch is turned on, FIG.
Since the registers 4 and 5 are set to logic 1 in step 29, the comparison is coincident in, for example, step 43a in FIG. 6, and the RUN of the PLC 19 is executed in step 44a.

Embodiment 4 FIG. 7 shows a flowchart for responding to an alternate RUN / STOP signal in which the PLC 19 is changed from STOP to RUN in the first operation and RUN is changed to STOP in the next operation using one push button.

In FIG. 7, in step 46, the PLC 1
9 is currently RUN or STOP, and R
If it is UN, the process proceeds to step 47, where the RUN indicator 5 is turned on, and then proceeds to step 48.

In step 48, the PLC 19 transmits the RU
If it is in the N state, it waits for the RUN / STOP input to turn on.
19 is stopped, and the process returns to step 46.

On the other hand, in step 46, the PLC 19
Is determined to be the current STOP, the process proceeds to step 50, where the RUN indicator 5 is turned off, and the process proceeds to step 51. When the PLC 19 is in the STOP state in step 51, the process waits for the RUN / STOP input to be turned ON. When the RUN / STOP input is turned ON, the PLC 19 is RUN in step 52, and then returns to step 46.

In this manner, whether or not an alternate (alternating) operation is performed by one push button can be determined by setting the parameters of FIG. 2 by setting the RUN / STOP according to the user's preference. It can be handled.

Embodiment 5 FIG. 8 is a flow chart for explaining the rhedium function for storing the previous state and automatically setting the same state when the PLC 19 is turned on again after the power is turned off.

In FIG. 8, first, when the power is turned on to the PLC 19 (step 55), it is determined whether or not the setting of the parameter 21d in FIG. 2 is valid (step 56). Proceed to PLC
After setting STOP to 19, the process proceeds to step 61 described later.

On the other hand, if it is determined in step 56 that the data is valid, the flow advances to step 57 to read the status register described later. Next, at step 58, when the contents of the status register read at step 57 are in the RUN state, the PLC 19 is set to RUN at step 59.
Set 19 to STOP. With these steps, PL
C19 is in the same RUN or STOP state as before the power failure.

Thereafter, in step 61, a RUN / STOP switching operation as shown in FIGS. 4 to 6, for example, is performed.

Next, at step 62, the PLC1
9 is detected to be turned off, and when this is detected, in step 63, the current RUN / S is executed immediately after the power is turned off.
The TOP state is stored in a state register (not shown), and the process ends. As this status register, a memory that does not lose its memory even during a power failure, such as a RAM memory or an EEPROM memory backed up by a battery, is used.

As described above, according to the present invention, a plurality of RUN /
Detects rise or fall of each input signal in response to STOP input (referred to as edge detection)
RU only when a signal contrary to the current state is input
The state of N or STOP is changed.

This is because, for example, the status of the current PLC is RU
If N, when the STOP command is input, PLC1
9 is set to STOP, and if the current PLC state is SPTOP, when the RUN command is input, the PLC 19 is set to R
UN.

Further, parameters to be written and set by an engineer in the initial setting stage of the PLC 19 can be provided to limit the types of RUN / STOP signals to be used as required.

As a result, the RUN / STOP command giving priority to the rear operation is given to the PLC 19, and confusion of the operator's operation is avoided. Therefore, various RUN / STOP switches can be provided according to the purpose of the operator.

[0077]

As is apparent from the above description, the RUN / STOP of the programmable controller according to the present invention.
According to the input signal processing method, simple operation with priority on rear input can be performed without confusion of the operator in response to a plurality of RUN / STOP input commands, so that RUN / STOP inputs for various purposes can be effectively used.

Accordingly, even if various RUN / STOP inputs are provided as standard equipment as PLCs, only RUN / STOP inputs that are truly necessary in correspondence with the actual machine are limited to the RUN / STOP inputs, and the operation is simplified. You can also plan.

Further, since a RUN / STOP terminal input designating a general-purpose input terminal by setting parameters can be used, a dedicated RUN / STOP input terminal can be eliminated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a programmable controller using a RUN / STOP input method according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a parameter memory map according to a second embodiment of the present invention;

FIG. 3 is a parameter determination flowchart according to Embodiment 2 of the present invention.

FIG. 4 is a flowchart illustrating an operation according to the third embodiment of the present invention.

FIG. 5 is a flowchart illustrating an operation according to the third embodiment of the present invention.

FIG. 6 is a flowchart illustrating an operation according to the third embodiment of the present invention.

FIG. 7 shows an alternate RU of Embodiment 4 of the present invention.
It is a flowchart for operation | movement description of N / STOP.

FIG. 8 is a flowchart illustrating a power failure storage operation in a RUN / STOP state according to the fifth embodiment of the present invention.

FIG. 9 is a configuration diagram of a conventional programmable controller using a RUN / STOP input method.

[Explanation of symbols]

1 RUN / STOP terminal input, 4 PLC built-in RUN
/ STOP switch, 5 RUN indicator, 8 programming tools, 16a, 16b, 16c Edge detection circuit, 17 RUN / STOP detection circuit, 18 program memory, 19 programmable controller (PL
C), 21 parameters, 49, 52 Alternate operation step, 57 Status register read step.

Claims (6)

[Claims] 1. In response to a number of ON / OFF input signals, a number of ON / OFF signals are programmable by electronic means.
This is for processing a RUN input signal serving as an execution command and a STOP input signal serving as an execution stop command for a programmable controller that generates an OFF output signal, and detects a change in a plurality of RUN / STOP input signals. Detecting and enabling a later operated RUN or STOP signal.
UN / STOP input signal processing method. 2. The system according to claim 1, wherein the plurality of RUN / STOP input signals include a RUN / STOP input signal from a switch connected to the outside of the programmable controller, a RUN / STOP input signal from a switch built in the programmable controller, and a sequence. 2. The RUN / STOP input signal processing method for a programmable controller according to claim 1, further comprising a RUN / STOP input signal from a programming tool that creates a program and transfers a sequence program to a program memory of the programmable controller. 3. The programmable controller according to claim 1, further comprising a parameter for determining a selection of validity of any or a plurality of items of the plurality of RUN / STOP signals. RUN / ST
OP input signal processing method. 4. The RU of the programmable controller
4. The RUN / STOP input signal processing of the programmable controller according to claim 2, wherein a parameter for specifying a general-purpose input terminal of the programmable controller is provided as an external switch connection terminal used as an N / STOP terminal input. method. 5. The switch of RUN and STOP is a single push button switch, and the RUN / STOP input state at the time of the first operation of this switch and the RUN / STOP input state at the time of the next operation.
5. The RUN / STOP input signal of a programmable controller according to claim 1, further comprising an alternate processing function for inverting a STOP input state and an indicator for indicating a current RUN / STOP state. Processing method. 6. A status register for storing the RUN or STOP status of the programmable controller immediately before the power of the programmable controller is turned off in the RUN / STOP input signal, and the status register stores the status when the power is turned on again. 6. The RUN / STOP input signal processing method for a programmable controller according to claim 1, wherein the RUN / STOP state is read out and operated in the same state as the previous time.