JP2653346B2 - 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 programmable controller, and more particularly, to a programmable controller for monitoring input / output data.

[0002]

2. Description of the Related Art Conventionally, a programmable controller of this type displays a ladder diagram on a CRT screen in a system service process, and turns on / off devices (input / output contacts, external relay contacts, etc.) shown in the ladder diagram. In general, the state is displayed and monitored by a change in luminance.

[0003] In this way, it is possible to comprehend the ladder diagram displayed on at least one screen and the state of the input / output data associated therewith.

[0004]

However, the user program of this type of programmable controller is usually quite large, whereas the display area of the CRT screen is limited. Only the state of input / output data in a specific narrow range can be simultaneously displayed on the CRT screen.

In other words, this type of monitor based on a ladder diagram has the inconvenience that the display screen must be switched to a corresponding ladder diagram area in order to monitor input / output data which are greatly separated in the ladder diagram. is there.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has as its object to provide a programmable program having a function of simultaneously monitoring a plurality of input / output data at arbitrary positions in a ladder diagram on the same screen. To provide a controller.

[0007]

According to the present invention, in order to achieve the above object, the input / output shown in a ladder diagram is selectively used.
Registration control means for registering the input / output specification information in the first storage means in response to a key input operation for specifying
Sample control means for cyclically sampling the input / output state specified by the input / output specification information registered in the first storage means; and input / output state sampled by the sample control means for a certain number of times in the past. Second storage means for storing only the respective samples, and each sample stored in the second storage means.
When displaying the input / output status of each time in chronological order along the time axis
Sequence monitoring means and programs related to input / output data
And ladder diagram monitoring means for displaying the following , and monitor transition means for transitioning from the monitoring state by the ladder diagram monitoring means to the monitoring state by the time series monitoring means.

[0008]

The registration control means selects the input / output shown in the ladder diagram.
In response to a key input operation for selectively specifying, the input / output specification information is registered in the first storage means, and the sample control means uses the input / output specification information registered in the first storage means. The specified input / output state is sampled cyclically. Then, the second storage means stores the input / output states sampled by the sample control means for a fixed number of times in the past, and the time-series monitoring means stores the input / output states in the second storage means.
The input / output state of each sampled time along the time axis
Display in columns.

On the other hand, ladder diagram monitoring means input and output data
Display programs related to . And
The monitor shifting means shifts from the monitoring state by the ladder diagram monitoring means to the monitoring state by the time series monitoring means.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a programmable controller according to the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing an overall schematic configuration of a programmable controller to which the present invention is applied.

In this programmable controller, the microprocessor 1 is the center of overall control.

The system program memory 2 stores a system program executed by the microprocessor 1.

The working memory 3 is used by the microprocessor 1 as a temporary storage area for various variable data.

The user program memory 4 stores a sequence control program arbitrarily set by the user.

An input / output device (general term for an input circuit and an output circuit) 5 including an input interface to which an external input signal is applied and an output interface for sending an external output signal, and a buffer of input / output data corresponding to the input / output device An I / O memory 6 serving as a memory.

Further, the system includes a keyboard 7 used for giving various operation commands to the microprocessor 1 and for creating and inputting a user program, and a display device 8 for displaying a monitor.

As is well known, this type of programmable
The execution operation of the user program in the controller
User instructions (for example, corresponding to a ladder diagram) are sequentially read from the user program memory 4, arithmetic processing is performed with reference to input / output data stored in the I / O memory 6 according to each user instruction, and the processing result is obtained. Is to update the specified output data of the I / O memory 6.

In a time zone different from the execution of a series of user programs, input data supplied to the input circuit is collectively written to a predetermined area of the I / O memory 6 (input update) and the I / O is updated. An operation (output update) of collectively transferring output data in a predetermined area of the memory 6 to the output circuit is performed.

In still another time zone, the system service program stored in the system program memory 2 is read out as needed and the input / output monitor,
Various operations (system services) such as correction of a user program are performed.

The system program stored in the system program memory 2 is stored in the microprocessor 1
, The input update processing, the user program execution processing, the output update processing, the system service processing, and the like are cyclically performed.

Further, in order to realize the present invention, it is necessary to provide the following means for functioning in the system service processing in addition to the above-described basic configuration of the programmable controller.

That is, the microprocessor 1 has a registration control means for registering input / output designation information in the first storage means, and an input / output state designated by the input / output designation information registered in the first storage means. And a sample control means for cyclically sampling the data.

The working memory 3 has a function as first storage means for registering input / output designation information.

The display device 8 is provided with a function as a second storage means (video RAM) for storing the input / output states sampled by the sample control means for a fixed number of times in the past. It has a function as an image display means for displaying the input / output state of each sample stored in the storage means in a time-series manner along the time axis.

The input / output is designated by the keyboard 7. In this case, the keys are operated in the order shown in FIG.

That is, the keyboard 7 has a time-series monitor key 71, types of input / output data, for example, input / output signals T / C of a timer and a counter, input / output signals i / o of a control system.
A selection key 72 for selecting an input / output number, a number key 73 for keying in an input / output number, an entry key 74 for determining display on the screen of the display device 8, and an end key 75 are provided.

After the time-series monitor key 71 is keyed in, these keys 72 to 74 are repeatedly keyed in the order of the selection key 72, the number key 73, and the entry key 74.

This repetition key-in is performed for the number of input / output points to be monitored in time series.
Usually, six times are preferred. After these key-ins, the end key 75 is keyed-in.

The operation will be described below with reference to a flowchart.

As shown in the flowchart of the whole system in FIG. 4, in a step (402) following the initial processing in the step (401), a key input signal from the keyboard 7 is sequentially read by the microprocessor 1.

In step (403), the system service program stored in the system program memory 2 is read out as needed, and system service processing such as correction of a user program is performed.

In step (404), the input is updated by transferring the input data supplied to the input / output device 5 to the input area of the I / O memory 6.

In step (405), if the execution mode flag F ₀ is not the execution mode of the user program, the output of the input / output device 5 is cleared in the following step (406) and the key input reading in step (402) is performed. Returning, steps (402) to (406) are repeated until the execution mode is set.

Here, in the case of the execution mode, the routine proceeds to the routine after step (407). First, step (4)
07), the program counter PC is cleared. At the next step (408), the instruction indicated by the program counter PC is read from the user program memory 4, and at the next step (409), it is determined whether the read instruction is an END instruction. judge.

Here, if it is an instruction other than the END instruction,
At step (410), the instruction is executed by a known interpreter process. Then, at step (411), the program counter PC is incremented, and the process returns to the instruction reading at step (408).

If the instruction is an END instruction, step (4)
Proceeding to 12), the output data of the I / O memory 6 is transferred to the input / output device 5, and the output is updated as an external output signal.

When the output is updated, the process returns to step (402) for key input reading.

In such a round execution operation, the monitor display is performed in the system service processing in step (403).

The system service processing is executed by the routine shown in the flowchart of FIG. 5, and this execution is performed after all the key input signals read by the microprocessor 1 are temporarily stored in the working memory 3.

In the first step (501) in FIG. 5, if the key input signal read from the working memory 3 is the time series monitor key 71, the time series monitor flag F ₁
Is set.

[0042] When the time-series monitor flag F ₁ is set, the flow advances to step (502), the status area located below example of the screen of the display device 8, is displayed indicating that the registered key is keyed input and output It is ready to be specified.

In this state, when the key-in is performed in the order of the selection key 72, the number key 73, and the entry key 74, the input / output numbers to be monitored in time series are input / output designation information areas in the working memory 3 (see FIG. 6). Registered in. This input / output designation information area corresponds to a first storage unit.

After repeating this, for example, six times,
When the end key 75 is pressed in, the time-series monitor registration process ends, and the process proceeds to the input update of step (404) in FIG.

If it is determined in step (501) that the key-in is other than the input / output designation, the flow advances to the routine after step (503).

First, in step (503), it is determined whether or not the key input signal is a key-in signal in a predetermined time-series monitor mode.

Here, if it is not the time series monitor mode,
Steps (504) to (507) are skipped and the process proceeds to another key input process of step (508).

[0048] The determining, when it is determined that the time is series monitor mode, whether time-series monitor mode flag F ₂ is set continues at step (504).

[0049] Here, the time-series monitor mode if the flag F ₂ is not set, the next step (505) at the input and output data registered in the output specifying information area B ₁ .about.B ₆ (see FIG. 6) Whether or not there is a change is checked based on the contents of the corresponding input / output data stored in the I / O memory 6.

In order to check the change of the input / output data, the past state must be stored. Therefore, the working memory 3 has two entries for each registered input / output.
A bit FIFO (First In First Out) stack is provided to determine whether data matches before and after each sample.

Under these conditions, the past and present states of the input / output data are compared, and if there is a change, the subsequent step (50)
Sets the time-series monitor flag F ₃ at 6).

If it is determined in step (505) that there is no change in the input / output data, the flow advances to another key input processing in step (508).

In the other key input processing in step (508), as shown in FIG.
Display a ladder diagram. The monitor processing by the display of the ladder diagram is well known from various documents and will not be described here.

When the ladder monitor ends in step (508) in this manner, the flow proceeds to the input update in step (404) in FIG.

On the other hand, if the time-series monitor flag F ₃ is set at step (506), it enters the next round execution cycle, the time-series monitor flag F ₃ is set at step (504) Is determined, and step (5)
The process proceeds to the time series monitor display process of 07).

The time-series monitor display process of step (507) is executed as shown in the flowchart of FIG.

First, in step (701), it is determined by an external timer whether or not the sampling period T seconds has elapsed.

If the time does not elapse, the process ends.
The process proceeds to another input process of step (508). On the other hand, when the time has elapsed, the count-up output from the external timer is applied to the microprocessor as an interrupt signal. Then
In the microprocessor 1, the timer flag is, for example, "1".
Is set to

[0059] When the timer flag is set, followed by step (702), input of the I / O memory 6 designated by the registered number to the start address B ₁ O specifiable information area (Fig. 6) Read the output data.

Next, proceeding to step (703), the input / output data stored in step (702) is converted into a display code for accessing the character generator.

At step (704), the converted display code is sent to the video RAM of the display device 8.

As shown in FIG. 8, the video RAM of the display device 8 is provided with ₅₀ display data areas A _{1 to} A ₅₀ (corresponding to the second storage means). Can be specified by the value of the pointer N (1 to 50). Each of the display data areas A _{1 to} A ₅₀
Can store six input / output data.

As shown in FIG. 9, each of the display data areas A _{1 to} A ₅₀ corresponds to each column when the lower half of the CRT screen of the display device 8 is divided into 50 columns in the horizontal direction and 6 columns in the vertical direction. and, therefore, when six display data for each area a ₁ to a ₅₀ is written, a time chart of the vertical one column in the CRT display screen is drawn as shown in the display area in FIG.

It should be noted that, based on the coded display data, “￣” for displaying “H” is displayed on the CRT screen of the display device 8.
Or for the process of displaying “_” for “L”,
As is well known, video RAM, character generator, CR
This is performed by a T controller or the like.

In the following step (705), the registration I / O
Determines whether or not completed the input and output data indicated by number input, if not completed, the process returns to step (702), which is specified by the following address B ₂ O specifiable information area , The same processing (steps (702) to (704)) is executed, and thereafter the processing for the addresses B _{3 to} B ₆ is completed, and the value of the display area pointer N is changed from “1” to “2”. Update.

Next, the processing of steps (702) to (706) is skipped until T seconds have elapsed, and the same processing corresponding to the value "2" of the display area pointer N is performed as T seconds elapses. .

That is, steps (702) to (70)
When the process of 4) is repeated six times, the display codes for one column in the vertical direction are sequentially transferred to the display device 8. Then, in the video RAM (not shown) on the display device 8 side, new display data for one vertical column is shifted rightward in the horizontal direction by one column on the display screen, and is displayed in the next area. .

Thereafter, if the value of the display area pointer N reaches "50" as a result of repeatedly executing the steps (701) to (706), the six display data of each sampling time are again transmitted from the left end of the screen. Control for displaying is performed.

On the other hand, in this embodiment, when the ladder diagram is displayed on the entire CRT screen and the process shifts to the time-series monitoring process described above, the previously displayed ladder diagram is reduced in the vertical direction. A time chart according to the present invention is displayed in a substantially upper half of the CRT screen, and in a substantially lower half of the CRT screen.

Such a ladder diagram reduction process is already known and will not be described in detail. For example, in the ladder diagram data corresponding to one screen of a CRT screen, the device number assigned to each input / output device is determined. By removing only the ladder diagram as shown in FIG. 1B and closing the gap, the ladder diagram can be reduced to half in the vertical direction.

As described above, in this embodiment, when a change occurs in the designated input / output data among the input / output data already registered in the I / O memory 6 during the ladder monitor, the screen of the display device 8 is displayed. The state shown in FIG. 1A changes to the state shown in FIG. 1B, and the specified input / output data can be displayed in chronological order together with the ladder diagram.

Therefore, as long as the input / output numbers or the like to be monitored are registered in advance, even if the input / output cannot be simultaneously displayed on one screen as a ladder diagram, these can be simultaneously displayed on one screen. In addition, monitoring can be performed in time series, and the monitoring function of this type of programmable controller can be made more convenient.

Also, in this embodiment, in particular, in response to a change in any of the registered inputs and outputs, the system automatically shifts from the ladder diagram monitor to the time-series monitor process. The timing at which the state of a specific input / output has changed can be easily detected.

Further, in this embodiment, when a change occurs in any of the inputs and outputs during the ladder diagram monitor, the ladder diagram and the time chart are simultaneously displayed in the upper and lower halves of the screen. , The specified input / output state can be monitored in chronological order, and it is possible to simultaneously grasp the circuit and the timing.

In the above-described embodiment, the number of samples that can be simultaneously displayed is set to 50, and the sample period is fixed to T seconds. However, if the number of samples and the period can be programmed, the usability can be further improved. Of course, it can be improved.

[0076]

As described above, according to the configuration of the present invention, when the created ladder program is long enough to fit on the monitor screen, the ladder diagram monitor state is set,
A user-friendly programmable controller can be provided, such as changing to a time-series monitor when the program becomes long.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory diagrams of a monitor display state in a programmable controller to which the present invention is applied;

FIG. 2 is a block diagram showing a schematic configuration of a programmable controller to which the present invention is applied.

FIG. 3 is an explanatory diagram of key operation.

FIG. 4 is a flowchart of the entire system of the present invention.

FIG. 5 is a flowchart of a system program process according to the present invention.

FIG. 6 is an explanatory diagram of an input / output designation information area.

FIG. 7 is a flowchart of a time-series monitor display process according to the present invention.

FIG. 8 is an explanatory diagram of a display data area of a video RAM.

FIG. 9 is an explanatory diagram showing correspondence between writing to a display data area and a screen state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Microprocessor 2 System program memory 3 Working memory 4 User program memory 5 I / O device 6 I / O memory 7 Keyboard 8 Display device

Claims (1)

(57) [Claims] An input / output shown in a ladder diagram is selectively designated by a finger.
A registration control unit for registering the input / output designation information in the first storage unit in response to a key input operation for specifying the input / output designation information registered in the input / output designation information registered in the first storage unit. a sample control means for sampling the state of the output cyclically, a second storage means for storing the state of the sampled output by said sample control means only past fixed number of times, stored in the second storage means Input and output for each sample
Time-series monitor that displays the status in chronological order along the time axis
Means, ladder diagram monitoring means for displaying a program related to input / output data, and monitor transition means for transitioning from a monitoring state by the ladder diagram monitoring means to a monitoring state by the time-series monitoring means. And a programmable controller.