JPS63113704A - Programmable controller having measurement display function - Google Patents

Abstract

PURPOSE:To easily incorporate a display program to a programmable controller with use of a ladder language with no conversion of other program language including a basic language, etc., by giving a call instruction to display the control state in an input mode of a program produced by a ladder chart. CONSTITUTION:A call instruction 100 is put in the middle of the sequence control of a ladder chart and a user has input of an instruction SUB for shift to a subroutine together with its address number as a call instruction as shown in a diagram. The call instruction put into the ladder chart is executed in a ladder language to avoid such a troublesome job where a programming action is carried out after conversion into a basic language, etc. Thus a display program is supplied in a simple operation. When a call instruction is received, a subroutine is started by the call instruction to display the state of the sequence control. Then, the actual temperature of an electric furnace, for example, is measured. This measured temperature is supplied to a CPU8 and converted into the display data by a display data converting means 7.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention measures the state of an object to be controlled by PID control (control based on proportional, integral, and differential operations), etc.
This invention relates to an improvement of a programmable controller having a measurement display function that can be displayed on a cathode ray tube screen.

[Prior Art] Programmable controllers that perform sequence control in various automatic processing lines, steel processing lines, and other production facilities in which many machines are combined are well known. This enables complex and advanced control.

In particular, in recent years, control objects such as computers,
Devices, robots, etc. are organically connected, and high-performance sequence control is required to sequence control these devices, monitor the entire line, detect abnormalities, track/position, or measure.

The present invention performs such sequence control, and controls the control status of PID control etc. for process control using a CRT.
The main configuration of a conventional programmable controller is shown in FIG. 4, which is displayed on a screen.

In Fig. 4, (1) is a graphical system that allows the program of a sequence circuit to be input in a ladder language based on a ladder chart diagram without changing the circuit diagram.
Programming panel (GP P), (2) is GP
PI according to the ladder chart input from P (1)
A central processing unit (CP) that performs sequence control processing such as D control.
U) and (3) are intelligent units that have a built-in program such as a basic program for displaying temperature changes when controlling the temperature of an object to be PID controlled, such as an electric furnace or a reaction tank; (4) is a display unit that inputs display data from the intelligent unit (3), converts it into a video signal for CRT display, and outputs it.
5) is a CRT display that displays images based on the video signal from the display unit (4), and (6) is an input/output unit (I1) that inputs and outputs data signals to and from external devices such as controlled objects.
0) It is a unit.

A programmable controller with such a configuration performs PID control using proportional, differential, and integral operations, and the sequence control program for this is based on the GPP (1
) can be input.

This GPP (1) inputs sequence circuits graphically, without converting them into basic language etc.
For example, by inputting ladder words such as X for input, Y for output, and LD (load) for logical operation circuit, you can easily create a sequence program, and this also allows you to change the program. It's easy.

By the way, when PID control is performed according to the program input in this way, the CRT display (5)
The control status is displayed as an image, but conventionally this is done in the intelligent unit (3), and the control data processed in the ladder language is converted into display data using a display program such as Basic. The control state measured by this conversion is displayed as an image.

[Points to be solved by the invention]However, in the intelligent unit (3) for display data conversion, a control program for displaying an image must be created in a basic language, etc. There is a problem that creation is complicated and time-consuming, and in particular, the display program must be created by the user himself, so there is a demand for simplification of the work.

Furthermore, when inputting a program in a basic language or the like, it is necessary to perform processing such as debugging the created program, which is also a waste of time.

Purpose of the Invention The present invention has been made in view of the above-mentioned conventional problems.
The purpose is to provide a programmable controller having a measurement display function that allows easy creation of screen display programs in ladder language.

[Means for Solving the Problems] In order to achieve the above object, the program run controller having a measurement display function according to the present invention is provided with a display data converting means in the CPU, and this display data converting means is a ladder chart diagram. It has program data that is read out by a call command built into the computer, converts the state of a controlled object into display data for CRT display, and is configured by, for example, a microcomputer.

The present invention is characterized in that a call command for displaying the control is given when inputting a program using a ladder chart diagram.

[Operation] According to the above configuration, program data for CRT display is read by a call command incorporated in the ladder diagram during PID control, and if sequence control is performed in the main routine. CRT display control corresponds to being performed in a subroutine, and arithmetic processing for displaying the status of the controlled object is performed in accordance with the program data read out in this way.

Therefore, the user can easily create a program for CRT display by giving a call command for displaying the control status in the ladder language when inputting a sequence program based on a ladder chart diagram.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a programmable controller having a measurement display function. In the figure, (7) has display program data read out by a call command, and a display for displaying the state of the controlled object on a CRT. Display data conversion means (8) for converting into data is a CPU incorporating this display data conversion means. In the embodiment, a display when, for example, PID control is performed on the temperature state inside the electric furnace will be described.

First, as shown in FIG. 2, a call instruction 100 is incorporated in the middle of the sequence control of the ladder chart diagram, and the user calls the subroutine transition command SUB as shown in the figure.
and its address NO as a call command.

The call commands incorporated in such ladder chart diagrams are performed in the ladder language, and there is no need to convert and program them into a basic language as in the past, and the program for display can be entered with a simple operation. becomes possible.

When a call command is input in this way, a subroutine for displaying the control status is started by the call command during sequence control, and the actual temperature of the electric furnace is measured. The temperature measured by the CPU (
8), and the measured temperature is converted into display data by the display data conversion means (7). Then, the display data is supplied from the display data conversion means (7) to the display unit (4), where it is converted into a video signal for image display, and this video signal is sent to the CRT display (5).
is supplied to

Therefore, for example, as shown in FIG.
The temperatures measured at locations , B, and C are displayed as a bar graph or the like.

In addition, in the present invention, a desired display state can be ensured by not only simply incorporating a call command into the ladder chart diagram, but also inputting settings and changes of the program necessary for image display in the ladder language.

[Effects of the Invention] As explained above, according to the present invention, when programming a sequence control circuit using a ladder chart diagram, a program for image display can also be executed at the same time, and other programs such as basic etc. without converting to a programming language.
Display programs can be easily incorporated using the ladder language.

Therefore, it is no longer necessary to create a user program in a basic language or the like and debug time when inputting a program, which has been done in the past, and it is possible to reduce the work required to display images of the controlled object.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing a preferred embodiment of a programmable controller having a measurement display function according to the present invention, FIG. 2 is a ladder chart diagram of the present invention, and FIG. 3 is a diagram showing electric furnace temperature on a CRT display. A display diagram of the control state, FIG. 4 is a configuration diagram showing a conventional device, and FIG. 5 is a conventional ladder chart diagram. In the figure, (1) is graphic programming ψ
Panel (GPP), (2) is a conventional CPU, (3) is an intelligent unit, (4) is a display unit, (5)
) is a CRT display, (6) is an I10 unit, (7) is a display data conversion means, and (8) is a CPU of the present invention. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] (1) Graphic programming in which program data is input based on a ladder chart diagram. In a programmable controller that has a panel and has a measurement display function that displays the measured control state of an object that is sequence-controlled by a CPU on a CRT screen,
The CPU is provided with display data converting means that has display program data read out by a call command incorporated in the ladder chart diagram and converts the state of the controlled object into display data for CRT display, A programmable controller having a measurement display function, characterized in that a call command for displaying a control state is given when a program is input.