JPH08320708A - Method of collecting real-time display data in programmable controller - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To provide a method of collecting display data in real time without affecting the execution speed of the device. [Configuration] When a screen display is requested from the programming panel of the programmable controller, a display data program is generated separately from the operation program corresponding to the display screen, and the address signal of the data memory included in the instruction of this program is vacant. A decoder that prevents the input of bits is provided, and the address of the data memory included in the instruction of the operation program that does not correspond to the display screen
When the empty bit of the address of the data memory included in the instruction of the display data program corresponding to the display screen is flagged to make it the second address, the address on the bus is the first address. In this case, the data is not stored in the display data storage memory, but when the address on the bus is the second address, the data on the bus is stored in the display data storage memory.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of displaying data in real time, such as displaying the execution state of a user program (hereinafter referred to as an operating program) in a programmable controller.

[0002]

2. Description of the Related Art In a programmable controller used as a controller of a control system, data when a running program is executed is displayed on a screen such as a CRT.
So-called real-time data display is generally performed. For this purpose, it is necessary to collect data (hereinafter referred to as display data) when the operation program is executed in real time. FIG. 3 is a diagram showing a conventional technique. 1 is a CPU, 2 is a program memory, 3 is a data memory and a display data storage area, and 4 is a chip select signal generated based on an address signal of the data memory given by a program instruction. It is a decoder. In the prior art according to FIG. 3, the display data is collected by a display data program provided independently of the operation program. That is, this display data program is, as shown in FIG. 3, added with a command for collecting display data after each command of the operating program that is normally executed, and is displayed by causing the CPU to execute this program. I was collecting data. Here, “command 1, command 2 ... Command n” of the operating program 20 and “command 1, display data collecting command 1, command 2, display data collecting command 2 ... Command n,” of the display data program 21. The display data collection command n ”shows only the portion corresponding to the display screen of the entire operation program.

[0003]

However, it is necessary to add the display data collection command 1, the display data collection command 2, etc. as shown in FIG. 3 only for the purpose of collecting the display data. By executing the display data program having such a configuration, the display data is collected at the same time as the operation program is executed, and the display data designated by the programming panel or the like, for example, the display data is displayed on the CRT screen or the like together with the ladder circuit. Was. Therefore, when the display data is collected, the execution time of the program is longer than when it is not collected, and when a large amount of data is displayed, the execution speed of the device is reduced. Therefore, it is an object of the present invention to provide a method of collecting display data in real time without affecting the execution speed of the device.

[0004]

In order to solve the above problems, the present invention provides a display including a command of a driving program in addition to a driving program corresponding to a display screen when a screen display is requested from a programming panel. A programmable controller configured to generate a data program and execute the display data program instead of executing the operation program corresponding to the display screen, thereby displaying the data in real time on the screen with the execution of the operation program. In the method for collecting real-time display data in the above method, there is provided a decoder for generating a chip select signal of a data memory, the decoder being arranged so as not to input an empty bit of an address signal of the data memory included in the instruction of the program, Luck that does not correspond to the screen The address of the data memory included in the command of the program is used as the first address, and the empty bit of the address of the data memory included in the command of the display data program corresponding to the display screen is flagged to make it the second address. When the address is used, if the address on the bus is the first address, the data is not stored in the display data storage memory, and if the address on the bus is the second address, the data on the bus is stored in the display data storage memory. It is something to store. Further, in a system that requires a plurality of the display data programs, a screen designating instruction is provided for each display data program. When the address on the bus is the second address, the data on the bus is designated by the screen designating instruction. Is stored in the area of the display data storage memory corresponding to.

[0005]

With the above first means, it is not necessary to add a command for display data to the operation program, and the display data can be collected only by changing the access address of the program memory. It is possible to collect display data in real time without the need. Further, by the second means, even when a plurality of programming panels are connected to one programmable controller and a plurality of data display requests are made, it is possible to collect display data in real time without lowering the execution speed of the device. It will be possible.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the present invention. Reference numeral 1 is a CPU, 2 is a program memory in which an operation program 22 and a display data program 23 are stored. Here, “command 1, command 2 ·
.. "Instruction n" shows only the portion corresponding to the display screen of the entire operation program. The most significant bit (ENBIT) of the data memory address included in the instruction of the program is an empty bit, and ENBIT = “Low” at the address of each instruction in the operation program 22.
(Hereinafter, this address is referred to as the first address), and the address of each instruction of the display data program 21 is EN.
BIT = “High” (This address is the second
Of the address). A data memory 3 is an ON / OFF signal for a contact of a program of a programmable controller (for example, a contact of a ladder circuit) or a state signal of an input signal (for example, an ON / OFF signal of a position detection signal of a mechanical device controlled by the programmable controller). ) Data is stored. A decoder 4 decodes an address of the data memory given from the programs 22 and 23 to generate a chip select signal of the data memory 3. The most significant bit (ENBIT) of the address is not input to the decoder 6, but since the most significant bit is an empty bit, the ENBIT at the data memory address given by the program
= "Low" (first address), ENBIT = "High"
Correct access is possible with any of h "(second address). 5 is a display data storage memory, and the data stored here is the CRT of the programming panel.
It is displayed on the screen of a display device or the like. Reference numeral 6 denotes a control circuit, which monitors ENBIT, does not write when ENBIT = "Low", and writes data on the bus to the display data storage memory when ENBIT = "High". Here, the data on the bus means the write data from the CPU to the data memory or the CP from the data memory.
This is the read data to U. In the control circuit 6, the write address of the data storage memory is designated by the write address register in the control circuit. The write address is cleared by the CPU at the start of display data collection and automatically increments by +1 for each write. That is, when the CPU accesses the data memory using the first address, the control circuit does not perform the write operation, and the data is not written in the display data storage memory. When the CPU uses the second address to access the data memory, the control circuit performs a write operation, so that the data on the bus is sequentially written to the display data storage memory. In this device, if there is no request to display the execution state of the operating program in real time, the instruction (instruction 1, 2, ..., N) of the operating program 22 corresponding to the display screen uses the first address. Create a program to access the data memory. In this case, no data is stored in the display data storage memory. On the other hand, when a screen display request is issued from a programming panel or the like and the execution state of the operating program is displayed in real time, the instruction (instruction 1,
2 ,. ． ． , N) instead of display data program 2
3 instructions (instructions 1 ′, 2 ′, ..., N ′) are executed. The display data program 23 commands are stored in the data storage memory sequentially by creating a program to access the data memory using the second address. The above-described embodiment is an embodiment in the case where a request for screen display is generated for only one screen like a system in which one programming panel is connected to one programmable controller. The case where multiple occurrences occur will be described. FIG. 2 is a diagram showing a second embodiment of the present invention, in which display data corresponding to a plurality of screens are simultaneously displayed like a control system in which display devices such as a plurality of programming panels are connected to a common programmable controller. It shows how you can do it. 1 is basically different from FIG. 1 in that the program memory 2 includes a screen designation command in the display data program, and the display data storage memory 5 includes [designated number of screens] number of programming panels (“m” in FIG. 2). ") Is provided for the display data storage memory area, and the control circuit 6 is provided with a write screen designating register. The program memory 2 has an operation program 24 and a display data program 25.
Is stored. Note that the "command 1, command 2 ... Command n" of the operating program 24 and the "screen designation command, command 1 ', command 2' ... Command n '" of the display data program 25 are for all operating programs. Only the part corresponding to the display screen is illustrated. Further, the operation program 24 and the display data program 25 are required for the number of screens for which data display requests are generated (the same as or less than the number of requested screens for screen display only). In the figure, only one set is shown. When the address on the bus is the first address, the data is not stored in the display data storage memory, and when the address on the bus is the second address, the data on the bus is stored in the display data storage memory. Same as the operation in Figure 1, but there are multiple areas of display data storage memory, and the area where the data on the bus is stored is specified by the data written in the screen specification register by the screen specification command of the display data program. 1 is different from the operation in FIG.

[0007]

As described above, according to the present invention, it is not necessary to add an instruction for displaying data in real time, and the address of the data to be displayed is changed from the first address to the second address. By doing so, the display data can be collected, so that the execution time does not increase even if the data is displayed in real time. As a result, even in a device whose control depends on the execution time, data can be collected in real time without affecting the execution speed, and the maintainability of the device can be improved. Further, in a control system in which display devices such as a plurality of programming panels are connected to a common programmable controller, display data corresponding to a plurality of screens can be displayed simultaneously.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a second embodiment of the present invention.

FIG. 3 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 1 CPU 2 Program memory 3 Data memory 4 Decoder 5 Display data storage memory 6 Control circuit 20, 22, 24 Normal operation program 21, 23, 25 Display data program

Claims (2)

[Claims] 1. When there is a screen display request from the programming panel, a display data program including a command of the operation program is generated separately from the operation program corresponding to the display screen, and the operation corresponding to the display screen is generated. A method for collecting real-time display data in a programmable controller, wherein the display data program is executed instead of the program to display the data in real time on the screen along with the execution of the operation program. A decoder for generating an error in the address signal of the data memory included in the instruction of the program is provided, and the decoder of the data memory included in the instruction of the operation program that does not correspond to the display screen is provided. Address as the first address, and when the empty bit of the address of the data memory included in the instruction of the display data program corresponding to the display screen is flagged to make it the second address, the address on the bus Is a first address, the data is not stored in the display data storage memory, and if the address on the bus is a second address, the data on the bus is stored in the display data storage memory. For collecting real-time display data in Japan. 2. When a plurality of display data programs are required, a screen designation command is provided for each display data program, and when the address on the bus is the second address,
2. The method of collecting real-time display data in a programmable controller according to claim 1, wherein the data on the bus is stored in an area of a display data storage memory corresponding to the screen designation command.