JPH02253305A - Signal tracing system for programmable controller - Google Patents

Abstract

PURPOSE:To display the signal changing states for each ladder sequence in response to the display requests by designating the signals to be displayed for each ladder sequence and storing these signals into a signal store memory. CONSTITUTION:The ladder sequence, etc., are displayed on a display screen 11 of a program preparing device 10, and the designation of a coil, the change of a display cycle, etc., are carried out in the ladder sequence with use of the operation keys 14. A processor 21 controls totally a programmable controller PC 20, and the signals including the input, output, auxiliary relay, internal register signals, etc., which are necessary for trace are stored in an area of a signal store memory 41 of a RAM 40. Thus the signals to be checked are stored in the memory 41 for each ladder sequence and therefore the trace result can be displayed on a ladder sequence diagram. As a result, the signal changing states can be simply recognized and a sequence program is easily debugged.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a PC (programmable controller) signal tracing method, and particularly to a PC signal tracing method that displays the changing state of a PC signal controlled by a ladder sequence. Regarding the method.

[Prior Art] In order to check whether a created sequence program has been created correctly, a PC checks whether a specific signal is being processed normally. Furthermore, when the PC does not operate normally, it is necessary to examine the state of change in a specific signal in order to investigate the cause.

These signals are displayed on a display device of a numerical control unit (CNC) coupled to a PCl or a PC, but if the signals change rapidly or occur infrequently, the display device alone cannot adequately handle the situation. Therefore, it becomes necessary to store a specific signal in memory and reproduce it. In particular, this is because dynamic states, that is, processes of change, are often more important than static states.

As a method of knowing such a state, a method has been adopted in which the program of the control device is changed and a specific signal is monitored. However, if the program of the control device is stored in the ROM, the program itself cannot be changed, so changes in the signal cannot be known.

Further, as a method for monitoring the state of a signal, a method is known in which predetermined signals are sequentially stored in a memory for a certain period of time. This method of tracing the signal state, storing it in another memory, and reproducing it is called tracing. As a way to reproduce this, when running the sequence program,
Some devices print out a list of read addresses, instruction execution step numbers, and signal states on an externally connected printer or the like. However, this method simply traces the signal and stores it in memory, which poses a problem in that the memory capacity becomes enormous.

Therefore, as a trace control method for reducing the memory capacity, there is a method described in Japanese Patent Laid-Open No. 62-243008. This method captures changes in the signal to be traced and traces the same byte or word as the signal.

[Problem to be solved by the invention]

However, with the conventional tracing method, it is possible to see the state of change in a signal at each instruction step, but as the number of steps in a sequence program increases, it becomes extremely difficult to find the required signal and examine its change. Further, since this signal is only a trace of each signal that is considered to be related to the ladder sequence, it is necessary to analyze it by comparing it with the ladder sequence, which is troublesome.

On the other hand, when debugging ladder sequence programs or maintaining equipment, you may want to know how the signal to be traced has changed in relation to other signals, or the temporal relation to the signal that is the cause. many. Therefore, changes in the signal to be traced alone were not sufficient.

The present invention has been made in view of these points, and it is an object of the present invention to provide a PC signal tracing method that can display the changing state of a specific signal for each ladder sequence.

[Means to solve the problem]

In order to solve the above problems, the present invention specifies signals to be displayed in ladder sequence units in a PC signal tracing method for investigating changes in specific signals in a PC (programmable controller), and storing said signals of a sequence in a signal storage memory;
A signal tracing method for a PC is provided, characterized in that the changing state of the signal is displayed on a ladder sequence in response to a display request.

[Effect]

By specifying a ladder sequence on the screen, signals related to that ladder sequence can be traced. Furthermore, since the trace results are displayed on a ladder sequence, it is easy to understand how the signal changes.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 2 is a diagram showing a screen displaying a ladder sequence. In FIG. 0, a display screen 1 is a screen of a program editing device, and a part of a ladder sequence is displayed.

Move the cursor 3 over the coil (Yo, 0) on the display screen 1, and use the operation keys (not shown) to
O, O). Then, tracing is performed on the ladder sequence related to the coil (YO, O) surrounded by the dotted line frame 2.

This tracing is done in the same way as before, by capturing changes in the signal to be traced and
Trace the word.

FIG. 1 is a diagram showing a screen displaying trace results on a ladder sequence according to an embodiment of the present invention.

In the figure, the contacts that are turned on among the contacts are displayed with thick lines. That is, in this figure, there are five contact points (Xo.

0), (Xo, 1), (Y2.O), (X15°0) and (X7.0) are turned on. And the contact (
By turning on Xo, 1), (Y2.O), and (X15.0), the line connected to the coil (YO, O) also changes to a thick line. Therefore, it can be easily determined which contact turns on the coils (YO, O). Then, by operating the operation keys, the status of the next cycle can be displayed.

Although FIG. 1 shows the ladder sequence related to the coil (YO, O), it is also possible to simultaneously trace and display the ladder sequence related to the coil (Yo, 1) as shown in FIG. In this case, use the operation keys to select the coil (
YO, o) & coil (Yo, 1) may be specified at the same time.

FIG. 3 shows a hardware block diagram of a program creation device and a PC (programmable controller) for implementing the present invention. The program creation device 10 is a device that creates a ladder sequence program. As the display screen 11, a CRT, liquid crystal display, or the like is used. On the display screen 11, a display screen 1 such as a ladder sequence shown in FIGS. 1 and 2 is displayed. The function key 13 is a key for commanding functions such as deletion, copying, and modification, and the operation key 14 is a key for performing various operations, such as specifying a coil on a ladder sequence and changing the cycle to be displayed. That's the key.

The program creation device 10 has a microprocessor configuration, and the display processing as described above is processed by the microprocessor within the program creation device 10.

A processor 21 controls the entire PC (programmable controller) 20. The input circuit 22 receives a signal from the outside, converts the signal level, and transfers the signal to the bus. The output circuit 23 outputs an internal output signal to the outside.

The interface 24 for the program creation device is the PC2
This is an interface circuit for connecting the bus No. 0 and the program creation device 1o.

The ROM 30 stores therein a management program 31 that manages the execution of ladder programs, a ladder program 32 that is a sequence program written in a ladder language for controlling machine tools, etc., and the like. The RAM 40 has an area for a signal storage memory 41, and various other data are stored therein, and signals necessary for tracing such as input signals, output signals, auxiliary relay signals, and internal register signals are stored here. Non-volatile memory 50 is connected to the bus.

In the above explanation, the display of the signal was explained by displaying it on the display screen 11 of the automatic program creation device IO, but
If the (programmable controller) has a built-in display device, it is also possible to display the information on that display device.

〔Effect of the invention〕

As explained above, in the present invention, the signals to be investigated are stored in the signal storage memory in units of ladder sequences, and the trace results are displayed on the ladder sequence diagram, so that the changing state of the signal can be easily recognized. , it becomes easier to depack sequence programs.

[Brief explanation of drawings]

Fig. 1 is a diagram showing a screen displaying trace results on a ladder sequence according to an embodiment of the present invention, Fig. 2 is a diagram showing a screen displaying a ladder sequence, and Fig. 3 is a diagram showing a screen displaying trace results on a ladder sequence. It is a block diagram of the hardware of a program creation device and a PC (programmable controller). 1------------・--・Display screen 10--・-・-
...-Automatic program creation device 1-----
−・−・Display screen 3・・・−１−−・−−−１−−
-Function key 4 -------・Operation key O・・----1-・・・・・PC (programmer bluer) 1・−・−・・・−・・−・・−・Processor 2...
・−・・・−・・・−・−・Input circuit 3・・・・−・・
−1−−−−Output circuit 4−・−−−−−・−・−−−−
−・Interface 0−・−111・・−・・−ROM O−・・−−1−−−・・−RAM 1−・・・・−−1−−・−−−1−・Signal Storage memory O
−・・−・−・−−−−1 Non-volatile memory controller applicant FANUC Co., Ltd. agent Patent attorney Takeshi Hattori

Claims (2)

[Claims] (1) In the PC signal tracing method for investigating changes in specific signals in a PC (programmable controller), the signals to be displayed are specified in ladder sequence units, and the signals of the specified ladder sequence are stored in the signal storage memory. A signal tracing system for a PC, characterized in that the signal is stored in a PC, and the changing state of the signal is displayed in a ladder sequence on a display screen in response to a display request. (2) The PC signal tracing method according to claim 1, wherein the ladder sequence unit is specified by selecting a coil of the ladder sequence on the display screen with a cursor.