JP3661732B2 - Programmable controller - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a programmable controller, and more particularly to a programmable controller capable of measuring a scan time distribution of an application program.
[0002]
[Prior art]
A conventional programmable controller executes data collection from a sensor, device control, and the like based on an application program stored in advance.
[0003]
As a program execution method, there is a scan method in which an application program stored in advance is continuously executed many times.
[0004]
For example, by continuously executing an application program that collects a pressure signal and a temperature signal from a sensor or the like, and compensates and outputs the pressure signal with the temperature signal, the temperature signal from the programmable controller is periodically received. Will be output.
[0005]
However, in general, the time required to execute an application program once by a programmable controller (hereinafter referred to as scan time) is not always constant and varies depending on conditions at the time of execution of the program.
[0006]
For example, depending on various conditions such as the input pressure signal and the temperature signal value variation, the temperature compensation calculation content, etc., all the instructions of the application program are not executed but skipped instead of being executed, Or, an instruction that is executed many times occurs, so that the scan time always varies.
[0007]
In particular, when a short scan time is required, it is necessary to devise measures to shorten the scan time when creating the application program. In this case, it is necessary to obtain information on the scan time of the application program executed by the programmable controller. There is.
[0008]
In general, some programmable controllers have such functions added, and FIG. 5 is a block diagram showing an example of such a conventional programmable controller.
[0009]
In FIG. 5, 1 is an input / output circuit, 2 is a control circuit, 3 is a memory circuit in which an application program is stored, 4 is a debug circuit, 100 is an input signal, and 101 is an output signal.
[0010]
The input signal 100 is input to the control circuit 2 via the input / output circuit 1, and the output from the control circuit 1 is output to the outside as the output signal 101 via the input / output circuit 1. The control circuit 2 is connected to the memory circuit 3 and the debug circuit 4.
[0011]
Here, the operation of the conventional example shown in FIG. 5 will be described. The control circuit 2 sequentially reads and executes the instructions of the application program stored in the storage circuit 3 in advance.
[0012]
On the other hand, the debug circuit 4 measures information related to the scan time required to execute the application program once.
[0013]
Specifically, the debug circuit 4 measures and stores the latest scan time, the maximum and minimum values of the scan time, and the average scan time.
[0014]
FIG. 6 is a block diagram showing a specific example of the debug circuit 4. In FIG. 6, 5 is a counter circuit for time measurement, 6 is a control circuit, 7 is a storage circuit, and 102 is a clock signal.
[0015]
The clock signal 102 is input to the time measurement counter circuit 5, and the output of the time measurement counter circuit 5 is connected to the control circuit 6. Further, the control circuit 6 and the memory circuit 7 are connected to each other.
[0016]
Here, the operation of the debug circuit 4 shown in FIG. 6 will be described with reference to FIG. FIG. 7 is a flowchart for explaining the operation of the debug circuit 4.
[0017]
In FIG. 7A, the control circuit 6 resets the time measuring counter circuit 5 and starts the counting operation, and detects the end of execution of the application program in FIG. 7B.
[0018]
When the end of the application program is detected in FIG. 7B, the control circuit 6 reads the count value of the time measurement counter circuit 5 in FIG. 7C, and the storage circuit 7 as the latest scan time in FIG. 7D. To store.
[0019]
In FIG. 7E, the control circuit 6 calculates the average scan time and stores the result in the storage circuit 7.
[0020]
In FIG. 7 (f), the control circuit 6 determines whether or not the count value is larger than the maximum value of the scan time up to the previous time.
[0021]
If the count value is larger than the maximum value up to the previous time, the control circuit 6 stores the count value in the storage circuit 7 as the maximum value in FIG. 7G and performs the process of FIG.
[0022]
Similarly, in FIG. 7H, the control circuit 6 compares the count value with the minimum value of the scan time up to the previous time to determine whether or not it is small.
[0023]
If the count value is smaller than the previous minimum value, the control circuit 6 stores the count value as the minimum value in the storage circuit 7 in FIG. 7 (i) and performs the process of FIG. 7 (j).
[0024]
Finally, in FIG. 7 (j), the control circuit 6 determines whether or not the measurement of the scan time or the like is finished. If it is a remeasurement, the process returns to the process of FIG. 7 (a), and if the measurement is finished, the process is finished. .
[0025]
In addition, it is possible to connect a programmable controller and an application program development tool, read information on the scan time measured by the debug circuit 4 with this application program development tool, and display the information on a display screen or the like.
[0026]
In general, it is devised to shorten the scan time by monitoring the information while executing the application program with a programmable controller.
[0027]
As a result, the debug circuit 4 can obtain information relating to the scan time necessary for creating the application program of the programmable controller.
[0028]
[Problems to be solved by the invention]
However, in the conventional example shown in FIG. 5 and the like, although individual information such as the maximum value and minimum value of the scan time is known, for example, whether the maximum value of the scan time has occurred suddenly or has occurred constantly. Cannot be distinguished.
[0029]
For this reason, there is a problem that it is not known which part of the application program should be corrected, and the efficiency of the correction work of the application program is deteriorated.
Therefore, the problem to be solved by the present invention is to realize a programmable controller capable of obtaining the distribution state of the scan time length.
[0030]
[Means for Solving the Problems]
In order to achieve such a problem, in the first aspect of the present invention,
In the programmable controller,
An input / output circuit;
A storage circuit for storing application programs;
A control circuit for controlling the input / output circuit and the memory circuit;
Time measurement counter circuit for measuring the time for which the application program is executed once, a plurality of distribution counting counter circuits provided corresponding to a preset time range, and measurement of the time measurement counter circuit A debugging circuit comprising a control circuit for determining which time range of the preset time range corresponds to the time and incrementing a count value of the corresponding distribution counting counter circuit; It is a characteristic.
[0031]
In order to achieve such a problem, in the second aspect of the present invention,
In the programmable controller,
An input / output circuit;
A storage circuit for storing application programs;
A time measuring counter circuit for measuring a time for which the application program is executed once;
A plurality of distribution counting counter circuits provided corresponding to a preset time range;
The distribution counting counter circuit which controls the input / output circuit and the storage circuit and determines which time range of the preset time range corresponds to the measurement time of the time measurement counter circuit. And a control circuit for incrementing the count value.
[0032]
In order to achieve such a problem, in the third aspect of the present invention,
In the first and second aspects of the present invention,
The connected application program development tool displays a distribution diagram of time for which the application program is executed once based on the count value counted by the distribution counting counter circuit.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment of a programmable controller according to the present invention.
[0035]
In FIG. 1, 1, 2 and 3 are given the same reference numerals as in FIG. 5, 4a is a debug circuit, 100a is an input signal, and 101a is an output signal.
[0036]
The input signal 100a is input to the control circuit 2 via the input / output circuit 1, and the output from the control circuit 1 is output to the outside as the output signal 101a via the input / output circuit 1. The control circuit 2 is connected to the memory circuit 3 and the debug circuit 4a.
[0037]
Here, the operation of the embodiment shown in FIG. 1 will be described. The control circuit 2 sequentially reads and executes the instructions of the application program stored in the storage circuit 3 in advance.
[0038]
On the other hand, the debug circuit 4a measures information related to the scan time required to execute the application program once.
[0039]
Specifically, the debug circuit 4a measures the scan time, determines which time range corresponds to a preset time range, and counts the number. In other words, the distribution status in the scan time range is measured and stored.
[0040]
2 is a block diagram showing a specific example of the debug circuit 4a. In FIG. 2, reference numerals 5 and 102 are assigned the same reference numerals as in FIG. 6, 6a is a control circuit, 8, 9, 10 and 11 are It is a counter circuit for distribution counting.
[0041]
The clock signal 102 is input to the time measurement counter circuit 5, and the output of the time measurement counter circuit 5 is connected to the control circuit 6a. The control circuit 6a and the distribution counting counter circuits 8, 9, 10 and 11 are connected to each other.
[0042]
Here, the operation of the debug circuit 4a shown in FIG. 2 will be described with reference to FIG. FIG. 3 is a flowchart for explaining the operation of the debug circuit 4a.
[0043]
In FIG. 3A, the control circuit 6a presets a time range for counting by the distribution counter circuit 8-11.
[0044]
Specifically, when the measured scan time is “Tscan”,
t3 ≦ Tscan <t4 (1)
t2 ≦ Tscan <t3 (2)
t1 ≦ Tscan <t2 (3)
0 ≦ Tscan <t1 (4)
(However, 0 <t1 <t2 <t3 <t4)
If the condition of the expression (1) is satisfied, the count value of the distribution counting counter 8 is incremented. Similarly, if the conditions of the expressions (2), (3), and (4) are satisfied, the distribution counting counters 9 and 10 are satisfied. And 11 are incremented.
[0045]
In FIG. 3B, the control circuit 6a resets the time measuring counter circuit 5 and starts the counting operation, and detects the end of execution of the application program in FIG. 3C.
[0046]
When the end of the application program is detected in FIG. 3 (c), the control circuit 6a reads the count value of the time measuring counter circuit 5 in FIG. 3 (d).
[0047]
In FIG. 3E, the control circuit 6a determines whether or not the count value satisfies the condition of the expression (1).
[0048]
If the condition of Expression (1) is satisfied, the control circuit 6a increments the count value of the distribution counting counter circuit 8 in FIG. 3F, and performs the processing of FIG.
[0049]
In FIG. 3G, the control circuit 6a determines whether or not the count value satisfies the condition of the expression (2).
[0050]
If the condition of the expression (2) is satisfied, the control circuit 6a in FIG. 3 (h) increments the count value of the distribution counting counter circuit 9, and performs the processing of FIG. 3 (l).
[0051]
Further, in FIG. 3 (i), the control circuit 6a determines whether or not the count value satisfies the condition of Expression (3).
[0052]
If the condition of Expression (3) is satisfied, the control circuit 6a in FIG. 3 (j) increments the count value of the distribution counting counter circuit 10 and performs the process of FIG. 3 (l).
[0053]
In FIG. 3K, the control circuit 6a increments the count value of the distribution counting counter circuit 11.
[0054]
Finally, in FIG. 3 (l), the control circuit 6a determines whether or not the measurement is finished. If the measurement is re-measured, the process returns to the process of FIG. 3 (b), and if the measurement is finished, the process is finished.
[0055]
FIG. 4 is a distribution diagram showing an example of the scan time distribution state measured by the debug circuit 4a.
[0056]
Specifically, a programmable controller and an application program development tool are connected, and information on the scan time distribution measured by the debug circuit 4a is read out by this application program development tool and displayed on a display screen or the like in a distribution diagram. Is.
[0057]
In FIG. 4, “i”, “b”, “c” and “d” are the count values counted by the distribution counting counter circuits 11, 10, 9 and 8, and in FIG. It can be seen that there are many distributions in the time range shown in FIG.
[0058]
In addition, since the distribution of “d” in FIG. 4 is small, it can be recognized that the maximum value of the scan time is suddenly generated.
[0059]
For this reason, in the above-mentioned case, it can be specified that there is a problem in a specific branch routine or the like that is not normally executed in the application program, and it is sufficient to correct that portion, so that the efficiency of the application program correction work is improved.
[0060]
On the other hand, if the count value of the portion “d” in FIG. 4 is large, it can be recognized that the maximum value of the scan time occurs constantly, so there is a problem with the routine that is routinely executed in the application program. It can be specified that there is.
[0061]
As a result, the debug circuit 4a determines the length of the scan time, determines which time range corresponds to a preset time range, and counts the number of the scan time lengths. It becomes possible to obtain the distribution situation.
[0062]
In the debug circuit 4a of FIG. 2, four distribution counting counter circuits are illustrated for simplicity of explanation, but of course, the number is not limited to this number, and by providing a large number of distribution counting counter circuits. More detailed distribution status of scan time can be obtained.
[0063]
Further, in the debug circuit 4a of FIG. 2, the control circuit 6a is illustrated separately from the control circuit 2 in FIG. 1 for the sake of simplicity of explanation. Absent.
[0064]
In general, a control device such as a personal computer or a workstation is used as an application program development tool.
[0065]
In addition, regarding the identification of a phenomenon that occurs only when the scan time exceeds a certain time, it is necessary to investigate the relationship between the frequency at which the scan time exceeds the certain time and the occurrence frequency of the phenomenon. According to the above, it becomes possible to examine these relationships.
[0066]
【The invention's effect】
As is apparent from the above description, the present invention has the following effects.
The debug circuit determines the scan time length, determines which time range corresponds to a preset time range, and counts the number of the time ranges, thereby obtaining the scan time length distribution state. It is possible to realize a programmable controller.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an embodiment of a programmable controller according to the present invention.
FIG. 2 is a configuration block diagram showing a specific example of a debug circuit.
FIG. 3 is a flowchart illustrating an operation of a debug circuit.
FIG. 4 is a distribution diagram showing an example of scan time distribution;
FIG. 5 is a block diagram showing an example of a conventional programmable controller.
FIG. 6 is a configuration block diagram showing a specific example of a debug circuit.
FIG. 7 is a flowchart for explaining the operation of the debug circuit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Input / output circuit 2, 6, 6a Control circuit 3, 7 Memory circuit 4, 4a Debug circuit 5 Time measurement counter circuit 8, 9, 10, 11 Distribution counter circuit 100, 100a Input signal 101, 101a Output signal 102 Clock signal

Claims (3)

In the programmable controller,
An input / output circuit;
A storage circuit for storing application programs;
A control circuit for controlling the input / output circuit and the memory circuit;
Time measurement counter circuit for measuring the time for which the application program is executed once, a plurality of distribution counting counter circuits provided corresponding to a preset time range, and measurement of the time measurement counter circuit A debug circuit comprising: a control circuit that determines which time range of the preset time range falls and increments the count value of the corresponding distribution counting counter circuit;
A programmable controller characterized by comprising: In the programmable controller,
  An input / output circuit;
  A storage circuit for storing application programs;
  A time measuring counter circuit for measuring a time for which the application program is executed once;
  A plurality of distribution counting counter circuits provided corresponding to a preset time range;
  The distribution counting counter circuit which controls the input / output circuit and the storage circuit and determines which time range of the preset time range corresponds to the measurement time of the time measurement counter circuit. A control circuit for incrementing the count value of
A programmable controller characterized by comprising: A connected application program development tool displays a distribution map of time when the application program is executed once based on the count value counted by the distribution counting counter circuit.
The programmable controller according to claim 1 and claim 2.

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