JPH1124965A - Programmable controller - Google Patents

Abstract

(57) [Problem] To provide a PLC in which technical measures are taken to measure an execution time without changing an application program in the PLC. A measurement start address, a measurement end address, an address comparison means of an application program, an interrupt generation means for generating an interrupt signal to a microprocessor based on an interrupt detection signal obtained from the result, and a start of execution measurement A reference clock for measuring the time from the interruption of the measurement to the interruption at the end of measurement, a read-only memory, a random access memory, an external I / O module controlled by a programmable controller, and a console for supporting the development of application programs. One with an external I / F for making connections.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a programmable controller (hereinafter referred to as "PLC") used for process control, and more particularly to a programmable controller for analyzing the execution time.

[0002]

2. Description of the Related Art In the development of PLC application programs, when measuring the execution time of a program that requires high speed, the part to be measured is created in advance as another program, calculated from the execution result, and measured.

[0003]

However, in the above-described means, operating conditions are different from those of an actually used program, and in many cases, results different from reality are obtained. In addition, an operation for creating a program to be measured and preparation for measurement are required, which has been a hindrance to efficient program development. SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to solve the drawbacks by taking technical measures to measure the execution time without changing an application program in a PLC. To provide a PLC.

[0004]

Means for achieving the object are a first address setting means for setting a physical address of a measurement start address of an application program in a programmable controller, and a measurement end address. Second address setting means for setting a physical address of the first address, a first address comparing means for comparing an address line signal of a microprocessor bus with the first address setting means, and detecting that measurement has started. Means, a second address comparing means for comparing the address line signal of the microprocessor bus with the second address setting means, and detecting that the measurement is completed, and an interrupt detection signal obtained from the result. Interrupt generating means for generating an interrupt signal to a microprocessor; A reference clock for measuring the time from the interrupt at the start of measurement to the interrupt at the end of measurement, a counter for counting this reference clock, and a counter for managing the execution of the application program A read-only memory that stores a system program, a random access memory that stores an application program and a system memory necessary for managing execution of the system program, an external I / O module controlled by a programmable controller, and an application program. Equipped with an external I / F for connecting to a console that supports development,
A program execution time between a measurement start address and a measurement end address of an application program arbitrarily set by a program console can be measured in real time.

The operation will be described below. In the PLC to which the present invention is applied, a case where the execution time from the first line to the fifth line is measured based on an example of an application program shown in FIG. First, a user connects a development support console, for example, a personal computer (hereinafter, referred to as a PC) to the PLC, and inputs the line numbers 1 and 5 of the portion of the PC for measuring the execution time of the application program by keying. This allows P
The C execution time measurement program calculates the measurement start physical address of the application program, sets it in the PLC address setting buffer 1, calculates the measurement end physical address of the application program, and sets it in the PLC address setting buffer 2. . Both setting buffers are stored in a random access memory (hereinafter, referred to as RAM), and can be rewritten and changed even during execution of an application program. The MPU in the PLC checks whether or not the contents of the address setting buffer 1 and the address setting buffer 2 have been changed after the application program has finished executing one cycle. The value of the address setting buffer 2 is set in the first address setting means, respectively, in the second address setting means.

Since the MPU in the PLC executes the program from the start address of the application program,
The program code is read from the physical address set in the first address setting means.
A measurement start physical address of the application program is generated as a U bus address line signal, a read signal is generated as a control line signal, and an output signal of the first address comparing means is activated. The interrupt generation means receives the signal and transmits an interrupt signal to the MPU. At this time, an interrupt number at the start of measurement is added as information at this time, and the MP
U suspends execution of the application program,
The processing shifts to the first interrupt program in the system program.

When the program shifts to the first interrupt program, the MPU
After temporarily saving the register currently in use, read the current value from the counter, store the value in the measurement start count buffer in the RAM, return the saved register to the original value, And returns to the application program. When the MPU returns from the first interrupt program, the MPU sequentially reads and executes the application program again, and starts reading from the physical address set in the second address setting means on the fifth line in FIG.
Read the program code of the ND instruction,
U generates the measurement end physical address of the application program in the address line signal of the MPU bus, generates a read signal in the control line signal, and activates the output signal of the second address comparison means. The interrupt generation means receives the above signal and transmits an interrupt signal to the MPU. At this time, the interrupt number 2 at the end of the measurement is added, and the MPU suspends the execution of the application program based on this information. Then, the processing shifts to the interrupt program 2 in the system program.

When the program shifts to the second interrupt program, the MPU
After temporarily saving the register currently in use, read the current value from the counter, store the value in the measurement end count buffer in the RAM, return the saved register to the original value, and then execute interrupt program number 2. And returns to the application program. When the MPU returns from the second interrupt program, the MPU executes the application program again, so that the END instruction on the fifth line in FIG. 2 is executed. When the END instruction is executed, execution of one cycle of the application program is completed, control is transferred from the application program to the system program, and in the system program, in addition to the normal system management program, the interrupt program No. 1 and the interrupt program The difference calculation is performed between the measurement start count buffer and the measurement end count buffer stored in No. 2.

The difference calculation value is a value obtained by counting the reference clock from before the start of execution of the first line to before the start of execution of the fifth line of the application program in FIG.
By multiplying by the cycle of the reference clock, it is possible to convert to the execution time of the first to fifth lines. After the end of the conversion operation to the execution time in the system program, the MPU again executes
Since the execution of the program is repeated from the line, the execution time from the first line to the fifth line of the application program can be measured in real time.
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an overall configuration diagram of a programmable controller CPU showing an embodiment of the present invention, and FIGS. 2A, 2B and 2C show an example of an application program. (a) shows the execution contents, (b) shows the operation contents, and (c) shows the meaning of the symbol. FIG. 3 is a memory map in a random access memory, FIG. 4 is a flowchart of a system program and an interrupt program showing one embodiment of the present invention, and FIG. 5 is a timing chart showing one embodiment of the present invention. In FIG. 1, a first address setting means 11 for setting a physical address of a measurement start address of an MPU and an application program
And the first address setting means 11 for comparing the address line signal of the MPU bus with the first address setting means 11, reading the program code from the measurement start address of the application program, and detecting the start of measurement. Address setting means 21 for setting the physical address of the measurement end address of the application program;
The second address comparing means 22 for reading the program code from the measurement end address of the application program and detecting the end of the measurement, the output result of the first address comparing means, And M from the output result of the second address comparing means.
The interrupt generation means 7 for generating an interrupt in the PU and the reference clock 8 are sequentially counted, and the MPU reads the count value of the reference clock 8 when an interrupt occurs in the MPU, thereby measuring the application program. It measures the execution time from the start physical address to the measurement end physical address. 1 is a microprocessor, 2 is a read-only memory, 3 is a random access memory, 4 is a counter, 5 is an external I / F, and 6 is a microprocessor bus.

2 (a), 2 (b) and 2 (c), the application programs created as shown in FIG. 2 (a) correspond to line numbers 1 to 4 and d = a * b + c, as shown in FIG. 2 (b).
The content of the operation for calculating h = e / f-g is described in a functional block diagram language expressed by the graphic expression shown in FIG.
This application program is downloaded by the PC to the memory map diagram application program area of FIG. 3 inside the RAM in the PLC. Each operation code to be downloaded is a machine language that can be executed by the MPU in the PLC. After the download is completed, the MPU sequentially reads the machine language from a head address and executes each instruction. The codes a to h attached to the instruction codes in the application program area of FIG. 3 are register names used for the operation. This embodiment describes a case where the execution time from the start address of an application program to the address of an end instruction is measured.

The PC is connected to the PLC, and when measuring the execution time of the application program of FIG.
The execution time measurement program of the PC is started, and lines 1 and 5 which are the execution time measurement range of the application program are set. As a result, the PC sets the measurement start address of line 1 of the application program in FIG.
Is calculated from the application program area of
It is assumed that the address 000 (H) ”has been obtained. Next, when the measurement end address of the line 5 is obtained, the address of the END” instruction code of the line 5 is calculated from the application program area of FIG. "It is assumed that the address has been obtained. The PC stores the two measured physical address values of the measurement start address and the measurement end address in the RAM in the PLC.
Start_ADR ”31 and“ END_ADR ”32. Subsequently, the setting change flag“ SET_ADR ”
Write 1 to FLG "33.

Next, a description will be given with reference to FIGS. After the power is turned on, an initialization process is performed, the first address setting means 11 and the second address setting means 21 are cleared to 0, and thereafter, each time the application program is executed for one cycle, the "SET_FLG" 33 becomes 1. If “1” is written from the console, the “START_ADR” 31 and “END_ADR” 3
2 is recognized as a change command.

If this command is recognized, "S"
Check the validity of TART_ADR "31" and "END_ADR" 32, and if there is no abnormality, "START_AD"
R "31 to the first address setting means 11," E
ND_ADR ”32 is stored in the second address setting means 2
Each is set to 1 and “SET_FLG” 33 is cleared to 0. "START_ADR" 31 value of 12000
(H) and the value of “END_ADR” 32 12076
When (H) is determined to be appropriate, the set value for the first address setting means 11 is 12000 (H), and the set value for the second setting means 21 is 12076 (H). When the MPU reads the "LOAD a" 34 instruction of the RAM in order to execute the instruction at the address 12000 (H), the address line signal of the MPU bus becomes 12000 (H).
(H), a read signal is generated as the control line signal,
The output of the first address comparison means 12 is activated and the MPU
, An interrupt 1 is generated by the interrupt generating means 7.

When an interrupt 1 occurs, after the register is saved in the interrupt program, the current integrated count value is read from the counter and written into "CNT1" 36 in the RAM, and 1 is written into "INT_FLG" 38, and then the register is written. Is returned to the original value and the interrupt program ends. When the program of interrupt 1 is completed, “LOAD”
a) The execution of the 34 instructions is started, and thereafter the application program is sequentially executed.
At the time when the ND "35 instruction is executed, the output of the address comparison means 2 is activated to generate a read signal at address 1076 (H) from the MPU bus, and the interrupt generation means 7 generates an interrupt 2 in the MPU.

When interrupt 2 occurs, after the register is saved in the interrupt program, the current integrated count value is read from the counter, written into "CNT2" 37 in the RAM, and 2 is written if "INT_FLG" 38 is 1. Thereafter, the register is returned to the original value, and the interrupt program ends. When the program of interrupt 2 is completed, "E"
ND "35 instruction is executed, which ends one cycle of the application program.
Means return to the system program. In the system program, each time one cycle of the application program is completed, "INT_FLG" 38 in the RAM
Is checked to be 2, and if it is 2, the difference value CNT2-CNT1 of the values of "CNT1" 36 and "CNT2" 37 written in the interrupt programs 1 and 2 is calculated. By doing, interrupt 1
The number of pulses of the reference clock between the interrupts 2 is obtained.
a It is the execution time from the "34" instruction to the "END" 35 instruction.

After this calculation processing, by clearing "INT FLG" 38, it becomes possible to repeatedly measure the execution time. The calculation result of CNT2-CNT1 is "CNT"
By writing the information in 39, the PC can refer to the screen at an arbitrary time, and the real-time display can be repeatedly performed on the screen of the PC. In FIG. 5, C
NT11, CNT12, and CNT13 are integrated count values in the interrupt 1; CNT21, CNT22, and CNT23 are integrated count values in the interrupt 2; .

[0018]

As described above, according to the present invention, the execution time of an arbitrary part of an application program can be measured in real time without changing the application program at all. It is possible to provide a powerful means, and is extremely useful in practical use.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing the inside of a programmable controller CPU according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of an application program.

FIG. 3 is a memory map diagram in a random access memory.

FIG. 4 is a flowchart of a system program and an interrupt program showing one embodiment of the present invention.

FIG. 5 is a timing chart of an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Microprocessor 2 Read-only memory 3 Random access memory 4 Counter 5 External I / F 6 Microprocessor bus 7 Interrupt generating means 8 Reference clock 11 First address setting means 12 First address comparing means 21 Second address setting Means 22 Second address comparing means 31 Address setting buffer 1 32 Address setting buffer 2 33 Setting change flag 34 "LOAD a" instruction code 35 "END" instruction code 36 Counter reading value at measurement start 37 Counter reading value at measurement end 38 Interrupt flag 39 Application program execution clock count value

Claims (1)

[Claims] 1. A programmable controller, comprising:
First address setting means for setting a physical address of a measurement start address of the application program;
Second for setting the physical address of the measurement end address
Address setting means, a first address comparing means for comparing the address line signal of the microprocessor bus with the first address setting means, and detecting that the measurement has started, and an address line signal of the microprocessor bus. A second address comparing means for comparing the second address setting means with the second address setting means and detecting that the measurement has been completed;
Interrupt generating means for generating an interrupt signal to the microprocessor based on the interrupt detection signal obtained from the result, and the time from the interrupt at the start of the execution measurement of the application program to the interrupt at the end of the measurement. A reference clock for measuring, a counter for counting this reference clock, a read-only memory storing a system program for managing the execution of the application program, and a management for executing the application program and the system program A program console comprising: a random access memory for storing a required system memory; and an external I / F for connecting an external I / O module controlled by a programmable controller and a console for supporting the development of an application program. Programmable controller configured to program execution time between measurement start address and the measurement end address of the application program can be measured in real time to be more freely set.