JPS6186806A - Digital control arithmetic system - Google Patents

Abstract

PURPOSE:To improve the efficiency of a sampling action by changing the definition and the time needed for an operation at every time the contents of the operation are changed and calculating the total operation time of a changed operation to decide a new sampling cycle. CONSTITUTION:An operation executing means 2 executes repetitively a prescribed operation defined by an operation defining means 5 at every time an interruption is applied from a sampling command means 1 in a prescribed sampling cycle. When the operation defined by the means 5 is changed by an operation change command means 4, the time needed for operation which is stored in a memory means 3 is also changed. Then a sampling cycle calculating means 6 decides the new sampling cycle based on the total operation time of the changed operation. This new sampling cycle is informed to the sampling command means 1. In such a way, an operation is always carried out in an optimum sampling cycle despite the change of the operation.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to a digital control calculation system with a variable sampling period.

(B) Prior Art In general, it is more efficient and desirable for the sampling period to be shorter within the range in which calculations can be executed. Therefore,
In a digitally controlled arithmetic unit with a variable sampling period, each time the content of calculations or the number of calculations changes, the shortest sampling period must be found and manually reset, which is very time-consuming and troublesome.

(C) Purpose The purpose of this invention is to eliminate the trouble of resetting the sampling period each time in response to changes in the number of operations, contents of operations, etc.
It is an object of the present invention to provide a digital control calculation method that can always perform efficient sampling.

(D) Configuration In order to achieve the above object, the digital control calculation method of the present invention includes a sampling command means 1 which outputs a sampling command of a predetermined period, and a plurality of calculations programmed in advance, as shown in FIG. , a calculation execution means 2 for starting and executing a series of calculations by the sampling command, a storage means 3 for storing the type of calculation and the required time for the calculation, and a calculation change command means 4 for outputting a calculation change command. , is started by this operation change command, and changes the definition and
The calculation definition changing means 5 changes the required time, etc. When the definition and required time of the calculation are changed, the total calculation time of the changed calculation is calculated, and the new calculation time is calculated based on this total calculation time. a sampling period calculation means 6 for calculating a sampling period; when there is no definition or change of the calculation, the period of the sampling command of the sampling command means 1 is left as is; when there is a definition or change of the calculation, The series of calculations is executed using the calculated period of the sampling command as a new period.

(e) Examples Hereinafter, this invention will be explained in more detail with reference to Examples.

FIG. 2 shows an example of a program execution time chart according to the embodiment of the present invention. Here, two programs having priority are executed under the control program, namely, an arithmetic execution program (which has priority) and an arithmetic definition program.

The calculation execution program is started by an interruption caused by a sampling command, and the calculation definition program is started by an interruption caused by a calculation change command. .

If a sampling command is entered during execution of the control program, an interrupt is generated and the program shifts to the calculation execution program. The processing operations in the calculation execution program are
This will be explained with reference to the figures.

First, when an interrupt is generated by a sampling command and the calculation execution program is started, the steering knob S'T1
1, the type of calculation to be processed first and the constants used in the calculation are read from the data table, and preprocessing is performed (Ste Nobu 5T2).

The data table is as shown in Figure 6, from 1st to n
, up to the Nth data table is provided, and each table has the type of operation (1,..., m
, M calculation subroutines N11), constants, etc. are stored, respectively. For example, in data table 1,
The type of operation of operation function 2 and constants 2-1, 2-2, . . . are stored.

In step ST2, data is read from this data table corresponding to n. Therefore, in the first step where n=1, the calculation unit 2 and its related constants are read out from the data table l.

Next, the process moves to step ST3, and it is determined whether m=0, that is, whether the calculation subroutine seed of data table n is not 0. If it is not O, then the process moves to step ST4, and a calculation subroutine m is executed. Since 1.2, . . . m, .

The calculation results obtained by the execution are written into a predetermined area of the storage section. Thereafter, +1 is added to the contents of n (step 5T5), and it is determined in step ST6 whether n has reached N. If n has not reached N, the process returns to step ST2. Since n=2 at step ST5, the type of operation and its data are then read from the second data table, and the corresponding operation subroutine is executed in the same manner as described above.

Note that if m = O in step ST3, the process in step ST4 is skipped. In the above manner, n
The process from step ST2 to step ST6 is repeated by sequentially incrementing n until it reaches N.

In this case, the time required for the calculation of the calculation subroutine varies depending on the routine. Each calculation subroutine 1.2,
. . . m . . . The required time for M is stored in the calculation time chill pull.

An example is shown in FIG.

When the processing from step ST2 to step ST6 is repeated N times, the determination in step ST6 becomes YES,
The operation of the calculation execution program ends and returns to the control program. Then, it waits for the next interrupt.

Thereafter, every time a sampling command is input, the calculation execution program shown in FIG. 3 is activated, and the same operation as described above is repeated. The period t1 of this sampling command is repeated at the same period t1 unless the calculation is defined or changed. This sampling period t1 is the shortest in consideration of the total time required for each calculation subroutine stored in data table 1 to data table N of the calculation execution program and some time required for determination in step ST6 etc. shown in FIG. will be selected at the time of

When the content of the calculation is to be defined or changed, a calculation change command is input, and the calculation definition program shown in FIG. 4 is activated.

If a computation change command is input during execution of the computation execution program, the computation execution program has priority over the computation definition program, so the computation definition program is entered upon completion of the computation execution program.

'1M! - When the definition program is entered, the changed contents of the data table are read, and a new sampling period t2 is calculated from the processing time necessary for judgment in addition to the time stored in the calculation required time table shown in FIG. At this point, neither the data in the table nor the sampling period has been changed yet.

Next, in step 5T13, the sampling period t up to the previous time is
1 and the newly calculated sampling period t2. If tl>t2, first write the new data to be changed to the data table (step 5T1).
4) Next, the sampling period is changed from tl to t2 (step 5T15).

Also, in step 5T13, if t1≦t2, first change the sampling period from tl to t2, step 5T1
6), then write the changed data to the data table (step 5T17).

The newly calculated sampling period t2 is tl
If it is larger than , the sampling period is changed first. This is to prevent the calculation time from exceeding the sampling period even if a sampling command comes in the middle of the execution of the calculation program and the calculation execution program with a high priority is interrupted.

In the example shown in Figure 2, a sampling command was input manually during the execution of a calculation setting program started by a calculation change command, so the calculation definition program was interrupted, moved to the calculation execution program, and then restarted the calculation definition program. In other words, the calculation definition program is processed in two parts.

(f) Effects According to the digital control calculation method of this invention, when the number of calculations or calculation contents is changed, the corresponding sampling period is calculated accordingly and the sampling period is switched to that sampling period, so the shortest sampling is always possible. A cycle can be obtained and efficient processing can be performed.

In addition, when the calculation contents are changed, a calculation change command is issued, and the sampling period is automatically calculated and switched. This has the advantage of saving you the trouble of entering the settings.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of the present invention, and FIG.
The figure is a program execution time chart of one embodiment of the present invention, Figure 3 is a diagram showing the processing flow of the calculation execution program, Figure 4 is a diagram showing the processing flow of the calculation definition program, and Figure 5 is a diagram showing the processing flow of the calculation execution program. FIG. 6 is a diagram showing an example of the required time table of the calculation subroutine used in the above embodiment, and FIG. 6 is a diagram showing an example of each data table used in the above embodiment. l: Sampling old means, 2: Calculation execution means, 3: Storage means, 4: Calculation change command means, 5: Calculation definition means, 6: Sampling period calculation means

Claims (1)

[Claims] (1) Sampling command means that outputs a sampling command at a predetermined period, a calculation execution means in which a plurality of calculations are programmed in advance and a series of calculations is started and executed by the sampling command, and the types and calculations of the calculations. a storage means for storing the required time; a calculation change command means for outputting a calculation change command; a calculation definition means activated by the calculation change command to change the definition, required time, etc. of the calculation; a sampling period calculation means that calculates the total calculation time of the changed calculation when the required time, etc. is changed, and calculates a new sampling period based on this total calculation time; When there is no change, the period of the sampling command of the sampling command means is left unchanged, and when there is a definition or change of the calculation, the series of calculations is executed as a new period calculated from the period of the sampling command. Digital control calculation method.