JPS59100910A - Reading method of parameter in control device - Google Patents

Abstract

PURPOSE:To read exactly a parameter by changing a read time interval of parameters which are set when the control is being stopped and when the control is being executed, and making a data effective and processing it only when they coincide with each other continuously. CONSTITUTION:Control parameters such as a temperature, a PID constant, etc. are set by a setting part 2, and by a control part 6 consisting of a central processing unit (CPU) and an ROM, a temperature of a control object 3 is controlled through an output part basing on a sensor input obtained from a sensor part 4. A memory (RAM) 7 has an area for storing various informations required for inputting the parameter. When reading this parameter, a sampling time whose control is being stopped is set to T, a sampling time whose control is being executed is set to 4T of a longer period than that which is being stopped, and also, only when the parameters read by this sampling coincide with each other (the previous and the present sampling values coincide with each other) continuously, it is made effective and processed, by which the influence of a noise is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for reading parameters used in temperature, humidity, etc. control devices.

BACKGROUND OF THE INVENTION A temperature or humidity adjusting device or the like includes an output device that includes a heater, a motor, etc. and actually controls a controlled object, and a control section that controls the output device.

In such devices, it is necessary to input various parameters to the control unit, but since the output device includes a noise source such as a motor, it may be affected by noise, so inputting the correct parameters will make it easier to use. There was a problem that there was a possibility that it would malfunction.

By the way, in a temperature and humidity control system, it is not possible to change the temperature and humidity of the controlled object so rapidly, so it is acceptable even if the speed at which parameters are input is relatively slow. Further, when the output device is operated to drive the controlled object, a lot of noise is generated. Uncertain changes in the parameters set at this time due to noise may have a very negative effect on the controlled object.

Therefore, it is necessary to reliably import parameters in the control state. On the other hand, when the power is turned on and when the output device is not being driven, it is highly necessary to change the parameters, and when the output device is not operating, noise is hardly generated.

Purpose of the Invention The present invention has been made in view of the characteristics of setting parameters of a control device such as temperature and humidity, and it is possible to reliably set parameters without complicating the configuration. The purpose is to provide a method for reading parameters.

Structure and Effects of the Invention The present invention is a method for reading control parameters in a control device, in which parameters to be set are read at each first time interval while the control is stopped, and parameters to be set are read at the first time interval while the control is being executed. The data is read every second time interval that is longer than the first time interval, and the data is processed as valid only when the read parameters match continuously.

In this way, according to the present invention, during a control stop, the
During control execution, parameters input in long cycles are read. During control execution, the input parameters are relatively often different from the input values due to the influence of noise, but it is unlikely that the parameters will remain the same throughout a certain period of time. Therefore, the longer the cycle for reading the parameter measurements during control execution, the less likely an error will be to occur, resulting in the effect that parameters can be read accurately.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 is an overall configuration diagram showing an example of a temperature control device using the parameter reading method of the present invention.

In this figure, a temperature control device 1 includes a setting section 2 that sets temperature and control parameters such as P, I, and D constants, a sensor section 4 that is installed on a controlled object 3 and detects its temperature, and an output that includes a heater, a motor, etc. A section 5 and a control section 6 are provided. The control unit 6 has a central processing unit (hereinafter referred to as CPU) and a read-only memory (hereinafter referred to as ROM), and outputs information to the controlled object 3 via the output unit 5 based on the sensor input obtained from the sensor unit 4 according to a predetermined processing procedure. This is to control the temperature of the Memory 7 consists of random access memory;
As shown in FIG. 2, it has an area for storing various information necessary for importing parameters.

That is, the read value area R indicating the read value of the parameter
p, parameter buffer E3p that temporarily holds parameter values, parameter setting value area Sp that holds parameter values to be set, power-on flag Fo that indicates power-on.
n, a cycle counter c1 indicating the parameter reading cycle, a control execution flag Fc indicating that control is being executed for the controlled object, a sampling counter Cs determining the sampling period, and a sampling flag Fs that is set at the time of sampling.

Next, the operation of the temperature control device will be explained with reference to the flow yard. In the flowcharts below, numbers indicated using leader lines indicate processing routines or operation steps of the control section 6.

FIG. 3 is a flowchart showing the operation steps of the temperature control device. First, when the power is turned on, an initialization process is performed in step 20 in which the power-on flag Fon and the control execution flag Fc are reset and the cycle counter C is set to zero. Next, in step 21, the sampling counter Cs is set to a predetermined value, and the sampling flag F is set to a predetermined value.
Perform sampling initialization processing to reset s. Then, the temperature of the controlled object 3 is read via the sensor unit 4 (
In step 22), the temperature setting value set from the setting unit 2 in step 23 is read. Then, in routine 24, a parameter setting process is performed to input the set parameters into the temperature control device, and in step 25, the power-on flag Fon is set.

Thereafter, calculation processing for temperature control is performed based on a predetermined processing procedure (step 26), and the process proceeds to step 27, where the control state is checked based on the control execution flag Fc. If control is being executed, output change processing is performed in step 28, and if control is not being executed, a cycle counter Cc is incremented in step 30 after a patent characterized by the output in step 29, and the value of this cycle counter Cc is is 4 (Step 7, Step 31). If it is 4, the process proceeds to step 32 and resets the cycle counter CC, and if it is not 4, the process skips step 32 and proceeds to step 33, where it is checked whether the sampling flag Fs is set.

In this step, a time wait is performed, and if the time is set, the process returns to step 21 and the same process is repeated thereafter.

Next, FIG. 4 is a flowchart showing timer interrupt processing, and this processing is performed when an interrupt is generated by the timer at regular intervals. When there is an interrupt, first in step 34 the sampling counter Cs is decremented, and then in step 3
5, it is checked whether a borrow output is output from the sampling counter Cs. If there is a borrow output, the sampling flag FS is set at the step knob 36 to end the interrupt processing, and if there is no borrow output, the direct interrupt processing is ended. In this way, the sampling flag Fs is controlled to be set to 1 at regular intervals, and the parameter reading process is performed according to the routine of steps 21 to 33 accordingly.

Now, the parameter setting processing routine 23 will be explained in detail with reference to the flowchart of FIG. When this routine is entered, first in step 40 it is checked whether the power-on flag Fon is in the reset state. If this flag is in the cent state, it is checked in step 41 whether control is being executed based on the control execution flag Fc. If control is being executed, step 42
Then, it is checked whether the count value of the cycle counter Cc is zero. If control is not being executed or if the count value of the cycle counter Cc is zero, the set parameters are read into the parameter reading area Rp in step 43. Then, in step 44, a comparison is made with the data held in parameter buffer B (step 44). If they match, the read parameter value is placed in the parameter setting value area Sp (step 45), and if they do not match, the read data is moved to the parameter buffer B (step knob 46).
This processing routine ends. Further, if the cycle counter Cc in the steering knob 42 is not zero, this processing routine is ended without reading any parameters.

Next, the operation when reading parameters will be further explained in detail using a time chart. Figure 6(a),
(b) is a time chart showing the parameter reading operation when the power is turned on, when the control is stopped, and when the control is being executed, respectively. Assuming that the power is turned on at time t1 in FIG. 6(a), the steering knob 20 is initialized and the parameter setting processing routine 24 is entered through steps 21-23. Here, since the power-on flag Fon is in the reset state, the parameters are read (step 43), and the parameters are held in the parameter buffer B (step 46). Next, the output processing is performed in steps 25 to 33 as described above, and in step 33, the process waits for the cycle update time. Thereafter, the timer interrupt processing power shown in FIG. 4 is repeated, and when the sampling counter Cs, which has been set to a predetermined value in step 21, outputs a borrow output and the sampling flag FS is set, the process returns from step 33 to step 21. In this way, the loop of steps 21 to 33 is repeated for each sampling tie and AT. At this time, if the control is stopped, the cycle counter C
Since the parameters are read regardless of the state of c (
Steps 41-43), parameters are read at every sampling time T as shown in Fig. 6 (al). - If force control is being executed, the loop of steps 21-33 is
After each cycle, the cycle counter Cc is reset (steps 31, 32), and the parameters are read only in the cycle following the reset (steps 42, 43).

Therefore, as shown in FIG. 6(b), parameters are read every four times the sampling time, that is, every 4T. The parameters are made valid only when the parameters thus read match the parameters read last time (step 45).

However, although the input parameters may have different values due to the influence of noise, the errors are random, and the possibility that the input parameters will be different values during a certain time period is extremely small. The longer this time period is, the less likely this error will occur. Therefore, as shown in FIG. 6(b), the more the parameters are read at intervals, the fewer reading errors occur.

Although this embodiment has described a method for reading parameters in a temperature control device, the present invention can be applied to reading parameters in various control devices that require a relatively slow data reading speed.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an example of a temperature control device using the variable make reading method of the present invention, FIG. 2 is a memory map of the memory 7, FIG. 3 is a flowchart showing the operation of this temperature control device, and FIG. 4 is a FIG. 5 is a flowchart showing the timer interrupt processing of the temperature control device, FIG. 5 is a flowchart showing the parameter reading processing routine, and FIG. 6 (al,
(bl is a time chart for explaining the parameter reading operation during control stop and control execution, respectively. Output section 6---Control section 7--Memory F on--Power on flag Cc--Cycle counter Fc-- 1 Control Execution Flag Patent Applicant Tateishi Electric Co., Ltd. Agent Patent Attorney Yoshiki Okamoto (and 1 other person) Figure 1 Figure 3 Figure 4

Claims (2)

[Claims] (1) A method for reading control parameters in a control device, wherein parameters to be set are read at each first time interval while the control is stopped, and parameters to be set are read at the first time interval while the control is being executed. A method for reading parameters in a control device, characterized in that the data is read at every second time interval longer than , and the data is processed as valid only when the read parameters match continuously. (2) The parameter reading method according to claim 1, wherein the control device is a temperature/humidity control device.