JPH1116467A - Timer with time correcting function and temperature controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give high oscillating performance with high reliability to an oscillator with low oscillating performance such as a CERALOCK(R) to reduce the cost by measuring the error of pulse signals with an outside calibrating apparatus for inputting pulse signals from the oscillator based on software controlled with a central processing unit, and correcting the output of the oscillator. SOLUTION: Pulse signals having the specified time width outputted by oscillation of an oscillator 14 when correction is conducted by a correction mode of a CPU 12 are received and measured with an outside cabibrating apparatus 18 connected to an output part 16 and an input part 17 of a timer with a time correcting function 11. Corrected values corresponding to oscillation errors calculated from measured values are inputted to the timer 11 with time correcting function 11, memorized in an EEPROM 13 with the CPU 12, and based on the memorized data, the output of the oscillator 14 is corrected. A low cost oscillator such as CERALOCK(R) or a CR oscillator can be utilized as a high accuracy timer. An output line 19 and an input line 20 connected to the outside calibration apparatus 18 may be connected by radio communication in addition to wire connection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timer with a time correction function for correcting timer accuracy, and more particularly, to a timer with a time correction function capable of obtaining high-precision timer performance regardless of the oscillation performance of an oscillator. .

[0002]

2. Description of the Related Art Generally, as shown in a control circuit diagram of FIG. 8, a timer with a time correction function of this kind has an oscillator 82 which oscillates based on software controlled by a central processing unit (CPU) 81. And a trimmer capacitor 83 for adjusting the load capacity. The output of the oscillator is inspected by a pedometer, and the oscillation error is adjusted by the trimmer capacitor according to the inspection result.

[0003] Usually, a crystal which can provide high oscillation performance is used for this oscillator, but on the other hand, the crystal oscillator is expensive. For this reason, it is conceivable to use a low-cost Ceralock or CR oscillator, but in this case, there is a problem that the use is limited to the use of a low-precision timer due to a large variation and unstable oscillation performance. Was.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention corrects the oscillation error of even a low-reliability oscillator such as CERALOCK with low oscillation performance to exhibit a highly reliable high oscillation performance. It is an object of the present invention to provide a timer with a time correction function and a temperature controller that can reduce the cost.

[0005]

According to the first aspect of the present invention,
A timer with a time correction function for correcting an oscillation error of an oscillator based on software controlled by a central processing unit. The timer outputs a pulse signal based on the oscillation of the oscillator to an external calibration device. Is used to measure the error of the pulse signal, and the output of the oscillator is corrected based on the measured value.

According to a second aspect of the present invention, there is provided a correction mode provided in software controlled by a central processing unit, an output unit for outputting a pulse signal based on oscillation of an oscillator to the outside when correcting the correction mode, An external calibration device measures the error of the pulse signal output from the output unit, an input unit that receives and inputs the measured value, a storage unit that stores the measured value input by the input unit, and a storage unit. A timer with a time correction function, comprising: a correction unit that corrects the output of the oscillator based on the stored measurement value.

According to a third aspect of the present invention, when the input unit and the output unit are connected to the external calibration device, communication means for connecting the connection units by wire or wirelessly is provided.

According to a fourth aspect of the present invention, there is provided a storage means for continuously storing the measured value of the oscillation error even when the power is cut off, and permitting re-correction.

According to a fifth aspect of the present invention, there is provided a temperature controller having a timer with a time correction function for controlling the temperature.

[0010]

According to the present invention, when correcting the oscillation error of the oscillator, a pulse signal based on the oscillation operation of the oscillator is output to an external calibration device, and the error of the pulse signal is measured by the external calibration device. The output of the oscillator is corrected based on the measured value.

When correcting the oscillation error of the oscillator based on a correction mode provided in software controlled by the central processing unit, a pulse signal based on the oscillation operation of the oscillator is output at the time of correction in the correction mode. The external calibration device measures the error of the output pulse signal, receives the measured value, inputs the measured value, and stores the input measured value in the storage unit. The correction means corrects the output of the oscillator based on the value.

[0012] When the input unit and the output unit provided on the timer side are connected for communication with the external calibration device, they are connected by wired or wireless communication means. Further, the storage means allows the output of the oscillator to be re-corrected continually, regardless of the power cut-off. Such a timer with a time correction function is provided in the temperature controller to adjust the temperature.

[0013]

As a result, when correcting the oscillation error of the oscillator provided in the timer, the oscillation error is measured by an external calibration device and corrected and managed, so that it can be used as an oscillator having high oscillation performance. As a result, even a low-oscillation performance oscillator can have high oscillation performance like a crystal oscillator, and a high-precision timer can be used. A low-cost oscillator such as a resonator can be effectively used.

Further, when connecting the timer and the external calibration device, communication can be easily established by wire or wireless, and even if the power is unexpectedly cut off,
Since the storage means keeps storing the error of the oscillator, the output of the oscillator can be permitted to be corrected again. Further, when such a timer with a time correction function is provided in the temperature controller, the temperature can be adjusted economically and accurately by performing timekeeping management.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a control circuit block diagram of a timer 11 with a time correction function.
It comprises a CPU 12, an EEPROM 13, an oscillator 14, a capacitor 15, an output unit 16, and an input unit 17, and is provided to allow communication with an external calibration device 18 for calculating an oscillation error of the oscillator 14. .

The CPU 12 has a correction mode for correcting and controlling the oscillation error of the oscillator 14. In this correction mode, the output section 16 and the input section 1 of the timer 11 are provided.
7 is connected to an external calibrator 18 by wiring, and a pulse signal of a specific time width is output when the oscillator 14 oscillates. The external calibrator 18 receives and measures the pulse signal, and calculates an oscillation error from the measured value. A correction value corresponding to the oscillation error is notified to the loopback timer 11 to be notified. CPU based on this
Numeral 12 corrects the oscillation error of the oscillator 14, and can switch from an oscillator with low oscillation performance to an oscillator with high oscillation performance.
The timer 11 can be used as a high-precision timer regardless of the oscillation performance of the oscillator.

Incidentally, the timer 1 with the time correction function
1 is an external calibrator 18 only when it is necessary to improve the oscillation performance of the oscillator 14 such as when a timer is shipped from the manufacturer.
To correct the oscillation error, and connect the output line 16 with the output section 16 on the timer side when connecting this wiring.
, And receives a pulse signal of a specific time width at the time of oscillation output from the timer side. Also, the input unit 17
Is connected via an output line 20, and the oscillation correction value calculated by the external calibration device 18 is repeatedly input to the timer 11 as response information. At this time, C
The PU 12 stores the correction value input to the timer 11 in the EEPROM 13 as an external storage unit, and completely corrects the output of the oscillator 14 based on the stored correction value.

The timer 11 with a time correction function has a 1 ms timer interrupt therein, and the timer function is realized by counting the timer interrupt.

FIG. 2 shows a time chart of a timer having a time correction function. An oscillator which oscillates and outputs 10 MHz is used. At this time, the CPU 12 divides the frequency by 1/4 as a reference clock for timer interrupt and outputs the signal at 2.5 MHz. I'm using
Therefore, since one clock is 400 ns, a reference value of 2500 (2500 × 400 ns = 1 ms) count is set in the timer interrupt time register in order to create a 1 ms timer interrupt. Also, the oscillator used here has a low oscillation performance and has an error of, for example, about -0.2% (10 MHZ x 0.998 = 9.98 MH)
Z).

(A) When the oscillator 14 has a variation of about -0.2%, the CPU 12 intends to generate a timer interrupt accurately every 1 ms. 002 ms (2500 counts / 9.98 MH
Z = 1.002 ms).

(B) The CPU 12 is the external calibration device 1
When receiving the correction mode start command signal 17a from FIG.
In the correction mode, a pulse signal of a reference count (2500 ms) is output to the external calibration device 18. At this time, the reference count (2500 ms)
Is output, the actual reference count pulse signal 16a is 1.002 × 2500 = 2505
ms output.

(C) The external calibration device 18 receives the output pulse signal 16a of the reference count, measures the pulse output width, and compares the pulse output width with the reference value to obtain an error (in this case, +
5) is calculated, and the correction value (in this case, -5) obtained in accordance with the calculated value is notified to the timer 11 side.

(D) When a correction value is input from the external calibration device 18 to the input section 17, the timer 11 outputs the correction value to the EE.
The timer interrupt time is corrected by setting the value of reference count (2500) + correction value (−5) = correction set value (2495) in the timer interrupt time register.

Thus, the oscillator becomes (2500-5) / (9.98 MHz / 4) = 1.00.
It demonstrates high oscillation performance with ms.

As described above, since the oscillation error of the oscillator 14 is measured and corrected and managed by the external calibration device 18, even an oscillator having low oscillation performance can be used as an oscillator having high oscillation performance. Therefore, even low-cost oscillators such as CERALOCK and CR oscillators, which have been limited in use while being low in cost, can have high oscillation performance like a crystal oscillator. Regarding the connection between the timer 11 and the external calibration device 18, not only the wired connection using the output line 19 and the input line 20 but also the communication connection can be easily performed wirelessly. Further, even if the power is unexpectedly cut off, the correction value of the oscillator 14 is continuously stored in the EEPROM 13, so that the output of the oscillator can be corrected and used every time the timer is started. It can be used as a high-performance timer that always eliminates oscillation errors.

The processing operation of the timer 11 with the time correction function configured as described above will be described with reference to the flowchart of FIG. Now, when a command signal is input from the external calibration device 18 to the input unit 17 of the timer 11 (step n1),
If the input command signal is in the correction mode for requesting the correction of the oscillator, the CPU 12 sets the correction mode (steps n2 to n3), and sends the reference count pulse signal (2500 ms) to the timer interrupt time register. The pulse signal of the reference count is output to obtain the correction value (step n4).

When a command signal for a correction value is input from the external calibration device 18 to the input section 17 of the timer 11 (step n5), the CPU 12 stores this correction value in the EEPROM.
After storage and management in the memory 13 (step n6), the correction set value obtained by adding and subtracting the correction value from the reference value is reset as the timer interrupt time. As a result, the timer interrupt time changes and the oscillator with low oscillation performance becomes an oscillator with high oscillation performance. In this way, the variation of the oscillator is corrected, and a highly accurate timer function is obtained (step n7).

After the completion of the correction, the correction mode is reset, and the correction operation for the oscillator 14 ends (step n8).

Next, 1 m of the timer 11 with the time correction function
The timer interrupt operation of s will be described with reference to the flowchart of FIG. When the correction mode is set, the CPU 12
Based on this correction mode, a reference count pulse signal (2500 ms) is set in the timer interrupt time register and output (steps n11 to n15).

On the other hand, if the correction value is the correction value extracted in the correction mode, the CPU 12 controls and corrects until the correction value is reached (steps n16 to n18).

FIG. 5 is a block diagram showing a control circuit of a timer 51 with a time correction function according to another embodiment of the present invention.
M53, oscillator 54, capacitor 55, output unit 5
6 and an input unit 57, and is provided so as to allow communication with an external calibration device 58 that calculates an oscillation error of the oscillator 54.

This corresponds to an EE provided as an external storage unit.
Instead of the PROM, a correction value expected in advance is prepared in a correction value table 59 in a program stored in the ROM 53, and for example, the first to fourth switches SW1 to SW4 provided according to a plurality of correction setting patterns are provided. By selecting a specific switch from the correction value table 59 corresponding to the correction value and turning on the switch by the input unit 57 provided with SW4,
This is to correct the oscillation error of the timer by correcting the timer interrupt time.

On the other hand, the external calibration device 58 measures the pulse signal of the reference count to calculate an oscillation error, and obtains a correction value from the calculated measurement value. At this time, the correction value is transmitted from the external calibration device 58 to the timer 51 with a time correction function, and based on the correction value, the CPU 52 turns on one of the switches SW1 to SW4 of the input unit 57 corresponding to the correction value.

FIG. 6 is a control circuit block diagram in which the timer with a time correction function of the present invention is applied to a temperature controller 61. This temperature controller 61 includes a CPU 62, a program storage unit 63, an oscillator 64 , A capacitor 65, an output section 66, and an input section 67.
Is provided so as to allow communication with an external calibration device 68 that calculates the oscillation error of the above.

When the CPU 62 is in the correction mode, the oscillator 6
In the oscillation operation of Step 4, a pulse signal of the reference count is output, and the pulse signal is received and measured by the external calibration device 68, the measured value is compared with the reference value to calculate an error, and a correction value corresponding to the error is calculated. An answer is given to the input unit 67 of the turnback temperature controller 61. According to the correction value, the CPU 62 corrects the time setting value of the temperature controller 61 programmed by the user, and eliminates the error of the temperature controller 61 in advance. After the correction is completed, the correction value is stored as continuation data in the program storage unit 63 and stored and managed.

FIG. 7 shows a program table 71 set in the program storage section 63 of the temperature controller 61. The program table 71 includes, for example, 50.degree.
Are set in correspondence with the respective temperature set values of 10 minutes, 50 minutes,..., And a correction value α is set for each set value corresponding to this temperature and time.
By setting the time in consideration of the correction value α, a highly accurate timer function is exhibited. For this reason, the temperature controller 61 does not require an expensive oscillator, a high-performance timer operation is obtained using an economical oscillator, and the temperature is accurately adjusted according to a program determined by the user.

As described above, when correcting the oscillation error of the oscillator provided in the timer, the oscillation error is measured and obtained by an external calibration device, and based on this, the oscillation error is corrected. Even if it is used, it can be used by switching to an oscillator having high oscillation performance. Therefore, a high-precision timer can be used by effectively using a low-cost oscillator such as a CERALOCK or CR oscillator, and the timer application is expanded.

In correspondence between the present invention and the configuration of the above embodiment, the central processing unit and the correcting means of the present invention
In the same manner, the storage means corresponds to the EEPROM 13, the ROM 53, and the program storage unit 63, and the communication means corresponds to the output line 19 and the input line 20. The invention is not limited only to the configuration of the above embodiment.

[Brief description of the drawings]

FIG. 1 is a control circuit block diagram of a timer with a time correction function according to the present invention.

FIG. 2 is a time chart of the timer with a time correction function of the present invention.

FIG. 3 is a flowchart showing a processing operation of a timer with a time correction function according to the present invention.

FIG. 4 is a flowchart showing a 1 ms timer interrupt operation of the present invention.

FIG. 5 is a control circuit block diagram of a timer with a time correction function according to another embodiment of the present invention.

FIG. 6 is a block diagram of a control circuit in which the timer with a time correction function of the present invention is applied to a temperature controller.

FIG. 7 is an explanatory diagram showing a program table of a program storage unit of the present invention.

FIG. 8 is a control circuit block diagram of a conventional timer with a time correction function.

[Explanation of symbols]

 11, 51: Timer with time correction function 12, 52, 62 CPU 13: EEPROM 14, 54, 64 ... Oscillator 16, 56, 66 ... Output unit 17, 57, 67 ... Input unit 18, 58, 68 ... External Calibration device 19 ... output line 20 ... input line 53 ... ROM 61 ... temperature controller 63 ... program storage unit 71 ... program table

Claims (5)

[Claims] 1. A timer with a time correction function for correcting an oscillation error of an oscillator based on software controlled by a central processing unit, wherein the timer outputs a pulse signal based on the oscillation of the oscillator to an external calibration device. A timer with a time correction function that measures the error of the pulse signal with the external calibration device and corrects the output of the oscillator based on the measured value. 2. A correction mode provided in software controlled by a central processing unit, an output unit for outputting a pulse signal based on oscillation of an oscillator during correction in the correction mode, and an output unit output from the output unit. An external calibration device measures the error of the pulse signal, and an input unit that receives and inputs the measured value, a storage unit that stores the measured value input by the input unit, and a measurement value that is stored by the storage unit. A timer with a time correction function, comprising: a correction means for correcting the output of the oscillator. 3. The timer with a time correction function according to claim 2, wherein the input unit and the output unit are provided with a communication unit that is connected to the external calibration device by a wired or wireless connection. 4. A timer with a time correction function according to claim 2, wherein said storage means continuously stores and permits re-correction even when power is cut off. 5. A temperature controller comprising a timer with a time correction function according to claim 1, 2 and 3 for temperature control.