JP2000131473A - Timer device and its adjusting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a timer device whose adjustment does not require the time and a skilled technique and in which it is not required to attach a component for adjustment to individual oscillators and to provide its adjusting method. SOLUTION: An input terminal to which an external oscillator is connected is installed. When a time adjusting mode is set in S1 (Step 1), a reference oscillator is connected to the input terminal (S2). The oscillation signal of the reference oscillator is inputted to an input port. Then, in a control part, the oscillation signal of the reference oscillator is read out for a set time (S3), the oscillation frequency of an internal oscillator is read out (S4), and a difference frequency between both is stored (S5). After that, this procedure is shifted to an ordinary operating mode (S11), and the oscillation frequency of the internal oscillator is corrected (S14) in every set time on the basis of the stored difference frequency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for automatically adjusting the oscillation frequency of an oscillator incorporated in an electronic timer, clock or the like.

[0002]

2. Description of the Related Art FIG. 4 is a circuit block diagram of a conventional timer device such as an electronic timer or a clock. In FIG. 4, a control unit 11 has a built-in CPU 2,
A memory 4 and a counting unit 5 are provided, 6 is an operation unit having a switch and the like, 7 is a display unit for displaying time and the like, and 8
Is a built-in oscillator connected to the counting unit 5 via a trimmer capacitor 10. Since the oscillator 8 has a variation in the oscillation frequency, the oscillation frequency is adjusted by adding, for example, a trimmer capacitor 10 in series with the oscillator 8 as a component for frequency adjustment, so that the oscillation frequency becomes accurate. . This adjustment is performed by adjusting the trimmer capacitor 10 while measuring the frequency of the oscillator 8 with a frequency counter (not shown) so that the oscillation frequency becomes a specified value.

[0003]

However, the above-mentioned adjustment method requires skill and time because the adjustment operation is delicate, and requires a component for adjustment for each oscillator. . In addition, since the adjustment work is performed at the stage of assembling the board, it is necessary to disassemble the device to adjust the product once assembled, which is troublesome.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a timer device and a method of adjusting the timer device which do not require time and skill for adjustment, and which do not need to attach adjusting components to individual oscillators. And

[0005]

According to a first aspect of the present invention, there is provided a timer apparatus comprising: an input unit for inputting an external transmission signal; and a frequency of an external oscillation signal input from the input unit. A first counting means for counting; a second counting means for counting the frequency of the internal oscillator; a difference calculating means for calculating a difference between the frequencies counted by the first and second counting means; It has a storage means for storing and a time determination means for determining the time by correcting the oscillation frequency of the internal oscillator based on the stored difference frequency.

A timer device adjusting method according to a second aspect of the present invention is a timer device adjusting method for determining the time by counting the oscillation frequency of an internal oscillator, wherein an outgoing signal is input from outside and the frequency is adjusted. Counting, calculating the difference frequency between the frequency of the internal oscillator and the number of external oscillation waves, storing the calculated difference frequency, correcting the frequency of the internal oscillator based on the stored difference frequency, and determining the time. It is configured as follows.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a circuit block diagram of a timer device according to the present invention, and the same components as those in FIG. 4 are denoted by the same reference numerals. As shown in the figure, the control unit 1 is a computer, having a memory such as a ROM 3 and a RAM 4 centering on a CPU 2, an operation unit 6 and a display unit 7 are connected, and two counting units 5a and 5b are provided. . The oscillator 8 is a built-in oscillator connected to one counting unit 5a (second counting unit) of the control unit 2, and the other counting unit 5b (first counting unit) is connected to the input port 9, The input port 9 is connected to an input terminal 13 which is a signal input means provided in the timer device. In addition, 1
Reference numeral 2 denotes an external reference oscillator connected to an input terminal for adjustment.

Next, the procedure for adjusting the timer device will be described with reference to the flowchart of FIG. First, in S1 (step 1), the switch provided on the operation unit 6 is operated to switch to the adjustment mode, the input terminal is used as the frequency input terminal, and the accurately adjusted reference oscillator 12 is connected (S2). still,
The reference oscillator 12 outputs the oscillation frequency that the oscillator 8 should originally output. When the reference oscillator 12 is connected, the process proceeds to S3, where the frequency of the reference oscillator 12 is read for a certain period of time, and the frequency of the oscillator 8 is read in S4.
The control unit 1 as the difference calculation means calculates the difference frequency between the two, and stores the difference frequency in the RAM 4 as the storage means (S5).

After storing the difference frequency, the adjustment mode is terminated, and the switched switch is returned to the normal operation mode. When the operation mode is returned to the normal operation mode (S11), the operation of counting time is started by the built-in oscillator 8 (S12), and the process proceeds to S13 to determine whether a predetermined time has elapsed. Corrects the transmission frequency based on the difference frequency stored in S5, and ticks the time using the corrected frequency.

As described above, by simply connecting an accurate oscillator to the input terminal, the difference frequency between the reference oscillator and the built-in oscillator is stored, and the oscillation frequency of the built-in oscillator is corrected based on the difference frequency. Therefore, an adjusting element such as a trimmer capacitor does not need to be provided for each oscillator, and a timer device can be adjusted without a measuring instrument for adjustment. This adjustment method is performed by the CPU 2 in the control unit.
Can be adjusted in a short time without the need for delicate adjustment work or skilled skills.

Further, since adjustment is performed by connecting a reference oscillator to the input terminal, readjustment after assembly can be easily performed, and a measuring instrument for adjustment is not required at the time of adjustment. Therefore, even if the transmission frequency needs to be adjusted again after a long period of time, it can be easily adjusted again by the above procedure. Further, since the input terminal is switched to the reference oscillator connection terminal by a switch operation, it is possible to use the terminal for another purpose, and the present invention can be implemented without providing a new terminal for adjusting the oscillation frequency.

FIG. 3 is a flowchart showing an adjusting method according to another embodiment. In this case, no changeover switch is provided, and
The input terminal 13 is a dedicated input terminal for the reference oscillator 12, and is set so that the adjustment mode is automatically set when the reference oscillator 12 is connected to the input terminal 13. Unless an oscillator is connected to the input terminal 13, the timer device performs a normal operation of correcting the time based on the difference frequency already stored every time a predetermined time elapses and counting the time. If the difference frequency has not been calculated, the correction operation may be performed with the difference set to 0.

When the reference oscillator 12 is connected to the input terminal 13 (S24), it is determined that the mode is the adjustment mode, and the process proceeds to S26.
Then, the transmission frequency of the connected reference oscillator 12 is read for a certain period of time, the frequency of the built-in oscillator 8 is read (S27), the two are compared, and the difference frequency is calculated and stored (S28). Then, the process proceeds to S29, and the end of the adjustment mode is notified by sounding an alarm.

As described above, the reference oscillator 1 is connected to the input terminal 13.
The adjustment mode may be entered simply by connecting the device 2. If the adjustment mode is ended, an end of the adjustment is notified by an alarm or the like, the end of the adjustment can be easily confirmed, and the adjustment can be performed reliably. .

[0015]

As described above in detail, according to the first and second aspects of the present invention, by connecting the reference oscillator to the input means,
Since the time determining means adjusts the oscillation frequency of the internal oscillator to keep time, there is no need to provide an adjusting element such as a trimmer capacitor for each internal oscillator, and a measuring instrument for adjustment is not required. Provision of the input means also facilitates readjustment after product assembly. Further, the transmission frequency can be adjusted by simply connecting the reference oscillator, and the adjustment can be easily performed in a short time without requiring any skill.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram of a timer device showing an example of an embodiment of the present invention.

FIGS. 2A and 2B are flowcharts showing an adjustment method of the timer device of FIG. 1, wherein FIG. 2A shows an adjustment mode, and FIG. 2B shows a normal operation mode.

FIG. 3 is a flowchart of an adjustment method showing another embodiment of the present invention.

FIG. 4 shows a circuit block diagram of a conventional timer device.

[Explanation of symbols]

1. Control unit, 2. CPU, 3. ROM, 4. R
AM, 5a, 5b, counting section, 6 switch operation section,
7 ··· Display unit, 8 ··· Oscillator, 9 ··· Input port, 12
..Reference oscillator, 13 input terminals.

Claims (2)

[Claims] 1. An input means for inputting an external transmission signal, a first counting means for counting the frequency of an external oscillation signal input from the input means, and a second counting means for counting the frequency of an internal oscillator. A difference calculating means for calculating a difference between the frequencies counted by the first and second counting means, a storage means for storing the difference frequency, and correcting the oscillation frequency of the internal oscillator based on the stored difference frequency. A timer device having a time determining means for determining a time by using a timer. 2. A method for adjusting a timer device for counting an oscillation frequency of an internal oscillator and determining a time, wherein a transmission signal is input from the outside, the frequency is counted, and the frequency of the internal oscillator and the external oscillation A method for adjusting a timer device, comprising calculating a difference frequency from a wave number, storing the calculated difference frequency, and correcting the frequency of the internal oscillator based on the stored difference frequency to determine a time.