JPH11326556A - Time information-receiving device and clock with time correction function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the correction accuracy of an existing electronic-wave correction clock for correcting time according to an on-the-hour signal such as a time signal. SOLUTION: When a correction request signal is outputted from a display- driving part 103, a time information reception device 1 receives the signal for operating a long-wave receiver 215 after 23 hours 55 minutes, detects time information according to a timecode signal, and corrects the time of an internal clock 4a. When the correction request signal is outputted for the second time after the correction, the time information reception device 1 outputs an on-the- hour signal to the display-driving part 103 based on the clocking time of the internal clock 4a. The display-driving part l 03 corrects the display time of a time display part 101 according to the on-the-hour signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a time information receiving apparatus and a timepiece with a time correction function.

[0002]

2. Description of the Related Art Conventionally, there is a radio-controlled timepiece which detects an hour signal from a time signal of an FM radio or the like and corrects a display time of a time display unit based on the detected hour signal.

A timepiece of this type generally comprises hands 101a, 101b, etc. as shown in FIG. 4, a time display unit 101 for displaying the current time, an hour signal receiving unit 102 for detecting an hour signal, and a time display unit. A display driving unit 1 that operates 101 and corrects the display of the time display unit 101 based on the hour signal detected by the hour signal receiving unit 102
03 and the like.

FIG. 4 will be described briefly.
Reference numeral 3 denotes a CPU, a ROM, a RAM, and the like.
The control circuit 111 includes a control circuit 111, a crystal oscillator 112 that outputs a reference clock signal, a clock driver 113 that outputs a hand operation signal to the time display unit 101, and the like. Control circuit 1
11 is slightly before the internal clock 111a measures the hour (30
An hour signal detection request signal (hereinafter, referred to as a “correction request signal”) is output from about 1 second before), and the hour signal receiving unit 10
Operate 2 The hour signal receiving unit 102 includes an antenna 114, an FM radio receiver 115, and a time signal detector 11
The operation is started by a correction request signal from the display driver 103, and when an hour signal is detected, the hour signal is output to the display driver 103 as a correction (synchronization) signal.

[0005] That is, in the case of FIG.
Outputs a correction request signal slightly before the internal clock 111a of the control circuit 111 measures the hour, and corrects the time based on a correction (synchronization) signal indicating the hour output from the hour signal receiving unit 102. Things.

Further, unlike the above, a time code signal (long-wave standard radio wave) in which one minute is one data frame is received, and based on the received signal, a long-wave standard signal for correcting the display time of a time display section is provided. In recent years, radio-controlled watches using radio waves have been rapidly spreading.

This type of timepiece has a hand 2 as shown in FIG.
01a, 201b, etc., a time display unit 201 for displaying the current time, a time code signal receiving unit 202 for detecting the time code signal, and a time code signal detected by the time code signal receiving unit 202 for operating the time display unit 201 And a display drive unit 203 that corrects the display of the time display unit 201 based on the above.

Referring to FIG. 5, the display drive section 203 has a C
Control circuit 211 having PU, ROM, RAM and having an internal clock, crystal oscillator 21 for outputting a reference clock signal
2 and a clock driver 213 that outputs a hand movement signal to the time display unit 201. The control circuit 211 outputs the time code signal detection request signal several minutes before the internal clock measures the hour (about 5 minutes before), and operates the time code signal receiving unit 202. Time code signal receiving unit 20
2 includes an antenna 214, a long-wave receiver 215 for receiving a time code signal, a decoding control circuit 216, and the like.
The operation starts in response to a time code signal detection request signal from the display drive unit 203, and when time data is detected, the time data is output to the display drive unit 103.

That is, in the case of FIG.
Is to output a time code signal detection request signal several minutes before the internal clock of the control circuit 211 measures the hour, and correct the time based on the time data output from the time code signal receiving unit 202.

In this case, since the time code signal is continuously transmitted every minute, even if noise of 1 or 2 seconds suddenly occurs during reception, if the reception is continued for several minutes, the time is surely increased. Data can be detected.

[0011]

The former has already been installed in various places as equipment clocks, but has the problem that it may malfunction due to noise or the like when a time signal is generated. Further, when a time signal cannot be detected due to noise or the like when a time signal is generated, there is a disadvantage that the user must wait several hours to detect the next time signal. That is, there was a problem with the time signal receiving system.

Therefore, it is conceivable to use the latter time code signal receiving unit 202 having high reception accuracy as the former receiving unit already installed. As described above, the signals output from the display driving units 103 and 203 are used. Are not identical and cannot simply be replaced. More specifically, since the signal for instructing the start of the operation of the receiving system from the former display driving unit 103 is slightly before the hour, the latter is used to operate the latter time code signal receiving unit 202. A problem arises in that it is not possible to receive a time code signal including time information and having one minute as one frame.

To solve this problem, it is conceivable that the time code signal receiving unit 202 is always operated, but in this case, there is a problem that power consumption increases.

[0014]

According to the present invention, a control means detects a time code signal from a point in time when a desired time elapses from the input of a correction request signal from the outside and obtains time information. The detection operation is stopped, and the clock time of the clock means is corrected based on the time information obtained from the time code signal, and when the next correction request signal is input from the outside, based on the clock time of the corrected clock means, To output an hour signal. Therefore, an hour signal can be output based on time information obtained from the time code signal when the correction request signal is input. Therefore, it is possible to solve the problems of erroneous correction due to erroneous detection of a time signal, sudden reception failure and hence correction, and stability of operation stability due to general broadcast waves. Further, since the time code signal is not always detected, power saving can be achieved.

The control means includes a counter means for starting counting after the correction request signal is inputted, and a judgment for outputting a reaching signal when the count value of the counter means reaches a value corresponding to the desired time. Means and a stop mode until the determination means outputs the arrival signal. When the arrival signal is output, the time code signal detection means is operated, and the time information is detected based on the detected time code signal. When the operation of the time code signal detecting means is stopped after obtaining the time, the time of the time measuring means is corrected based on the time information obtained from the time code signal, and the next correction request signal is input from the outside. And a control circuit for outputting an hour signal based on the time measured by the corrected time measuring means, so that in addition to the above-described effects, further power saving is achieved. Achieved.

The desired time is changed according to the length of time from when the operation of the time code signal detecting means stops until the next correction request signal is input from the outside.
For example, if the reception time is good and the time required to obtain the time information is short, the desired time is extended to shorten the time from obtaining the time information to outputting the hour signal, thereby reducing the accuracy of the time information. In this case, if the reception condition is poor and the time is long, the desired time can be shortened to extend the time code signal detection operation, and the time information can be reliably obtained. Can be done.

The control means detects a time code signal in response to the input of the correction request signal and outputs an hour signal based on the time counted by the timer circuit. From the time code signal detection operation is stopped, and the time measured by the clock means is corrected based on the time information obtained from the time code signal. Counting becomes unnecessary, and operation can be simplified and power consumption can be reduced.

A time information receiving apparatus as described above displays a current time, outputs a correction request signal at a desired time, and corrects the time by an hour signal, that is, a conventional radio time signal or the like. When used in combination with the time display section, the display time of which has been corrected by the hour signal, the same effect as described above can be obtained, and the display time has been corrected by the conventional time signal (hour signal) of radio waves. The time of the time display unit can be corrected using the time information receiving device as described above. Therefore, the time display unit already installed can be used as it is, and the time can be corrected with high accuracy.

[0019]

The invention according to claim 1 of the present application comprises a time code signal detecting means for detecting a time code signal, and a time measuring means for performing a time counting operation based on time information obtained from the time code signal. Operating the time code signal detecting means at a point in time when a desired time has elapsed after the external correction request signal is input, and obtaining time information based on the detected time code signal, and then operating the time code signal detecting means. Is stopped, and the clock time of the clock means is corrected based on the time information obtained from the time code signal.When the next correction request signal is input from the outside, the clock time of the corrected clock means is corrected. Control means for outputting an hour signal based on the time.

According to a second aspect of the present invention, the control means includes a counter means for starting counting after the correction request signal is inputted, and a count value of the counter means being set to a value corresponding to the desired time. A determination unit that outputs a reaching signal when the vehicle arrives, and the stop mode is set until the determination unit outputs the reaching signal.When the reaching signal is output, the time code signal detecting unit is operated. After obtaining the time information based on the detected time code signal, stop the operation of the time code signal detection means, correct the time of the time measurement means based on the time information obtained from the time code signal, When a next correction request signal is input from the outside, the control circuit outputs an hour signal based on the time measured by the corrected time measuring means.

In the invention according to claim 3 of the present application, the desired time is changed according to the time required from the previous operation of the time code signal detecting means to the obtaining of the time information.

According to a fourth aspect of the present invention, there is provided a time code signal detecting means for detecting a time code signal, a time measuring means for performing a timekeeping operation based on time information obtained from the time code signal, The time code signal detecting means is operated in response to the input of the correction request signal, and an hour signal is output based on the clock time of the clock circuit. After the output of the hour signal, the time is detected from the detected time code signal. Control means for acquiring information, thereafter stopping the operation of the time code signal detecting means, and correcting the time measured by the time measuring means based on the time information obtained from the time code signal.

The invention according to claim 5 of the present application displays the current time, outputs a correction request signal at a desired time,
A time display unit for correcting the time by the hour signal, a time code signal detecting means for detecting the time code signal, a time measuring means for performing a timekeeping operation based on time information obtained from the time code signal, and the correction request The time code signal detecting means is operated from a point in time when a desired time has elapsed after the signal is output, and after the time information is obtained based on the detected time code signal, the operation of the time code signal detecting means is stopped. Correcting the clock time of the clock means based on the time information obtained from the code signal, and when the next correction request signal is output from the time display unit, the time based on the corrected clock time of the clock means is corrected. Control means for outputting an hour signal to the display unit.

According to a sixth aspect of the present invention, the control means includes a counter means for starting counting after the correction request signal is input, and a count value of the counter means being set to a value corresponding to the desired time. A determination unit that outputs a reaching signal when the vehicle arrives, and the stop mode is set until the determination unit outputs the reaching signal.When the reaching signal is output, the time code signal detecting unit is operated. After obtaining the time information based on the detected time code signal, the operation of the time code signal detecting means is stopped, and the time measured by the time measuring means is corrected based on the time information obtained from the time code signal. And a control circuit for outputting an hour signal based on the corrected time of the clock means when the correction request signal is input.

In the invention according to claim 7 of the present application, the desired time is changed according to the time required from the previous operation of the time code signal detecting means to the obtaining of the time information.

The invention according to claim 8 of the present application displays the current time, outputs a correction request signal at a desired time,
A time display unit for correcting the time by the hour signal, a time code signal detecting means for detecting the time code signal, a time measuring means for performing a timekeeping operation based on time information obtained from the time code signal, and the correction request Operating the time code signal detecting means in response to the output of the signal and outputting an hour signal to the time display unit based on the clock time of the clock circuit, and detecting the detected time code after the output of the hour signal is completed. Control means for acquiring time information from the signal, thereafter stopping the operation of the time code signal detection means, and correcting the time measured by the time measurement means based on the time information obtained from the time code signal. .

[0027]

1, a time information receiving apparatus 1 includes an antenna 214, a long-wave receiver 215, a power control circuit 2 for controlling the power of the long-wave receiver 215, a crystal oscillator 3 for outputting a one-second clock signal, and a CPU; It comprises a control circuit 4 and the like, which are composed of a ROM, a RAM and the like and control various operations. The antenna 214 and the long wave receiver 215 constitute a time code signal detecting unit. The control circuit 4 has an internal clock 4a and a timer 4b which constitute time measuring means in its internal RAM.
The count is updated using the one-second clock signal output from the crystal oscillator 3 as an interrupt signal. The power supply control circuit 2, the crystal oscillator 3, and the control circuit 4 constitute control means. The same components as those shown in FIGS. 4 and 5 are denoted by the same reference numerals. That is, in this example, the time display unit,
As the display drive unit, a conventional one that corrects the time based on the hour signal is used as it is. Note that the time display unit 101 and the display drive unit 103 constitute a time display unit.

Next, the operation will be described with reference to FIG. Here, an example in which the time is corrected using the time signal of 7:00 am will be described. Note that a time signal other than 7:00 am may be used. It is also assumed that all circuits in the time information receiving apparatus 1 are in the initial state immediately after the power is turned on or reset.

During normal hand operation, the control circuit 111 in the display driving unit 103 updates the time of the internal clock 111a based on the output of the crystal oscillator 112, and outputs a pulse to the clock driver 113 every 30 seconds. Clock driver 113
Outputs a hand movement signal to the time display unit 101 based on this pulse, and updates the display of the time display unit 101 for 30 seconds.

When the time counted by the internal clock 111a in the control circuit 111 reaches 6:59:45 am (step 2)
a), the control circuit 111 outputs a correction request signal to the time information receiving device 1 (step 2b). That is, a correction request signal is output to the time information receiving device 1 15 seconds before the correction time.

The control circuit 4 in the time information receiving apparatus 1 in the initial state starts the timer 4b in response to the correction request signal input from the display drive unit 103 (step 2c).

The control circuit 4 updates the count of the timer 4b using the one-second clock signal output from the crystal oscillator 3 as an interrupt signal. When the count value becomes a value corresponding to 23 hours and 55 minutes, that is, the display drive unit The time measured by the internal clock 111a in 103 is 6:54:04 AM on the next day.
At 5 seconds (step 2d), the longwave receiver 215 is operated to receive and decode the time code signal, detect time information from the time code signal, and, based on the detected time, the internal time information in the time information receiving apparatus 1. The clock time of the clock 4a and the generation timing of the one-second clock signal of the crystal oscillator 3 are corrected (steps 2e, 2f, 2g).

When the timer 4b updates the count, if the count value has not reached a value corresponding to 23 hours and 55 minutes, the control circuit 4 immediately enters the HALT mode (stop mode) and consumes power. (Step 2h).

After correcting the clock time of the internal clock 4a and the generation timing of the one-second clock signal of the crystal oscillator 3 based on the time information detected from the time code signal,
The operation of the long wave receiver 215 is stopped (step 2i) to save power, and the control circuit 4 stores the count value of the timer 4b at this time in its internal RAM (step 2j).

In such a state, that is, in a state where the clock time of the internal clock 4a in the time information receiving device 1 is corrected based on the time information detected from the time code signal, the clock of the internal clock 111a in the display drive unit 103 is measured. 6 am again
When the display driving unit 103 outputs the correction request signal again at time 59:45 (step 2k), the control circuit 4 stores the count value of the timer 4b at this time in the RAM therein (step 2m), Thereafter, the timer 4b is reset, and the count is updated again using the one-second clock signal output from the crystal oscillator 3 as an interrupt signal (step 2).
n).

The time information receiving device 1 outputs an hour signal to the display drive unit 103 when the clock time of the internal clock 4a first reaches the hour after the correction request signal is output (step 2p). The display driver 103 corrects the display time according to the hour signal. That is, the internal clock 111 in the display driving unit 103 is based on the clock time of the internal clock 4a corrected based on the time information detected from the time code signal.
Correct the clock time of a. This has the same effect as correcting the clock time of the internal clock 111a in the display drive unit 103 based on the time information detected from the time code signal, and allows accurate time correction. Therefore, it is possible to solve the problem of erroneous correction due to erroneous detection of a time signal, sudden reception failure, and hence correction failure, and reliability of operational stability due to general broadcast waves. The time display on the time display unit 101 is corrected by the correction of the internal clock 111a.

When the output of the hour signal ends (step 2)
p), the control circuit 4 compares the count value of the timer 4b when the operation of the long wave receiver 215 is stopped with the count value of the timer 4b when the correction request signal is output, and the difference is not less than one minute. (Step 2q), the operation start timing of the next long wave receiver 215 is delayed by one minute (step 2r). Conversely, when the correction request signal is output while the long wave receiver 215 is operating, the long wave receiver 215
Is terminated, and the operation start timing of the long wave receiver 215 is advanced by one minute, for example, up to 30 minutes.
As described above, if the time required until the reception state is good and the time information is obtained is short, the time from obtaining the time information by increasing the desired time to outputting the hour signal is shortened to increase the time information. The accuracy of the hour signal is prevented from deteriorating by shortening the period in which the accuracy is degraded by noise or the like. Conversely, if the reception state is poor and the time is long, the desired time can be shortened to extend the time code signal detection operation. Thus, time information can be reliably obtained.

As described above, the time displayed on the time display unit, whose display time is corrected by the conventional hour signal such as a radio time signal, can be corrected based on the time information obtained from the time code signal. Therefore, the time display unit already installed can be used as it is, and the time can be corrected with high accuracy.

In the above example, the operation start timing of the long wave receiver 215 in the time information receiving apparatus 1 is defined based on the count value of the timer 4b. May be started. In this case, the internal clock 4a in the time information receiving device 1 is based on the time information obtained from the long wave receiver 215.
When the next correction request signal is generated,
Based on the time measured by the internal clock 4a, the display driving unit 103
The clock time of the internal clock 111a is corrected. After this correction, the longwave receiver 215 is operated again to correct the time measured by the internal clock 4a in the time information receiving device 1. In this example, since the timer 4b can be omitted, the configuration can be simplified.

The long-wave receiver 21 for detecting time information
Reference numeral 5 may be for receiving a time information medium other than the long-wave standard radio wave, and the signal medium may be wired or wireless. Therefore,
For example, the time information may be detected from a telephone line.

A mechanical contact driven by a cam or the like may be provided on the time display unit 101, and a signal output in response to opening and closing of the contact may be used as a correction request signal.

As shown in FIG. 3, instead of the timer 4b, a counter circuit (constituting counter means) 5 for counting the output of the crystal oscillator 3 and the count value of the counter circuit 5 are set to a desired value. A condition judging circuit 6 (constituting a judging means) composed of a comparing circuit or the like for comparison may be provided. The operation in this case will be described. The counter circuit 5 is operated by the input of the correction request signal, and the condition determination circuit 6 makes the count value of the counter circuit 5 reach a desired value (for example, a value corresponding to 23 hours and 55 minutes). When the long wave receiver 21
5 to the control circuit 4. The control circuit 4 operates the long wave receiver 215 according to this output. Hereinafter, it operates similarly to the above-mentioned example. In this case, the timer 4b in the control circuit 4
Can be omitted, so that the load on the control circuit 4 can be reduced. Further, since the control circuit 4 can be in the stop mode until the condition determination circuit 6 generates an output, power can be saved.

[0043]

According to the present invention, the control means detects a time code signal from a point in time when a desired time elapses from the input of a correction request signal from the outside and obtains time information. Is stopped, and the clock time of the clock means is corrected based on the time information obtained from the time code signal, and when the next correction request signal is input from the outside, the clock time is corrected based on the clock time of the corrected clock means. Outputs an hour signal. Therefore, an hour signal can be output based on time information obtained from the time code signal when the correction request signal is input. Therefore, it is possible to solve the problems of erroneous correction due to erroneous detection of a time signal, sudden reception failure and hence correction, and stability of operation stability due to general broadcast waves. Further, since the time code signal is not always detected, power saving can be achieved.

The control means includes a counter means for starting counting after the correction request signal is inputted, and a judgment for outputting a reaching signal when the count value of the counter means reaches a value corresponding to the desired time. Means and a stop mode until the determination means outputs the arrival signal. When the arrival signal is output, the time code signal detection means is operated, and the time information is detected based on the detected time code signal. When the operation of the time code signal detecting means is stopped after obtaining the time, the time of the time measuring means is corrected based on the time information obtained from the time code signal, and the next correction request signal is input from the outside. And a control circuit for outputting an hour signal based on the time measured by the corrected time measuring means, so that in addition to the above-described effects, further power saving is achieved. Achieved.

The desired time is changed according to the length of time from when the operation of the time code signal detecting means stops until the next correction request signal is input from the outside.
For example, if the reception time is good and the time required to obtain the time information is short, the desired time is extended to shorten the time from obtaining the time information to outputting the hour signal, thereby reducing the accuracy of the time information. To prevent the accuracy from deteriorating.On the other hand, if the reception condition is poor and the time is long, the desired time can be shortened so that the time code signal detection operation can be lengthened and the time information can be reliably obtained. Can be done.

The control means detects the time code signal in response to the input of the correction request signal and outputs an hour signal based on the time counted by the timer circuit. After the output of the hour signal, the detected time code signal is output. From the time code signal detection operation is stopped, and the time measured by the clock means is corrected based on the time information obtained from the time code signal. Counting becomes unnecessary, and operation can be simplified and power consumption can be reduced.

A time information receiving apparatus such as the one described above displays a current time, outputs a correction request signal at a desired time, and corrects the time by an hour signal. When used in combination with a time display unit that corrects the display time using the hour signal, the same effect as described above is achieved, and the time display unit that corrects the display time using an hour signal such as a conventional radio time signal Can be performed using the time information receiving device as described above. Therefore, the time display unit already installed can be used as it is, and the time can be corrected with high accuracy.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of FIG. 1;

FIG. 3 is a block diagram showing another embodiment of the present invention.

FIG. 4 is a block diagram of a conventional timepiece with a time correction function.

FIG. 5 is a block diagram of a conventional timepiece with a time correction function.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Time information receiving device 215 Time code signal detection means 2, 3, 4 Control means 4 Control circuit 4a Clocking means 5 Counter means 6 Judgment means 101, 103 Time display means

Claims (8)

[Claims] A time code signal detecting means for detecting a time code signal; a time measuring means for performing a time measuring operation based on time information obtained from the time code signal; The time code signal detecting means is operated from a point in time when a desired time has elapsed, and after obtaining time information based on the detected time code signal, the operation of the time code signal detecting means is stopped, and the time code signal is obtained from the time code signal. Control means for correcting the timekeeping time of the timekeeping means based on the time information, and when the next correction request signal is input from the outside, outputting a positive time signal based on the timekeeping time of the corrected timekeeping means. A time information receiving device, comprising: 2. The control means according to claim 1, wherein said control means starts counting after said correction request signal is inputted, and said control means is provided when a count value of said counter means reaches a value corresponding to said desired time. And a stop mode until the determination means outputs the arrival signal. When the arrival signal is output, the time code signal detection means is operated to detect the arrival time. After the time information is obtained based on the code signal, the operation of the time code signal detecting means is stopped, and the time measured by the time measuring means is corrected based on the time information obtained from the time code signal. And a control circuit for outputting an hour signal based on the time measured by the corrected time measuring means when the correction request signal is input. Information receiver. 3. The desired time according to claim 1, wherein the desired time changes in accordance with a length of time from when the operation of the time code signal detecting means stops until the next correction request signal is input from outside. A time information receiving apparatus, comprising: 4. A time code signal detecting means for detecting a time code signal, a time measuring means for performing a time operation based on time information obtained from the time code signal, and in response to an external correction request signal input Activating the time code signal detection means and outputting an hour signal based on the clock time of the clock circuit, acquiring time information from the detected time code signal after the output of the hour signal is completed, and then acquiring the time information A time information receiving apparatus comprising: a control means for stopping the operation of the code signal detecting means and correcting the time measured by the time measuring means based on the time information obtained from the time code signal. 5. A time display means for displaying a current time, outputting a correction request signal at a desired time, and correcting the time by an hour signal, a time code signal detecting means for detecting a time code signal, A clock means for performing a clock operation based on the time information obtained from the code signal; and operating the time code signal detection means from a point in time when a desired time has elapsed since the correction request signal was output. The operation of the time code signal detecting means is stopped after obtaining the time information based on the time information, and the time measured by the time measuring means is corrected based on the time information obtained from the time code signal. Control means for outputting an hour signal to the time display means based on the corrected time of the time measuring means when the correction request signal is output. Clock with time correction function. 6. The control means according to claim 5, wherein said control means starts counting after said correction request signal is inputted, and said control means is provided when a count value of said counter means reaches a value corresponding to said desired time. And a stop mode until the determination means outputs the arrival signal. When the arrival signal is output, the time code signal detection means is operated to detect the arrival time. After the time information is obtained based on the code signal, the operation of the time code signal detecting means is stopped, and the time measured by the time measuring means is corrected based on the time information obtained from the time code signal. When a request signal is input,
And a control circuit for outputting an hour signal based on the time measured by said time measuring means. 7. The apparatus according to claim 5, wherein the desired time changes according to a length of time from when the operation of the time code signal detecting means stops until the next correction request signal is input. A clock with a time correction function, characterized in that there is. 8. A time display means for displaying a current time, outputting a correction request signal at a desired time, and correcting the time by an hour signal, a time code signal detecting means for detecting a time code signal, A clock means for performing a clock operation based on time information obtained from the code signal; and operating the time code signal detecting means in response to the output of the correction request signal, and displaying the time based on the clock time of the clock circuit. Output the hour signal to the unit, obtain the time information from the detected time code signal after the end of the output of the hour signal, then stop the operation of the time code signal detection means, and obtain the time code signal. And a control means for correcting the time measured by the time measuring means based on the time information.