JPH08101289A - Electronic clock - Google Patents

Abstract

PURPOSE: To obtain an electronic clock in which a user is not required to reset a correct time when a clock is disordered or stopped due to some cause but a correct time is set automatically at all times. CONSTITUTION: A data channel decoder(DCD) 2 decodes the signal of a data channel from a bit stream signal 6 and a time information data 10, e.g. a Japanese standard time, is obtained from a time signal decoding section 3. A timer section 5, comprising a counter for measuring the time, set the value of the time information data 10 in the counter every time when a timing pulse is inputted from the counter section 4 at a predetermined time interval.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic timepiece used for time display, timer reservation, etc., in data broadcasting transmitted using a satellite broadcasting data channel,
The present invention relates to an electronic timepiece that automatically calibrates time at predetermined time intervals using time information data of time signals transmitted at the same time as various signals.

[0002]

2. Description of the Related Art Currently, electronic products such as TV receivers and video tape recorders (VTRs) use electronic timepieces having a circuit combining a fixed frequency oscillator and a counter for time display and timer reservation. There is.

[0003]

However, since such an electronic timepiece normally uses a commercial power source,
It will be reset after a power failure or when the outlet is unplugged, so the user must set the correct time again. If you have not reset the correct time,
For example, when a timer for recording is reserved in the VTR, there is a problem that the recording is not performed in the correct time zone.

Therefore, by using the battery as a main power source or a backup, such a problem disappears, but a problem arises in that the battery must be periodically replaced. There is also a problem that the user sometimes has to set the correct time in order to correct the secular change due to the accuracy of the fixed frequency oscillator or the like.

So, for some reason the time goes wrong,
An object of the present invention is to provide an electronic timepiece in which, when stopped, the user does not have to reset the correct time and the time is automatically set to the correct time.

[0006]

In order to solve the above-mentioned problems of the prior art, the present invention provides a data channel for inputting a bit stream signal of satellite broadcasting, decoding the data channel signal and outputting packet data. A decoder, a time signal decoding unit that inputs the packet data, extracts and decodes a time signal and outputs time information data, and inputs a first clock and counts the timing pulse at a predetermined time interval. It comprises a counter unit for outputting and a timer unit for inputting a second clock to count the time and counting the time, and for inputting the timing pulse, setting the time to the value of the time information data. The electronic timepiece is provided.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Recently, a data broadcast for transmitting various digital signals such as a facsimile signal, a telesoftware signal, a still image signal, a character signal, and a telemusic signal by utilizing a data channel of satellite television (TV) broadcasting. It is standardized. In this data broadcasting, in addition to signals for original services such as a facsimile signal in a data channel, for example, presentation timing control of images, voices, characters, etc. in a still image signal, and reproduction time control in a telemusic signal are controlled. , A time signal is transmitted for synchronous reproduction control with video and audio.

Therefore, the present invention provides an electronic timepiece having a function of automatically calibrating the time at a predetermined time interval by using the time information data of the time signal in the data broadcasting.

First, a time signal transmitted by data broadcasting will be briefly described. Standard TV broadcasting of satellite broadcasting (N
In the TSC system, voice is transmitted on multiple subcarrier digital channels, and 2
There is room for transmission between 24 Kbps and 1760 Kbps, and this is called a data channel. High definition TV broadcasting (MUS
In the E) method, voice is transmitted within the vertical blanking period, and similarly, there is a data channel of 112 Kbps to 1184 Kbps.

The above digital channel is
One frame consists of 2048 bits in the standard system and 1350 bits in high definition TV broadcasting, and each frame period is 1 msec, that is, 1000 frames is 1 second.

As a transmission method of data transmitted as data broadcasting, a fixed length packet multiplexing method in a data channel area is used. The packet consists of a header part and a data part, and the packet length is 288 bits.
The nine frames of the digital channel are used as a unit to form a superframe, and as shown in FIG. 4, packets are diagonally multiplexed in the data channel area in units of the superframe. Further, a unit of 4 superframes (36 frames) is called a master frame, which is a unit indicating the timing of mode switching or data suppression.

The time signal transmitted in this data channel has a fixed length of 19 bytes, and its signal structure is as shown in FIG.

Next, one embodiment of the electronic timepiece of the present invention will be described with reference to the accompanying drawings. 1 is a block diagram showing an embodiment of an electronic timepiece according to the present invention, FIG. 2 is a block diagram showing an example of the configuration of a counting section, and FIG. 3 is a block diagram showing an example of the configuration of a timer section.

In FIG. 1, a tuner section 1 selectively receives a satellite broadcast and outputs a bit stream signal 6 thereof. A data channel decoder (DCD) 2 decodes a data channel from a bit stream signal 6, and packet data 7, a master frame pulse (first clock) 8 indicating the beginning of a master frame, and a frame pulse indicating the beginning of a frame. (Second clock) 9 is output.

The time signal decoding unit 3 extracts and decodes the packet data of the time signal from the packet data 7, and according to the purpose of the electronic timepiece, the modified Julian date, Coordinated Universal Time,
All or part of the time information data such as Japan Standard Time is output as the time information data 10.

The counter section 4 compares a preset value with a count value of a counter which uses the master frame pulse 8 as a clock, and outputs a timing pulse 11 at a constant time interval.

The counter section 4 will be described with reference to FIG. In FIG. 2, the counter 12 counts up using the master frame pulse 8 as a clock. A certain value can be set in advance in the set value buffer 13. The comparator 14 compares the value of the set value buffer 13 with the output of the counter 12, and outputs the timing pulse 11 if the values are the same. The counter 12 is reset by the timing pulse 11.

As described above, the master frame has 3
Since there are 6 frames (1 frame period is 1 msec) and the master frame pulse is generated every 36 msec, for example, when the set value of the set value buffer 13 is 1000, the timing pulse 11 is output at 36 second intervals. It will be.

In FIG. 1, a timer unit 5 is composed of a counter for obtaining time data using a frame pulse 9 as a clock, and when a timing pulse 11 is input, the time information data 10 of a time signal transmitted by data broadcasting. Is set to the value of. In the data broadcasting standard, the value of the time signal sent is the start time (current time plus 72 msec) of the master frame that is two times ahead of the time signal, so a timing pulse is generated. Then, by setting the time signal by the master frame pulse which is two ahead, the accurate time can be obtained.

The timer section 5 will be described with reference to FIG. In FIG. 3, the "1000" counter 15 is a 1000-ary counter that uses the frame pulse 9 as a clock, and when the timing pulse 11 is input, the millisecond 10a of the Japanese standard time of the time information data is set.
Further, the "60" counter 16 is a 60-ary counter that uses the carry output of the "1000" counter 15 as a clock, and when the timing pulse 11 is input, the second 10b of the Japanese standard time is set.

Similarly, the "60" counter 17 displays "6".
0: Carry output of counter 16 as clock 60
When the timing pulse 11 is inputted, the minute counter 10c of Japan Standard Time is set. The "24" counter 18 is a 24-bit counter that uses the carry output of the "60" counter 17 as a clock, and when the timing pulse 11 is input, 10d at the Japanese standard time is set.

Therefore, each time the timer unit 5 inputs the timing pulse 11 (in this embodiment, at 36-second intervals), the time data being clocked is changed to the Japanese standard time of the time signal sent by data broadcasting. Since it is calibrated, it is possible to always provide an accurate time.

The above-described embodiment is an electronic timepiece that presents hours, minutes, and seconds of Japan Standard Time, but the year, month, and day of Japan Standard Time obtained from the time information data of the time signal is used according to the application. ， It can be an electronic timepiece that presents the week or Coordinated Universal Time. Further, it goes without saying that the clock of the timer unit 5 may be the output of the fixed frequency oscillator instead of the frame pulse, or the clock of the counter unit 4 may be other than the master frame pulse.

[0024]

As described in detail above, the electronic timepiece of the present invention does not require the user to reset the correct time when the time goes wrong or is stopped for some reason, and the electronic timepiece can be set at predetermined time intervals. Since the time is automatically calibrated, there is an extremely excellent practical effect that the accurate time can always be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an electronic timepiece according to the present invention.

FIG. 2 is a block diagram illustrating a configuration example of a counting unit.

FIG. 3 is a block diagram showing a configuration example of a timer unit.

FIG. 4 is a diagram for explaining a fixed length packet multiplexing system.

FIG. 5 is a block diagram of a time signal transmitted on a data channel.

[Explanation of symbols]

 2 data channel decoder (DCD) 3 time signal decoding unit 4 counter unit 5 timer unit 6 bit stream signal 7 packet data 8 master frame pulse (first clock) 9 frame pulse (second clock) 10 time information data

Claims (3)

[Claims] 1. A data channel decoder for inputting a satellite broadcast bit stream signal, decoding a data channel signal and outputting packet data, and time information for extracting and decoding a time signal by inputting the packet data. A time signal decoding unit that outputs data, a counter unit that inputs a first clock and outputs a timing pulse at a predetermined time interval by counting, and a second clock input and counts a time by counting An electronic timepiece comprising a timer section for setting time to a value of the time information data when clocking and inputting the timing pulse. 2. The electronic timepiece according to claim 1, wherein the first clock is a master frame pulse output from the data channel decoder. 3. The electronic timepiece according to claim 1, wherein the second clock is a frame pulse output from the data channel decoder.