KR940007995B1 - Automatic visual control device of tv - Google Patents

Abstract

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Description

Automatic Visual Control and Method of TV

1 is a circuit configuration diagram of a television having a conventional teletext function.

2 is a block diagram of an automatic visual adjustment apparatus of a television having a teletext function according to the present invention.

3 is an exemplary waveform diagram of horizontal synchronization and cancellation signals.

4 is an exemplary waveform diagram of teletext data.

5 is an explanatory diagram of a teletext data line structure.

6 is an explanatory diagram of an application system data structure.

7 is a control flowchart diagram for carrying out the present invention.

* Explanation of symbols for main parts of the drawings

1 antenna 2: digital tuner

3: audio intermediate frequency separation circuit 4: video intermediate frequency separation circuit

5: low frequency amplifier 6: speaker

7: chroma circuit 8: teletext circuit

15: remote control 18: preamplifier

30: broadcasting station time data generating means 30A: voltage controlled oscillator

30B: Phase difference detector 30C: Loop filter

30D: Amplifier 30E: Pilot Signal Detector

30F: Monostable Multivibrator 30G: Endgate

40: micom 50: RAM

The present invention relates to an automatic visual adjustment apparatus and method for a television for adjusting the microcomputer time and the broadcasting station time in a television having a teletext function.

A conventional television having a teletext function is constructed as shown in FIG. 1. When the television is powered on, a signal received through the antenna 1 is tuned by the digital tuner 2 so that a video signal and an audio signal are received. The signals are mixed and provided to the audio intermediate frequency separation circuit 3 and the video intermediate frequency separation circuit 4.

The voice signal is applied to the low frequency amplifier 5 by the voice intermediate frequency separation circuit 3 and then amplified and output to the outside through the speaker 6.

On the other hand, the video intermediate frequency signal separated and output from the video intermediate frequency separation circuit 4 is simultaneously applied to the chroma circuit 7 and the teletext circuit 8, but when receiving a general television broadcast signal, 8) does not work, but only the chroma circuit 7 operates so that each color signal R1, B1, G1 is provided to one side contact A of the switching section 9.

At this time, the switching unit 9 is short-circuited to the one-side contact A by the control signal CTL (fast blanking signal) generated therefrom when the teletext circuit 8 does not operate when listening to the general broadcast, and thus the color signals R1 and B1. , G1) is provided to the color brown tube driver 10.

Accordingly, the color CRT driver 10 amplifies the color signals R1, B1, and G1 by the respective amplifiers 10R, 10B, and 10G therein, and then the amplified color voltage signals R, B, and G) is displayed on the color brown tube 11 to display a television broadcast screen.

In the above, the horizontal synchronous signal output from the image intermediate frequency separation circuit 4 and passed through the horizontal and vertical synchronous signal generators 12 is detected by the horizontal synchronous detector 13, and the vertical synchronous signal is detected by the vertical synchronous detector 14 Is detected and then provided to the color tube (11).

On the other hand, when the user wants to watch teletext information other than general television broadcasting, when the user presses the teletext key (not shown) on the remote control 15, the transmitting infrared lamp 16 has a predetermined frequency. A signal is generated and transmitted to the light receiving lamp 17.

At this time, the signal corresponding to the teletext information received by the light receiving lamp 17 is amplified by the preamplifier 18 and provided to the microcomputer 19.

Then, the microcomputer 19 recognizes this and outputs the teletext control signal TXT to the teletext circuit 8.

When the teletext control signal TXT is input from the microcomputer 19 to the teletext circuit 8 in this manner, the teletext circuit 8 processes the teletext data contained in the video intermediate frequency (composite video signal) and The color signals R2, B2, and G2 are generated and applied to the other contact point B of the switching unit 9.

In addition, since the control signal CTL is generated in the teletext circuit 8 to short-circuit the switching unit 9 to the other contact point B, the color signals R1, B1, and G1 of the chroma circuit 7 are blocked. Color signals R2, B2, and G2 output from the teletext circuit 8 are sequentially transmitted to the color brown tube 11 through the other contact point B of the switching unit 9 and the color brown tube driver 10, thereby providing teletext information. Can be displayed on the color brown tube (11).

On the other hand, in the circuit shown in FIG. 1, the clock in the microcomputer 19 itself is processed by software for time information. The time information is stored in the RAM 20, and then the color-brown tube 11 is used. Is displayed.

However, in this conventional technology, the clock function in the microcomputer itself is a kind of counter using a clock, which causes errors due to the external temperature or the surrounding environment, and the user has to set the clock correctly even when the power is turned off. There was a problem.

Accordingly, the present invention has been made to solve such a conventional problem, and when the clock of the microcomputer has a hardware error, the automatic time adjustment apparatus and method of the television for automatically matching the clock of the microcomputer with the time transmitted from the broadcasting station. The purpose is to provide.

The present invention for achieving the above object can receive a general television broadcast signal and a teletext information signal transmitted from a broadcasting station, and as an automatic time adjustment circuit of a television having a RAM for storing standard time data when performing the teletext mode It is operated by a chip enable signal generated every three months in the teletext mode, and generates a broadcast station time data generating means for outputting the broadcast station time data included in the teletext information, and a chip enable signal every three months. In other words, it compares the time data of the broadcasting station with the standard time data stored in the RAM. If the standard time is wrong, the microcomputer automatically stores and sets the broadcasting time in the RAM.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a circuit configuration diagram for automatically setting the time displayed on a television (or video tape recorder) having a teletext function according to the present invention. Detailed description thereof will be omitted and only different portions will be described.

In FIG. 2, the portion indicated by the dotted line is the broadcasting station time data generating means 30, which is a chip enable signal generated by the microcomputer 40 (this can be generated once every three months, A composite image including a voltage controlled oscillator 30A which is operated by a software program to be generated once) and generates a horizontal synchronous frequency (15.75KHz) signal, and the teletext information output from the image intermediate frequency separation circuit 4. And a phase difference detector 30B for detecting a phase difference between the signal and the horizontal synchronized frequency signal generated by the voltage controlled oscillator 30A.

The broadcasting station time data generating means 30 further includes a loop filter 30C for filtering signals other than the corresponding frequency from the output signal of the phase difference detector 30B, and an amplifier 30D for amplifying the signal filtered by the loop filter 30C. And a pilot detector 30DE for detecting a pilot signal included in the signal amplified by the amplifier 30D, and outputting a high state signal during a period (50.286 μsec) in which the detected pilot signal is inputted. It further includes a monostable multivibrator 30F and an AND gate 30G which outputs data to the microcomputer 40 only during the data period of the teletext in which the high state signal is output. In the above, the voltage controlled oscillator 30A, the phase detector 30B, the loop filter 30C, and the amplifier 30D are operated by a phase locked loop (PLL) circuit. The RAM 50 preferably stores predetermined standard data that the microcomputer 40 uses for teletext to set broadcast station time.

Referring to the operation of the present invention configured as described above, when the teletext signal is transmitted from the composite video signal (see FIG. 4), which is the video intermediate frequency signal of the television, time information is extracted from the data and synchronized with the internal clock of the microcomputer 40. do.

In this case, the broadcasting station time data generating means 30 removes only the synchronous data (see FIG. 4) from which the synchronization signal and the color burst signal shown in FIG. 3 are removed from the composite video signal output from the video intermediate frequency separation circuit 4. Output

Then, the microcomputer 40 sets the clock in the microcomputer itself to this information in the case of the time information that receives the signal and confirms that it is time information. This will be described in more detail.

In FIG. 2, the video intermediate frequency signal output from the video intermediate frequency separation circuit 4 includes a video signal and a teletext data signal for a television. The user operates the remote controller 15 to provide teletext information. When the teletext key is pressed to receive, the microcomputer 40 generates a chip enable signal once every three months, which is programmed in software.

First, when the chip enable signal is output from the microcomputer 40 in a high state, the voltage controlled oscillator 30A, the phase difference detector 30B, the loop filter 30C, and the amplifier 30D form a phase locked loop. This is synchronized with the horizontal synchronization signal of the composite video signal.

At this time, the frequency of the voltage controlled oscillator 30A oscillates at 15.75 KHz, thereby performing a synchronous operation with the composite video signal of the television.

When this is synchronized, the pilot detector 30E detects one pulse at the time when clock synchronization starts, and this signal is applied to the monostable multivibrator 30F. Here, the time constant of the monostable multivibrator 30F is 50.286 µsec, which is a data period, and a high state signal is output while the time data is leaked.

The high signal thus output is applied to one input terminal of the AND gate 30G, and the teletext data of the composite video signal output from the image intermediate frequency separation circuit 4 is input to the other input terminal thereof.

In this case, when the AND gate 30G outputs only pure time information and provides the microcomputer 40 to the microcomputer 40, the microcomputer 40 performs a time setting operation by software. It demonstrates with reference to a chart.

Before describing the flowchart of FIG. 7, the data line of FIG. 5 is first described. The data line is sequentially divided into 16 bits of clock synchronization CS, 8 bits of byte synchronization BS, and 5 bytes of prefix PREFIX. It consists of a 28-byte data block.

Here, the first 16 bits of the synchronization signal are clock synchronization signals, and " 1 " and " 0 " are alternately repeated, and the first bit is " 1 "

In addition, 17 to 24 bits of the synchronization signal is a framing code and is used as a reference signal for byte synchronization.

The data prefix consists of 5 bytes in the order of P1, P2, P3, CI, and PS. This data packet is protected by ending one "bundle".

Finally, as shown in FIG. 6, the data block is composed of a data group header, a recorder head, and record data. In FIG. 6, the information about time is shown in FIG. Date information), followed by 1 to 14 bytes of time information. Therefore, the microcomputer 40 catches this information and adjusts time.

7 is a flowchart for carrying out the present invention, in which the time counter acts as a clock in the microcomputer 40 and acts as a " mode 1 " (Step 101)

Here, when the time counter reaches three months, one counting signal is generated and provided to the microcomputer 40. (Step 102)

Then, the microcomputer 40 checks whether the power is turned on to the television and keeps checking when the power is not turned on, and monitors whether the power is turned on and the teletext function has been input from the remote control (step 103).

When power is applied to the television and the teletext function is performed, the microcomputer 40 provides a high-speed chip enable signal to the broadcasting station time data generating means 30 through its terminal. (Step 104)

At this time, the broadcasting station time data generating means 30 receives the chip enable signal and provides the above-mentioned time data to the microcomputer 40 (step 105), and the microcomputer 40 receives the data and receives the data group and record. After processing the head group (step 106), it is checked whether the data record content is 3/0 (time information), and if it is not time information, the program returns from step 107 to step 104 to repeat the time. Perform data check.

If the result of the data record determined in step 107 is the time information, the microcomputer 40 fetches the framing time code indicating the existing time from the RAM 50 (step 108) and broadcast station time data generating means 30. In step 109, the inputted time information is compared with the existing time (step 109). If not, the data is converted so that time data can be set in the time counter (step 110).

When the conversion of the data is completed, the microcomputer 40 performs a "mode 2" which is a mode for erasing its own time and setting the time transmitted from the broadcasting station to set the time in the time counter (steps 111 and 112). After the setting of the time is completed, the microcomputer 40 switches the mode back to " mode 1 " so that the original clock operation can be performed to match the time in the television microcomputer with the broadcasting station (step 113).

As described above, the present invention accurately sets the time every three months by receiving the time information sent from the broadcasting station, and thus, when the power is turned off as in the prior art, it is possible to completely solve the troublesome problem of having to adjust the time again.

Claims (4)

A television apparatus for receiving teletext and broadcast signals, comprising: broadcasting station time data generating means for receiving a teletext signal and separating time data into a microcomputer, and a storage device (RAM) for storing the currently set time data; And control means for comparing the time data from the broadcasting station time data generating means with the current time data stored in the storage device and changing and storing the time data into the broadcasting station time data if different. Visual adjustment device. 2. A phase locked loop (PLL) according to claim 1, wherein the broadcasting station time data generating means receives a composite video signal output from the video intermediate frequency separation circuit 4 of the television apparatus under the control of the control means, and fixes and outputs a synchronous clock. ), A pilot signal detector for detecting a pilot signal of a teletext signal from an output signal of the phase locked loop circuit, and a monostable multi-output for outputting a high potential signal during a teletext data period by a detection signal of the pilot signal detector. And an end gate (30G) for inputting the composite video signal to an image control means while a high potential signal is output from the monostable multivibrator. A first step of counting a time adjustment period, a second step of outputting a control signal to a broadcasting station time data generating means to turn on the television and to perform time adjustment when the time adjustment period time in the first step is reached; A third process of receiving data from the broadcasting station time data generating means by the control signal, comparing the time data from the input data with the time data set in the storage means, and adjusting the time if the result of the comparison in the third process is the same And a fourth step of terminating the operation and otherwise adjusting the current time data with the broadcasting station time data. 4. The method of claim 3, wherein the adjusting of the current time data by the broadcasting station time data in the fourth process comprises: switching the mode of the time counter to the time adjusting mode, and then setting the time of the time counter as the broadcasting station time data. And subsequently switching the mode of the time counter to the operation mode.

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