JP2925242B2 - Television receiver with built-in teletext and satellite broadcast receiving circuit - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver (hereinafter abbreviated as a television) incorporating a teletext and satellite broadcast receiving circuit.

2. Description of the Related Art Teletext and satellite broadcasts have become popular, and many televisions with a built-in teletext receiving circuit and televisions with a satellite broadcast receiving circuit have been released. In addition, televisions incorporating both text and satellite broadcast receiving circuits have been released.

Hereinafter, a conventional television with a built-in teletext and satellite broadcast receiving circuit will be described with reference to the block diagram of FIG.

The television with a built-in teletext and satellite broadcast receiving circuit includes a terrestrial television broadcast receiving circuit A, a satellite broadcast receiving circuit B, a switching output circuit C, a selecting circuit D, and a teletext receiving circuit E. Hereinafter, the configuration of each circuit will be described in order.

The terrestrial television broadcast receiving circuit A includes a tuner unit 2 for selecting a necessary channel from an input from an antenna 1 for receiving a terrestrial television broadcast, and an IF unit 3 for performing intermediate processing of a signal from the tuner unit 2. And the signal from the IF unit 3 (VI
F) into a video signal, and a video processing unit 4 for converting the terrestrial television broadcast into a video signal a.

Further, the satellite broadcast receiving circuit B includes a BS converter 6 for converting a signal from a BS antenna 5 for receiving a satellite broadcast, a tuning unit 7 for selecting an arbitrary station from the signal from the BS converter 6,
An IF processing demodulation processing section 8 intermediately processes and demodulates a signal from the tuning section 7 and a video signal processing section 9 which converts a signal from the IF processing demodulation processing section 8 into a video signal. The signal is converted to a signal b and output.

Further, the switching output circuit C includes a video signal a of the terrestrial television broadcast from the terrestrial broadcast reception circuit A and a satellite broadcast reception circuit B.
A switching unit 10 for switching and outputting a satellite broadcast video signal b from the multiplexing unit, a color signal processing unit 11 for extracting a luminance signal and a chrominance signal from the output video signal of the switching unit 10, and a combined output signal of the color signal processing unit 11. Or a video synthesizing unit 21 for synthesizing and outputting an output signal from the teletext receiving circuit E, and a display 2 such as a cathode ray tube (CRT) for displaying a signal from the video synthesizing unit 21.
It consists of two.

The control circuit D also receives a key input request and issues an instruction to switch between reception selection of terrestrial broadcasting, satellite broadcasting, and text broadcasting, an instruction to tune to the tuner 2 and the tuning section 7, and a color signal processing section.
It comprises a set microcomputer section 13 for instructing color signal adjustment to 11 and a key input section 14 for making a key input request to the set microcomputer section 13.

Further, the teletext receiving circuit E performs sampling error correction of the teletext signal from the input video signal and determines the presence / absence of the teletext signal, and a selection error signal d from the set microcomputer unit 13. A CPU 15 for performing teletext broadcast reception control processing, a RAM 16 used for arithmetic processing or buffering of the CPU 15, a ROM 17 for storing CPU programs and data, and a character generator (CG for storing fonts for characters used for teletext) ) 18, a video RAM (VRAM) 19 for processing text broadcast signals and storing patternized data, and writing and controlling data from the CPU 15 to the VRAM 19, converting them into RGB signals, and converting them into RGB signals.
And a display control unit 20 for outputting the data to the display control unit 1.

The operation of the television with a built-in teletext and satellite broadcast receiving circuit having the above configuration will be described.

For terrestrial television broadcasting, antenna 1, channel 2, IF
The signal is output as a video signal a through a unit 3 and a video processing unit 4. Similarly, the satellite broadcast is a BS antenna 5, a BS converter 6,
The signal passes through the tuning unit 7, the IF processing demodulation processing unit 8 and the video processing unit 9, and is output as the video signal b. The request signal from the key input unit 14 is processed by the set microcomputer unit 13 and a selection instruction signal c is output to the switching unit 10. The switching operation is performed in the switching unit 10, and the video signal a of the terrestrial television broadcasting or the satellite broadcasting Is passed.

In the case of a normal television broadcast screen, the video signal from the switching unit 10 is displayed on the display 22 via the color signal processing unit 11 and the video synthesis unit 21.

When the character broadcast is selected from the key input unit 14, the display control unit is operated by the selection instruction signal d of the set microcomputer unit 13.
The video synthesizing section 21 is set so that only the teletext display signal is displayed. (Dedicated signal) The video signal from the switching unit 10 is extracted by the sampling error correction unit 12, the teletext signal is sampled, converted into data, error-corrected, fetched as data, further processed by the CPU 15, stored in the buffer in the RAM 16, and displayed. Character code is converted to CG18 pattern and display control unit
20 is written to VRAM 19 via display control 20 and RG is controlled by display control 20.
The display 22 is converted to a B signal, and is
Is displayed as a teletext screen.

As described above, in a conventional television with a built-in teletext and satellite broadcast receiving circuit, the video signal input to the teletext receiving circuit E can always be displayed on the display 22 as a normal television broadcast screen. Is the same as

For this reason, although the television with a built-in teletext and satellite broadcast receiving circuit has two sets of tuner / selection sections of a terrestrial television broadcast and a satellite broadcast, which are ordinary television broadcasts, no teletext is transmitted. When a satellite broadcast is being received, there is a problem that the teletext receiving circuit E cannot perform any processing for capturing the teletext. Teletext broadcasting normally broadcasts programs at a period of 20 seconds. The teletext receiving circuit E has a large capacity memory to improve the usage efficiency of teletext, but these do not function at all during satellite broadcast reception. In addition, it had the problem of significantly impairing the efficiency of teletext broadcasting.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a television receiver with a built-in teletext and satellite broadcast receiving circuit capable of always receiving teletext and improving the use efficiency of teletext information. It is.

Means for Solving the Problems To solve the above problems, a television receiver with a built-in teletext and satellite broadcast receiving circuit according to the present invention comprises a terrestrial television broadcast receiving circuit, a satellite broadcast receiving circuit, and a text broadcast from an input video signal. A teletext receiving circuit having a sampling error correcting unit for performing signal sampling error correction and determining the presence / absence of a teletext signal, a selection circuit for instructing reception selection of terrestrial television broadcasting, satellite broadcasting and teletext, and the selection A first switching unit that switches an output video signal of the terrestrial television broadcast reception circuit and an output video signal of the satellite broadcast reception circuit to a color signal processing circuit and connects the output video signal from the terrestrial television broadcast reception circuit and the text broadcast reception circuit according to an output selection instruction signal of the circuit; And a second switching unit for switching and connecting to the satellite broadcast receiving circuit. A satellite broadcast code table having a code for determining that the satellite broadcast code table is output, and an output selection instruction signal of the selection circuit is determined to be a satellite broadcast reception request by the code of the satellite broadcast code table, and the sampling error correction unit And a control unit for switching the second switching unit to an output video signal of the terrestrial television broadcast receiving circuit when it is determined that there is no text broadcast signal.

Further, a television receiver with a built-in teletext and satellite broadcast receiving circuit according to the second invention is provided with a terrestrial television broadcast priority setting register in the teletext transmitting / receiving circuit according to the first invention, and a control unit of the teletext receiving circuit. In accordance with the terrestrial television broadcast priority signal from the selection circuit, the terrestrial television broadcast priority setting register is set to terrestrial television broadcast priority, and the second switching unit is set to the output video signal of the terrestrial television broadcast reception circuit. The function of switching and fixing is added.

According to the configuration of the first aspect of the present invention, when the selection circuit outputs a satellite broadcast selection instruction signal, the first switching unit and the second switching unit of the video signal dedicated to the teletext receiving circuit are both satellite broadcasting. Switch to the side. Further, the teletext receiving circuit determines from the satellite broadcast code table that the output selection instruction signal of the selection circuit is a satellite broadcast reception request, and the teletext signal is not superimposed on the satellite broadcast video signal in the sampling error correction unit. Is determined, the second switching unit for the video signal dedicated to the teletext receiving unit is switched to the video signal for terrestrial television broadcasting.

According to the configuration of the second invention, the teletext receiving circuit sets the terrestrial television broadcasting priority to the terrestrial television broadcasting priority setting register according to the terrestrial television broadcasting priority signal from the selection circuit, and sets the second switching unit to Switch to the output video signal of the terrestrial television broadcast receiving circuit and fix it.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The same components as those of the conventional example shown in FIG. 3 are denoted by the same reference numerals, and description thereof is omitted.

FIG. 1 is a block diagram of a television with built-in teletext and satellite broadcast receiving circuits according to an embodiment of the first invention.

The television with built-in teletext and satellite broadcast receiving circuit according to the first invention has a configuration in which the video signal a of the terrestrial television broadcast receiving circuit A and the video signal b of the satellite broadcast receiving circuit B are set to the microcomputer shown in FIG. A second switching unit 23, which is switched from the selection instruction signal c of the unit 13 and is connected to the teletext receiving circuit E ', is newly provided. Further, the selection instruction signal d from the set microcomputer unit 13 is transmitted to the teletext receiving circuit E'. A BS code table 24 having a table of codes for determining whether the request is a satellite broadcast request is newly provided, and a selection instruction signal d is provided to the CPU 15 '.
Is determined to be a satellite broadcast reception request by the code in the BS code table 24, and when it is determined by the sampling error correction unit 12 that there is no teletext signal, the second switching unit 23 is switched to the video of the terrestrial television broadcast reception circuit A. A function for switching to signal a is added.

 The operation of the newly added configuration will be described.

When satellite broadcast reception is requested from the key input unit 14, the set microcomputer unit 13 outputs a satellite broadcast reception request selection instruction signal d to the CP.
The video signal is transmitted to U15 and both the switching unit 10 and the switching unit 23 switch the video signal from the terrestrial television broadcast side to the satellite broadcast side. The sampling error correction unit 12 extracts a teletext signal from the switched video signal and performs error correction. CPU section 15
Compares the request code of the selection instruction signal d from the set microcomputer unit 13 with the data in the BS code table 24 to determine that the request is a satellite broadcast request. Further, in the sampling error correction unit 12,
If no teletext signal is detected, the CPU 15 immediately switches the switching unit 23 to a video signal on the terrestrial broadcast side.

As described above, when the reception of the satellite broadcast is selected and the teletext signal is not superimposed on the satellite broadcast, the video signal a of the terrestrial television broadcast is input to the teletext receiving circuit E ′, so that the display 22 is displayed. Even when a satellite broadcast screen is displayed, terrestrial television broadcasts multiplexed with teletext can always be received to update the contents of the buffer in the RAM 16, and the latest information can be displayed immediately when teletext is selected.

Next, an embodiment of the second invention will be described with reference to the block diagram of FIG.

The television with built-in teletext and satellite broadcast receiving circuit of the second invention has the same structure as that of the first invention, and further includes the case where it is known that the teletext is not multiplexed with the satellite broadcast in the teletext receiving circuit E ″. The terrestrial television broadcast priority setting register 25 to be set is added, and the priority setting register 25 is set in the CPU 15 ″ according to the terrestrial television broadcast priority code sent from the set microcomputer unit 13, and the second switching unit 23 is set. The function of switching to and fixing the video signal a of the terrestrial television broadcast is added.

 The operation of the newly added configuration will be described.

When the terrestrial television broadcast priority setting is performed from the input unit 14, the set microcomputer unit 13 transmits a terrestrial television broadcast priority setting code to the CPU 15. When detecting the terrestrial television broadcast priority setting code, the CPU 15 sets the priority register 25,
The switching unit 23 is set so as not to switch to the satellite broadcasting side.

The CPU section 15 receives a selection instruction signal d from the set microcomputer section 13.
When a satellite broadcast request is sent, the code is discriminated from the BS code table 24 and recognized as a satellite broadcast.

By providing the terrestrial television broadcast priority setting register 25 in this manner, the teletext receiving circuit E ″ can always receive the terrestrial television broadcast in which the teletext is multiplexed even when switching to the satellite broadcast. In addition, it is possible to eliminate the time for detecting the teletext at the time of switching to the satellite broadcast, prevent data from being lost during this time, and always provide complete teletext information.

Effects of the Invention As described above, according to the first invention, when a satellite broadcast reception request is received from the selection circuit, a conventional first switching unit and a second video signal switching unit dedicated to a text broadcast receiving unit are provided. Are switched to the satellite broadcast side, and the teletext receiving circuit determines from the satellite broadcast code table that the selection instruction signal is a satellite broadcast reception request, and if the teletext signal is not superimposed on the satellite broadcast video signal, Immediately switches the second switching unit of the video signal dedicated to the teletext receiving unit to the video signal of the terrestrial television broadcasting,
Even when the display is displaying a satellite broadcast screen that does not multiplex text broadcasting, it always receives terrestrial TV broadcasting multiplexed with text broadcasting and can always update text broadcasting information content, users can use text broadcasting In this case, it is possible to obtain an extremely excellent effect that the latest information can be displayed immediately.

According to the second aspect of the present invention, the provision of the terrestrial television broadcast priority register allows the teletext receiving circuit to always display the terrestrial television broadcast even if the display of the television screen is switched to the satellite broadcast. Can receive
It is possible to reduce the time required for the detection of teletext when the satellite broadcast is switched, to prevent data loss during this time, and to provide complete teletext information at all times.

[Brief description of the drawings]

FIG. 1 is a block diagram of a television with a built-in teletext and satellite broadcast receiving circuit in one embodiment of the first invention, and FIG. 2 is a block diagram of a television with a teletext and satellite broadcast receiving circuit in one embodiment of the second invention. FIG. 3 is a block diagram of a conventional television with a built-in teletext and satellite broadcast receiving circuit. A: terrestrial television broadcasting receiving circuit, B: satellite broadcasting receiving circuit, C: switching output circuit, D: selecting circuit, E, E ', E "
... Teletext broadcast receiving circuit, 10... (First) switching section, 15, 1
5 ', 15 "... CPU, 23 ... (second) switching unit, 24 ... BS
Code table, 25: Terrestrial television broadcast priority setting register, a: Video signal of terrestrial television broadcast, b: Video signal of satellite broadcast, c, d ... Selection instruction signal.

Claims (2)

(57) [Claims] A terrestrial television broadcast receiving circuit, a satellite broadcast receiving circuit, and a teletext broadcast receiving circuit having a teletext signal extracted from an input video signal, and an error correction section for performing error correction and determining presence or absence of the teletext signal. Circuit, a selection circuit for instructing reception selection of terrestrial television broadcasting, satellite broadcasting, and text broadcasting, and an output video signal of the terrestrial television broadcasting reception circuit and an output signal of the satellite broadcasting reception circuit according to an output selection instruction signal of the selection circuit. An output video signal is provided with a first switching unit that switches and connects to a color signal processing circuit and a second switching unit that switches and connects to the teletext receiving circuit. A satellite broadcast code table having a code for determining that the output selection instruction signal is a satellite broadcast reception request, and an output selection instruction signal of the selection circuit is It is determined by the code in the satellite broadcast code table that the request is a satellite broadcast reception request, and when it is determined by the sampling error correction section that there is no teletext signal, the second switching section is output from the terrestrial television broadcast reception circuit. Television receiver with built-in teletext and satellite broadcast receiving circuit provided with control unit for switching to video signal. 2. A terrestrial television broadcasting priority setting register is provided in a teletext receiving circuit, and a terrestrial television broadcasting priority setting register is provided in a control unit of the teletext receiving circuit in accordance with a terrestrial television broadcasting priority signal from a selection circuit. 2. A television with a built-in teletext and satellite broadcast receiving circuit according to claim 1, further comprising a function of setting a terrestrial television broadcast priority and switching the second switching unit to an output video signal of the terrestrial television broadcast receiving circuit and fixing the output video signal. Receiver.