JP2003324662A - Control signal transmission system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that three detection terminals of three systems of a line 1, a line 2, and a line 3 per one D terminal and a plurality of signal lines to be connected with them are required. <P>SOLUTION: The control signal transmission system is so constituted that the control signal of the D terminal 1 for transmitting the control signals from a plurality of control signal lines in accordance with broadcast forms is transmitted to the detection terminal 3 on the receiving side of BS digital broadcast or the like. The system is provided with a high speed changeover switch 2 for changing over a plurality of the control signal lines and a control means 4 for controlling the high speed changeover switch 2. The control means 4 can convert the signals of a plurality of the control signal lines to a signal form of one system in time series with a time-sharing system by changing over the high speed changeover switch 2 and can detect it with one detection terminal 3. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control signal transmission system for receiving each format signal using a so-called D terminal on the BS broadcast receiving side and using it as a control signal.

[0002]

2. Description of the Related Art For example, when a receiver such as a BS digital broadcast is connected to another device, a D terminal is used. FIG. 5 shows a control signal transmission system using the D terminal. In the figure, 1 is a D terminal, and this D terminal 1 is Y, Cb of a video signal.
/ Pb, Cr / Pr, screen size, signal form (frequency), signal scanning line form (i: interlaced signal,
p: Progressive signal) control signal lines (line 1, line 2, line 3) are provided, and the control signal lines are connected to the detection terminals 3a, 3b, 3c.

In the case of the BS digital receiver, it is assumed that the signal content is changed on the broadcast side depending on the broadcast mode even if the channel is the same. For example, a high-definition signal (1125i signal) is currently being broadcast, but subsequent broadcasts are switched to the conventional NTSC signal (525i). In this case, the device connected to the BS digital broadcast receiver can smoothly switch if it is notified that the broadcast mode has changed. At such time, the control signal from this control signal line is referred to.
For example, when all three control signals are used, line 1, line 2 and line 3 are detected terminals 3a and 3 respectively.
It is necessary to connect to b and 3c.

Normally, line 1, line 2, and line 3 are
The signals are selected in the mode according to the table of FIG. For example, in the case of a p signal of 525 scanning lines and a screen size of 4: 3 letterbox signal, the discrimination voltages of line 1, line 2, and line 3 are line 1: 0 as shown in FIG.
V, line 2: 5V, line 3: 2.2V. By detecting this information signal, for example, in CTV, mode switching is performed according to these control signals.

[0005]

In the conventional method as described above, as a mounting, three detection terminals are required for one D terminal, the number of detection terminals is large, and they are connected. There was a problem that the signal lines would be huge.

In addition, since one line D, three lines of line 1, line 2, and line 3 detection terminals are required, the number of detection terminals is insufficient for the D terminal to be mounted. It may be excessive, but add a new detection terminal so that excess or deficiency does not occur, or
It becomes necessary to reselect the component having the detection terminal.

The present invention has been made to solve the above problems, and an object thereof is to reduce the total number of detection terminals of these control signal lines (line 1, line 2, line 3). .

[0008]

In the control signal transmission system according to the present invention, on the receiving side of BS digital broadcasting or the like, the control signal of the D terminal for outputting control signals from a plurality of control signal lines according to the broadcasting mode is provided. A high-speed changeover switch for transmitting to the detection terminal, which switches the plurality of control signal lines, and a control means for controlling the high-speed changeover switch, wherein the control means changes the high-speed changeover switch. Converts the signals of multiple control signal lines into a single time-series signal format using the time division method,
It is characterized in that it can be detected by one detection terminal.

Further, in the above control signal transmission system, the control signals of a plurality of control signal lines of a plurality of D terminals are converted into a time-series single-system signal format by a time division method.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. 1 shows a control signal transmission system according to a first embodiment of the present invention, in which 1 is a D terminal having control signal lines of lines 1 to 3 and 2 is a time division control signal of the control signal lines. Control for outputting to the high-speed changeover switch 2 and the detection terminal 3 a high-speed changeover switch for converting the signal format of the time series into one system, 3 is a detection terminal, and 4 is a divided signal which is a timing for converting the lines 1 to 3 in time series It is a department.

FIG. 3D shows an example of the output waveform of the detection terminal 3 when the three control signals of the D terminal 1 are time-sequentially converted by the high-speed changeover switch 2 in the configuration of FIG. As shown in FIG. 3D, when the identification voltage of the control signal is line 1: 0V, line 2: 5V, line 3: 2.2V, according to the table of FIG. , Progressive signal, letterbox screen with aspect ratio of 4: 3.

In FIG. 3, a vertical dotted line is a division signal which is a timing signal for time series conversion output from the control unit 4.
This divided signal serves as a switching signal for the high-speed changeover switch 2, and this divided signal is added to the detection terminal 3 and also serves as a detection trigger at the detection terminal 3.

The first control signal is continued to line 1, then line 2 and line 3 by the divided signal issued as the timing for converting into the above time series, and also at the detection terminal 3 at the same timing. From the signal shown in FIG. 3 (d), which is converted in time series by the divided signal, the line 1,
It is detected as a signal of line 2 and line 3. Therefore,
The output of the detection terminal 3 determines the broadcast mode, and the device responds to mode switching. When increasing the detection speed, the trigger speed by the divided signal of the control unit 4 may be increased.

As described above, in the present embodiment, since the signals of the three control signal lines can be detected by one detection terminal, the number of detection terminals and signal lines can be reduced, and the circuit can be simplified for wiring. Space is reduced and incorrect wiring is prevented.

Embodiment 2. FIG. 4 shows a control signal transmission system according to the second embodiment of the present invention, which has a plurality of D terminals 1a, 1b, 1c. In this figure, 3
In this example, one D terminal is converted in time series to convert nine control signals into one. Since the signal format conversion method is the same as that in FIG. 1, the description thereof is omitted. It is applicable when there are a plurality of D terminals other than this example.

In the case of time-series conversion, if the total control signals increase, the switching speed increases if the switching completion time is the same, and the time allocated to one control signal decreases. In the detection terminal 3, since the divided signals output as timings for time-series conversion are switched at high speed, the resolution of the detection terminal 3 cannot be adapted and the divided control signals cannot be accurately separated and detected. There is.

On the other hand, if the switching time is fixed,
It may take too much time to complete the total switch operation, and the images may not be switched smoothly.

In that case, the number of time-series conversions is reduced and the number of switches 2 and detection terminals 3 is increased. In this case, there are a plurality of forms shown in FIG.

[0019]

As described above, conventionally, when mounting a D terminal, a plurality of detection terminals were required to detect signals of a plurality of lines which are control signals of the D terminal. According to the above, as a result of time-series conversion of the control signal at the D terminal, the number of detection terminals can be reduced, and accompanying this, the number of signal lines can be reduced at the same time.

Further, even when there are a plurality of D terminals,
It is possible to reduce the total number of detection terminals and control signal lines by time-series conversion of a total control signal having a plurality of systems per D terminal.

[Brief description of drawings]

FIG. 1 is a diagram showing a control signal transmission system according to a first embodiment of the present invention.

FIG. 2 is a chart showing a control signal mode of a D terminal in the present invention.

FIG. 3 is a diagram showing a detection signal after time series conversion according to the first embodiment.

FIG. 4 is a diagram showing a control signal transmission system according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a conventional control signal transmission system.

[Explanation of symbols]

1 D terminal, 1a, 1b,
1c D terminal, 2 high-speed changeover switch for time series conversion,
3 detection terminals, 4 control section.

Claims (2)

[Claims] 1. On the receiving side of BS digital broadcasting, etc.,
What is claimed is: 1. A control signal transmission system for transmitting the control signal of a D terminal for outputting a control signal from a plurality of control signal lines to a detection terminal according to a broadcasting mode, comprising: a high-speed changeover switch for switching the plurality of control signal lines; A control means for controlling the changeover switch, wherein the control means converts the signals of the plurality of control signal lines into a signal format of a time series one system by a time division method by switching the high speed changeover switch, A control signal transmission system characterized by enabling detection at a detection terminal. 2. The control signal according to claim 1, wherein control signals of a plurality of control signal lines of a plurality of D terminals are converted into a time-series single-system signal format by a time division method. Transmission system.