JP2001346101A - Input changeover device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an input changeover device for a video.audio unit having input terminals that can save trouble of manual switching of inputs. SOLUTION: An input signal detection means 7 sequentially detects the presence of an input signal at each of input signal terminals 1, 2 and 3 and a microcomputer 6 receiving a detecting result of the detection means 7 controls a switch 4 to select the input signal of a terminal whose signal state changes from the absence state to the presence state to be an output signal. When the input signal at the terminal selected as the output signal is lost, the input signal detection means 7 sequentially detects the presence of the input signal at each of the input signal terminals 1, 2 and 3 and the microcomputer 6 controls the SW4 to select the input signal at the other terminal receiving the input signal as the output signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video / audio device having a plurality of input terminals.

[0002]

2. Description of the Related Art In recent years, there are many video / audio devices having a plurality of input terminals, and various types of input signal signal sources have been developed. In such a background, selecting one input signal from among the plurality of input signals is one of the important functions of the device.

[0003] One of the input switching methods is disclosed in Japanese Patent Application Laid-Open No. H11-88785 in order to make the device user-friendly. In this method, the digital signal input is selected when the input of the digital signal and the analog signal is detected, and the analog signal is selected when the input of the digital signal is not detected. It has a configuration.

[0004]

In the above-mentioned device, a circuit of a specific terminal is preferentially selected. Therefore, when a circuit having a higher priority has a signal input and a circuit having a lower priority is selected, a circuit having a lower priority is selected. When a signal needs to be used and a new signal is input, there is a problem that the input must be manually switched.

[0005]

In order to solve the above-mentioned problem, an input switching device according to the present invention uses an input signal detecting means to sequentially detect the presence or absence of an input signal at each input signal terminal, and to detect the presence or absence of an input signal. The signal of the terminal that has changed to a certain state is controlled so as to be selected as an output signal, and when there is no signal input to the terminal selected as the output signal, the input signal detecting means sequentially turns the input signal for each input signal terminal. An input switching device that detects the presence / absence and controls to select another terminal to which a signal is input as an output signal.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention relates to an input switching device having a plurality of input terminals,
Detects the input signal of each terminal, automatically selects and outputs the input terminal where the new input signal is detected, and automatically inputs the signal when no signal is input to the output terminal It is characterized by selecting the other terminal as an output, for example, when connecting a game device and turning on the power while watching TV, or conversely, when ending the game and turning off the power. For example, input switching is automatically performed in such a manner as described above, so that the trouble of having to manually perform input switching can be eliminated.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1, 2 and 3. FIG. As an example, an input circuit of a television is shown.

In FIG. 1, (1), (2) and (3) are input signal terminals, (4) is a switch SW1 for selecting an input signal terminal to be an output signal, and (5) is an input signal terminal to be detected. , (6) is a microcomputer for controlling the aforementioned SW1 and SW2, (7) is a signal detecting means, (8) is presence or absence of an input signal at each signal input terminal,
Input signal terminal selected by SW1 and SW
1 is a storage device for storing the presence or absence of an input signal to the input signal terminal selected by 1. FIG. 1 mainly shows the video signal system, and the audio signal system is omitted.

First, the signal input to each input terminal is SW
1 (4) and SW2 (5). The microcomputer (6) controls the SW2 (5), and the input signal of the selected terminal is input to the signal detection means (7). The presence or absence of an input signal for this terminal is determined by the signal detection means (7), and the result is input to the microcomputer (6) as a signal presence / absence determination signal. SW1 (4) is controlled by the microcomputer (6) under the conditions described below based on the result of comparison with the determination result at the time of the previous determination called from the storage device (8), and matches the condition described later. The terminal is selected and output, and the presence or absence of the input signal of the terminal is stored in the storage device (8). Also, S
The input signal terminal newly selected by W1 (4) and the presence or absence of an input signal at the terminal are stored in the storage device (8).

Next, the specific operation of the microcomputer (6) will be described with reference to FIGS.

FIG. 2 shows a flowchart of a main routine executed by the microcomputer (6). First, when the power is turned on, the fact that there is no input signal at any input terminal is stored in the storage device (8) as an initial setting, and then a signal detection loop is entered. In this loop, the input terminal to be detected is SW
2 (5) is sequentially switched to (3), (2), and (1), and the presence or absence of an input signal is detected each time. When the detection of three terminals is completed, the input terminals to be detected again are switched to (3), (2), and (1) by SW2 (5) to perform detection. Can be detected.

FIG. 3 shows a flowchart of a signal detection subroutine performed each time the SW2 (5) is switched, that is, the input signal terminal to be detected is switched. First, in step [a], the presence or absence of an input signal to the input terminal selected by SW2 (5) is determined. If there is no input signal, the input signal to this terminal is stored in the storage device (8) in step [b]. Is stored as none. And step [c]
It is determined whether or not this terminal is the terminal selected by SW1 (4). If the terminal is not the terminal selected by SW1 (4), the subroutine is terminated and the process returns to the main loop. ), Information indicating that there is no input signal in the terminal selected by SW1 (4) is stored in the storage device (8) in step [d], and the subroutine is terminated to return to the main loop. Return.

If there is an input signal at the terminal selected by SW2 (5) in step [a], information on the presence or absence of an input signal to this terminal is called from the storage device (8) in step [e]. , The presence or absence of an input, and if it is determined that there is no input signal to this terminal, step [g]
To select this terminal by SW1 (4),
In step [h], information that the terminal selected by SW1 (4) is this terminal is stored in the storage device (8), and in step [i], the storage device (8) stores that there is an input signal of this terminal. Then, in step [j], information that an input signal is present at the terminal selected by SW1 (4) is stored in the storage device (8), and the subroutine ends and returns to the main loop.

If it is determined in step [e] that there is an input, it is determined in step [f] whether or not there is an input signal to the terminal selected by SW1 (4). If there is no input signal, as described above, The storage device (8) stores information that the terminal detected in step [g] is selected as an output signal by SW1 (4) and that the terminal selected in step [h] is SW1 (4). Is stored in the storage device (8) at step [i], and the SW signal is stored at step [j].
Information that there is an input signal at the terminal selected by 1 (4) is stored in the storage device (8), and the subroutine ends and returns to the main loop. If it is determined in step [f] that there is an input signal to the path selected by SW1 (4), the subroutine is terminated and the process returns to the main loop.

Three specific operation examples of the input switching device will be described.

As a first example, an operation example in which a signal is newly input to the input terminal (2) while power is turned on and a signal is input only to the input terminal (1) will be described. Show. Before a new signal is input to the input terminal (2),
In the storage device (8), the input terminal (1) has an input signal,
The input terminals (2) and (3) store information indicating that there is no input signal, the terminal selected as an output by SW1 is (1), and there is an input signal to this terminal. Therefore, when a signal is newly input to the input terminal (2) and the signal detection means detects the input signal of the terminal (2), it is first determined that there is an input signal in step [a] of the flowchart in FIG. Therefore, the process proceeds to step [e].

In step [e], since it is determined that there is no input signal from the storage device (8) to this terminal (2), the process proceeds to step [g]. In the step [g], the terminal to be selected as the output is switched from the terminal (1) to the terminal (2) by SW1, and in the next step [h], the information that the terminal to be selected as the output is set to (2) is stored in the storage device (8). ) Is stored. In step [i], the terminal (2) performing detection
Is stored in the storage device (8), and the information that there is an input signal is stored in the terminal selected as the output in step [j]. For example, when the input terminal (1) is an input terminal for a television signal and the input terminal (2) is an input terminal for connecting to a game device, and the game device is connected and the power is turned on while watching the television, the above operation is performed. An input signal from the game device is automatically output.

As a second example, power is turned on, a signal is input to input terminals (1) and (2), and a signal input to input terminal (2) is output. In the state, an operation example in the case where the input of the signal is stopped by turning off the power of the signal source connected to the input terminal (2) is shown.

In the initial state, the storage device (8) has an input signal at the input terminals (1) and (2), the input terminal (3) has no input signal, and a terminal selected as an output by SW1. (2) stores information indicating that an input signal is present at a terminal selected as an output. If no signal is input to the terminal (2) and the signal detection means selects the input signal of (2), it is first determined that there is no input signal in step [a] of the flowchart in FIG. Proceed to [b]. This step [b]
Then, information indicating that there is no input signal at the detected terminal (2) is stored in the storage device (8), and the process proceeds to step [c].

In step [c], it is determined whether the detected terminal (2) is a terminal selected as an output by SW1. In the storage device (8), since the terminal selected as the output by SW1 is stored as (2), the process proceeds to step [d]. In step [d], information that there is no input signal is stored in the storage device (8) at the terminal selected as the output by SW1, and the subroutine of FIG. 3 is completed, and the process returns to the main loop shown in FIG.

According to FIG. 2, after detecting the input terminal (2), the SW2 is controlled so as to detect the input terminal (1), and the subroutine shown in the flowchart of FIG. 3 is performed for the terminal (1). Here, first, step [a]
Then, it is determined that there is an input signal at the detected terminal (1), and the process proceeds to step [e]. The last time this terminal is detected in step [e], it is determined that there is an input signal, so the process proceeds to step [f]. In step [f], since it is determined that there is no input signal at the terminal selected as the output by SW1 from the above, the process proceeds to step [g].

In step [g], the information that the terminal to be selected as the output is switched from the terminal (2) to the terminal (1) by SW1 is stored in the next step [h], and the information that the terminal to be selected as the output is changed to (1) is stored. It is stored in the device (8). In step [i], information that an input signal is present at the terminal (1) being detected is stored in the storage device (8), and in step [j], information that an input signal is present in the terminal selected as an output is stored in the storage device (8). You.

For example, when the game machine is used while the input signal of the television is being inputted to the input terminal (1) and the input signal of the game machine is being inputted to the input terminal (2), the game machine is turned off. The input signal of the television is automatically output by the above operation.

As a third example, an operation example in which the power is turned on while signals are being input to all the input terminals (1), (2) and (3) before the power is turned on. Show.
When the power is turned on, information indicating that there is no input signal is stored in the storage device (8) in the input terminals (1), (2), and (3) as an initial setting as shown in FIG.
The terminal (3) is detected according to the flowchart shown in FIG.

For the terminal (3), first, step [a]
, It is determined that there is an input signal, and the process proceeds to step [e]. In step [e], it is stored in the storage device that there is no input signal at the terminal (3), so the process proceeds to step [g]. In step [g], the information that the terminal to be selected as the output is set to the terminal (3) by SW1 and in the next step [h], the terminal to be selected as the output is set to (3) is stored in the storage device (8). In step [i], information that there is an input signal at the terminal (3) that is performing detection is stored in the storage device (8), and in step [j], information that there is an input signal at the terminal selected as the output is stored in the storage device (8). You.

Next, the terminal (2) is detected by switching SW2. Regarding the terminal (2), first, it is determined in step [a] that there is an input signal, so the process proceeds to step [e].
In step [e], the storage device (8) stores that there is no input signal at the terminal (2), so the process proceeds to step [g].
In the step [g], the information that the terminal to be selected as the output is switched from the terminal (3) to the terminal (2) by SW1 and the terminal to be selected as the output in the next step [h] is (2) is stored in the storage device (8). ) Is stored. In step [i], information that there is an input signal at the terminal (2) that is performing detection is stored in the storage device (8), and in step [j], information that there is an input signal at the terminal selected as the output is stored in the storage device (8). You.

Then, SW2 is switched to detect the terminal (1). For the terminal (1), first, step [a]
, It is determined that there is an input signal, and the process proceeds to step [e]. In step [e], the storage device (8) stores that there is no input signal at the terminal (1), so the process proceeds to step [g]. After step [g], the terminal to be selected as an output is switched from terminal (2) to terminal (1) by SW1 as in the case of terminal (2) described above, and the next step [h]
Then, information that the terminal to be selected as the output is set to (1) is stored in the storage device (8). In step [i], information that there is an input signal at the terminal (1) that is performing detection is
In step [j], information that there is an input signal at the terminal selected as the output is stored in the storage device (8).

Thereafter, the terminal (3) is detected again. In this case, since it is determined in step [a] of FIG. 3 that an input signal is present, the process proceeds to step [e]. Since it is determined in step [e] that the storage device (8) has an input signal at the terminal (3), the process proceeds to step [f]. In step [f], S
Since it is determined by W1 that there is an input signal at the terminal selected as the output, the detection here is terminated. Even if the terminals to be detected are subsequently switched, the terminal selected as an output by such an operation remains the terminal (1).

As described above, when the power is turned on by inputting a signal to a plurality of terminals before the power is turned on, the terminal to be output is selected in the order of the terminals (1), (2), and (3). . Needless to say, the order of the terminals to be detected in FIG. 2 may be changed in order to change the priority.

[0030]

According to the input switching device of the present invention, a path to which an input signal has recently been newly supplied is always automatically selected. For example, a game device is connected and turned on while watching a television. In such a case, the input switching is automatically performed, so that it is not necessary to manually switch the input.

When the input signal is no longer supplied to the selected path, another path to which the input signal is supplied is automatically selected. For example, a game machine is connected and the game is terminated. When the power of the device is turned off, the input is automatically switched, so that it is not necessary to manually perform the input switching.

[Brief description of the drawings]

FIG. 1 is a block diagram of an input signal switching device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of controlling input switching in the input signal switching device.

FIG. 3 is a flowchart showing an operation of controlling input switching in the input signal switching device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Signal input connection terminal 1 2 Signal input connection terminal 2 3 Signal input connection terminal 3 4, 5 SW 6 Microcomputer 7 Input signal detection means 8 Storage device

Claims (2)

[Claims] 1. An input switching device having a plurality of input terminals, wherein an input signal of each terminal is detected, and an input terminal in which a new input signal is detected is always automatically selected and output. An input switching device for automatically selecting, as an output, another terminal to which a signal is input when a signal is no longer input to the input terminal. A means for selecting an input signal terminal to be an output signal; an input signal detection means for detecting the presence or absence of an input signal; and an input input to the input signal detection means from a plurality of input signal terminals. A storage device for storing a terminal selected by a signal terminal, a terminal selected by the input signal terminal to be an output signal, presence / absence of an input signal at the terminal, and presence / absence of an input signal at each input signal terminal. 2. The control device according to claim 1, further comprising: means for selecting an input signal terminal to be used as the output signal; means for selecting an input signal supplied to the input signal detecting means; and a control device for controlling the contents stored in the storage device. An input switching device as described.