JP2000132494A - Computer system and audio output control method of the system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent audio devices from generating audio outputs at the same time on a PC having a USB interface. SOLUTION: When the connection of a USB speaker 13 or USB headphones 14 is detected, control inhibiting the output of a non-USB speaker 12 is performed. When the USB speaker 13 and USB headphones 14 are both connected, control for allowing audio output from one of those USB audio devices is performed. Through priority control between the USB audio devices and non-USB audio device, audio devices are prevented from generating audio outputs at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a computer system such as a personal computer having a USB interface and an audio output control method in the system.

[0002]

2. Description of the Related Art Conventionally, in a desktop or notebook type personal computer (hereinafter, referred to as a PC), audio data is output through a speaker or the like using an audio device such as a sound card or an audio controller. I have. The output destination is a built-in speaker, an external speaker, an external headphone, or the like. When external headphones are connected, sound from the built-in or external speakers is automatically cut off by the function of the sound card or the audio controller.

In recent PCs, USB (Un
There are an increasing number of devices equipped with an versatile Serial Bus interface as standard equipment. In this case, US
By connecting the B audio device to the USB port of the PC, audio output from the USB audio device can be performed.

[0004]

However, conventionally, since a sound card (or audio controller), which is a non-USB device, and a USB interface are managed independently of each other, a USB audio device is connected to the USB interface. Then, audio output is performed from both the built-in or external speaker connected to the sound card and the USB audio device. In particular, when a USB headphone is connected as a USB audio device, the sound of the built-in or external speaker is not automatically cut off. There is a problem that it is lost.

[0005] In addition, the USB interface has a US interface.
Since a plurality of USB devices can be connected by the function of the B hub function, a plurality of USB audio devices may be connected to a USB interface in some cases. In this case, since all USB audio devices operate effectively, sound is output from these USB audio devices together.

[0006] The present invention has been made in view of such a point, and by performing priority control between a USB audio device and a non-USB audio device and priority control between USB audio devices, it is possible to simultaneously perform the control. An object of the present invention is to provide a computer system and an audio output control method capable of preventing audio output from a plurality of audio devices and realizing an optimal environment for using a USB audio device.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a computer system having a USB interface, comprising: means for detecting that a USB audio device is connected to the USB interface; When connection of a device is detected, a US
Means for prohibiting audio output from audio devices other than the B audio device.

In this computer system, U
The SB audio device has a higher priority than the non-USB audio device, and when a USB audio device is connected, audio output from the non-USB audio device is automatically prohibited. Therefore, even in a PC or the like equipped with a sound card and having a USB interface, it is possible to prevent a problem that sounds are output from a plurality of audio devices at the same time.

Also, a USB interface is
Means for detecting whether or not another USB audio device is already connected to the USB interface when the B audio device is connected; and detecting when another USB audio device is already connected to the USB interface. US
Based on a predetermined priority order for the type of B audio device, the highest priority is set so that audio is output only from the highest priority USB audio device among the plurality of connected USB audio devices. And a unit for prohibiting audio output from other USB audio devices other than the USB audio device having a high USB audio device. Such priority control between USB audio devices is performed between USB audio devices and non-USB devices.
By using in combination with the priority control with the audio device, it is possible to always output the sound only from a single audio device.

As the priority control between the USB audio devices, control according to the type of the USB audio device as well as control according to the connection order can be performed as described above. Also,
Utilizing the plug-and-play function of the USB interface, when a USB audio device is connected, a screen for allowing the user to select an audio device to be used is displayed, and the audio device to be used according to a user operation on the screen is displayed. You can also choose.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a basic configuration of a computer system according to an embodiment of the present invention. This computer system is a desktop or notebook type personal computer (PC). As shown, a CPU 1, a host / PCI bridge 2, a main memory 3, an IDE interface 4, an HDD 5, and a VGA controller 6, as well as a USB interface 1
0, and sound card (audio controller)
11 are provided.

The sound card 11 is a non-USB audio device for controlling a built-in or external speaker 12 and outputting audio from the speaker 12, and is equipped with a sound source and a CODEC function. Specifically, the output destination of the audio data from the sound card 11 includes a built-in speaker, an external speaker, an external headphone, and the like. Here, the speaker 12 is illustrated as a representative of these. Sound card 1
1 has a function of automatically switching the output destination of audio data. When either an external speaker or an external headphone is connected, the output from the built-in speaker is stopped. When an external headphone is connected, the output from the external speaker is stopped, not only the built-in speaker.

The USB interface 10 operates as a USB host controller, and has a function of automatically detecting connection / disconnection of a USB device in order to realize plug and play. That is, USB
The interface 10 allows a device connected via the interface to be dynamically connected / disconnected by a plug-and-play function, thereby enabling dynamic device management.
The system allows the connection of new devices without resetting in hardware and software.

The USB interface 10 has a built-in root hub (HUB) mechanism.
Two USB ports for connecting USB devices are derived from the interface 10. In the example of FIG. 1, a USB keyboard 16 is connected to one USB port, and a USB hub (HUH) is connected to the other USB port.
B) 17 is connected.

The USB hub (HUB) 17 has three US
A B port is provided, and a USB speaker 13, a USB headphone 14, a USB mouse 15, and the like can be connected as shown. The USB speaker 13 and the USB headphone 14 have the same audio function (sound source function and CODEC) as the sound card 11.
Function) is provided.

In the conventional system, audio data on the PC is output from the speaker 12. If US
US such as B speaker 13 or USB headphone 14
If the B audio device is connected while the speaker 12 is left as it is, there is a problem that sound is generated from both the USB audio device and the non-USB speaker 12.

Therefore, in the present embodiment, even if a USB speaker 13 and a USB headphone 14 are newly added, a single device to which audio data is output is provided.
Is detected, the control for prohibiting the output from the non-USB speaker 12 is performed. When both the USB speaker 13 and the USB headphone 14 are connected, control for performing audio output from only one of the USB audio devices is performed. Such priority control between the USB audio device and the non-USB audio device and priority control between the USB audio devices are realized by software.

FIG. 2 shows the correspondence between hardware and software of the system according to this embodiment. As shown, the PCI bus driver is a host / PC
This is a driver for controlling the operation on the PCI bus such as the I-bridge 2, and a USB host driver for controlling the USB interface 10 exists below the driver. An audio class driver for controlling an audio device is provided in a class driver composed of a plurality of driver groups, and a sound card corresponding to each of the sound card 11, the USB speaker 13, and the USB headphone 14 is provided through the audio class driver. Card driver, USB speaker driver, U
Communication with the SB headphone driver is performed.

USB audio equipment (USB speaker 1
3. The priority control between the USB headphone 14) and the non-USB audio device (sound card 11) can be realized by assigning a priority to the level of the PCI interface, for example, by controlling a PCI bus driver or an OS. This is shown in FIG.

FIG. 3 shows a functional configuration for priority control at the level of the PCI interface.
When the SB audio detection unit 101 detects the connection of the USB audio device, the bridge control unit 102 controls the host / PCI bridge 2 and the PCI bus, and the data flow to the sound card 11 is cut off.
As a result, audio output from the speaker 13 is prohibited. The sound card 11 from which the data has been cut off does not flow the data to be output, but is not completely separated from the sound card 11 but exists as a device in the system. Therefore, when the USB audio device is detached, the audio can be immediately output from the speaker 12 using the sound card 11.

The priority control between USB audio devices can be realized by setting priorities according to the type of the USB audio device, for example, by controlling an audio class driver or an OS. This is shown in FIG.

FIG. 4 shows a functional configuration for priority control between USB audio devices. The USB audio device priority control unit 201 manages the priority for each type of USB audio device. As shown, when a plurality of USB audio devices (USB audio device A, USB audio device B, USB audio device C) are connected,
Only the audio output from the device with the highest priority among the B audio device A, the USB audio device B, and the USB audio device C is permitted, and the audio output from the other audio devices unloads the corresponding driver. Or by interrupting the flow of data to the USB audio device.

Therefore, the USB headphone 14 is
If the priority is set higher than that of the SB speaker 13, the non-USB speaker 12 and the USB speaker 1 are combined with the priority control at the interface level in FIG.
3. In an environment where the USB headphone 14 exists,
Audio output can be performed only from the B headphones 14.

Instead of setting priorities for each type of USB audio device, the USB device connected last is not set.
Priority control can also be performed according to the connection order so that only audio devices are enabled.

Next, a specific procedure of audio output control in this embodiment will be described. FIG. 5 is a flowchart illustrating a procedure of priority control between a USB audio device and a non-USB audio device.

Here, the operation when the USB speaker 13 is connected while the speaker 12 is connected will be described. When the connection of the USB speaker 13 is detected (step S101), the USB speaker 13 is recognized from the system by the plug and play function (step S10).
2). Then, in step S103, the initialization process of the USB speaker 13 is started, and the device driver corresponding to the USB speaker 13 is automatically loaded (installed) and becomes usable. When the initialization process of the USB speaker 13 is completed, it is confirmed whether or not the already connected output device, in this example, the speaker 12 is present. If the USB speaker 13 does not exist, the USB speaker 13 is the only output device, so that the USB speaker 13 is initialized and terminated. When the speaker 12 is detected (Y in step S104),
The data flow to the sound controller 11 is interrupted (step S105). At this time, the fact that the flow of data to the sound controller 11 has been interrupted is stored as information in the system. By doing so, the audio data does not flow to the sound card 11, and instead, the USB speaker 12 is the only device that can receive the audio data.

Thereafter, not only the USB speaker 13 but also the US speaker
When a USB audio device is connected via the B interface 10, the previously connected audio output device (including a sound card direct connection type and a USB device)
The flow of data to the USB audio device is interrupted, and the newly connected USB audio device is given top priority. Similarly, when the USB headphone 14 of FIG. 1 is connected after the USB speaker 13, the flow of audio data to the USB speaker 13 is cut off. At this time, the fact that the flow to the USB speaker 13 has been interrupted is stored in the system as information.

In this case, the most recently connected device has the highest priority, and a single audio output can be realized. Each device whose data is interrupted only stops the data to be output from flowing, and is not completely disconnected, but exists as a device in the system. Therefore, when the connection of the USB audio device that has been given the highest priority is released, the rest of the USB audio devices can be recovered, and when the connection of all the USB audio devices is released, the speaker 12 can be recovered. . If the information of the invalidated device is stored in a form that can be referred to other devices, even if the connection is released in a different order from the connection order, the other devices can be easily restored.

The presence or absence of the speaker 12 can be detected by the device driver corresponding to the connected USB speaker. In this case, the US
The B speaker driver cuts off the flow of data to the sound controller 11 through the PCI driver or the OS or under its own control.

FIG. 6 shows USB audio equipment and non-USB
11 is a second example of the priority control with the audio device.
When the connection of the USB speaker 13 is detected (step S
201), the USB speaker 13 is recognized from the system by the plug and play function (step S20).
2). Then, in step S203, the initialization process of the USB speaker 13 is started, and the device driver corresponding to the USB speaker 13 is automatically installed and becomes usable. When the initialization process of the USB speaker 13 is completed, it is confirmed whether or not the already connected output device, in this example, the speaker 12 is present. If the USB speaker 13 does not exist, the USB speaker 13 is the only output device. When the speaker 12 is detected (Y in step S204), a pop-up menu screen for allowing the user to select a device to output audio data is displayed (step S20).
5). On this pop-up menu screen, all currently connected audio output devices are listed.
Then, the device selected on the screen is given top priority, and the flow of data to other devices is interrupted (step S20).
6).

It should be noted that the menu screen is not displayed when the USB speaker 13 is connected as described above, but the user can use the menu screen as shown in FIG. May be made to select a priority in advance. The selection result is managed in the system, and then, when an audio device is connected to the system, the priority information of the audio device is inquired to the system, and the highest priority device may be specified.

FIG. 8 shows a procedure for performing priority control between USB audio devices using the type of the USB audio device. When the connection of the USB headphone 14 is detected (step S301), first, the USB speaker 1
The presence or absence of the connection 3 is confirmed (step S302). U
When the SB speaker 13 is not connected, since the USB headphone 14 is the only USB audio device, the device driver (USB headphone driver) corresponding to the USB headphone 14 is loaded and the USB headphone 14 is loaded.
Put the headphones 14 in a usable state (step S3
04).

On the other hand, when the USB speaker 13 is connected, the priority relationship between the USB headphone 14 and the USB speaker 13 is checked, and if the USB headphone 14 has a higher priority than the USB speaker 13 (step S1). (Y in S303), the device driver (USB speaker driver) corresponding to the USB speaker 13 is unloaded, and the device driver (USB headphone driver) corresponding to the USB headphone 14 is loaded (step S305). Thereby, the USB speaker 1
3 is not output, and audio output is performed only from the USB headphone 14.

If the USB speaker 13 has a higher priority than the USB headphone 14 (step S
Until the removal of the USB speaker 13 is detected (N in 303), loading of a device driver (USB headphone driver) corresponding to the USB headphone 14 is awaited (step S306).

As described above, according to the present embodiment, (1) a priority is assigned according to the type of USB device, and when a device with a higher priority is connected, audio data is output to the device; Do not output to devices with low

(2) Priorities are assigned to audio output devices that are not connected via USB, and similar control is performed. (3) The connection order is prioritized, and the last connected audio device is treated as the highest priority, and the same control is performed.

(4) The user is allowed to set the priority and control the connection. (5) Using a USB plug and play function, a menu for setting the priority is dynamically displayed at the same time as the connection of the device, and the user is allowed to set the menu.

By executing the above control in an appropriate combination, it is possible to prevent simultaneous audio output from a plurality of audio devices, and to realize an optimal environment for using USB audio devices.

Since the control procedure of the audio output destination of the present embodiment can be performed by a computer program such as a device driver, the computer program is simply introduced into a PC having a USB interface through a storage medium. The same effect as in the embodiment can be obtained.

Further, the control of the audio output destination in the present embodiment is basically a priority control between audio devices having an audio function. The present invention is also applicable to audio equipment connected to an IEEE 1394 interface.

[0041]

As described above, according to the present invention,
By performing priority control between the USB audio device and the non-USB audio device and priority control between the USB audio devices, it is possible to prevent simultaneous audio output from a plurality of audio devices,
An optimal environment for using a USB audio device can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a computer system according to an embodiment of the present invention.

FIG. 2 is an exemplary view showing a relationship between software and hardware in the system according to the embodiment;

FIG. 3 is an exemplary view for explaining the principle of audio output destination control at the interface level in the system according to the embodiment.

FIG. 4 is an exemplary view for explaining the principle for controlling an audio output destination by priority control according to the type of USB audio device in the system of the embodiment.

FIG. 5 is an exemplary flowchart illustrating the procedure of priority control between a USB audio device and a non-USB audio device executed in the embodiment.

FIG. 6 is an exemplary flowchart illustrating a second example of the procedure of priority control between a USB audio device and a non-USB audio device which is executed in the embodiment.

FIG. 7 is an exemplary view showing an example of a menu screen for priority control used in the embodiment.

FIG. 8 is an exemplary flowchart illustrating the procedure of priority control between USB audio devices executed in the embodiment.

[Description of Signs] 1 ... CPU, 2 ... Host / PCI bridge, 10 ... US
B interface, 11 sound card, 12 speaker, 13 USB speaker, 14 USB headphone, 15 USB mouse, 16 USB keyboard,
101: USB audio detection unit, 102: Bridge control unit, 201: USB audio device priority control unit.

Claims (9)

[Claims] 1. A computer system having a USB interface, a means for detecting that a USB audio device is connected to the USB interface, and a device provided in the computer system when the connection of the USB audio device is detected. Means for prohibiting audio output from audio devices other than USB audio devices. 2. A means for detecting whether or not another USB audio device is already connected to the USB interface when a USB audio device is connected to the USB interface; and wherein another USB audio device is already connected to the USB interface. When it is detected that the USB audio device has the highest priority among the plurality of connected USB audio devices based on a predetermined priority order for the type of the USB audio device, 2. The apparatus according to claim 1, further comprising means for prohibiting audio output from another USB audio device other than the USB audio device with the highest priority so as to be output.
Computer system as described. 3. A means for detecting whether or not another USB audio device is already connected to the USB interface when a USB audio device is connected to the USB interface, and a device for detecting whether or not another USB audio device is already connected to the USB interface. Means for prohibiting audio output from an already connected USB audio device so that audio output is performed only from a newly connected USB audio device when the connection is detected. The computer system according to claim 1, wherein 4. A computer system having a USB interface, wherein: a means for detecting that a USB audio device is connected to the USB interface; and a device provided in the computer system when the connection of the USB audio device is detected. Means for detecting another audio device that is present and presenting a screen for allowing the user to select which of the detected other audio device and the connected USB audio device to use for audio output, Means for selectively selecting an audio device that performs audio output according to an operation. 5. A computer system having a USB interface, wherein when a USB audio device is connected to the USB interface, means for detecting whether or not another USB audio device is already connected to the USB interface. When it is detected that another USB audio device is connected, the plurality of connected USB audio devices are determined based on a predetermined priority order for the type of the USB audio device or the connection order of the USB audio devices.
Means for selecting a USB audio device that performs audio output from among the audio devices, and prohibiting audio output from other USB audio devices. 6. A computer system equipped with a first audio device and having an interface connectable to an external audio device having a sound source function similar to that of the first audio device, wherein the external audio device is connected to the interface. A computer system, comprising: means for detecting the connection of the external audio device; and means for prohibiting audio output from the first audio device when the connection of the external audio device is detected. 7. An audio output control method applied to a computer system having a USB interface, comprising: detecting whether a USB audio device is connected to the USB interface, and detecting the connection of the USB audio device. An audio output control method comprising: prohibiting audio output from an audio device other than a USB audio device provided in the computer system. 8. An audio output control method applied to a computer system having a USB interface, comprising: detecting whether a USB audio device is connected to the USB interface, and detecting the connection of the USB audio device. When detecting another audio device provided in the computer system, and prompting the user to select which of the detected other audio device and the connected USB audio device is to be used for audio output. The audio output control method according to claim 1, wherein an audio device for outputting audio is selectively selected according to a user operation. 9. An audio output control method applied to a computer system having a USB interface, wherein when a USB audio device is connected to the USB interface, another USB audio device is already connected to the USB interface. If it is detected that another USB audio device is already connected, based on a predetermined priority order for the type of USB audio device or the connection order of the USB audio device, Multiple connected USB
An audio output control method, wherein a USB audio device that performs audio output is selected from among audio devices, and audio output from other USB audio devices is prohibited.