JP2004227064A - Electronic device and method for controlling power supply of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent waste of power in an electronic device and to save power. <P>SOLUTION: When bus power is received from a personal computer 3 at the time of stand-by in an audio device 1, a USB microcomputer 11 is started. When data showing that a Net MD program is started in the personal computer 3 or Net MD data are received from the personal computer 3, start instruction data are transmitted to an MD unit 14 from the USB microcomputer 11. Thus, the MD unit 14 is started. When bus power is not received from the personal computer 3 after the MD unit 14 is started, power interruption instruction data are transmitted to the MD unit 14 from the USB microcomputer 11. An operation of the MD unit 14 is stopped and the operation of the USB microcomputer is stopped. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electronic device such as an audio device and a power supply control method thereof.
[0002]
[Prior art]
USB (Universal Serial Bus) is known as a standard of an interface for connecting a control device such as a personal computer (hereinafter, referred to as a “personal computer”) and an electronic device such as a printer and a modem. This USB is supported by an OS (Operating System) generally installed in a personal computer, and uses a hot plug-in that can connect an electronic device while the personal computer is turned on, or uses an electronic device. Plug and play, etc., which can automatically execute the settings for this purpose.
[0003]
2. Description of the Related Art Conventional electronic devices are connected to a control device via a USB cable, and are turned off (hereinafter referred to as a “standby state”) when an instruction to execute some processing is input from the control device. )), The instructed processing was executed after the power of the entire electronic device was turned on. As such an electronic device, for example, the power of a VBus (power supply line) incorporated in a USB cable (hereinafter, referred to as “bus power”) in a standby state in a state where the device is connected to a control device via USB. A peripheral device that turns on the power when it is detected is known (for example, see Patent Document 1). The present invention reduces power consumption by not turning on the power when there is no possibility that data will be sent from the control device.
[0004]
[Patent Document 1]
JP-A-2002-108518
[Problems to be solved by the invention]
However, in the above-described conventional electronic device, when bus power is input from the control device in the standby state, the power of the entire device is switched on regardless of which component is used. In other words, power is also supplied to unnecessary components, and power is wasted. For example, when a control device such as a personal computer and an electronic device such as an audio device are connected with a USB cable, the following problems occur. When a personal computer instructs the audio device to record music data on an MD (Mini Disc), the audio device was turned on and the music data was recorded on the MD after turning on the power of the entire device. Power is also supplied to unnecessary components such as a CD (Compact Disc) unit and a tuner unit, and wasteful power is consumed.
[0006]
Therefore, an object of the present invention is to realize power dissipation by preventing waste of power in an electronic device.
[0007]
[Means for Solving the Problems]
The invention according to claim 1 is
In an electronic device having a plurality of components, the electronic device is connected to an external control device and an external power supply via an interface so as to be freely connected to and separated from the external power source,
In a state where the power of the electronic device is OFF, when data is input from the control device, an interface control unit that transmits start instruction data for instructing a component that processes the data to start,
The component receiving the activation instruction data from the interface control means receives the power supplied from the external power supply and activates.
[0008]
The invention according to claim 2 is the invention according to claim 1,
The interface control means is activated by power supplied from the control device when the power of the electronic device is OFF.
[0009]
The invention according to claim 3 is the invention according to claim 2,
The interface control means, when the power supplied from the control device is stopped, a power cutoff instruction for instructing the component transmitting the start instruction data to cut off the power supplied from the external power supply. Send data,
The component receiving the cutoff instruction data from the interface control means cuts off power supplied from the external power supply and stops operation.
[0010]
The invention according to claim 4 is the invention according to any one of claims 1 to 3,
An interface connected to the control device is a USB interface, and the plurality of components include an MD unit;
The interface control unit controls the electronic device when the music device receives music data from the control device while the power of the electronic device is OFF, or controls the data indicating that a program related to the MD unit is started in the control device. When receiving from the device, the start instruction data is transmitted to the MD unit.
[0011]
The invention according to claim 5 is
In a power supply control method for an electronic device having a plurality of components, the method is connected to an external control device and an external power supply via an interface so as to be freely contactable and detachable,
In a state where the power of the electronic device is OFF, when data is input from the control device, a step of transmitting start instruction data for instructing a component that processes the data to start, and
A step of receiving power supplied from the external power supply by a component that has received the activation instruction data from the interface control means, and activating the component;
It is characterized by including.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of an audio system 100 to which the present invention is applied will be described in detail with reference to the drawings.
[0013]
First, the configuration will be described.
FIG. 1 shows a functional configuration of an audio system 100 to which the present invention is applied. As shown in FIG. 1, the audio system 100 includes an audio device 1, an AC adapter 2, and a personal computer 3. The audio device 1 and the AC adapter 2 are connected by a power cable E, and the audio device 1 and the personal computer 3 are connected by a USB cable C.
[0014]
The audio device 1 is an electronic device provided with a USB interface, and records music data on the MD and records the music data on the MD according to a control signal received from the personal computer 3 via a USB cable or an input instruction from an operation unit of the audio device 1. And reproduces and outputs music data recorded on the CD.
[0015]
The AC adapter 2 is an external power supply that is connected to the audio device 1 via a power cable E and supplies power to the audio device 1.
[0016]
The personal computer 3 is a control device connected to the audio device 1 via the USB cable C, and transmits various control signals to the audio device 1 to execute a sound reproduction output process and the like. For example, the personal computer 3 stores a program for Net MD (registered trademark), which is an interface standard for connecting to the audio device 1 via USB, and when this program is started, the Net MD program is started in the audio device 1 Then, data (AVC command) indicating that the operation has been performed is transmitted. Also, after activating the Net MD program, the personal computer 3 downloads music data and the like from a music distribution service site on the Internet in accordance with a user's input instruction. In addition, the downloaded music data and the like are transmitted to the audio device 1 via the USB cable C, and are checked out (recorded) or reproduced on a recording medium such as an MD.
[0017]
The USB cable C is composed of two communication lines (D +, D-) for signal transmission and four lines of VBus (power supply line) and GND (ground) for power supply according to the USB standard. The USB cable C connects the audio device 1 and the personal computer 3, and transmits and receives data between these devices.
The data indicating the activation of the Net MD program and the music data to be recorded on the MD are transmitted from the personal computer 3 to the audio device 1 via the two communication lines.
[0018]
Hereinafter, each component of the audio device 1 will be described.
As shown in FIG. 1, the audio device 1 includes a USB microcomputer 11, a power control unit 12, an MD unit 14, a USB audio 15, a selector 16, an amplifier 17, a speaker 18, an internal bus 19, an operation unit 20, an audio microcomputer 21, It comprises a display unit 22, a processing control unit 23, a multi-decode DSP (Digital Signal Processor) 24, a RAM (Random Access Memory) 25, a ROM (Read Only Memory) 26, and a CD unit 27.
[0019]
The USB microcomputer 11 includes, for example, a one-chip microcomputer, and includes an arithmetic unit, a storage device, and a Net MD security circuit (not shown), and operates on bus power supplied from the personal computer 3 via a USB cable. Here, the Net MD security circuit performs security management when the Net MD is connected to the personal computer 3, and decrypts encrypted music data received from the personal computer 3 during checkout (recording).
The USB microcomputer 11 executes various processes described below in cooperation with various processing programs stored in a built-in storage device. The various processing programs include a standby power control processing program for implementing the standby power control processing.
[0020]
Further, the USB microcomputer 11 branches and collects communication data according to the USB standard, and the components connected to the MD unit 14, the USB audio 15, the internal bus 19 (the processing control unit 23 to the CD unit 27), Various data are transmitted and received between each unit of the audio microcomputer 21 and the personal computer 3. For example, a USB audio signal and control data (operation command information) received from the personal computer 3 are transmitted to each component of the audio device 1, and control data (instruction information and the like) supplied from the audio microcomputer 21 are transmitted to the personal computer 3. I do.
The operation of the USB microcomputer 11 may be stopped when the supply of the bus power to the USB microcomputer 11 is stopped. In this case, the power to the MD microcomputer 14 is linked to the stop of the USB microcomputer 11. It is also possible to adopt a configuration of blocking.
[0021]
The power control unit 12 starts inputting the power supplied from the AC adapter 2 to the MD microcomputer 14 when receiving data requesting power supply from the MD microcomputer 14 while the audio device 1 is in the standby state. I do. On the other hand, when receiving data that instructs to stop power supply from the USB microcomputer 11 (hereinafter, referred to as “power cutoff instruction data”), the power supply to the MD microcomputer 14 is stopped.
In addition, when the power ON of the audio device 1 is instructed by an input from the operation unit 20, the power control unit 12 receives the power ON instruction from the audio microcomputer 21 and sends the power ON instruction to each component of the audio device 1. On the other hand, power supply or power supply is stopped.
[0022]
The MD unit 14 is, for example, a component compliant with the Net MD standard, and includes an MD unit microcomputer and an MD control module (not shown).
The MD unit microcomputer is activated by the bus power when bus power is input from the personal computer 3 while the power of the audio device 1 is off. When data for instructing activation of the entire MD unit 14 (hereinafter, referred to as “activation instruction data”) is input from the USB microcomputer 11, data for requesting power supply is transmitted to the power control unit 12. Then, power is supplied from the power control unit 12 and the entire MD unit 14 starts.
The MD control module receives music data (for example, PCM data) and the like received from the personal computer 3, decodes the music data, and records the data on the MD. At this time, the MD control module transmits a content hash (specific information uniquely obtained from the music data) for copyright protection to the personal computer 3. Further, the MD control module reproduces the MD on which the music data is recorded, and sequentially supplies the audio signal A1 obtained by decoding to the amplifier 17 and the like via the selector 16.
[0023]
The USB audio 15 includes, for example, a CODEC (coder / decoder) IC having a communication function in accordance with the USB standard, and a USB audio signal (isochronous transfer frame or the like) supplied from the personal computer 3 via the USB microcomputer 11. ) Are sequentially obtained. Then, the audio signal A2 obtained by decoding the obtained USB audio signal is sequentially supplied to the amplifier 17 and the like via the selector 16.
[0024]
The selector 16 includes, for example, a three-input one-output selector circuit and the like, receives the audio signals A1 to A3 supplied from the MD unit 14, the USB audio 15, and the multi-decode DSP 24, respectively, and is supplied from the audio microcomputer 21. One of the audio signals is selected according to a switching signal or the like. The selector 16 outputs the selected audio signal to the speaker 18 and the like via the amplifier 17.
[0025]
The amplifier 17 includes an amplifier circuit and the like, amplifies the audio signal selected and output by the selector 16 as appropriate, and supplies the amplified audio signal to the speaker 18.
[0026]
The speaker 18 receives the audio signal amplified by the amplifier 17 and emits a predetermined music or the like according to the input audio signal.
[0027]
The internal bus 19 is a bus that connects the processing control unit 23, the multi-decode DSP 24, the RAM 25, the ROM 26, and the CD unit 27 through a common path. Mainly, necessary information (signal) is transmitted between the processing control unit 23 and the multi-decode DSP 24 to the drive controller 27.
[0028]
The operation unit 20 includes, for example, a plurality of key switches arranged on the front surface of the audio device 1 and supplies instruction information to the audio microcomputer 21 according to a user operation (such as pressing).
[0029]
The audio microcomputer 21 is formed of, for example, a one-chip microcomputer, and includes an arithmetic unit and a storage device (not shown). The audio microcomputer 21 incorporates various programs for controlling the audio device 1 in its storage device, and controls each unit of the audio device 1 in cooperation with the various programs and the arithmetic device.
[0030]
The audio microcomputer 21 controls the USB microcomputer 11, the MD unit 14, the selector 16, the processing control unit 23, and the like. Specifically, according to the instruction information supplied from the operation unit 20 and the control data sent from the personal computer 3 via the USB microcomputer 11, the processing control unit 23 is controlled, and the CD unit 27 reproduces a CD. I do. At this time, macro commands (for example, PLAY, STOP, etc.) are transmitted and received between the audio microcomputer 21 and the processing control unit 23 by UART (Universal Asynchronous Receiver Transmitter) communication. In addition, the audio microcomputer 21 controls the MD microcomputer 14 in accordance with the instruction information and the control data, and reproduces or records MD music data. At this time, macro commands are also transmitted and received between the MD microcomputers 14 through UART communication. Further, the audio microcomputer 21 receives or shuts off the power supplied from the power supply control unit 12 to each component of the audio device 1 when the power ON / OFF instruction is input from the operation unit 20. Instruct that However, when the power ON instruction is not input from the operation unit 20 when the audio device 1 is in the standby state, the ON / OFF control of the power of each component is under the control of the USB microcomputer 11.
[0031]
The display unit 22 includes a liquid crystal display panel or the like, and displays information indicating an operation state of the audio apparatus 1 and a connection state with the personal computer 3 according to display data supplied from the audio microcomputer 21.
[0032]
The processing control unit 23 includes a CPU (Central Processing Unit) and controls the multi-decode DSP 24 and the CD unit 27 according to a program stored in the ROM 26 (a program loaded into the RAM 25).
For example, the processing control unit 23 controls the CD unit 27 to read out music data of a predetermined music format from the CD loaded in the audio device 1 and transfer the read music data to the multi-decode DSP 24, thereby To play.
[0033]
The multi-decode DSP 24 corresponds to a plurality of music formats (encoding method and compression method) such as, for example, CD-DA (CD Digital Audio), MP3 (MPEG1 Audio Layer-3) and WMA (Windows (R) Media Audio). , And decodes the music data read from the CD as appropriate to generate an audio signal A3. Further, the multi-decode DSP 24 supplies the generated audio signal A3 to the selector 16.
[0034]
The RAM 25 is composed of, for example, an SDRAM (Synchronous Dynamic RAM) that operates in synchronization with a bus clock, and loads a program stored in the ROM 26. Further, the RAM 25 stores work data and the like necessary when the control processing unit 23 executes the program.
[0035]
The ROM 26 is, for example, a flash ROM that is a rewritable read-only memory, and stores a program executed by the processing control unit 23 and the like.
[0036]
The CD unit 27 includes a CD drive controller and a CD drive unit (not shown).
The CD drive controller includes, for example, an ATAPI (AT Attachment Packet Interface) standard controller, and controls the CD drive unit. That is, the CD drive controller reads music data from the CD loaded in the CD drive unit, and supplies the read music data to the multi-decode DSP 24.
The CD drive unit includes, for example, an ATAPI standard CD drive device, and is controlled by a CD drive controller to reproduce a loaded CD or the like.
The CD drive unit can reproduce not only a commercially available music CD, but also a CD-R (CD Recordable), a CD-RW (CD ReWritable), and the like. Then, music data in a music format such as MP3 or WMA recorded on a CD-R or the like is read and supplied to the multi-decode DSP 24 via a drive controller or the like.
[0037]
Next, the operation will be described.
A program for implementing each function described in the flowchart of FIG. 2 is stored in the USB microcomputer 11 in the form of a readable program code, and the USB microcomputer 11 complies with the program code. Execute the operation sequentially. Note that by providing an interface for connecting to the external device in the audio device 1, an operation specific to the audio device 1 may be executed using a program or data supplied from the external device.
[0038]
In the standby power control process shown in FIG. 2, first, it is determined whether or not the audio device 1 is in a standby state (step S1). If the audio device 1 is in a standby state (step S1; YES), the process proceeds to step S2. If it is not in the standby state, that is, if the power is on (step S1; NO), this processing ends.
[0039]
Next, it is determined whether or not the bus power is received from the personal computer 3 (step S2). If the bus power is received (step S2; YES), the process proceeds to step S3, and the bus power is received. If not (step S2; NO), this process ends. Next, the USB microcomputer 11 is activated by the bus power, and it is recognized that the USB connection has been established (step S3).
[0040]
Subsequently, it is determined whether data indicating that the Net MD program has been started in the personal computer 3 or Net MD data has been received from the personal computer 3 (step S4). If the data has been received (step S4; YES), the activation instruction data is transmitted to the MD unit 14, the MD unit 14 is activated (step S5), and the process proceeds to step S6. On the other hand, if neither the data indicating the activation of the Net MD program nor the Net MD data is received (step S4; NO), the process proceeds to step S6.
[0041]
Next, it is determined whether or not the bus power is received from the personal computer 3 (step S6). If the bus power is not received (step S6; NO), the process returns to step S4. On the other hand, when the bus power is received from the personal computer 3 (step S6; YES), the power cutoff instruction data is transmitted to the MD unit 14, and the operation of the MD unit 14 is stopped (step S7). Next, the power of the USB microcomputer 11 is turned off (step S8), and the standby power control process ends.
[0042]
As described above, in the audio device 1, when the bus power is received from the personal computer 3 during standby, the USB microcomputer 11 is activated. Thereafter, when data indicating that the Net MD program has been started in the personal computer 3 or when the Net MD data is received from the personal computer 3, the start instruction data is transmitted from the USB microcomputer 11 to the MD unit 14. The MD unit 14 is activated. When the bus power is no longer received from the personal computer 3 after the MD unit 14 is started in this way, the power-off instruction data is transmitted from the USB microcomputer 11 to the MD unit 14, and the operation of the MD unit 14 is stopped. Further, the operation of the USB microcomputer stops.
[0043]
Therefore, according to the above embodiment, when only the MD unit 14 needs to be operated in the audio device 1, power is supplied only from the external power supply to the MD unit 14. Power is not supplied, power consumption can be reduced. In particular, when the personal computer 3 connected via the USB cable C is a model that transmits bus power to the audio device 1 even during standby, significant power savings can be realized.
[0044]
In the above embodiment, the case where the MD unit of the audio device 1 is used has been described as an example. However, the components that can be controlled by the USB microcomputer 11 are not limited to this.
[0045]
Further, the present invention is not limited to the above embodiment. For example, in each of the above embodiments, the audio device is described as an example of the electronic device according to the present invention, but the type of the electronic device is not limited to this. The electronic device according to the present invention may be any device provided with a USB standard interface. For example, peripheral devices such as a printer and a modem connected to a control device such as a personal computer can be applied.
[0046]
In addition, the detailed configuration and detailed operation of the audio system 100 to which the present invention is applied can be appropriately changed without departing from the gist of the present invention.
[0047]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, power consumption can be implement | achieved by preventing waste of electric power in an electronic device.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an example of a configuration of an audio system according to an embodiment of the present invention.
FIG. 2 is a flowchart illustrating standby power control processing according to the embodiment of the present invention.
[Explanation of symbols]
Reference Signs List 1 audio device 2 AC adapter 3 personal computer 11 USB microcomputer 12 power control unit 14 MD unit 15 USB audio 16 selector 17 amplifier 18 speaker 19 internal bus 20 operation unit 21 audio microcomputer 22 display unit 23 processing control unit 24 multi-decode DSP
25 RAM
26 ROM
27 CD unit 100 Audio system C USB cable E Power cable

Claims (5)

In an electronic device having a plurality of components, the electronic device is connected to an external control device and an external power supply via an interface so as to be freely contactable and detachable,
In a state where the power of the electronic device is OFF, when data is input from the control device, an interface control unit that transmits start instruction data for instructing a component that processes the data to start,
An electronic device, wherein the component unit that receives the start instruction data from the interface control unit receives and starts power supplied from the external power supply. 2. The electronic device according to claim 1, wherein the interface control unit is activated by power supplied from the control device when the power of the electronic device is OFF. The interface control means, when the power supplied from the control device is stopped, a power cutoff instruction for instructing the component transmitting the start instruction data to cut off the power supplied from the external power supply. Send data,
The electronic device according to claim 2, wherein the component unit that receives the cutoff instruction data from the interface control unit cuts off power supplied from the external power supply and stops operation. The interface connected to the control device is a USB interface, and the plurality of components include an MD unit;
The interface control unit controls the electronic device when the music data is received from the control device while the power of the electronic device is turned off, or when the control device controls the data indicating that the program related to the MD unit is started. The electronic device according to any one of claims 1 to 3, wherein the activation instruction data is transmitted to the MD unit when the activation instruction data is received from the device. In a power supply control method for an electronic device having a plurality of components, the method is connected to an external control device and an external power source via an interface so as to be freely connected to and separated from the external power source.
In a state where the power of the electronic device is OFF, when data is input from the control device, a step of transmitting start instruction data for instructing a component that processes the data to start, and
A step of receiving power supplied from the external power supply by a component that has received the activation instruction data from the interface control means, and activating the component;
A power supply control method comprising:

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