JP2001290753A - Electronics - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To easily realize a plurality of available data transfer functions without burdening a host. SOLUTION: When a USB cable is connected, a CPU core 1 stores a storage device (MassStorag) when a function switch of a key block 5 is in a PLAY mode.
e Class), the device configuration of the USB port 13 is performed. On the other hand, if the function switch is REC
In the mode, the video image input device (Video Im
aging Class), the device configuration of the USB port 13 is performed. Further, when the function switch is operated in a state where the USB cable is connected, the CPU core 1 once disconnects the USB cable once and then reconnects it, and then, according to the state of the function switch, The device configuration of the USB port 13 is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device having a plurality of functions, and more particularly to an electronic device which can be connected to an electronic device as a device corresponding to the plurality of functions.

[0002]

2. Description of the Related Art In recent years, personal computers (PCs)
Is connected to electronic devices (such as printers, cameras, and scanners) having various functions. For example, a so-called digital camera that captures an image and stores it in a storage medium is a US camera.
When the digital camera is connected to a PC using the Universal Serial Bus (B), the digital camera is connected to the storage device (Mass) by the PC.
Storage Class: a device having a storage function). This has the same effect as connecting a hard disk to the PC, and has the advantage that it can be used from various applications. On the other hand, when a so-called PC camera that functions as a monitor camera of the PC and has only an imaging unit that captures an image is connected to the PC, the PC camera sends a video image input device (Video Imaging Device)
ce: device having a video image acquisition function). This is mainly used for sequentially inputting images captured by a PC camera to a PC, that is, for inputting a moving image, and is used in an application such as a TV conference.

As described above, the PC recognizes the electronic device as a device having a predetermined function by the connected electronic device. This is realized when the electronic device has device information relating to the function of its own terminal, and the PC reads and recognizes the device information when connected to the PC.

[0004]

When a conventional electronic device is connected to a PC, it transmits preset device information based on a request from the PC. Thereby, the PC can recognize the connected electronic device as a device corresponding to the device information, but has only predetermined device information even if the electronic device has a plurality of functions. Therefore, there is a problem that the PC is recognized only as a device corresponding to the device information. For example, the digital camera has a function (corresponding to a storage device) of capturing an image and storing it in a storage medium, and a function of outputting a through image to capture the image (corresponding to an image input device).
Having. Conventionally, such a digital camera has only a plurality of functions, but stores only storage device information as device information, and thus is recognized only as a storage device when connected to a PC.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an electronic device having a plurality of functions that allows a partner electronic device to easily recognize device information corresponding to the plurality of functions.

[0006]

To achieve the above object, an electronic device according to the present invention is connected to another electronic device and transmits device information based on a request from the other electronic device. In the device, storage means for storing device information corresponding to a plurality of functions, function switching means for switching a function to a predetermined function among the plurality of functions, and device information corresponding to a function switched by the function switching means A device setting means for reading and setting from the storage means, and a transmitting means for transmitting device information set by the device setting means when requested by the other electronic device.

In a preferred embodiment, in the electronic device according to the first aspect, for example, the device setting unit includes a detecting unit configured to detect a connection to the another electronic device. Device information corresponding to the function when the connection is detected by the detection means may be set.

In a preferred embodiment, the electronic device according to the first aspect includes a power supply unit for turning on the power of the electronic device, and the device setting unit includes a power supply unit. Device information corresponding to a function when the power is turned on may be set.

In a preferred aspect, in the electronic device according to the first aspect, for example, the function of the device setting unit is controlled by the function switching unit during connection with the other electronic device. When switched, the device information corresponding to the switched function may be set after temporarily disconnecting the connection with another electronic device.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. A. Configuration of Embodiment A digital camera will be described as an example of an electronic apparatus having a plurality of functions according to an embodiment of the invention. FIG. 1 is a block diagram showing a configuration of a digital camera according to an embodiment of the present invention. In the figure, a CCD unit 1 drives a CCD, which is a solid-state imaging device, to capture a subject image formed by an optical system, and outputs the captured image as an imaging signal. The image processor 2 performs image processing such as gamma correction and edge enhancement on image information of primary colors or complementary colors fetched from the CCD unit 1 and performs control such as automatic white balance and automatic exposure. The work memory 3 temporarily stores image data on which various image processes have been performed by the image processor 2. The JPEG module 4 converts the image data stored in the work memory 3 in response to the operation of a shutter key provided in a key block 5 composed of various operation keys and a shooting request from an external device (such as a personal computer). Compress. Key block 5
Is provided with various operation keys for instructing what kind of operation is to be performed. In particular, in the present embodiment, at least a function switch for switching between the REC mode and the PLAY mode is provided. The REC mode is an operation mode (video image acquisition function) for sequentially transmitting image data captured by the CCD unit 1 through the USB port 13 (video image input device:
Video Imaging Device). In the PLAY mode, a USB port 13 is provided between an external memory 6 described later and a PC.
Operating mode (storage image playback function) for transferring image data via the storage device (storage device: Mass Storage Clas)
s).

The external memory 6 is a removable storage medium such as a compact flash card or smart media, and records the compressed image data. Encoder 7
Converts a through image stored in the work memory 3 or a captured image recorded in the external memory 6 into a video signal. The LCD 9 is driven by the driver 8 and displays a video signal converted by the encoder 7 and setting items and settings in the setting mode. The memory controller 10 controls input and output of image data in the work memory 3 and the external memory 6 described above. CPU core 11
Is composed of a CPU, a ROM in which an operation program thereof, device information (storage device information, video image input device information) corresponding to each function, and the like are stored, and controls the operation of each unit including the memory controller 10. Particularly, in the present embodiment, the REC mode and the PLAY mode are operated in accordance with the operation of the function switch provided on the key block 5.
Controls switching between modes. In the switching control,
In addition to simply controlling the flow of data, in the REC mode, a video image input device (Video Imaging Device) is used.
ce) Set the device information to operate as
In the PLAY mode, a storage device (Mass Stora
ge Class) to set device information. Thereby, when there is a request for device information from a device connected via the USB port, the CPU core 11 transmits the set device information to the requested device. The RS232C port 12 is a data input / output I / O port having a relatively low communication speed.
The USB port 13 is an I / O port for inputting and outputting data at a high communication speed, and transfers a REC through image to a host (personal computer) (when recognized as a video image input device). Transfer an image file between the host and the external memory 6 (when the image file is recognized as a storage device).

FIG. 2 shows the USB port 13 described above.
FIG. 3 is a circuit diagram showing a detailed configuration of FIG. In the figure, CPU
The VBUSCNT terminal on the core 1 side is connected to the USB connector 15
This is an input port for detecting whether a USB cable is connected to the input port. When the USB cable is connected, the VCC terminal of the USB connector 15 becomes 5 V.
By checking the state of the NT terminal (input port), the presence or absence of a cable can be known. When the cable is connected and the USB connection application is ready,
By controlling the output terminal USBCNT terminal (output port)
The connection is notified to the host by pulling up the D + line by the resistor R3.

Next, FIG. 3 shows a processing procedure (Bus enumeration) after the USB device is connected to the host PC.
It is a conceptual diagram for explaining (device recognition method).
First, the digital camera which is a device waits with its address set to “0”. When notified of connection of a new device (digital camera in this case) as a USB device (S1), the host acquires a dummy device descriptor (S2). Next, assign an address to the digital camera that is a device (Set Addres
s) (S3), the digital camera as a device is configured as a device having a designated address. Next, the host issues a descriptor acquisition command (Get Descriptor) to the device whose address has been determined, and acquires various device information (S4). Descriptors include device descriptors (device class code and product ID, etc.), configuration descriptors (number of interfaces and power settings, etc.), interface descriptors (endpoint number and interface class), end pointers,
There is information on the descriptor (designation of bulk or isochronous transfer type). Lastly, upon completion of the recognition of the device class of the digital camera, which is the device, the host issues a configuration set command (Set Configuration) (S5), and loads a host-side device driver suitable for the connected USB device. And finish the work.
The operation by SB is started (S6).

Next, FIG. 4 is a conceptual diagram for explaining a device configuration when operating as a storage device.
The Mass Storage Class is a class that implements a file system via USB, and can handle a digital camera that is a device as a storage medium, such as a hard disk or a floppy (registered trademark) disk.
The control transfer (End Point (0)) sends a SCSI command to the device. Bulk transfer (End Point
(1), (2)) are used to send and receive file data,
Transfer large amounts of data where delay is not an issue. Also,
End Point (3) interrupt transfer is Write
Used for checking media after command execution.

Next, FIG. 5 is a conceptual diagram for explaining a device configuration when operating as a video image input device. In the Video Imaging Class, isochronous transfer is performed at End Point (4). This is used for continuous and periodic data transmission, and is used for sequentially transmitting REC through image data.

B. Next, an operation of the above-described embodiment will be described. FIG.
5 is a flowchart for explaining an operation when a USB cable is connected after or before power-on. Turn on the power (step S10), and then
When the B cable is connected (step S12), or with the USB cable connected (step S1)
4) In any case where the power is turned on (step S16), the mode shifts to the USB mode. Whether or not the USB cable is connected can be determined by checking the state of the VBUSCNT terminal.

Next, it is determined whether the function switch of the key block 5 is in the PLAY mode or the REC mode (step S18). When the function switch is in the PLAY mode, a device configuration (device information setting) is performed to operate the digital camera as a storage device (Mass Storage Class) (step S20). The host loads the device driver corresponding to the device configuration by acquiring the descriptor. After the end of the enumeration, the digital camera can operate as a storage device (Mass Storage Class).

On the other hand, when the function switch is in the REC mode, a device configuration (device information setting) is performed to operate the digital camera as a video image input device (Video Imaging Class) (step S2).
2). The host loads the device driver corresponding to the device configuration by acquiring the descriptor. Thereafter, the digital camera can sequentially transmit images captured by the CCD unit 1 to the host via the USB port 13.

Next, FIG. 7 is a flowchart for explaining the operation when the function switch is switched while the USB is connected. When the switch of the function switch is detected during the USB connection (step S3
0), USB required as application software
End processing is performed (step S32). Next, USBCN
By controlling the T signal, the pull-up of the D + line was once released, the USB connector 15 was once disconnected from the bus, and then the D + line was pulled up again to reconnect the USB cable. The state is set (step S34).

Next, it is determined whether the function switch of the key block 5 is in the PLAY mode or the REC mode (step S36). When the funk place switch is in the PLAY mode, a device configuration (device information setting) is performed to operate the digital camera as a storage device (Mass Storage Class) (step S38). The host loads the device driver corresponding to the device configuration by acquiring the descriptor. After the end of the enumeration, the digital camera can operate as a storage device (Mass Storage Class).

On the other hand, when the function switch is in the REC mode, a device configuration (device information setting) is performed to operate the digital camera as a video image input device (Video Imaging Class) (step S4).
0). The host loads the device driver corresponding to the device configuration by acquiring the descriptor. Thereafter, the digital camera can sequentially transmit images captured by the CCD unit 1 to the host via the USB port 13.

In this embodiment, a general-purpose device driver can be used as a device driver on the host.
Without using a large-capacity memory, USB function development on the USB device side can be performed separately for each function.

In the above embodiment, the connection means is USB
The connection means is not limited to this, but may be, for example, a wireless connection. In addition, as long as the electronic device is connected to another electronic device and has a plurality of device functions, the electronic device is not limited to a digital camera and may be any electronic device.

[0024]

According to the first aspect of the present invention, the function switching means switches the function to a predetermined function among the plurality of functions stored in the storage means, and the function setting means switches the function to the switched function by the device setting means. The corresponding device information is read from the storage unit and set, and when requested by another electronic device, the transmission unit transmits the device information set by the device setting unit to the other electronic device. Therefore, in an electronic device having a plurality of functions, there is an advantage that a connection partner electronic device can easily recognize device information corresponding to the plurality of functions.

According to the second aspect of the present invention, the device setting means sets the device information corresponding to the function when the connection to the another electronic device is detected by the detecting means. Therefore, in an electronic device having a plurality of functions, there is obtained an advantage that a connection partner electronic device can easily recognize device information corresponding to the plurality of functions.

According to the third aspect of the invention, the device setting means sets device information corresponding to a function when the power is turned on by the power supply means, and thus has a plurality of functions. In the electronic device, there is an advantage that the connection partner electronic device can easily recognize the device information corresponding to the plurality of functions.

According to the fourth aspect of the present invention, when the function is switched by the function switching unit during connection with the another electronic device, the device setting unit connects to the other electronic device. Once the device information has been disconnected, device information corresponding to the switched function is set, so that in an electronic device having a plurality of functions, the device information corresponding to the plurality of functions can be easily recognized by a connection partner electronic device. This has the advantage of being able to

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a digital camera according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a detailed configuration of the USB port 13 described above.

FIG. 3 is a conceptual diagram illustrating a processing procedure after a USB device is connected to a host.

FIG. 4 is a conceptual diagram illustrating a device configuration based on a Mass Storage Class.

FIG. 5 is a conceptual diagram for describing a device configuration based on a Video Imaging Class.

FIG. 6 is a flowchart for explaining an operation when a USB cable is connected after power-on or before power-on.

FIG. 7 is a flowchart illustrating an operation when a function switch is switched while a USB is connected.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CCD unit 2 Image processor 3 Work memory 4 JPEG module 5 Key block (function switching means, power supply means) 6 External memory 7 Encoder 8 Driver 9 LCD 10 Memory controller 11 CPU core (storage means, device setting means) 12 RS232C port 13 USB port (transmission means, detection means)

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H04N 5/232 H04N 5/232 Z 5/765 101: 00 5/781 5/781 510C // H04N 101: 00

Claims (4)

[Claims] 1. An electronic device connected to another electronic device and transmitting device information based on a request from the other electronic device, wherein: a storage unit for storing device information corresponding to a plurality of functions; A function switching unit for switching a function to a predetermined function among the functions; a device setting unit for reading and setting device information corresponding to the function switched by the function switching unit from the storage unit; and a request from the another electronic device. An electronic apparatus, comprising: a transmitting unit that transmits device information set by the device setting unit. 2. The device setting means includes a detecting means for detecting a connection to the another electronic device, and setting device information corresponding to a function when the connection is detected by the detecting means. The electronic device according to claim 1, wherein: 3. A power supply unit for turning on a power supply of an electronic apparatus, wherein the device setting unit sets device information corresponding to a function when the power supply unit is turned on. Item 6. The electronic device according to Item 1. 4. When the function is switched by the function switching unit during connection with the another electronic device, the device setting unit disconnects the connection with the other electronic device and then switches the function. 2. The electronic apparatus according to claim 1, wherein device information corresponding to the electronic device is set.