JP2016025593A - Image display device and image display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image display device etc. capable of simple and stable image display even when using a USB cable for a transmission interface between an image output device for outputting image data and the image display device for displaying the image data.SOLUTION: Transmitting means and receiving means are interconnected through a connection line by USB connection. It is determined whether the transmitting means and the receiving means are interconnectable with a V-by-One HS signal. If transmission is possible with the V-by-One HS signal, image data is transmitted from the transmitting means to the receiving means through the connection line and the received image is displayed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a device that outputs image data, and an image display device that uses a USB cable as a transmission interface between the devices that input and display image data.

  Conventionally, when displaying image data on a display device (for example, an LCD (Liquid Crystal Display) display device, an organic EL display, etc.), as a digital IF for connecting the video output device and the display device, DVI (Digital Visual Interface) ), HDMI (registered trademark) (High-Definition Multimedia Interface), and Display port.

  In recent years, USB (Universal Serial Bus) is generally used as an interface for transferring data in various information processing apparatuses such as computers, smartphones, and tablets. When image data is transmitted using the USB-IF, it is realized by converting the USB into the digital IF and transferring it (for example, see Patent Document 1).

JP 2008-9253 A

  Here, in a display device using a USB-IF, a new device driver is required to display an image. In this case, in order to output from the USB-IF, software image processing is required. Therefore, depending on the performance of the CPU (Central Processing Unit), there have been problems such as a drop in display frames and a decrease in the speed of other CPU processes.

  For example, even in the above-described Patent Document 1, since it is realized by a driver for image transfer, the processing of the CPU is affected, and there is a problem that a stable system cannot be provided.

  Further, when viewed from the manufacturer side, if an interface such as DVI, HDMI (registered trademark), or Display port is newly provided, the number of IF ports increases, which limits the size reduction of the apparatus. There was a point.

  Furthermore, considering the manufacturing cost, the above-described interface has a problem that a separate license fee is required and the cost of the connection harness is excessive.

  Therefore, in view of the above-described problems, the present invention is simple and stable even if a USB cable is used as a transmission interface between an image output device that outputs image data and an image display device that displays image data. An object is to provide an image display device capable of displaying an image.

In order to solve the above-described problems, an image display device according to the present invention includes:
A transmission means for transmitting data;
Receiving means for receiving data;
A connection line for connecting the transmission means and the reception means by USB connection;
A determination unit that determines whether the transmission unit and the reception unit can be connected by a V-by-One HS signal;
A control means for controlling transmission of image data from the transmission means to the reception means via the connection line when the determination means enables transmission using a V-by-One HS signal;
Display means for displaying an image received by the receiving means;
It is characterized by providing.

The image display system of the present invention includes:
An image display system including an image transmission device that transmits an image and an image display device that receives and displays the image,
The image device and the image display device are connected by a connection line,
The image transmission device includes:
A determination means for determining whether the image display device is connectable by a V-by-One HS signal;
When the determination unit can transmit a V-by-One HS signal, the image transmission unit transmits an image to the image display device via the connection line;
With
The image display device includes image display means for receiving and displaying an image via the connection line.

  According to the present invention, it is possible to display an image on a display device (for example, an LCD) via a conventional connection line (for example, a USB cable) using a V-by-One HS signal transmission interface.

  In addition to having a function of displaying an image using an existing USB connector, it can also be used as a normal USB device function, and the function can be automatically switched depending on a connected device.

1 is an external view showing the entire system in the present embodiment. It is a figure for demonstrating the function structure in 1st Embodiment. It is a flowchart explaining the flow of the process in 1st Embodiment. It is a figure for demonstrating the function structure in 2nd Embodiment. It is a figure for demonstrating the function structure in 3rd Embodiment. It is a flowchart explaining the flow of the process in 3rd Embodiment. It is a flowchart explaining the flow of the process in 3rd Embodiment. It is a figure for demonstrating 4th Embodiment.

  The best mode for carrying out the present invention will be described below with reference to the drawings. For convenience of explanation, the embodiment will be described as an example, but it is needless to say that any device can be applied as long as the device can perform a display operation.

[1. First Embodiment]
FIG. 1 shows an image display system 1 to which the present invention is applied. In the image display system 1, an image transmission device 10 as an image output device and an image reception device 20 as an image display device are connected via a cable. The image includes a moving image and a still image. For example, a 3D image is also included as long as it is displayed as a video on the display device.

  Here, in order to display (transfer) an image, a V-By-One HS developed by Thine is used for an IF (image receiving apparatus 20) between the data transmitting side (image transmitting apparatus 10) and the data receiving side. Is used.

  Here, V-By-One HS is a standard that enables transmission of a video signal using only a differential one-pair cable. High-speed data communication is possible without imposing a burden on the CPU. In addition to SerDes, V-By-One HS incorporates technologies such as clock data recovery to solve the problem of skew while realizing high-speed transmission of 3.75 Gbps per pair, as well as EMI and consumption. Power is being reduced. In addition, the total cost of cables and connectors can be reduced by reducing the number of transmission pairs.

  The specification of V-by-One HS is disclosed by the developer, Thine, and there is an advantage that the license is only a contract and there is no cost.

  Here, regarding the IF of the transmission line, communication is possible if the cable has a differential impedance of 100Ω. Therefore, a USB cable can be used as the transmission cable. In the present embodiment, the cable 15 is connected using a USB cable.

  Next, an outline of a functional configuration in the present embodiment will be described with reference to FIG. In FIG. 2, the image transmission device 10 and the image reception device 20 are connected via a cable 15.

  The image transmission apparatus 10 has an image data storage area 102 for storing image data, and realizes an image data transfer control apparatus 104 that performs image data transfer processing and a V-by-One HS transmission function. As an IC to be used, a V-by-One HS transmission function IC 106 is included.

  Further, a transmission connector 108 is provided, and the cable 15 is attached. In the present embodiment, the USB connector (for example, a signal cable for USB 3.0) is used for the transmission connector 108 and the cable 15.

  The image receiving device 20 is also provided with a transmission connector 256. Then, the transmission connector 108 and the transmission connector 256 are connected via the cable 15. That is, the transmission connector is an interface in the present embodiment and indicates a USB connection connector.

  Further, the image receiving device 20 is provided with a V-by-One HS receiving function IC 254, extracts an image signal from the received signal, and outputs the image signal to the display device 252. Then, an image is displayed on the display device 252.

(Process flow)
Next, the flow of processing in the first embodiment will be described with reference to FIG.

  First, it is detected whether or not cable connection is made between devices (step S102). When the cable is connected, that is, when transmission / reception is possible (step S102; Yes), start-up processing of the V-by-One HS on the transmission / reception side is started (step S104). That is, the V-by-One HS ICs of both devices perform start-up processing based on the standard.

  This start-up process is a process necessary for recognizing whether or not both can be transmitted according to the V-by-One HS standard, and the V-by-One HS IC (V-by-One HS transmission function IC 106). , V-by-One HS reception function IC 254) is automatically performed.

  When the startup process is completed normally (step S106; Yes), the V-by-One HS transmission function IC 106 of the image transmission apparatus 10 can transfer data. Therefore, the image data transfer control device 104 outputs the image data stored in the image data storage area 102 to the V-by-One HS transmission function IC 106.

  The V-by-One HS transmission function IC 106 transfers the image to the V-by-One HS reception function IC 254 via the (USB) cable 15 (step S108).

  Here, when the V-by-One HS reception function IC 254 receives the image data, the received image data is displayed on the display device 252 (step S110).

  For data between the control device (image data transfer control device 104) on the transmission side and the V-by-One HS, the image data is converted to LVDS by using LVDSIF IP as a hard macro in the control device. (Low Voltage Differential Signaling) can be converted.

  Further, when transferring data from the image data storage area 102 in the image data transfer control device 104, by providing a DMA (Direct Memory Access) function, it is possible to transfer data without affecting the software load. . Therefore, it is possible to reduce the software load in the entire transmission / reception of image data.

[2. Second Embodiment]
Next, the second embodiment will be described. In the second embodiment, a case where an image display device with a USB interface to the outside of the device is not used will be described. That is, the display device is an integrated device.

  FIG. 4 illustrates a functional configuration of the display device 30 in the second embodiment. The same functional components as those in the functional configuration shown in FIG. 2 are denoted by the same reference numerals, and the description thereof is omitted.

  That is, in a device in which the display device is integrated with the image transmission device, a harness is connected inside the device. The transmission connector 302 and the transmission connector 304 can be realized by an internal connection interface, and the transmission cable 17 is also used inside the apparatus. The transmission cable 17 uses a USB cable as in the first embodiment.

  Furthermore, in the case of the apparatus according to the second embodiment, the USB port is not necessary when the sub display is not used. In that case, it is possible to reduce the cost by deleting the USB port to the outside and reduce the influence of static electricity and the like.

  As described above, in the communication inside the apparatus, the USB cable can be used for the internal harness even when the connection using V-by-One HS is performed.

[3. Third Embodiment]
Next, a third embodiment will be described. In the third embodiment, an image display device to an external USB interface is also possible, and when the external display device is not used, when the other USB device is connected, the USB device is automatically recognized. An embodiment to be used will be described.

  FIG. 5 is a diagram illustrating a functional configuration according to the third embodiment. In addition, the same code | symbol is attached | subjected to the function structure substantially the same as the figure of the function structure shown in FIG.

  In FIG. 5, a connection connector 404 (connection connector 452) is provided. This connection connector has the same configuration as the transmission connector according to the first embodiment, and is an IF to which a USB (USB 3.0 in this embodiment) cable 15 can be connected.

  The difference from the first embodiment is that the connection connector is a general-purpose connector. That is, another USB device (for example, a USB memory) can be connected to the connection connector 404 of the image transmission device 40. In this case, the V-by-One HS transmission function IC 106 detects that the device is not a V-by-One HS device and notifies the image data transfer control device 104 of it.

  The image data transfer control device 104 sends a control signal to the USB switch 402, and the signal line is switched by the USB switch.

(Process flow)
Specific processing will be described with reference to FIG. In addition, the process in this figure attaches | subjects the same code | symbol as the process in 1st Embodiment, and abbreviate | omits the detailed description.

  That is, start-up processing of the V-by-One HS on the transmission / reception side is started (step S104), and it is determined whether the start-up processing is completed (step S106). Here, when the start-up process is not completed (step S106; No), the V-by-One HS transmission function IC 106 on the transmission side indicates that the other party connected to the connection connector 404 is a device compatible with V-by-One HS. Judge that is not.

  Then, the image data transfer control device 104 is notified (step S202). Some V-by-One HS ICs have a GPIO function, and can be used for this notification.

  Further, it can be determined that the connected device is not a compatible device, for example, by not detecting the LOCKN signal.

  Here, when it is determined that the connected device is not a compatible device, it may be switched and used as a USB device. For example, as shown in FIG. 7, after step S202, USB initialization processing is executed (step S252).

  When the USB initialization is completed, the USB device class is confirmed (step S254). Thereby, when there is a device driver corresponding to the connected USB device (step S256; Yes), the connected USB device can be used (step S258).

  Note that the USB-IF signal for V-by-One HS and USBIF signals other than V-by-One HS are output by the image data transfer control device using control ICs and using an IC having a USB switch function. This can be realized by switching the signal line switch.

  As described above, according to the present embodiment, one of the USB ports for connecting an external device or the like can be used as a V-by-One HS port. In addition, the V-by-One HS port can be used as a general-purpose USB port.

[4. Fourth Embodiment]
Subsequently, a fourth embodiment will be described. In the above-described embodiment, the USB 3.0 has been described. However, for example, it may be realized using the USB 2.0. Here, the relationship between the USB signal line and the V-by-One HS signal line is shown in FIG.

  For example, as shown in FIG. 8A, the number of lanes is required for the resolution and the image refresh rate.

  For example, when the resolution is “1920 × 1080” and the refresh rate is 60 Hz, the necessary number of lanes is “2”.

  Here, FIG. 8B shows a usage method in the case of USB 2.0, and FIG. 8C shows a usage method in the case of USB 3.0. When a USB 2.0 cable is used, one lane number can be secured, and when a USB 3.0 cable is used, two lane numbers can be secured.

When the signal line of V-by-One HS is 1 lane, it can communicate HDTV level with a resolution of 720p (1280 × 720) at a refresh rate of 60 Hz.
・ 1 pair of differentials (2)
・ HTPDN (HotPlugDetect: Hot plug detection)
・ LOCKN (Lock Detect)
It consists of a total of four. LOCKN is a signal asserted by the receiving side and indicates that the startup process has been completed at Low.

  HTPDN is a signal asserted by the receiving side, and indicates that the device is active at Low.

  Since HTPDN is an option and does not need to be used, it can be realized with a minimum of three signal lines. However, in order to maintain the same potential between devices, a total of four GND terminals are required.

  The V-by-One HS communication line can be of any type as long as it is a cable matched with a differential impedance of 100Ω, and for example, a USB cable can be used.

  Therefore, in the configuration of one lane, four cables are necessary, so a USB 2.0 cable can be used. As shown in FIG. 8B, this can be realized by connecting D + and D− to the differential line, connecting LOCKN to the Vbus terminal, and connecting to the GND terminal. However, since the bit rate of the V-by-One HS lane is 600 Mbps to 3.75 Gbps and USB 2.0 is 480 Mbps, transmission with signal quality may not be possible.

  On the other hand, USB 3.0 has a bit rate of 5 Gbps according to the standard and satisfies the specification of V-by-One HS. In addition, the USB 3.0 cable has a total of nine signal lines including three differential pairs, two GNDs, and one Vbus, so the number of lanes of V-by-One HS can be increased.

  V-by-One HS devices are available in two lane types, and can be combined with a USB 3.0 cable to increase the refresh rate and to support full-HDTV levels with a resolution of 1080p (1920 x 1080). It is.

  According to the above-described embodiment, it is possible to display an image on an LCD or the like via a USB harness using a signal transmission interface of V-by-One HS. In addition to having a function of displaying an image using an existing USB connector, it can also be used as a normal USB device function, and the function can be automatically switched depending on a connected device.

[5. Modified example]
The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and the design and the like within the scope of the present invention are also within the scope of the claims. include.

  In addition, the program that operates in each device in the embodiment is a program (a program that causes a computer to function) that controls the CPU and the like so as to realize the functions of the above-described embodiments. Information handled by these devices is temporarily stored in a temporary storage device (for example, RAM) at the time of processing, then stored in various ROM or HDD storage devices, and read and corrected by the CPU as necessary. • Writing is performed.

  Here, as a recording medium for storing the program, a semiconductor medium (for example, ROM, a non-volatile memory card, etc.), an optical recording medium / a magneto-optical recording medium (for example, a DVD (Digital Versatile Disc), MO (Magneto Optical), etc. Disc), MD (Mini Disc), CD (Compact Disc), BD, etc.), magnetic recording medium (eg, magnetic tape, flexible disk, etc.), etc. In addition, by executing the loaded program, not only the functions of the above-described embodiment are realized, but also based on the instructions of the program, the processing is performed in cooperation with the operating system or other application programs. The functions of the invention may be realized.

  In addition, when distributing to the market, the program can be stored and distributed in a portable recording medium, or transferred to a server computer connected via a network such as the Internet. In this case, of course, the storage device of the server computer is also included in the present invention.

  In addition, a part or all of each device in the above-described embodiments may be realized as an LSI (Large Scale Integration) that is typically an integrated circuit. Each functional block of each device may be individually chipped, or a part or all of them may be integrated into a chip. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, when integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, it is of course possible to use an integrated circuit based on this technology.

DESCRIPTION OF SYMBOLS 10 Image transmission apparatus 102 Image data storage area 104 Image data transfer control apparatus 106 V-by-One HS transmission function IC
108 Transmission connector 15 Cable 20 Image receiving device 252 Display device 254 V-by-One HS receiving function IC
256 Transmission connector

Claims (4)

A transmission means for transmitting data;
Receiving means for receiving data;
A connection line for connecting the transmission means and the reception means by USB connection;
A determination unit that determines whether the transmission unit and the reception unit can be connected by a V-by-One HS signal;
A control means for controlling transmission of image data from the transmission means to the reception means via the connection line when the determination means enables transmission using a V-by-One HS signal;
Display means for displaying an image received by the receiving means;
An image display device comprising: Further comprising transmission control means for controlling transmission of data by the transmission means;
The image display apparatus according to claim 1, wherein the control unit notifies the transmission control unit when the determination unit determines that transmission is not possible using a V-by-One HS signal.   3. The image display device according to claim 1, wherein when the USB device is connected to the transmission unit, the control unit recognizes the USB device and performs usable control. 4. An image display system including an image transmission device that transmits an image and an image display device that receives and displays the image,
The image device and the image display device are USB-connected by a connection line,
The image transmission device includes:
A determination means for determining whether the image display device is connectable by a V-by-One HS signal;
When the determination unit can transmit a V-by-One HS signal, the image transmission unit transmits an image to the image display device via the connection line;
With
The image display system includes an image display unit that receives and displays an image via the connection line.

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