JP2002312155A - System for communicating from/to terminal via wire connection channel and wireless connection channel, arithmetic processing unit, wireless connection terminal, method for transferring data to wireless connection terminal, program, and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly switch between a wire connection and a wireless connection, when a system is equipped with a wire connection channel and with a wireless connection channel between the system and a terminal. SOLUTION: Communication between a display device 50 and an arithmetic processing unit (host) 10 is provided with two connection modes, a wire connection mode for communication via the wire connection channel 20 and a wireless connection mode for communication via the wireless connection channel 30. Before entering the wireless connection mode, the processing unit (host) 10 sends out information needed for the wireless connection from/to the display device 50 via the connection channel 30 and information necessary for authentication for allowing access of information, using the connection channel 30 to the display device 50 via the connection channel 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system having a wired connection path and a wireless connection path with a terminal such as a display device, and more particularly, to a smooth switching between a wired connection and a wireless connection. The present invention relates to a system and the like that enables the above.

[0002]

2. Description of the Related Art In recent years, for example, there has been a product provided with a monitor which can be easily carried while enjoying mail communication and the Internet easily. This product includes, for example, a base station and a portable liquid crystal monitor, so that users can enjoy the Internet and e-mail communication by wireless communication if they move around the house with only the monitor.

In such conventional products, WWW (World
It has a browser function of Wide Web, and the server is HTML
It is configured to communicate by a protocol and receive a display protocol, and the connection destination is generally limited to a WWW server. Also, software built in the display terminal in advance is limitedly connected only to the corresponding host. Furthermore, it does not have a display function and performance comparable to those of a wired connection.

[0004]

Now, consider a display device having two connection modes, a wired connection and a wireless connection. For example, when the display device is located near the computer (host) to which the display device is connected, the two devices are connected and connected by wire to ensure the same display speed as that of a conventional wire display device. On the other hand, when they are separated from each other, a wireless connection is made to ensure a variety of operation modes.

Here, as a device having two connection modes of a wired connection and a wireless connection, for example, a base called a cradle is provided, and a terminal is placed on the cradle to be in a wired connection mode, and is lifted from the base. Devices that are in wireless mode can be considered. In the case of such a device, it is expected that the mode is switched frequently between wireless and wired modes. However, authentication work such as inputting a password at the time of connection, such as a general remote connection via a network, is expected. If it becomes necessary, the convenience provided by providing two connection modes will be impaired.

[0006] At present, a technology for constantly transferring a screen image in synchronization with its refresh cycle is used for a cable connecting a host and a monitor such as a CRT. For example, if the screen size is XGA (Extended Graphics A
(rray), when the data amount per pixel is 16 bits and the refresh rate is 60 Hz, the overall data rate is about 750 Mbps. On the other hand, at present, in a general wireless LAN, the transfer rate is a maximum of 11 Mbps, so that data in the same format used for wired connection cannot be transferred by wireless connection.

Further, a method of transferring a screen drawing command (primitive) instead of a screen image and developing it into an image on the display device side, or transferring only the difference of the screen image on the host side is conceivable. According to these methods, while the screen drawing frequency is low, the response of the screen update on the display device side is good, but when a large amount of drawing is performed,
As in the image transfer method, the transmission path becomes a bottleneck. A method of transferring only the screen image difference on the host side is conceivable, but it is difficult to detect the image difference. For example, if the difference is simply obtained by software, it itself becomes overhead.

Furthermore, a method of processing a large number of drawing commands at high speed on the host side and sending snapshots of the screen (or difference images between the snapshots) to the display device at appropriate intervals can be considered. However, in such a method, when the drawing frequency is relatively low, the drawing response deteriorates as compared with the drawing primitive method.

The present invention has been made in order to solve the above technical problems, and a purpose thereof is to automatically perform settings required at the time of wireless connection,
It is to enable smooth switching between a wired connection and a wireless connection. It is another object of the present invention to secure a real-time property even when a large amount of drawing is performed, while ensuring a response of a primitive method by a screen drawing command.

[0010]

With this object in mind, according to the present invention, in the wired connection mode, the wired connection path connecting the arithmetic processing unit and the terminal is a one-to-one connection,
Focusing on the fact that it can be regarded as a secure communication path, and that the wired connection path and the wireless connection path can be used simultaneously without being exclusive, and communication between a terminal such as a display device and a processing unit which is a host. Has two connection modes, a wired connection mode in which communication is performed via a wired connection path, and a wireless connection mode in which communication is performed through a wireless connection path, and transfers information necessary for the wireless connection mode in the wired connection mode. are doing.

That is, in the system to which the present invention is applied, the arithmetic processing unit comprises: a wired communication means for communicating with the terminal via a wired connection path; and a communication means for communicating with the terminal via a wireless connection path via a wireless connection path. Sending means for sending information required at times and information necessary for authentication for permitting access to information using a wireless connection path to a terminal using a wired communication means before entering a wireless connection mode. It is characterized by having.

Here, attaching / detaching means for attaching / detaching the terminal, which is provided directly or indirectly to the arithmetic processing unit.
(E.g., a cradle or the like),
Detecting means for detecting that a terminal has been attached to or detached from the attaching / detaching means, and switching means for switching between communication via a wired connection path and communication via a wireless connection path based on the detection result. The feature is preferable because, for example, a wired connection mode in which functions, performance, and operability equivalent to those of a conventional terminal are maintained and a wireless connection mode in which convenience is enhanced can be appropriately switched.

From another viewpoint, the present invention is characterized in that a plurality of display data transfer methods are dynamically switched according to some characteristic amount. For example, the display data transfer method is changed according to the characteristics of data to be displayed. The system is being switched.
That is, the present invention is a system including a display device and an arithmetic processing device that performs communication between the display device and the display device via a wireless connection path. A first transfer unit that transfers data to the display device using a primitive-based drawing instruction protocol, and a second transfer device that transfers data to the display device using a protocol that sends an image image as snapshot image difference information. Means, and switching means for switching between the first transfer means and the second transfer means based on a predetermined characteristic amount.

Here, the predetermined characteristic amount may be at least one of a data size on the communication path, a change amount, an effective bandwidth of the network, and a drawing performance of the display device. This makes it possible to ensure practically sufficient display performance even in the wireless connection mode in which the data transfer capability is inferior to that in the wired connection mode.

Further, after receiving the drawing command, the second transfer means determines whether or not to transmit the screen image based on a predetermined index. It is characterized in that an image based on the transmitted area to be transmitted is transmitted. Here, the predetermined index is, when the amount of change of the screen image exceeds the set value,
At least one of a case where a set number or more of drawing instructions are processed, a case where a set time has elapsed since the last transmission of the image, and a case where a transmission request from the display device is received. This is advantageous in that efficient transfer of image data can be performed.

Of course, the present invention can be understood as a host device and an arithmetic processing device. That is, the present invention
An arithmetic processing device (host device) that has a wired connection mode and a wireless connection mode and communicates with a terminal, a wired communication unit that communicates with the terminal via a wired connection path, and a wireless connection path. A wireless communication means for performing wireless communication with the terminal through the wireless communication means, and before communication with the terminal by the wireless communication means,
Sending means for sending information required at the time of communication via the wireless connection path to the terminal using the wired communication means, determining means for determining whether the terminal has left the wired connection path,
Switching means for switching to wireless communication via a wireless connection path based on the wireless communication means when it is determined by the determination means that the mobile phone has been disconnected.

An arithmetic processing unit to which the present invention is applied includes a CPU, a graphics adapter for generating image data based on a drawing command, and a frame memory for expanding the image data generated by the graphics adapter. A wireless communication device for transmitting data for drawing to a display device in a transfer mode using a drawing primitive, and the CPU determines whether or not to transmit an image based on a predetermined index. At the same time, the area to be transmitted is calculated and the image image is read from the frame memory, and the wireless communication apparatus transfers the read image image data via the wireless connection path instead of the transfer mode using the drawing primitive. Sending to display device.

Here, if the CPU calculates the area to be transmitted based on a change in data in the image image expanded in the frame memory, for example, when transferring all image images, In comparison, even if the data size is reduced, sufficient display performance can be ensured in practical use.

On the other hand, the present invention can be understood as a terminal such as a display device. That is, the present invention is a wireless connection terminal that communicates with an arithmetic processing device via a wired connection path and a wireless connection path, and a wired communication unit that communicates with the arithmetic processing device via a wired connection path, Wireless communication means for communicating with the processing unit via a wireless connection path, wherein the wired communication means is required for communication via the wireless connection path prior to communication via the wireless connection path. Information and information necessary for authentication at the time of communication via a wireless connection path are received via a wired connection path.

Here, the wireless communication means can wirelessly transfer an authentication request based on information necessary for authentication received by the wired communication means to the arithmetic processing unit. A detecting unit that detects whether or not the wired connection path has been disconnected; and based on the detection by the detecting unit, stops data communication by the wired communication unit and performs communication by the wireless communication unit. It can be a feature. Further, a developing means such as a graphics adapter for developing an image in a frame memory based on data received via a wireless connection path, and a display panel or the like for reading and displaying the image developed in the frame memory Means are further provided.

According to another category, the present invention relates to a data transfer method for performing communication between an arithmetic processing unit and a terminal via a wired path and a wireless path, wherein the terminal is connected to the wired path. When the terminal is connected to the wired path, information required for wireless connection in communication via the wireless path is transferred in advance through the wired path to determine whether the terminal is necessary for the wireless connection. The authentication is performed.

Here, paying attention to the fact that the wired connection cable and the wireless link can be used simultaneously, but not exclusively, the session ID is transferred from the arithmetic processing unit to the terminal via the wired path, and the session ID is transmitted from the terminal via the wireless path. The session ID
Is transferred to the arithmetic processing unit.

The present invention also relates to a data transfer method for performing communication between a display device and an arithmetic processing device via a wireless path, wherein the method detects a predetermined characteristic amount in communication via the wireless path and detects the characteristic amount. A first transfer method for performing transfer to a display device by a drawing primitive-based drawing instruction protocol including a screen drawing command based on the obtained feature amount;
It is characterized by switching between a second transfer method for transferring to a display device by a protocol for transmitting an image image as difference information of a snapshot of a screen image.

Incidentally, these configurations of the present invention can be understood as programs for realizing these functions on a computer. These computer programs can be provided, for example, from a remote program transmission device to a computer, which is an arithmetic processing device, via a network. As the program transmission device, a CD storing a program is used.
A configuration including storage means such as a ROM, a DVD, a memory, and a hard disk; and a transmission means for reading a program from these storage means and transmitting the program via a network such as the Internet or a LAN to a device that executes the program. It is good.

Further, these computer programs can be directly provided by a storage medium such as a CD-ROM and a DVD. In such a case, a computer such as a PC on which the program is installed only needs to have a function of reading a storage medium (CD-ROM drive, DVD drive, etc.).

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings. FIG. 1 is a diagram for explaining a schematic configuration of a system according to the present embodiment. A system to which the present embodiment is applied includes, for example, an arithmetic processing device (host) 10 that performs image processing and outputs image image data, and a wired connection path to the arithmetic processing device 10.
A cradle 40 electrically connected through a (wired connection line) 20 and a display device 50 as a wireless connection terminal (terminal) detachably attached to the cradle 40 are provided.

Although the cradle 40 is a stand-type docking station, the arithmetic processing unit 10 and the cradle 40 are integrated in the same housing, and the arithmetic processing unit 1
Alternatively, the display device 50 may be configured to be directly attachable / detachable to / from the device 0, and the wired connection path 20 may be provided inside the housing. That is, as shown in FIG. 1, when the wired connection path 20 is exposed outside the arithmetic processing device 10 and the cradle 40 is provided separately from the housing of the arithmetic processing device 10, the cradle 40 is connected to the arithmetic processing device 10. Is "indirect"
It will be provided in. On the other hand, if the casings are the same, it can be said that they are provided “directly”.

FIG. 2 is a block diagram showing the overall configuration of the system according to the present embodiment. The cradle 40 has a connector 41, and the display device 50 has a connector 5.
1 is provided. The display device 50 is physically connected to the cradle 40 by attaching the connector 51 to the connector 41.
Are electrically coupled to each other. As a result, the arithmetic processing device 10 and the display device 50 are connected by the wired connection path 20. Further, even when the display device 50 is detached from the cradle 40, the display device 50 is logically connected by the wireless connection path 30 and can exchange wireless image information and wireless data.

FIG. 3 is a block diagram further detailing the system configuration in the present embodiment. Wired connection path 20
Is composed of a wired data transfer line 21 and a wired image transfer line 22. The wired data transfer line 21 bidirectionally transfers information other than an image in communication between the arithmetic processing device 10 and the cradle 40. The wired image transfer line 22 receives image information from the arithmetic processing device 10 and transfers the image information to the cradle 40. As the wired connection path 20, for example, a combination of a display cable using a coaxial cable and a USB (Universal Serial Bus),
DVI (Digital Visual Interface) using stranded wires
Cable and the like. Since a normal video connection cable has a two-way communication path in addition to the video signal,
Although it can be used as a control line, for example, in the case of analog RGB, in addition to the video cable,
A control cable can be used in combination with a B cable or the like.

The arithmetic processing unit 10 includes a CPU 11 for controlling the entire apparatus, and a main memory 1 for the operation of the CPU 11.
2. Graphics adapter 1 for generating images
3. Frame memory 14 for expanding image data generated by graphics adapter 13, Wired connection path 2
0, and the wireless communication device 1 that exchanges data via the wireless connection path 30
6 is provided. In the present embodiment, the user installs the display device control software on the arithmetic processing device 10 serving as the host in advance. The display device control software may be installed in advance when the arithmetic processing device 10 is purchased, or may be provided via a storage medium such as a CD-ROM, or may be downloaded via a network such as the Internet. There is. The display device control software includes a portion that controls connection of a terminal (display device 50),
It is divided into a part for controlling the drawing information in the wireless mode.

The display device control software monitors whether or not a terminal (display device 50) is connected to the arithmetic processing device 10, which is a host. When the display device 50 is connected, the display device control software enters a wired connection mode. The video signal is sent to the display device 50 via the wired image transfer line 22. Further, the display device control software sends various information necessary for wireless connection to the display device 50. If necessary, the information necessary for authentication is sent to the display device 50 by referring to the identifier of the connected display device 50. When disconnected from the cradle 40, the mode transits to the wireless connection mode, and screen information is transmitted via the wireless connection path 30 which is a wireless link.

In the wired connection mode in which communication is performed via the wired connection path 20, the CPU 11
A drawing primitive that is a screen drawing command that is transferred instead of a screen image, such as a rectangle or line segment, to display the contents to be displayed, as a result of performing some processing using the data.
(Primitive) to the graphics adapter 13. The graphics adapter 13 stores the frame memory 1 according to the contents of the received drawing primitive.
4, an image is generated. The graphics adapter 13 periodically reads out the generated image image and sends the read image image to the wired communication device 15. Further, the wired communication device 15 sends out the image received from the graphics adapter 13 to the wired image transfer line 22.

In the wireless connection mode in which communication is performed via the wireless connection path 30, the CPU 11 first generates an image on the frame memory 14 as in the wired connection mode. Further, the generated image data is transferred to the display device 50 via the wireless communication device 16.
Alternatively, some processing is performed using the command / data in the main memory 12, and as a result, the content to be displayed is converted into a drawing primitive format, and then the drawing primitive is converted to a display device via the wireless communication device 16. 50.

The wireless communication device 16 transmits and receives data to and from a wireless communication device (described later) on the display device 50 side.
An example of the wireless communication device 16 is IEEE 802.11
Such as wireless LAN, Bluetooth (Bluetooth)
And the like. The wired data transfer line 21 also transmits and receives data between the arithmetic processing device 10 and the display device 50. As an example of the wired data transfer line 21, DDC (D
isplay Data Channel) and USB.

FIG. 4 is a block diagram for explaining the cradle 40. The cradle 40 includes a connector 41 and a detachment detection device 42, and
1 and the signal received from the wired image transfer line 22 are transmitted to the display device 50 via the connector 41. The attachment / detachment detection device 42 electrically detects that the display device 50 has been attached / detached to / from the cradle 40 and sends the information to the arithmetic processing device 10 through the wired data transfer line 21. As a method of detecting attachment / detachment by the attachment / detachment detection device 42, for example, there is a method using a mechanical switch. Also, the connector 41
For example, a method of monitoring a signal line for exchanging information with the display device 50 via the PC and detecting a signal level of the signal line can be considered.

The attachment / detachment detecting device 42 may be provided not inside the cradle 40 but inside the arithmetic processing unit 10. In such a case, the CPU 11 of the arithmetic processing unit 10 periodically exchanges information with the display device 50 via the wired data transfer line 21. If the information exchange is confirmed for a certain period of time or more, It is only necessary to determine that the wired image transfer line 22 has been connected.

FIG. 5 is a block diagram for explaining the display device 50 in detail. The display device 50 includes the connector 5 described above.
1. Wired communication device 52 for transmitting and receiving information via wired connection path 20, wireless communication device 53 for transmitting and receiving information via wireless connection path 30, graphics adapter 54 for generating an image, graphics adapter 54 Frame memory 5 for expanding the image generated by
5. Display panel 56 for outputting an image to a user, input device 5 for receiving an input operation from the user
7 and a detachment detecting device 58 for detecting a connection state with the wired connection path 20.

The display device 50 receives an image or a drawing from the arithmetic processing unit 10 via the connector 51 and the wired communication device 52 from the wired connection path 20 or via the wireless communication device 53 from the wireless connection path 30. It receives primitives and sends them to graphics adapter 54. The graphics adapter 54 generates a complete image on the frame memory 55. The generated image is displayed on the display panel 56.

The input device 57 receives an input from a user using the display device 50 and transmits the input to the arithmetic processing device 1 through the wired data transfer line 21 or the wireless connection path 30.
Sent to 0. Examples of the input device 57 include a touch panel, a switch, a trackball, a trackpoint,
Examples include a microphone, a camera, and a fingerprint collator. The attachment / detachment detection device 58 is similar to the attachment / detachment detection device 42 of the cradle 40 described above.
0 is electrically detected. As a method of detecting attachment / detachment, a method using a mechanical switch, a method of monitoring a signal flowing through the connector 51, and detecting a change in the signal level are conceivable.

Next, the operation of the system according to the present embodiment will be described. FIG. 6 is a flowchart illustrating the operation of switching the connection mode in the arithmetic processing device 10. Here, the switching operation between the wired connection mode and the wireless connection mode is shown. C of the arithmetic processing unit 10
The PU 11 obtains a signal from the attachment / detachment detection device 42 of the cradle 40 through the wired data transfer line 21 (Step 10).
1) It is determined whether or not the attachment / detachment state of the display device 50 has changed (step 102). If the attachment / detachment state does not change, the process returns to step 101. If the detached state has changed, the detached state after the change is checked (step 103). If it is in the mounted state, the mode is shifted to the wired connection mode (step 104), and the process returns to step 101. If it is in the detached (leaving) state, the mode transits to the wireless connection mode (step 105), and
Return to

Here, the attachment / detachment detection device 4 for the cradle 40
As a method for detecting the attachment / detachment state of the display device 2 by the
Several methods are conceivable. For example, there is a method of monitoring the wired image transfer line 22 and electrically detecting a change in the signal level due to the connection of the end of the signal line, thereby determining the mounted state. Further, for example, there is a method of providing a mechanical switch on the cradle 40 and detecting that the display device 50 is physically mounted on the cradle 40. Further, for example, there is a method in which information is periodically exchanged with the display device 50 via the wired data transfer line 21, and when the information exchange is confirmed for a predetermined time or more, it is determined that the connection is established. is there.

FIG. 7 is a flowchart for explaining the transition of the arithmetic processing unit 10 to the wired connection mode. When it is determined that the wired image transfer line 22 is connected, the arithmetic processing device 10 transitions to the wired connection mode. First, the CPU 11 acquires information on the display device 50 via the wired data transfer line 21 (step 111). The information acquired here is the display resolution of the display device 50, the maximum screen update frequency, and the like. Using the obtained information, the arithmetic processing device 10 is initialized for the wired connection mode, such as the initialization of the graphics adapter 13 by the CPU 11 (step 112). This makes it possible to transmit image data at a resolution and a transfer rate that are convenient for the display device 50. The arithmetic processing device 10 starts sending image data through the wired image transfer line 22 (step 113).

Next, the CPU 11 sends information for wireless connection and information for authentication to the display device 50 via the wired data transfer line 21 (step 114). CPU
11 waits for the arrival of an authentication request from the display device 50 via the wireless communication device 16 (step 115).
When the authentication request is received, the display device 50 is authenticated based on the authentication request (step 116), and prepares for transition to the wireless connection mode. As described above, in the normal wireless communication, when performing wireless communication, exchange of information for wireless connection is performed via the wireless connection path 30. In the present embodiment, wireless communication is performed. It is characterized in that the exchange of information for authentication and the information for authentication are executed in advance using the wired connection path 20. In other words, in the present embodiment, both the wired connection and the wireless connection are provided, and information required for the wireless connection at the time of the wired connection is displayed in advance on the display device 50.
Is being transferred to the Internet. And at the time of wired connection,
Authentication required for wireless connection can be completed.

FIGS. 8A to 8C show data necessary for wireless connection and authentication, and transmission and reception thereof. In step 1 shown in FIG. 8A, information necessary for wireless connection transmitted from the arithmetic processing unit 10 to the display device 50 via the wired data transfer line 21 of the wired connection path 20 is shown.
Assuming that information necessary for wireless connection is IEEE 802.11 and TCP / IP as wireless connection protocols, the basic specification of IEEE 802.11, ESSI
D (Extended Service Set Identity), WEP (Wired Equivalent Privac) to check for errors and tampering
As shown in y), there is information necessary for connection of the radio link layer. Also, such as an IP address (IP address), a gateway address (Gateway address), and a netmask (Netmask) used when dividing the IP address,
Information required for network layer connection, or DHCP (Dynamic Host Configurator) for acquiring them
Information Protocol). Further, a host address (Host add) which is an identifier of the host (the processing unit 10) is used.
ress).

In step 1 shown in FIG. 8A,
The information required for the wireless connection can be transmitted not only unconditionally to the display device 50 but also under predetermined conditions. For example, a unique ID for each display device 50 to which connection should be permitted in advance is calculated by the arithmetic processing device 1.
The information can be registered in the address 0, check the unique ID of the display device 50 at the time of wired connection, and send necessary information at the time of wireless connection only when the connection is permitted.

In step 2 shown in FIG. 8B, information necessary for authentication for permitting access to information at the time of wireless connection is transmitted via the wired data transfer line 21. Information necessary for this authentication includes the public key of the arithmetic processing device 10, a session ID, and the like. In step 3 shown in FIG. 8C, a wireless connection is made from the display device 50 to the arithmetic processing device 10, and an authentication request is transmitted from the display device 50 to the arithmetic processing device 10.

In the display device 50, the wireless interface is initialized based on the information sent in step 1 shown in FIG. Thereafter, the session ID transmitted in step 2 shown in FIG. 8B is encrypted with the public key of the arithmetic processing unit 10 and wirelessly transferred via the wireless connection path 30. However, the encryption is not essential, and another encryption method may be used. Note that the transmission of the authentication request through the wireless connection can be executed regardless of whether the display device 50 is connected to the wired connection path 20. If all of the authentication work can be completed before the display device 50 is detached from the cradle 40, it is excellent in that the transition to wireless communication can be performed promptly.

FIG. 9 is a flowchart showing the processing in the arithmetic processing unit 10 when transitioning to the wireless connection mode. The CPU 11 in the arithmetic processing device 10 shifts to the wireless connection mode when the attachment / detachment detection device 42 of the cradle 40 determines that the display device 50 has been separated from the cradle 40. CPU1 in wireless connection mode
First, transmission of image data through the wired image transfer line 22 is stopped (step 121). Next, transmission of image data is started via the wireless connection path 30 (step 1).
22). Here, the display device 50 has already been authenticated,
Communication via the wireless connection path 30 is immediately possible. That is, in the present embodiment, even in the transition from the wired connection to the wireless connection, the user does not need to perform an explicit mode change operation, and the display device 50 as the wireless connection terminal is simply connected to the cable (cradle 40). By simply disconnecting from the connection mode, the connection mode can be changed immediately.

FIG. 10 is a flowchart showing a transfer mode switching process in the wireless connection mode performed by the arithmetic processing unit 10. In the wireless connection mode, the image data is transferred to the arithmetic processing unit 1 via the wireless connection path 30.
It is sent from 0 to the display device 50. The data transferred is
The transfer method is switched according to the display contents, and efficient transfer is performed. In switching the transfer method in the wireless connection mode, the CPU 11 first waits for a predetermined time (step 131), monitors the data size on the communication path, and determines whether the data size exceeds a set value (step 131). 132). The reason for waiting for a predetermined time in step 131 is to perform smoothing (averaging) in consideration of the fact that screen information may temporarily change.

This step 132 is to judge how much data has been sent within a certain period of time. In step 132, the data size does not exceed the predetermined set value, and If it is smaller, the mode transits to the transfer mode using the drawing primitive (step 13).
3). On the other hand, if the data size exceeds the predetermined set value, the mode is changed to a mode in which the image is accumulated and the changed area is transferred as the image (step 13).
4). That is, in the present embodiment, as a transfer method, in addition to a drawing primitive-based drawing instruction protocol, a drawing image is integrated in a screen buffer on the host, and a screen snapshot is taken at an appropriate timing by the terminal (display device 50).
Function to transfer to

In step 132, the amount of data size on the communication path is used as an index (feature) for switching the transfer method, but the index is dynamically switched using other indices (feature). It is possible. For example, there are the following alternatives. -The amount of drawing data when the "drawing primitive" protocol is used. More precisely, the ratio of the size of the sequence in the rendering primitives to the amount of screen image generated by their rendering process.・ Effective network bandwidth ・ Drawing performance of display device 50 ・ Change in data size on communication path

FIG. 11 is a flow chart showing the processing of the mode for transferring as an image in the wireless connection mode shown in step 134 of FIG. After receiving the drawing command (step 141), the CPU 11 of the arithmetic processing unit 10 performs drawing on the frame memory 14 via the graphics adapter 13 (step 142).
Thereafter, the CPU 11 determines whether to transmit a screen image (step 143). As an index to be determined, for example, whether or not the amount of change in the data on the screen exceeds a set value can be used as a criterion. Also, whether or not a set number or more of drawing commands have been processed, whether or not a time longer than a set time since the last screen image transmission has elapsed, and whether or not a transmission request from the display device 50 has been received. Can be determined. For example, if any one or more of these conditions are satisfied, the CPU
11 calculates the changed area and calculates the area to be transmitted (step 144). Then, after reading the corresponding image from the frame memory 14, the read image is encoded (step 145). Thereafter, the encoded image is sent to the wireless communication device 16,
Sent to the display device 50 via the wireless connection path 30
(Step 146), the process ends. If it is determined in step 143 that the image should not be transmitted, the process ends.

FIG. 12 is a flowchart showing the transfer mode processing using the drawing primitive shown in step 133 of FIG. CPU 1 of arithmetic processing unit 10
After receiving the drawing command (step 151), the drawing 1 draws on the frame memory 14 via the graphics adapter 13 (step 152). Next, the CPU 11 converts the received drawing command into a drawing primitive, and further encodes it (step 153). The encoded drawing primitive is sent to the wireless communication device 16 and sent to the display device 50 via the wireless connection path 30 (step 15).
4), the process ends.

As described above, according to the present embodiment, depending on the data size on the communication path, whether to send the image data as a drawing primitive or to transfer the changed area as an image image,
Is switching. In other words, in the transfer mode using the drawing primitive, when the value exceeds the predetermined set value in step 132, the mode is changed to a mode in which the image is transferred as an image. With this configuration, for example, when a changed area is transferred as an image, useless transfer such as painting the same area twice with the same color can be prevented, and the reaction time (Latency If) is sacrificed, for example, the data size on the wireless connection path 30 can be adjusted by delaying the transfer interval by accumulating the changing part in the arithmetic processing device 10.

Next, processing in the display device 50 as a wireless connection terminal will be described. FIG. 13 shows the display device 50.
6 is a flowchart related to connection mode switching performed by the user. When switching the connection mode, the display device 50
First, a signal for the attachment / detachment state is obtained by the attachment / detachment detection device 58 (step 201). Then, it is determined whether or not the attachment / detachment state has changed (step 202). If not, the process returns to step 201 and the detachment detection device 58
Wait for a signal from If the state of attachment / detachment has changed, the state of attachment / detachment is determined (step 203). When the display device 50 is connected to the cradle 40 via the connector 51 and the connector 41 and the wired connection path 20 is in the connected state, the mode is changed to the wired connection mode (step 204). It transits to a mode (Step 205), and returns to Step 201, respectively.

FIG. 14 is a flowchart for explaining the transition to the wired connection mode shown in step 204 of FIG. Upon transition to the wired connection mode, the display device 50 is initialized for the wired connection mode (step 211). This includes initialization of the wired communication device 52 and the graphics adapter 54. Thus, the image data sent from the arithmetic processing unit 10 is displayed on the display panel 56. Next, display of image data is started through the wired image transfer line 22 of the wired connection path 20 (step 212), and information for the wireless connection mode is displayed.
(Wireless connection information) and authentication information are received (step 21
3). The information received here is as described in FIG. Further, the display device 50 initializes the wireless communication device 53 (step 214), and is logically connected to the arithmetic processing device 10 via the wireless connection path 30. Finally, the display device 50 sends an authentication request to the arithmetic processing device 10 via the wireless connection path 30 (Step 215).

As described above, in the present embodiment, after receiving the information for the wireless connection mode and the authentication information via the wired connection path 20, the operation of sending the authentication request via the wireless connection path 30 is performed. Has been realized. With such a configuration, generally complicated and dangerous settings for wireless connection can be automatically performed, and smooth switching between wired connection and wireless connection is enabled. by this,
Even a user without specialized knowledge can use a wireless connection terminal (display device 50).
Etc.) can be easily used.

In the wired connection mode, the display device 50
Receives image data via the wired image transfer line 22. The received image data is sent to the graphics adapter 54 via the wired communication device 52. The graphics adapter 54 expands the received image data on the frame memory 55. Further, the graphics adapter 54 periodically reads the contents of the frame memory 55 and displays the contents on the display panel 56. Thus, at the time of the wired connection, it is possible to obtain the same functions and the like as those of the conventional display device.

FIG. 15 is a diagram for explaining the transition to the wireless connection mode shown in step 205 of FIG. The display device 50, which is a wireless connection terminal, first stops receiving and displaying the image data transmitted via the wired image transfer line 22 (Step 221). Thereafter, display of the image data sent via the wireless connection path 30 is started (step 222).

In the wireless connection mode, the wireless communication device 53 of the display device 50 receives the image data or the drawing primitive sent from the arithmetic processing unit 10 via the wireless connection path 30. The received data is sent to the graphics adapter 54. The graphics adapter 54 develops a final image on the frame memory 55 based on the transmitted data. Then, the graphics adapter 54 periodically reads the contents developed in the frame memory 55 and displays the contents on the display panel 56. Thus, the display operation in the wireless connection mode is performed.

As described in detail above, in the present embodiment, the display device 50, which is a wireless connection terminal, has both the communication path of the wired connection path 20 and the communication path of the wireless connection path 30, and switches between them for use. I have. As a result, at the time of a wired connection, it has the same function, performance, and operability as a conventional display device, and specifically, the number of colors that can be displayed, the screen update speed, and the like are equivalent to those of the conventional wired display device Is possible. Furthermore, it can be used immediately by simply connecting with a cable without setting on the display device 50 side.

Further, in the present embodiment, in the wired connection mode, the cable connecting between the host (the processing unit 10) and the terminal (the display device 50) is a one-to-one connection, and a secure communication path ( Control line). Also, attention is paid to the point that the wireless link of the wired connection path 20 and the wireless link of the wireless connection path 30, which are wired connection cables, are not exclusive and can be used simultaneously. On this premise, information for wireless connection is transmitted in advance from the arithmetic processing device 10 on the host side to the display device 50 on the terminal at the time of wired connection, and necessary authentication work is also completed in advance. Thus, it is not necessary to perform setting work on the display device 50 side in advance for the operation at the time of wireless connection. Also, in the transition from the wired connection to the wireless connection, the user does not need to explicitly change the mode, and the connection mode is changed immediately by simply disconnecting the display device 50 from the cable (or the cradle 40). It can be performed.

Further, two types of display data transfer methods using the wireless connection path 30 are provided: a drawing primitive-based drawing instruction protocol and a protocol for transmitting an image image as snapshot image difference information of a screen image. It is possible to dynamically switch between the two depending on a certain feature amount of the screen display data. by this,
In wireless connection, which has a lower transfer capability than in wired connection, practically sufficient display performance can be ensured.

[0064]

As described above, according to the present invention, in a system having a wired connection path and a wireless connection path with a terminal, it is possible to smoothly switch between a wired connection and a wireless connection.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a schematic configuration of a system according to an embodiment.

FIG. 2 is a block diagram illustrating an overall configuration of a system according to the present embodiment.

FIG. 3 is a block diagram further illustrating a system configuration according to the present embodiment;

FIG. 4 is a block diagram illustrating a cradle according to the present embodiment.

FIG. 5 is a block diagram for describing a display device in the present embodiment in detail.

FIG. 6 is a flowchart showing a connection mode switching operation in the arithmetic processing unit.

FIG. 7 is a flowchart illustrating a transition to a wired connection mode in the arithmetic processing device.

FIGS. 8A to 8C are diagrams showing data necessary for wireless connection and authentication, and transmission / reception thereof.

FIG. 9 is a flowchart showing a process in the arithmetic processing device when transitioning to a wireless connection mode.

FIG. 10 is a flowchart illustrating a transfer method switching process in a wireless connection mode performed by the arithmetic processing device.

FIG. 11 is a flowchart showing processing in a mode for transferring an image in a wireless connection mode.

FIG. 12 is a flowchart showing processing in a transfer mode using a drawing primitive.

FIG. 13 is a flowchart related to connection mode switching performed by the display device.

FIG. 14 is a flowchart illustrating a transition to a wired connection mode.

FIG. 15 is a diagram for explaining a transition to a wireless connection mode.

[Explanation of symbols]

Reference Signs List 10 arithmetic processing device (host), 11 CPU, 12 main memory, 13 graphics adapter, 14 frame memory, 15 wired communication device, 16 wireless communication device, 2
0: Wired connection path, 21: Wired data transfer line, 22: Wired image transfer line, 30: Wireless connection path, 40: Cradle, 41: Connector, 42: Detachment detection device, 50: Display device, 51: Connector, 52 ... wired communication device, 53 ... wireless communication device, 54 ... graphics adapter, 55 ... frame memory, 56 ... display panel, 57 ... input device, 5
8 ... Removal detection device

Continuing from the front page (72) Inventor Takao Moriyama 1623-14 Shimotsuruma, Yamato-shi, Kanagawa Prefecture Within the Tokyo Research Laboratory, IBM Japan, Ltd. (72) Inventor Katsura Kawase 1623-14 Shimotsuruma, Yamato-shi, Kanagawa Prefecture F-term (reference) in the Tokyo Research Laboratory, IBM Japan, Ltd. 5B069 AA01 BA04 BB16 LA03 LA05 5C082 AA01 BA02 BA12 BB01 CB01 DA87 MM09 5K067 BB21 DD27 DD52 EE02 FF02 FF23

Claims (26)

[Claims] 1. A system comprising: a terminal; and an arithmetic processing device that performs communication between the terminal and the terminal via a wired connection path and a wireless connection path, wherein the arithmetic processing device includes the wired connection path. Wire communication means for performing communication with the terminal via the wireless communication path, and information required for communication with the terminal via the wireless connection path via the wireless connection path to the terminal using the wire communication means. And a transmission means for performing the transmission. 2. The information processing apparatus according to claim 1, wherein the transmitting unit transmits information necessary for authentication for permitting the terminal to access the information using the wireless connection path.
The described system. 3. An attaching / detaching unit for attaching / detaching the terminal, provided directly or indirectly to the arithmetic processing unit, wherein the terminal is attached / detached to / from the attaching / detaching unit. Detecting means for detecting that, based on a detection result by the detecting means, switching means for switching between communication via the wired connection path and communication via the wireless connection path, further comprising: The system of claim 1, wherein: 4. A system comprising: a display device; and an arithmetic processing device that performs communication between the display device and the display device via a wireless connection path, wherein the arithmetic processing device includes: A first transfer unit that transfers data to the display device using a primitive-based drawing instruction protocol; and a second transfer device that transfers data to the display device using a protocol that sends an image as difference information of a snapshot of a screen image. And a switching means for switching between the first transfer means and the second transfer means based on a predetermined characteristic amount. 5. The apparatus according to claim 4, wherein the predetermined characteristic amount is at least one of a data size on a communication path, a change amount, an effective bandwidth of a network, and a drawing performance of the display device. The described system. 6. The second transfer means, after receiving a drawing command, determines whether to transmit the screen image based on a predetermined index, and when it is determined that the screen image should be transmitted, 5. The system according to claim 4, wherein the image based on the calculated area to be transmitted is transmitted. 7. The method according to claim 6, wherein the predetermined index is set after the image image is transmitted last when a changed amount of the screen image exceeds a set value, when a predetermined number or more of drawing instructions are processed. 7. The system according to claim 6, wherein at least one of the following is the case where the specified time has elapsed and the case where a transmission request has been received from the display device. 8. An arithmetic processing device that has a wired connection mode that is communication via a wired connection path and a wireless connection mode that is communication via a wireless connection path, and performs communication with a terminal. Wired communication means for communicating with the terminal via a connection path, wireless communication means for performing wireless communication with the terminal via the wireless connection path, and before communication with the terminal by the wireless communication means Sending means for sending information required at the time of communication via the wireless connection path to the terminal using the wired communication means,
An arithmetic processing device comprising: 9. A determining means for determining whether or not the terminal has departed from the wired connection path, and, when it is determined that the terminal has been departed from the wired connection path, via the wireless connection path based on the wireless communication means. 9. The arithmetic processing device according to claim 8, further comprising: switching means for switching to the wireless communication. 10. A CPU, a graphics adapter for generating image data based on a drawing command, a frame memory for expanding image data generated by the graphics adapter, and a display device according to a transfer mode using a drawing primitive And a wireless communication device that transmits data for drawing to the CPU, wherein the CPU determines whether or not to transmit an image based on a predetermined index, and calculates an area to be transmitted. Reading the image from the frame memory, and transmitting the read image data to the display device via a wireless connection path in place of the transfer mode using the drawing primitive. An arithmetic processing device characterized by the above-mentioned. 11. The apparatus according to claim 1, wherein the CPU calculates an area to be transmitted based on a change in data in the image developed in the frame memory.
0. The arithmetic processing unit according to 0. 12. The predetermined index is set after the last transmission of the image image, when the changed amount of the screen image exceeds a set value, when a predetermined number or more of drawing instructions are processed, At least one of the following cases: when the elapsed time elapses, and when a transmission request from the display device is received.
The arithmetic processing device according to claim 10, wherein: 13. A wireless connection terminal that communicates with an arithmetic processing device via a wired connection path and a wireless connection path, wherein the wired communication means communicates with the arithmetic processing device via the wired connection path; Wireless communication means for communicating with the arithmetic processing device via the wireless connection path, the wired communication means prior to communication via the wireless connection path, when communicating via the wireless connection path A wireless connection terminal receiving required information via the wired connection path. 14. The wireless connection terminal according to claim 13, wherein the wired communication unit receives information required for authentication at the time of communication via the wireless connection path via the wired connection path. 15. The wireless communication unit according to claim 14, wherein the wireless communication unit wirelessly transfers an authentication request based on the information necessary for the authentication received by the wired communication unit to the arithmetic processing unit. Wireless connection terminal. 16. A detecting means for detecting whether or not the wired connection path has been disconnected, based on the detection by the detecting means, stopping data communication by the wired communication means, and 14. The wireless connection terminal according to claim 13, wherein communication is performed by means. 17. An image processing apparatus further comprising: developing means for developing an image in a frame memory based on data received via the wireless connection path; and display means for reading and displaying the image developed in the frame memory. The wireless connection terminal according to claim 13, wherein: 18. A data transfer method for performing communication between an arithmetic processing unit and a terminal via a wired path and a wireless path, the method comprising: determining whether the terminal is connected to the wired path; When the terminal is connected to the wired path, information required for wireless connection in communication via the wireless path is transferred in advance via the wired path. 19. The data transfer method according to claim 18, wherein when the terminal is connected to the wired path, authentication required for the wireless connection is performed. 20. A session ID is transferred from the processing unit to the terminal via the wired path, and the session ID is transferred from the terminal to the processing unit via the wireless path. 20. The data transfer method according to claim 19, wherein: 21. A data transfer method for performing communication between a display device and an arithmetic processing device via a wireless path, comprising: detecting a predetermined characteristic amount in communication via the wireless path; A first transfer method for performing transfer to the display device by a drawing primitive-based drawing instruction protocol including a screen drawing command based on the feature amount;
A data transfer method characterized by switching between a second transfer method for transferring data to a display device according to a protocol for transmitting an image image as difference information of a snapshot of a screen image. 22. A computer having a function of determining whether or not a terminal is connected to a wired path, and a function required for wireless connection in communication via a wireless path when the terminal is connected to the wired path. And a function of transferring information to be transmitted via the wired path in advance. 23. The computer according to claim 22, further comprising a function of executing authentication required for the wireless connection when the terminal is connected to the wired path. The program described. 24. A computer comprising: a function of detecting a predetermined characteristic amount in communication via a wireless path; and a display primitive based on a detected primitive, a drawing primitive-based drawing instruction protocol including a screen drawing command. A function of switching between a first transfer method for transferring data to the display device and a second transfer method for transferring data to the display device by a protocol for transmitting an image image as snapshot image difference information. Program to let you. 25. A storage medium storing a program to be executed by a computer in a manner readable by the computer, the program comprising: a process of determining whether or not a terminal is connected to a wired path; A process of transferring information required for wireless connection in communication via a wireless route via the wired route in advance when the terminal is connected to the wired route; And causing the computer to execute processing related to authentication required for the wireless connection. 26. A storage medium storing a program to be executed by a computer in a manner readable by the computer, the program comprising: processing for detecting a predetermined characteristic amount in communication via a wireless path; A first transfer method for transferring to a display device based on a feature amount based on a drawing primitive-based drawing instruction protocol including a screen drawing command, and a protocol for transmitting an image image as difference information of a snapshot of a screen image. A process for switching between a second transfer method for transferring data to a display device and a second transfer method.