Computer having removable input/output device

A computer is disclosed that includes a switching part configured to detect connection of an external computer to the computer upon the connection, and to determine, in response to the detection of the connection of the external computer, that the output signal of the external computer be received and output to the output part of the computer.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a highly portable computer reduced in size, weight, and power consumption with a minimum decrease in performance and the system of the computer, and more particularly to a computer that has a removable input/output device with a processor and enables the main-body computer to be remotely controlled via data communications using the input/output device.

2. Description of the Related Art

Primary output devices such as the liquid crystal monitor of a notebook computer and primary input devices such as keyboards and touch pads are fixed to a computer main body and are usually not separable or removable therefrom. That is, these primary input devices and output devices cannot be connected to other computers and used as an input/output device.

As described above, the input device and the output device are not separable from the computer main body, which results in the following inconveniences. First, the entire computer, that is, the CPU, hard disk, etc., of the computer main body that consume large amounts of power are necessary in order to operate the computer main body. This yields low performance with respect to power consumption in the case of operating the computer with a battery where the computer is carried about. Further, the CPU of the computer main body, its heat sink, and the hard disk of the computer main body, which are necessary to operate the computer main body, are heavy. This yields low performance with respect to weight. Further, the CPU of the computer main body, its heat sink, and the hard disk of the computer main body necessary to operate the computer main body are voluminous. This yields low performance with respect to volume. Further, the entire computer is always necessary at the time of use in order to operate the computer main body. Therefore, the entire computer is likely to be stolen particularly in the case of a notebook computer, which is very likely to result in leakage (disclosure) of hard disk data. Further, principal components such as a CPU and a hard disk are closely connected to other components of the computer. Therefore, in order to replace such principal components, it is necessary to take the computer main body apart, which is a very difficult operation.

Further, neither an input device nor an output device in the conventional desktop computer has a processor that autonomously operates. Therefore, even if it is desired that the input or output device be separated from the computer, the input or output device has no function of directly or remotely operating the computer main body.

Regarding the desktop computer, it is often the case that its external devices such as an image display unit such as a liquid crystal display; and input devices such as a keyboard, a touch pad, a mouse, and a trackball are sufficiently usable in terms of function while its internal processor or storage unit has become obsolete with the passage of time. Accordingly, in this case, it is possible to replace only the main body of the desktop computer while continuing to use the image display unit and the input devices.

In the case of the conventional notebook computer, however, if its internal processor or storage unit has become obsolete with the passage of time, the entire notebook computer is no longer usable although its image display unit such as a liquid crystal display and its input devices such as a keyboard, a touch pad, a mouse, and a trackball are often sufficiently operable in terms of function.

Further, in the case of using a notebook computer at an outside location and using a desktop computer back at a base location (for example, an office), an image display unit and an input device are separately required for the desktop computer although the notebook computer has an image display unit and an input device. It is possible for the notebook computer to virtually display an image of the external computer (desktop computer) or make input to the external computer by logging on the desktop computer using a network logon function. However, settings required for this, such as software preparation and settings, and network settings, are complicated. Further, since the connection is established through a network, the connection depends on the condition of the network to be unstable, thus causing a delay in screen display or input operation.

Japanese Laid-Open Patent Application No. 2002-189516 discloses a process control computer system that remotely starts and stops another computer. Japanese Laid-Open Patent Application No. 2002-312068 discloses a notebook personal computer that carries two liquid crystal screens at the same time. This personal computer displays the screen of the computer on an external liquid crystal display unit. Japanese Laid-Open Patent Application No. 2004-246634 discloses an information processing apparatus and an information storage device for the information processing apparatus, that is, discloses a computer removable from a display unit. This technique is for reducing the size and weight of a computer main body. Japanese Laid-Open Patent Application No. 5-94250 discloses a computer in which part of an input device is removable. Japanese Laid-Open Patent Application No. 10-97440 discloses a computer diagnostic apparatus that enables recovery of a primary computer by transmitting the self-diagnosis results of the primary computer to a separable secondary computer and analyzing the self-diagnosis results. Japanese Laid-Open Patent Application No. 11-259003 discloses a space-saving information processor including a computer having a housing as wide as a display unit. Japanese Laid-Open Patent Application No. 2000-89855 discloses an electronic apparatus and a function expansion unit that expands functions of the electronic apparatus by having the electronic apparatus connected thereto. Japanese Utility Model Registration No. 3064588 discloses a connection structure of a signal line of the liquid crystal display of a notebook personal computer for facilitating connection and separation of the signal line of the liquid crystal display and a motherboard. Further, Japanese Patent No. 3283853 discloses a docking station including a function expansion unit that expands functions of an electronic apparatus by having the electronic apparatus connected thereto.

SUMMARY OF THE INVENTION

Embodiments of the present invention may solve or reduce one or more of the above-described problems.

According to one embodiment of the present invention, there is provided a computer in which one or more of the above-described problems may be solved or reduced.

According to one aspect of the present invention, the performance of a computer with respect to power consumption, weight, volume, security, and remote operation at the time of its operation is improved, and the performance of the computer with respect to partial replaceability at the time of failure is improved.

According to one embodiment of the present invention, there is provided a computer including a switching part configured to detect a connection of an external computer to the computer upon the connection, and to determine, in response to the detection of the connection of the external computer, that an output signal of the external computer be received and output to an output part of the computer.

According to one embodiment of the present invention, there is provided a computer, wherein a connection of an external computer to the computer is detected upon the connection, and it is determined, in response to the detection of the connection of the external computer, that a signal input through an input part of the computer be input to the external computer.

According to one embodiment of the present invention, there is provided a computer including a switching part configured to detect a connection of an external computer to the computer upon the connection; and to determine, in response to the detection of the connection of the external computer, that an output signal of the external computer be received and output to an output part of the computer, and a signal input through an input part of the computer be input to the external computer.

According to one embodiment of the present invention, there is provided a computer including a main body and an input/output part including an input part and an output part, wherein the input/output part is removably provided on the main body.

According to one embodiment of the present invention, there is provided a computer including a main body and an input/output part including an input part and an output part, the input/output part being removably provided on the main body, wherein the input/output part includes a processor including a peripheral device controller, the processor having a processing function as a computer, the processor being configured to be remotely connectable to the main body through data communications.

According to one aspect of the present invention, it is possible to improve the performance of a computer with respect to power consumption, weight, volume, security, and remote operation at the time of its operation. Further, it is also possible to improve the performance of the computer with respect to partial replaceability at the time of failure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A description is given, with reference to the accompanying drawings, of embodiments of the present invention.

FIGS. 1 and 2are perspective views (partially exploded views) of a computer1integrated with an input/output device according to a first embodiment of the present invention. Mainly, a notebook computer is assumed as the computer1according to the first embodiment. However, the computer1may be a desktop computer of a space-saving type, which is a desktop computer integrated with an input/output device.

The computer1includes a switching unit6that can output the contents of the output of another computer26(FIG. 2) to an output device2of the computer1. Further, the switching unit6can also input the contents of input to an input device4of the computer1to the computer26.

When the computer1is not connected to the computer26as shown inFIG. 1, a switch signal18to the switching unit6is “H (high).” At this point, the switching unit6provides an input signal8from the input device4to a processor A12in the computer1as an input signal A10. Receiving the input signal A10, the processor A12outputs an output signal A14to the switching unit6. Receiving the output signal A14, the switching unit6provides the output signal A14to the output device2as an output signal16.

In the case of connecting the computer26to the computer1, the computer26and the connection between the computer1and the computer26are configured so that the switch signal18to the switching unit6is “L (low)” as shown inFIG. 2. At this point, the switching unit6provides the input signal8from the input device4to a processor B24in the computer26as an input signal B20. Receiving the input signal B20, the processor B24outputs an output signal B22to the switching unit6. Receiving the output signal B22, the switching unit6provides the output signal B22to the output device2as the output signal16.

For example, it is assumed that a notebook personal computer (computer1) is used at an outside location and a desktop personal computer (computer26) is used back at a base location (for example, home, office, etc.). In this case, the desktop personal computer needs a monitor as an output device and a keyboard and a mouse as input devices. However, by connecting the computer26(desktop personal computer) to the computer1(notebook personal computer), it is possible to display the output signal of the computer26(desktop personal computer) on the output device2(for example, a monitor) of the computer1(notebook personal computer), and it is possible to make input to the computer26(desktop personal computer) using the input device4(for example, a keyboard and/or a touch pad) of the computer1(notebook personal computer). That is, the computer26(desktop personal computer) can dispense with a monitor, a keyboard, and a mouse, so that it is possible to reduce cost and save space.

FIGS. 3 and 4are perspective views (partially exploded views) of a computer including a removable input/output device31and a computer main body56according to a second embodiment of the present invention. As shown inFIGS. 3 and 4, the computer according to this embodiment may be a notebook computer having a removable input/output device (for example, a flat panel monitor, a keyboard, and a touch pad/track ball). The input/output device31does not have secondary storage, and includes a secondary processor A42of low power consumption. However, the secondary processor42includes a CPU and a memory part so as to be able to perform the minimum required processing.

The removable input/output device31according to the second embodiment includes a switching unit36that can output the contents of the output of the computer main body56to an output device (display and output device)32of the input/output device31. Further, the switching unit36can also input the contents of input to an input device34of the input/output device31to the computer main body56.

In the case of attaching the removable input/output device31to the computer main body56, the computer main body56and the connection between the removable input/output device31and the computer main body56are configured so that a switch signal48to the switching unit36is “L (low)” as shown inFIG. 3. At this point, the switching unit36provides an input signal38from the input device34to a primary processor B54in the computer main body56as an input signal B50. Receiving the input signal B50, the primary processor B54outputs an output signal B52to the switching unit36. Receiving the output signal B52, the switching unit36provides the output signal B52to the output device32as an output signal46.

When the input/output device31is not connected to the computer main body56as shown inFIG. 4, the switch signal48sent to the switching unit36is “H (high).” At this point, the switching unit36provides the input signal38from the input device34to the secondary processor A42in the removable input/output device31as an input signal A40. Receiving the input signal A40, the secondary processor A42outputs an output signal A44to the switching unit36. Receiving the output signal A44, the switching unit36provides the output signal A44to the output device32as the output signal46.

It is assumed that normally, the removable input/output device31and the computer main body56according to the second embodiment are integrated and used as a unit. However, the removable input/output device31and the computer main body56may also be used independent of each other. Since the removable input/output device31includes the secondary processor A42, the removable input/output device31can also operate as a simple computer (such as a FDA) when separated or detached from the computer main body56.

Further, as shown inFIG. 5, the removable input/output device31detached from the computer main body56is attached to another computer (computer main body56A) to serve as the input/output device of the other computer. The computer main body56according to this embodiment has a so-called “docking station” shape, and the computer main body56and the removable input/output device31are connected with the connector of the docking station. The switching unit36of the removable input/output device31recognizes connection of the connector, and performs switching between the input/output signal of the primary processor B54of the computer main body56and the input/output signal of the secondary processor A42of the removable input/output device31.

In the second embodiment, since the input/output device31is detachable, the input/output device31is also usable in another computer (personal computer) according to this embodiment as shown inFIG. 5. For example, even if the output device32such as a monitor is broken, it is only necessary to replace the removable input/output device31. Therefore, it is possible to save time and effort for moving data and reinstalling software in the computer main body56. Accordingly, it is possible to reduce time for which the computer is unusable.

Further, the detachable input/output device31with the secondary processor A42is reduced in weight and size compared with the case where the detachable input/output device31is integrated with the computer main body56. The secondary processor A42can be lower in power consumption than the primary processor B54, so that the detachable input/output device31is reduced in power consumption compared with the case where the detachable input/output device31is integrated with the computer main body56. Even if only the removable input/output device31is dropped and broken while being carried, this breakage has nothing to do with the computer main body56. As a result, it is possible to protect data inside a hard disk. Further, since it is possible to fix the computer main body56to furniture with a hook or chain, adequate measures can be taken against theft. Since the removable input/output device31retains hardly any data, there is little possibility of information outflow (disclosure) even if the removable input/output device31is stolen.

FIGS. 3 and 4are also perspective views (partially exploded views) of a computer including the removable input/output device31and the computer main body56according to a third embodiment of the present invention. As set forth below, the third embodiment relates in particular to the switching operation of the switching unit36in the removable input/output device31.

As shown inFIGS. 3 and 4, the computer main body56including the primary processor B54is in the form of a so-called docking station, and the removable input/output device31is in the form of a notebook personal computer. The computer main body56and the removable input/output device31may be connected with, for example, a cable with connection connectors.

The switching unit36provided in the removable input/output device31includes an input switching part36aand an output switching part36b, and performs switching between the input/output signal to/from the primary processor B54and the input/output signal to/from the secondary processor A42. (SeeFIG. 6.) First, when the removable input/output device31is attached to the computer main body56, the switch signal48is “L” so as to enable the input signal B50to and the output signal B52from the primary processor B54. Here, the input signal A40contains information on the switch signal48, which is input to an interrupt operation unit82(FIG. 6) of the secondary processor A42so as to control stoppage and returning to operation of the secondary processor A42.

Next, when the removable input/output device31is detached from the computer main body56, the switch signal48is “H” so as to enable the input signal A40to and the output signal A44from the secondary processor A42. Here, the input signal B50contains information on the switch signal48, which is input to an interrupt operation unit102(FIG. 6) of the primary processor B54so as to control stoppage and returning to operation of the primary processor B54.

As shown inFIG. 6, when the removable input/output device31is detached, the input to the interrupt operation unit82of the secondary processor A42becomes “H,” and the returning operation of the secondary processor A42is started. The details of this returning operation are described in the flowchart of (a) ofFIG. 7. That is, when the removable input/output device31is detached in step S02, in step S04, it is determined whether the removable input/output device31is stopped. Then, if necessary, a returning operation is performed in step S08. Thereafter, in step S10, the input/output is switched to the secondary processor A42.

On the other hand, when the removable input/output device31is attached, the input to the interrupt operation unit82of the secondary processor a42becomes “L,” and the operation of the secondary processor A42is stopped. (SeeFIG. 6.) The details of this stopping operation are described in the flowchart of (a) ofFIG. 8. That is, after attachment of the removable input/output device31in step S62, in step S64, the input/output is switched to the primary processor B54.

Meanwhile, as shown inFIG. 6, when the removable input/output device31is detached, the input to the interrupt operation unit102of the primary processor B54becomes “H,” and the operation of the primary processor B54is stopped. The details of this stopping operation are described in the flowchart of (b) ofFIG. 7. That is, after the removable input/output device31is detached in step S32, in step S34, it is determined whether to perform an automatic stopping operation. If it is determined that the automatic stopping operation is to be performed (YES in step S34), in step S36, a stopping operation is performed.

Further, when the removable input/output device31is attached, the input to the interrupt operation unit102of the primary processor B54becomes “L,” and the returning operation of the primary processor B54is started. (SeeFIG. 6.) The details of this returning operation are described in the flowchart of (b) ofFIG. 8. That is, after the removable input/output device31is attached in step S80, in step S82, it is determined whether the computer main body56is stopped. If it is determined in step S82that the computer main body56is stopped, in step S84, its returning operation is performed.

As described above, since the secondary processor A42is provided in the removable input/output device31, the removable input/output device31can operate as an independent computer by switching the input/output to the secondary processor A42in the case of detaching the removable input/output device31. At this point, the primary processor B54(of the computer main body56) can also operate as a computer independent of the removable input/output device31.

Further, it is possible to cause transition of the computer main body56and the removable input/output device31to a virtually detached state by opening a detachment switch106of the computer main body56or a detachment switch104of the removable input/output device31.

Referring toFIG. 6, the secondary processor A42includes a CPU70, a memory/virtual secondary storage unit72, a display processing unit74, the secondary storage unit76, an input processing unit78, the data communications unit80, and the interrupt processing unit82. The input signal A40is input from the input switching part36ato the input processing unit78. The output signal A44is output from the display processing unit74to the output switching part36b. The primary processor B54includes a CPU90, the data communications unit92, a display processing unit94, the secondary storage unit96, an input processing unit98, a memory/virtual secondary storage unit100, and the interrupt processing unit102. The output signal B52is output from the display processing unit94to the output switching part36b. The input signal B50is input from the input switching part36ato the input processing unit98.

FIG. 9is a perspective view (partially exploded view) of a computer including the removable input/output device31and the computer main body56according to a fourth embodiment of the present invention. The fourth embodiment is substantially the same as the second and third embodiments, but is different therefrom in that the removable input/output device31and the computer main body56are remotely connected. At least two ways are assumable to switch between the input/outputs of the primary processor B54and the secondary processor A42by remote connection. A description is given below, focusing mainly on the difference therebetween.

(a) Connection Via a Network

A remote network service function via a network, such as the “remote desktop connection” of “Windows XP Professional (Microsoft)” is enabled in the computer main body56. The primary processor B54processes the service, and the secondary processor A42performs remote connection. The output information of the primary processor B54is transmitted to the secondary processor A42via a data transmission line58, and the secondary processor A42displays the information on the output device32. The secondary processor A42transmits information from the input device34to the primary processor B54via the data transmission line58, and the primary processor B54processes the information as input from the input device34. This makes it possible for the removable input/output device31in a detached state to virtually operate as the input/output device of the computer main body56.

When the removable input/output device31is detached and there is no remote connection therefrom, the computer main body56may enter a low power consumption mode such as suspend/hibernation/shutdown and be prevented from operating. In such a case, enabling a remote start command receiving function such as Wake On LAN (WOL) in the computer main body56makes it possible to cause the computer main body56to return from the low power consumption mode by transmitting a remote start command such as Magic Packet™ at the time of performing remote connection from the secondary processor A42of the removable input/output device31. Further, transmission of a message from the primary processor B54of the returned computer main body56to the secondary processor A42via the data transmission line58makes it possible to remotely connect the secondary processor A42immediately after the return of the primary processor B54.

In the case of detaching the secondary processor A42from the computer main body56and remotely connecting the detached secondary processor A42in the above-described form of connection according to the fourth embodiment, causing an auxiliary device of the secondary processor A42to be recognized as, for example, a network directory or shared folder by the computer main body56makes it possible to view the auxiliary device of the secondary processor A42from the computer main body56on its basic software. As a result, a document created while the detached removable input/output device31is operating as a PDA can be edited from the computer main body56at the time of remote connection.

Further, in the case of detaching the secondary processor A42from the computer main body56and remotely connecting the detached secondary processor A42, causing an auxiliary device of the primary processor B54to be recognized as, for example, a network directory or shared folder by the secondary processor A42makes it possible to view the auxiliary device of the primary processor B54from the secondary processor A42on its basic software. As a result, a document created in advance in the detached computer main body56can be edited from the removable input/output device31at the time of remote connection.

Further, in the case of physically attaching the secondary processor A42to the computer main body56, causing an auxiliary device of the secondary processor A42to be recognized as, for example, a USB memory by the computer main body56, the auxiliary device of the secondary processor A42can be viewed from the computer main body56on its basic software. As a result, a document created while the detached removable input/output device31is operating as a PDA can be edited from the computer main body56when the removable input/output device31is attached to the computer main body56.

(b) Connection Using a Radio Peripheral Device

With the computer main body56recognizing the removable input/output device31as being directly connected thereto physically, the computer main body56and the detached removable input/output device31are connected by radio connection such as infrared, Bluetooth or an IEEE 802.11 ad hoc connection. As a result, the removable input/output device31can operate as a directly connected device.

Connecting the removable input/output device31and the computer main body56as described above makes it possible to connect the computer main body56to an AC power supply. Accordingly, the computer main body56can operate with its maximum processing power. Accordingly, unlike in the case of battery connection, there is no need to consider operable time or power consumption. The secondary processor A42of the removable input/output device31performs regular processing (that is, processing of the output information of the primary processor B54and transmission of input information to the primary processor B54) irrespective of the operating state of the primary processor B54. Accordingly, its power consumption is substantially constant. Therefore, it can be expected of the removable input/output device31to operate for a pre-assumed operable time irrespective of the status of processing of the computer main body56.

(c) Processing Under the Above-Described Connection (a) or (b)

In order to realize the above-described connection (a) or (b) in the fourth embodiment of the present invention, at least it is necessary for the computer main body56and the removable input/output device31to operate as independent computers. Further, the secondary processor A42and the primary processor B54are provided with data communications units80and92(FIG. 6), respectively, for data communications.

Further, as shown inFIG. 9, with a remote connection from the secondary processor A42to the primary processor B54being established, the primary processor B54transmits output information to the secondary processor A42, and the secondary processor A42transmits input information to the primary processor B54. Thereby, the output information of the primary processor B54is output to the output device32, and the input information from the secondary processor A42is input to the primary processor B54.

Next, an overview is given, with reference toFIGS. 7 and 8, of the operations of the removable input/output device31and the computer main body56at the time when the removable input/output device31and the computer main body56are detached (and remotely connected) and at the time when the removable input/output device31and the computer main body56are attached. At the time of remote connection, the secondary processor A42transmits a remote start command to the primary processor B54via the data transmission line58(step S14of (a) ofFIG. 7and step S38of (b) ofFIG. 7), and the primary processor B54returns from a state such as a suspended state (step S40of (b) ofFIG. 7). When the primary processor B54returns in response to the remote start command, the primary processor B54notifies the secondary processor A42of its return (step S42of (b) ofFIG. 7and step S16of (a) ofFIG. 7).

Further, when the removable input/output device31is detached and remotely connected, the input to the interrupt operation unit82of the secondary processor A42becomes “H” (FIG. 6), so that a remote connecting operation is started (steps S12, S14, S16, S18, S20, S22, S24, S26, and S28of (a) ofFIG. 7). That is, in step S12, it is determined whether to perform automatic remote connection. If YES in step S12, in step S14, the secondary processor A42transmits a remote start command to the primary processor B54via the data transmission line58as described above. Then in step S16, it is determined whether a waiting period has passed or whether a return notice (indicating the return to operation of the computer main body56) is received from the computer main body56. If the waiting period has passed or a return notice is received (YES in step S16), in step S18, the removable input/output device31is remotely connected to the computer main body56. Then, in step S20, it is determined whether the removable input/output device31has been successfully connected remotely to the computer main body56. If YES in step S20, in, step S22, a secondary storage unit sharing remote connecting operation (described below) is performed. Then, in step S24, the detaching operation ends. If NO in step S20, in step S26, it is determined whether to retry connection. If NO in step S26, in step S28, the detaching operation ends.

When the removable input/output device31is attached, the input to the interrupt operation unit82of the secondary processor A42becomes “L” (FIG. 6), and a remote connection disconnecting operation is started (steps S66, S68, S70, S72, S74, and S76of (a) ofFIG. 8). That is, in step S66, it is determined whether the removable input/output device31is being remotely connected to the computer main body56. If YES in step S66, in step568, it is determined whether a secondary storage unit76(FIG. 6) of the secondary processor A42is shared. If YES in step S68, in step S70, it is determined whether the sharing connection of the secondary storage unit76is disconnected. If YES in step S70, then in step S72, the sharing connection of a secondary storage unit96(FIG. 6) of the primary processor B54is disconnected. Then, in step S74, the remote connection is disconnected, and in step S76, the attaching operation ends. The corresponding operation in the computer main body56is as shown in steps S86, S88, S90, S92, S94, and S96of (b) ofFIG. 8.

Further, when the removable input/output device31is attached, the input to the interrupt operation unit102of the primary processor B54becomes “L” (FIG. 6), and the operation of recognizing the secondary storage unit76of the secondary processor A42is started. When the removable input/output device31is detached and remotely connected (steps S44and S46of (b) ofFIG. 7), the input to the interrupt operation unit102of the primary processor B54becomes “H” (FIG. 6), and the operation of recognizing the secondary storage unit76of the secondary processor A42is started (step S48of (b) ofFIG. 7).

When the removable input/output device31is detached and remotely connected (steps S18and S20of (a) ofFIG. 7), the input to the interrupt operation unit82of the secondary processor A42becomes “H” (FIG. 6), and the operation of recognizing the secondary storage unit96of the primary processor B54is started (step S22of (a) ofFIG. 7).

FIG. 10is a perspective view (partially exploded view) of a computer201according to a fifth embodiment of the present invention. The computer201may be a notebook computer. In the following embodiments, computers corresponding to the computer201are also referred to by the same reference numeral201.FIG. 11is a perspective view (partially exploded view) of a conventional notebook computer1201to be compared with the computer201.

The conventional notebook computer1201(FIG. 11) has an image output switching unit1206provided therein. In response to a switch signal A218, the image output switching unit1206selects-outputting an image input signal A208to an image output device202of the main body as an image output signal A216or outputting the image input signal A208to an external image output device212via an interface and a connector as an image output signal B210.

On the other hand, in the computer201according to the fifth embodiment, an image input signal B214can be input to the interface of an image input/output switching unit206, which interface connects to the external image output device212. Further, input/output switching of the interface can be performed by a switch signal B220.

In the case of displaying an image of the computer201on the external image output device212, the interface of the image input/output switching unit206, which interface connects to the external image output device212, is switched to “output mode” by the switch signal B220, and the image input signal A208is output to the external image output device212as the image output signal B210by operating the switch signal A218.

In the case of displaying an image of an external computer222on the image output device202of the main body of the computer201, the interface of the image input/output switching unit206, which interface connects to the external computer222, is switched to “input mode” by the switch signal B220, and the image input signal B214is output to the image output device202of the main body of the computer201as the image output signal A216by operating the switch signal A218. When the interface is in “input mode,” the image input signal B214may be automatically output to the image output device202of the main body of the computer201as the image output signal A216by the switch signal220.

FIG. 12is a perspective view (partially exploded view) of the computer201according to a sixth embodiment of the present invention. The computer201of this embodiment has the function of inputting the output of an input device204of the main body of the computer201to the external computer222.

The computer201includes the image input/output switching unit (input device output switching and image input/output switching unit)206to which an input device input224of the main body is connected, and outputting an input device output A226to the main body or outputting an input device output B228to the external computer222can be selected by the switch signal B220in the image input/output switching unit206.

In the case of operating the computer201, the input device input224is output as the input device output A226to be input to the input device controller of the main body by operating the switch signal B220. In the case of operating the external computer222, the input device input224is output as the input device output B228to be input to the input device controller of the external computer222by operating the switch signal B220.

A seventh embodiment of the present invention relates to an interface and a computer formed by assigning an input device input signal used in an external computer to a signal already assigned to an external image output interface in a computer such as a notebook personal computer.FIG. 13is an assignment list of terminals and signals assigned to a VGA connector, which is a conventional interface, showing a conventional VGA (VESA DDC) terminal layout.

On the other hand,FIG. 14is a list showing a VGA (VESA DDC) terminal layout according to the seventh embodiment, in which the input device signals of PS/2 DATA and PS/2 CLK are assigned to DDC-SDA of Terminal12and DDC-SCL of Terminal15, respectively.

In this case, the input device input224of the computer201can be connected to the external computer222. When the external image output device212is connected to the computer201, it is possible to display an image itself from the computer201on the external image output device212. However, since it is not possible to use SDA and SCL signals, data cannot be transmitted with a DDC interface.

An eighth embodiment of the present invention relates to an interface and a computer formed by assigning one of an input device input signal used in an external computer and a DDC interface by switching to a signal assigned as unused or reserved in an external image output interface in a computer such as a notebook personal computer.FIG. 15is a list showing a VGA (VESA DDC) terminal layout according to the eighth embodiment.

Referring toFIG. 15, the input device signals of PS/2 DATA and PS/2 CLK are assigned to a reserved signal of Terminal4and an ID0 signal of Terminal11, which is normally not used, respectively, and SDA and SCL of a DDC interface are assigned to the reserved signal of Terminal4and the ID0 signal of Terminal11, respectively.

In this case, when the computer201is used as an image display unit of the external computer222, first, Terminal4and Terminal15are assigned as DDC interfaces, so that the external computer222obtains information on the image display unit of the computer201. Thereafter, Terminal4and Terminal11are assigned as PS/2 DATA and PS/2 CLK, respectively. As a result, the input device input of the computer201can be connected to the external computer222.

In this case, the input device input of the computer201can be connected to the external computer222, and data can be transmitted with a DDC interface. It is possible for the computer201to display an image on the external image output device212when the computer201is connected thereto. However, in the case of connecting the external computer222to the computer201, it is necessary for the computer201to suitably switch the DDC interface and the PS/2 interface. Therefore, the structure of the image input/output switching unit206provided in the computer201is rather complicated.

A ninth embodiment of the present invention relates to an interface and a computer formed by assigning an input device input signal used in an external computer to a signal assigned as unused or reserved in an external image output interface in a computer such as a notebook personal computer.FIG. 16is a list showing a VGA (VESA DDC) terminal layout according to the ninth embodiment.

Referring toFIG. 16, the input device signals of PS/2 DATA and PS/2 CLK are assigned to the reserved signal of Terminal4and the ID0 signal of Terminal11, which is normally not used, respectively. In this case, it is possible to connect the input device input of the computer201to the external computer222.

Further, in this case, the input device input of the computer201can be connected to the external computer222, and data can be transmitted with a DDC interface. When the computer201and the external image output device212are connected, it is possible for the computer201to have an image displayed on the external image output device212while maintaining compatibility with the conventional terminal layout.

FIG. 17is a perspective view (partially exploded view) of the computer201according to a tenth embodiment of the present invention. In the computer201according to the tenth embodiment, an input signal that detects connection of the external computer222is assigned to an external image output interface, and the signal is connected to the switch signal B220of the image input/output switching unit206. Thereby, input and output of the image input/output switching unit206are automatically switched.

First, in the computer201according to the tenth embodiment, an input signal that detects connection of the external computer222is assigned to a terminal of the external image output interface. Further, as shown inFIG. 17, this input signal is connected to the switch signal B220of the image input/output switching unit206, and has a pull-up resistor added thereto. Further, a corresponding terminal in the external computer222is grounded.

In the computer201according to the tenth embodiment, when the external computer222is connected to the external image output interface, the switch signal B220switches from “H” to “L.” As a result, the input/output interface of the image input/output switching unit206automatically switches to “input mode.”

Then, the image input signal B214of the external computer222is displayed on the image output device of the computer201via the image output signal A216, while the input device input224is output as the input device output B228.

Further, in the computer201according to the tenth embodiment, when the external computer222is not connected to the external image output interface, the switch signal B220switches from “L” to “H.” As a result, the input/output interface of the image input/output switching unit206automatically switches to “output mode.”

Then, the image input signal A208of the computer201is displayed on the external image output device212via the image output signal B210, while the input device input224is output as the input device output A226.

FIGS. 18 and 19are perspective views (partially exploded views) of the computer201according to an 11thembodiment of the present invention. The 11thembodiment is almost the same as the tenth embodiment. Therefore, a description is given below, focusing mainly on the difference therebetween.

In the computer201according to the 11thembodiment, a change switch230is provided to the switch signal B220of the image input/output switching unit206. As a result, input and output of the image input/output switching unit206can be manually switched.

In the configuration shown inFIG. 18, the computer201has the change switch230added to the switch signal B220of the image input/output switching unit206. When the change switch230is switched ON, the state of the switch signal B220changes from “H” to “L.” At this point, the input/output interface of the image input/output switching unit206switches to “input mode,” so that the image input signal B214of the external computer222is displayed on the image output device202of the computer201via the image output signal A216.

When the change switch230is switched OFF, the switch signal B220becomes “H.” At this point, by combining operation of the switch signal A218, it is also possible to display the image input signal A208on the image output device202of the computer201via the image output signal A216without putting the input/output interface of the image input/output switching unit206in the state of outputting.

On the other hand, in the configuration shown inFIG. 19, the computer201has an input signal that detects connection of the external computer222assigned to a terminal of the external image output interface. This signal is connected to the switch signal B220of the image input/output switching unit206, and has a pull-up resistor and the change switch230added thereto on the way to the switch signal B220. A corresponding terminal of the external computer222is grounded. When the external computer222is connected to the external image output interface of the computer201, the switch signal B220changes from “H” to “L” if the change switch230is ON. At this point, the input/output interface of the image input/output switching unit206switches to “input mode,” so that the image input signal B214of the external computer222is displayed on the image output device202of the computer201via the image output signal A216.

If the change switch230is switched OFF in this state, the switch signal B220changes to “H.” At this point, by combining operation of the switch signal A218, it is also possible to display the image input signal A208on the image output device202of the computer201via the image output signal A216without putting the input/output interface of the image input/output switching unit206in the state of outputting.

The change switch230shown inFIG. 19may be disposed outside the computer201. For example, the change switch230may be disposed on the interface between the computer201and the external computer222or on the external computer222.

FIG. 20is a perspective view (partially exploded view) of the computer201according to a 12thembodiment of the present invention. According to the 12thembodiment, an input signal that detects connection of an external computer is assigned to a signal already assigned to an external image output interface in a computer such as a notebook personal computer, and the signal is connected to a switch signal of an image input/output switching unit, thereby changing input and output of the image input/output switching unit.

In the computer201shown inFIG. 20, an input signal that detects connection of the external computer222is assigned to +5 VDC of Terminal9of the conventional external image output interface. This signal is connected to the switch signal B220of the image input/output switching unit206, and at the same time, a pull-up resistor to 5 V power supply is added to the signal. A corresponding terminal of the external computer222is grounded.

In this case, in response to connecting the external computer222to the external image output interface of the computer201, the switch signal B220changes from “H” to “L.” As a result, the input/output interface of the image input/output switching unit206switches to “input mode,” so that the image input signal B214of the external computer222is displayed on the image output device202of the computer201via the image output signal A216.

FIG. 21is a list showing a VGA (VESA DDC) terminal layout according to the 12thembodiment. As shown inFIGS. 20 and 21, a pull-up resistor to 5 V power supply is added to +5 VDC of Terminal No. 9, which is 5 V output, and +5 VDC is connected to the switch signal B220of the image input/output switching unit206. As a result, when the external image output is connected, 5 V is output. Accordingly, it is possible to achieve expansion while maintaining compatibility with the existing image output interface.

According to a 13thembodiment of the present invention, an input signal that detects connection of an external computer is assigned to a signal assigned as unused or reserved in an external image output interface in a computer such as a notebook personal computer, and the signal is connected to a switch signal of an image input/output switching unit, thereby switching input and output of the image input/output switching unit. A perspective view (partially exploded view) of a computer according to the 13thembodiment is substantially the same asFIG. 20.

FIG. 22is a list showing a VGA (VESA DDC) terminal layout according to the 13thembodiment. In the computer201(FIG. 20) according to the 13thembodiment, an input signal that detects connection of the external computer222is assigned to the reserved terminal of Terminal4of the conventional external image output interface. This signal is connected to the switch signal B220of the image input/output switching unit206, and has a pull-up resistor added thereto. A corresponding terminal of the external computer222is grounded.

In this case, by connecting the external computer222to the external image output interface of the computer201, the switch signal B220changes from “H” to “L.” As a result, the input/output interface of the image input/output switching unit206switches to “input mode,” so that the image input signal B214of the external computer222is displayed on the image output device202of the computer201via the image output signal A216.

According to the 13thembodiment, by adding a pull-up resistor to Terminal4, which is a reserved terminal, and connecting Terminal4to the switch signal B220of the image input/output switching unit206, it is possible to achieve expansion while maintaining compatibility with the existing external image output interface.

A 14thembodiment of the present invention relates to, for example, terminals and a connector forming an external image output interface in a computer.FIG. 23Ais a schematic diagram showing connectors each having a conventional detection terminal.FIGS. 23B and 24Athrough24C are schematic diagrams showing a connector having detection terminals in a computer and a connector having detection terminals on the external computer side according to the 14thembodiment of the present invention. According to the 14thembodiment, by employing multiple detection terminals that are different in length, the state of a signal or bus that performs data transmission is changed using the difference between detection terminals in the time required before contacting.

First,FIG. 23Ais a schematic diagram showing connectors each having a conventional detection terminal. In the male connector, the detection terminal is shorter than the signal terminal so that the signal terminals come into contact with each other first at the time of insertion. As a result, the contact of the signal terminals is more stable by the time the detection terminals come into contact with each other. In the case of outputting a signal in each of the male connector (on the right) and the female connector (on the left) in this structure, the collision of signals may occur to destroy data and degrade, damage, or destroy an apparatus when the signal terminals come into contact with each other. Further, since the detection terminal and the signal terminal of the female connector have the same length, the detection terminals come into contact with each other within a short period of time after the signal terminals come into contact with each other.

According to the 14thembodiment, each of the male and female connectors has multiple detection terminals different in length from each other as shown inFIG. 23B. The female connector has a female detection terminal A272, a female signal terminal274, and a female detection terminal B276. The female detection terminal A272is longer than the female signal terminal274. The female detection terminal B276is shorter than the female signal terminal274. The male connector has a male detection terminal A282, a male signal terminal284, and a male detection terminal B286. The male detection terminal A282is longer than the male signal terminal284. The male detection terminal B286is shorter than the male signal terminal284. The time between the contact of the detection terminals A272and282and the contact of the signal terminals274and284is longer than conventionally, and the time between the contact of the signal terminals274and284and the contact of the detection terminals B276and286is also longer than conventionally.

In this case, it is assumed that when the connectors are not connected, a signal on the female connector side is output, and a signal on the male connector side is not output. Further, it is assumed that when the connectors are connected, a signal on the female connector side is in input mode, and a signal on the male connector side is output.

As shown inFIG. 24A, when connection of the connectors is started and the detection terminals A272and282come into contact with each other, an input/output switch signal on the female connector side is controlled to be switched to input mode. When the connection of the connectors is continued, the signal terminals274and284come into contact with each other after the detection terminals A272and282come into contact with each other as shown inFIG. 24B. At this point, since the female signal terminal274is shorter than the conventional female signal terminal, a longer period of time is required before the contact of the signal terminals274and284. Therefore, the contact of the signal terminals274and284is made with more allowance of time for switching from output mode to input mode and state transition due to the contact of the detection terminals A272and283.

When the connection of the connectors is further continued, the detection terminals B276and286come into contact with each other after the signal terminals274and284come into contact with each other as shown inFIG. 24C. An output control terminal on the male connector side is controlled by the contact of the detection terminals B276and286, so that a signal is output to the signal terminal284. At this point, since the detection female terminal B276is shorter than the female signal terminal274and the female detection terminal A272, a longer period of time is required before the female detection terminal B276comes into contact with the male detection terminal B286. Accordingly, the contact of the detection terminals B276and286is made with more allowance of time for switching from output mode to input mode and state transition due to the contact of the detection terminals A272and283, and further for stabilizing the contact of the signal terminals274and284.

FIG. 25is a perspective view (partially exploded view) of the computer201according to a 15thembodiment of the present invention.FIG. 26is a block diagram showing the computer201according to the 15thembodiment. In the computer201according to the 15thembodiment, using the multiple detection terminals different in length according to the 14thembodiment, the input/output of the image signal of the computer201and the output of the external computer222are controlled based on time difference. Further, the output to the external image output device212and the input of the external computer222are switched depending on the connection.

In the computer201according to the 15thembodiment, an input signal that detects connection of the external computer222and a signal232that controls the image output control terminal of the external computer222are assigned to terminals of the conventional external image output interface. The former signal is connected to the switch signal A218of the image input/output switching unit206of the computer201, and has a pull-up resistor added thereto. A corresponding terminal on the external computer222side is grounded. On the other hand, the latter signal232is connected to the image output control terminal of an image signal output unit222a(FIG. 26) of the external computer222with a pull-up resistor being added thereto (in the external computer222). A corresponding terminal on the computer201side is grounded.

The image input/output switching unit206outputs the image output signal B210when the state of the input switch signal A218is “H,” and stops outputting the image output signal B210to be in the state of inputting when the state of the input switch signal A218is “L.” The image signal output unit222aprovided in the external computer222stops outputting the image input signal B214when the input switch signal A218is “H,” and outputs the image input signal B214when the input switch signal A218is “L.”

As shown inFIG. 26, when the female connector on the computer201side and the male connector on the external computer222side are not connected, the switch signal A218is “H,” and the image input signal A208of the computer201is output as the image output signal B210via the image input/output switching unit206to be displayed on the external image output device (external monitor)212. When connection of the connectors is started, first, the detection terminals A272and282come into contact with each other, so that the switch signal A218changes from “H” to “L.” As a result, the image input/output switching unit206stops outputting the image output signal B210; so that the image signal terminal274is in the state of inputting. When the connection of the connectors is continued, the image signal terminals274and284come into contact with each other. When the connection of the connectors is further continued, the detection terminals B276and286come into contact with each other, so that the image input signal B214is output from the image signal output unit222aof the external computer222, and is displayed on the image output device (main body monitor)202of the computer201via the image signal terminals274and284.

FIG. 27is a flowchart showing these transitions. In step S102, insertion of the external computer222is started with the computer201outputting the image output signal B210and the external computer222not outputting the image input signal B214. Then, in step S104, it is determined whether the detection terminals A272and282have come into contact with each other. If YES in step S104, in step S106, the switch signal A218changes from “H” to “L.” As a result, the image input/output switching unit206stops outputting the image output signal B210so as to wait for input of the image input signal B214, which is not yet output from the external computer222. Then, in step S108, the image signal terminal284on the external computer222side comes into contact with the female image signal terminal274. Then, in step S110, it is determined whether the detection terminals B276and286have come into contact with each other. If YES in step S110, in step S112, the state of a switch signal input B234changes from “H” to “L,” so that the image input signal B214is output from the external computer222to be input to the computer201and displayed on the image output device (main body monitor)202of the computer201via the image signal terminals274and284.

FIG. 28is a list showing a VGA (VESA DDC) terminal layout according to the 15thembodiment of the present invention. In the computer201according to the 15thembodiment, an input signal that detects connection of the external computer222and the signal232that controls the image output control terminal of the external computer222are assigned to signals assigned as unused or reserved in the conventional external image output interface. As a result, it is possible to achieve expansion while maintaining compatibility with the existing external image output interface.

FIG. 29Ais a schematic front view of an image signal male connector244in a computer according to a 16thembodiment of the present invention. The 16thembodiment of the present invention focuses particularly on the connector part of the image output interface described above in the 14thand 15thembodiments.

In the 16thembodiment, as shown inFIG. 29A, the connector244has a projection240added thereto in order to prevent improper insertion. The projection240prevents the image signal male connector244according to the 16thembodiment from being connected physically to a conventional image signal female connector (FIG. 30B). This prevents improper insertion. Further, this allows the image signal male connector244according to the 16thembodiment to be connected to only an image signal female connector246having a hook hole242for receiving the projection240(FIG. 30A).

On the other handsFIG. 29Bis a schematic front view of a conventional image signal male connector. This male connector does not have a projection for preventing improper insertion. Accordingly, the conventional image signal male connector shown inFIG. 29Bis connectable to either the conventional image signal female connector (FIG. 30B) or the image signal female connector246having the hook hole242for receiving the projection240(FIG. 30A).

FIG. 30Ais a schematic front view of the image signal female connector246in a computer according to a 17thembodiment of the present invention. The 17thembodiment of the present invention also focuses particularly on the connector part of the image output interface described above in the 14thand 15thembodiments.

As shown inFIG. 30A, the image signal female connector246according to the 17thembodiment of the present invention has the hook hole242for receiving the projection240shown in the 16thembodiment. This hook hole242allows the image signal male connector244according to the 16thembodiment to be connected to the image signal female connector246according to the 17thembodiment.

On the other hand,FIG. 30Bis a schematic front view of the conventional image signal female connector. This female connector does not have a hook hole for receiving the projection240of the image signal male connector244according to the 16thembodiment. Accordingly, the conventional image signal female connector ofFIG. 30Bcan be connected to only the conventional image signal male connector (FIG. 29B), and cannot be connected to the image signal male connector244having the projection240according to the 16thembodiment of the present invention.

FIG. 31is a block diagram showing the computer201and the external computer222in the case of using the image signal female connector246in the computer201and the image signal male connector244on the external computer222side according to an 18thembodiment of the present invention. The computer201and the external computer222are connected through the image signal female connector246according to the above-described 17thembodiment and the image signal male connector244according to the above-described 16thembodiment. Accordingly, the image signal female connector246has detection terminals and the hook hole242for preventing improper insertion. The hook hole242may also serve as a detection terminal. Likewise, the image signal male connector244has terminals and the projection240for preventing improper insertion. The projection240may also serve as a detection terminal.

As shown inFIG. 31, the projection240is added to the male connector244and the hook hole242is added to the female connector246at the external image output interface in order to prevent improper insertion. An input signal that detects connection of the external computer222is assigned to the detection terminals formed thereby. Further, these detection terminals are connected to the switch signal A218input of the image input/output switching unit206of the computer201with a pull-up resistor being added thereto. A corresponding terminal on the external computer222side is grounded.

The image input/output switching unit206outputs the image output signal B210when the switch signal A218is “H,” and stops outputting the image output signal B214to be in the state of inputting when the switch signal A218is “L.” Accordingly, when the connectors244and246are not connected, the switch signal A218is “H,” so that the image output signal B210is output via the image input/output switching unit206of the computer201to be displayed on the external image output device (external monitor)212.

When the connectors244and246are connected, the projection240and the hook hole242come in contact with each other so that the switch signal A218changes from “H” to “L.” As a result, the image input/output switching unit206stops outputting the image output signal B210, so that the image signal terminal is in the state of inputting. At this point, the image input signal B214output from the external computer222is input to the image signal terminal of the computer201to be displayed on the image output device202of the computer201.

FIG. 32is a diagram showing connection of the image signal female connector246according to the 18thembodiment or a conventional image signal female connector246′ and the image signal male connector244according to the 18thembodiment or a conventional image signal male connector244′.

The conventional image signal male connector244′ is connectable to the image signal female connector246with the hook hole242and to the conventional image signal female connector246′.

The male connector244with the projection240cannot be connected to the conventional image signal female connector246′ as indicated by broken arrow Q inFIG. 32. As a result, the conventional computer cannot receive an image signal of the external computer222according to one embodiment of the present invention. On the other hand, the male connector244with the projection240is connectable to the female connector246with the hook hole242.

As a result, it is possible to maintain compatibility in the connection to the conventional external monitor, and it is also possible to prevent the external computer222according to one embodiment of the present intention from being connected to the conventional computer to cause malfunction.

FIG. 33is a schematic front view of the image signal female connector246in the computer201and the image signal male connector244on the external computer222side according to a 19thembodiment of the present invention. The image signal female connector246is a female VGA connector having an extension for an external PC (computer) connection detection (recognition signal) and input device signals. The image signal male connector244is a male VGA connector having an extension for the external PC (computer) connection detection (recognition signal) and the input device signals. In the image signal female connector246and the image signal male connector244inFIG. 33, signal assignment is the same as the existing one (246′ and244′) in principle, and connectors246α and244α are added as extensions to the image signal female connector246and the image signal male connector244, respectively, for the connection detection (recognition) signal and the input device signals.

In the case of connecting an external monitor having the existing image signal male connector244′ to the image signal female connector246of the computer201inFIG. 33, it is possible to display an image of the computer201on the external monitor via the existing compatible part (246′) of the image signal female connector246.

In the case of connecting the external computer222according to this embodiment, not only the existing compatible part of each of the image signal connectors244and246but also the added connectors244α and246α are used. As a result, the computer201and the external computer222according to this embodiment can properly exchange signals. That is, since the connected detection signal operates the input device output switching and image input/output switching unit206of the computer201, it is possible to input a signal of the input device of the computer201to the external computer222, so that it is possible to display an image of the external computer222on the image output device202of the computer201.

FIG. 34is a schematic front view of the image signal female connector246in the computer201and the image signal male connector244on the external computer222side according to a 20thembodiment of the present invention. The 20thembodiment is a specific example of the 19thembodiment. As is clear from the description of the 19thembodiment, each of the connectors244and246integrates an extension connector for the connection detection (recognition) signal and the input device signals and the existing image signal connector, so that in the case of using the external computer222, it is possible to support its connection with a single connector on each of the computer201side and the external computer222side.

FIG. 35is a list showing a VGA (VESA DDC) terminal layout in the computer201according to the 20thembodiment of the present invention. According to the list ofFIG. 35, the input device signals of PS/2 DATA and PS/2 CLK are assigned to extension terminals E3and E4, respectively, and the external PC image signal enabling signal and the external PC connection recognition signal are assigned to extension terminals E1and E2, respectively. Regarding the image signal, the VGA terminal layout remains the same as the existing one.

In the case of connecting an external monitor having the existing image signal connector in the 20thembodiment, since the image signal connector is the same as the conventional one, it is possible for the computer201to display an image on the external monitor while maintaining compatibility with the conventional terminal layout. Further, in the case of connecting the external computer222according to the present invention, extension connectors having terminals regarding the connection detection (recognition) signal and the input device signals of extension and the image signal. At this point, it is possible to input a signal of the input device of the computer201to the external computer222, and since the detection signal of the extension connector parts operates the input device output switching and image input/output switching unit206of the computer201, it is possible to display an image of the external computer222on the image output device202of the computer201.

FIG. 36is a perspective view (partially exploded view) of the computer201according to a 21stembodiment of the present invention. According to the 21stembodiment of the present invention, it is possible to use a built-in device of the computer201and an external peripheral device connected to the computer201from the external computer222connected to the computer201. By way of example, those using a USB interface as an interface for outputting the input device signal of the computer201to the external computer222and those integrating a USB concentrator (hub) with the image input/output switching unit (input/output device output switching unit)206are assumed.

In the case where the external computer222is not connected, the switch signal B220is not activated, so that the input device input224is output to the input device output A226of the computer201. At this point, an internal device250and an external peripheral device252connected to the concentrator (206) may be connected to the input device output A226.

When the external computer222is connected, the switch signal B220is activated, so that the input device input224is output to the input device output B228of the computer201so as to be input to the external computer222. At this point, the internal device250and the external peripheral device252connected to the concentrator (206) are connected to the input device output B228. As a result, not only the input device204of the computer201but also the internal device250and the external peripheral device252are usable in the external computer222. At this point, it may be determined, using another switch signal, whether to cause the internal device250and the external peripheral device252connected to the concentrator (206) to be connected to the input device output B228.

FIG. 37is a block diagram showing the connectors244,246,244′ and246′ in the computer201, a conventional external computer222′, and an external computer relay device260according to a 22ndembodiment of the present invention. According to the 22ndembodiment, in the case of connecting the conventional external computer222′ to the computer201, the relay device260is disposed therebetween.

It is clear from the above description that the computer201according to the present invention is assumed to be connected to the external computer222according to the present invention. Accordingly, it is assumed that a predetermined operation may not be performed in the case of connecting the conventional external computer222′ to the computer201according to the present invention. The relay device260is provided in order to solve this problem.

The relay device260includes a relay unit262that controls output of an image signal input from the external computer222′. The relay unit262outputs the image signal of the external computer222′ to the computer201side if the state of a switch signal input B having a pull-up resistor added thereto is “L,” and does not output the image signal of the external computer222′ if the state of the switch signal input B is “H.” Further, a signal to be connected to a switch signal input A having a pull-up resistor added thereto when the relay device260is connected to the computer201is grounded in the relay device260.

The relay device260can separate an input device signal assigned from the computer201to the image signal interface, and direct the separated input device signal to a conventional input device interface (246″and244″). Further, the relay device260uses the connector244having the improper insertion prevention projection240for preventing connection to computers other than the computer201according to the present invention. That is, by connecting the conventional external computer222′ to the relay device260and connecting the relay device260to the computer201according to the present invention, the conventional external computer222′ can be equivalent to the external computer222according to the present invention.

Further, a change switch (not graphically illustrated) that performs connection and disconnection may be provided to the switch signal input A and the switch signal input B of the relay device260so that the output of the image output device of the computer201main body can be switched by manually operating the change switch on the relay device260.

A 23rdembodiment of the present invention relates to image signal interface connectors that integrate the features of the fifth, sixth, ninth, tenth, 12th, 14th, 15th, 16th, 17th, and 18thembodiments.FIG. 38is a schematic front view of the image signal female connector246in the computer201and the image signal male connector244on the external computer222side according to the 23rdembodiment of the present invention.FIG. 39is a list showing a VGA (VESA DDC) terminal layout according to the 23rdembodiment.

According to the 23rdembodiment, the +5 VDC terminals of the image signal connectors244and246are assigned as detection terminals that have a +5 V pull-up resistor and detect connection of the external computer222. When the connectors244and246are connected, the detection terminals come into contact with each other before all the other terminals come into contact. Therefore, first, the switch signal A218that controls the input/output of the image input/output switching unit206of the computer201changes from “H” to “L.” As a result, the image signal output to the external image output device (external monitor)212is stopped, so that the image input/output switching unit206can switch to “input mode.”

Since the image signal connector244and the image signal connector246have the projection240and the hook hole242for preventing improper insertion, respectively, the external monitor212having the conventional image signal male connector is connectable to the computer201, but the external computer222cannot be connected to a computer such as a notebook computer having the conventional image signal female connector.

Further, the projection240and the hook hole242for preventing improper insertion are shorter than other terminals and assigned as detection terminals that detect connection of the external computer222at the time of connection of the connectors244and246. That is, these detection terminals come into contact with each other after all the other terminals come into contact. As a result, the state of a switch signal B that controls the output of the external computer222changes from “H” to “L,” so that an image signal of the external computer222is input to the computer222to be displayed on the image output device202.

Further, by assigning the input device signals of PS/2 CLK and PS/2 DATA to the reserved signal of Terminal4and the ID0 signal of Terminal11, which is normally not used, respectively, it is possible to connect the input device signals of the computer222to the external computer222.

Thus, by providing the projection240and the hook hole242for preventing improper insertion also serving as detection signals (terminals), assigning input device signals used in the external computer222to signals assigned as unused and reserved, and further assigning an input signal that has a pull-up resistor to 5 V power supply and detects connection of the external computer222to terminals already assigned as +5 VDC in the image signal interface connectors244and246, it is possible to expand functions while maintaining compatibility with the existing external image output interface.

A 24thembodiment of the present invention relates to image signal interface connectors that integrate the features of the fifth, sixth, ninth, tenth, and 12thembodiments.FIG. 40is a schematic front view of the image signal female connector246in the computer201and the image signal male connector244on the external computer222side according to the 24thembodiment of the present invention.FIG. 41is a list showing a VGA (VESA DDC) terminal layout according to the 24thembodiment.

According to the 24thembodiment, the +5 VDC terminals of the image signal connectors244and246are assigned as detection terminals that have a +5 V pull-up resistor and detect connection of the external computer222. The detection terminals come into contact with each other before all the other terminals come into contact. Therefore, first, the switch signal A218that controls the input/output of the image input/output switching unit206of the computer201changes from “H” to “L.” As a result, the image signal output to the external image output device (external monitor)212is stopped, so that the image input/output switching unit206can switch to “input node.” Further, after the terminals of the image signal come into contact, the image signal of the external computer222is input to the computer201to be displayed on the image output device202.

Further, by assigning the input device signals of PS/2 CLK and PS/2 DATA to the reserved signal of Terminal4and the ID0 signal of Terminal11, which is normally not used, respectively, it is possible to connect the input device signals of the computer222to the external computer222.

Thus, by assigning input device signals used in the external computer222to signals assigned as unused and reserved, and further assigning an input signal that has a pull-up resistor to 5 V power supply and detects connection of the external computer222to terminals already assigned as +5 VDC in the image signal interface connectors244and246, it is possible to expand functions while having the same conventional connectors and maintaining compatibility with the existing external image output interface.

According to one embodiment of the present invention, there is provided a computer including a switching part configured to detect a connection of an external computer to the computer upon the connection, and to determine, in response to the detection of the connection of the external computer, that an output signal of the external computer be received and output to an output part of the computer.

According to one embodiment of the present invention, there is provided a computer, wherein a connection of an external computer to the computer is detected upon the connection, and it is determined, in response to the detection of the connection of the external computer, that a signal input through an input part of the computer be input to the external computer.

According to one embodiment of the present invention, there is provided a computer including a switching part configured to detect a connection of an external computer to the computer upon the connection; and to determine, in response to the detection of the connection of the external computer, that an output signal of the external computer be received and output to an output part of the computer, and a signal input through an input part of the computer be input to the external computer.

According to one embodiment of the present invention, there is provided a computer including a main body and an input/output part including an input part and an output part, wherein the input/output part is removably provided on the main body.

According to one embodiment of the present invention, there is provided a computer including a main body and an input/output part including an input part and an output part, the input/output part being removably provided on the main body, wherein the input/output part includes a processor including a peripheral device controller, the processor having a processing function as a computer, the processor being configured to be remotely connectable to the main body through data communications.

According to one aspect of the present invention, it is possible to improve the performance of a computer with respect to power consumption, weight, volume, security, and remote operation at the time of its operation. Further, it is also possible to improve the performance of the computer with respect to partial replaceability at the time of failure.

The present application is based on Japanese Priority Patent Application No. 2006-049965, filed on Feb. 27, 2006, the entire contents of which are hereby incorporated by reference.