Patent Publication Number: US-2010130270-A1

Title: Cellular telephone apparatus and control method of the apparatus

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is based on the Japanese Patent Application No. 2008-298020 filed on Nov. 21, 2008, the entire content of which is expressly incorporated by reference herein. 
     FIELD OF THE INVENTION 
     The present invention relates to a cellular telephone apparatus and control method, and more particularly, to a cellular telephone apparatus provided with a part separable from the cellular telephone apparatus and control method of the apparatus. 
     BACKGROUND OF THE INVENTION 
     Conventionally, to enhance convenience in using the videophone function, a cellular telephone apparatus is proposed that an imaging/display unit constituting a part of the cellular telephone apparatus is provided to be separable from the main body of the cellular telephone apparatus (for example, JP 2004-120056). In this cellular telephone apparatus, in using the videophone function, by separating the imaging/display unit from the main body of the cellular telephone apparatus and positioning the unit to face the user&#39;s face, the user is capable of calling in the normal calling posture of putting the apparatus body to the user&#39;s ear, while transmitting an image of the user taken by the image pickup camera to the communicating party, and watching the display section displaying an image transmitted from the communicating party. 
     However, in the aforementioned conventional cellular telephone apparatus, although it is possible to enhance convenience in using the videophone function, there are cases that the convenience decreases in using the other functions installed in the cellular telephone apparatus. In other words, currently, cellular telephone apparatuses have been installed with many functions, and the apparatus is easy to use in some operating function when a part of the cellular telephone apparatus is not separated, while being hard to use when the part is separated. In contrast thereto, in another operating function, the apparatus is easy to use when a part of the cellular telephone apparatus is separated, while being hard to use when the part is not separated. 
     For example, in performing a voice call when the cellular telephone is not separated, the receiver constituting the call receiving section is driven on the apparatus (hereinafter, referred to as a “separate apparatus”) to be separated from the apparatus body, and the microphone constituting the call transmitting section is driven on the apparatus body side. When the user separates the separate apparatus from the apparatus body in this state (for example, when the user wants to check an e-mail or scheduler in the display section on the separate apparatus side while performing a voice call), since the receiver is driven on the separate apparatus side, it becomes hard to hear the voice of the communicating party. Further, in performing a videophone call with the apparatus separated as described above, the receiver and microphone are driven on the apparatus body side, and when the user connects the separate apparatus to the apparatus body in this state (for example, when the user desires a videophone call with the cellular telephone apparatus placed on a desk or the like), it becomes hard to hear the voice of the communicating party driven by the receiver on the apparatus body side. It is preferable that the receiver on the apparatus body side is driven in the former case, and that the receiver driven on the apparatus body side is switched to, for example, the speaker of the separate apparatus to output the voice of the communicating party in the latter case. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a cellular telephone apparatus enabling a part of the cellular telephone apparatus to be separated and used, while ensuring the convenience in various functions installed in the cellular telephone apparatus, and a control method of the apparatus. 
     A cellular telephone apparatus of the invention is a cellular telephone apparatus in which a first apparatus constituting a part of the cellular telephone apparatus is provided to be separable from a second apparatus constituting an apparatus body, and has a detecting section that detects a state of the first apparatus, a table holding section that holds a device table that defines devices driven in various functions of the cellular telephone apparatus corresponding to states of the first apparatus, and a control section that determines devices driven in the first apparatus and the second apparatus according to descriptions of the device table in response to the state of the first apparatus detected in the detecting section. 
     According to this constitution, since the devices driven in various functions are determined in response to the state of the first apparatus constituting a part of the cellular telephone apparatus, it is possible to select and drive devices required to execute various functions, and therefore, it is possible to separate a part of the cellular telephone apparatus to use while ensuring the convenience in various functions installed in the cellular telephone apparatus. 
     In the cellular telephone apparatus of the invention, it is preferable that the detecting section notifies the control section of the state of the first apparatus that has been changed when the detecting section detects a change in the state of the first apparatus, and that the control section judges devices driven in the first apparatus and the second apparatus according to descriptions of the device table in response to the notified state of the first apparatus. In this case, whenever a change is detected in the state of the first apparatus constituting a part of the cellular telephone apparatus, the devices driven in the first apparatus and the second apparatus are judged in response to the state of the first apparatus that has been changed. It is thereby possible to drive suitable devices corresponding to the function operating in the cellular telephone apparatus whenever the state of the part of the cellular telephone apparatus is switched. 
     In the cellular telephone apparatus of the invention, when a change in the state is detected in the function operating in the cellular telephone apparatus, the control section preferably inquires of the detecting section for the state of the first apparatus, and judges devices driven in the first apparatus and the second apparatus according to descriptions of the device table in response to the responded state of the first apparatus. In this case, whenever a change in the state is detected in the function operating in the cellular telephone apparatus, devices driven in the first apparatus and the second apparatus are judged in response to the current state of the first apparatus. It is thereby possible to drive suitable devices corresponding to the switched function whenever the state of the function operating in the cellular telephone apparatus is switched. 
     In the cellular telephone apparatus of the invention, when the control section is instructed to use a particular function that is inoperable in the current state of the first apparatus, the control section preferably informs of the state of the first apparatus enabling the particular function to operate. In this case, even when the control section is instructed to use a particular function that cannot operate in the current state of the first apparatus, the user is informed of the state of the first apparatus enabling the particular function to operate, and it is thus possible to urge the user to change the state of the first apparatus, and the like. 
     In the cellular telephone apparatus of the invention, the device table preferably defines a device driven in a function expected to be used when the state of the first apparatus is switched in the particular function of the cellular telephone apparatus. In this case, when the state of the first apparatus is switched while the particular function is operating in the cellular telephone, it is possible to drive the device driven in the function expected to be used in the switched state of the first apparatus, an input operation by the user can thereby be omitted, and it is possible to provide the cellular telephone apparatus with more excellent operability. 
     For example, in the cellular telephone apparatus of the invention, the device table defines a device driven to use the voice calling function only by the second apparatus when the first apparatus is switched to the separate state in the voice calling function in the cellular telephone apparatus. Further, the device table defines a device driven to use the e-mail processing function only by the first apparatus when the first apparatus is switched to the separate state in the e-mail processing function in the cellular telephone apparatus. Furthermore, the device table defines a device driven to use the browser function only by the first apparatus when the first apparatus is switched to the separate state in the browser function in the cellular telephone apparatus. Still furthermore, the device table defines a device driven to use the speech replay function only by the first apparatus when the first apparatus is switched to the separate state in the speech replay function in the cellular telephone apparatus. 
     A control method of a cellular telephone apparatus of the invention is a control method of a cellular telephone apparatus in which a first apparatus constituting a part of the cellular telephone apparatus is provided to be separable from a second apparatus constituting an apparatus body, and the cellular telephone apparatus holds a device table that defines devices driven in various functions of the cellular telephone apparatus corresponding to states of the first apparatus, and has the steps of detecting a state of the first apparatus, and determining devices driven in the first apparatus and the second apparatus according to descriptions of the device table in response to the state of the first apparatus. 
     According to this method, since the devices driven in various functions are determined in response to the state of the first apparatus constituting a part of the cellular telephone apparatus, it is possible to select and drive devices required to execute various functions, and therefore, it is possible to separate a part of the cellular telephone apparatus to use while ensuring the convenience in various functions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The various features of novelty which characterize the invention are pointed out with particularity in the claims attached to and forming a part of this specification. For a better understanding of the invention, its operating advantages, and specific objects attained by its use, reference should be had to the accompanying drawing and descriptive matter in which there is illustrated and described a preferred embodiment of the invention. 
         FIG. 1  is a diagram showing an appearance of a cellular telephone according to one embodiment of the invention; 
         FIG. 2  is a block diagram illustrating a configuration of a main terminal in the cellular telephone according to the embodiment; 
         FIG. 3  is a block diagram illustrating a configuration of a sub-terminal in the cellular telephone according to the embodiment; 
         FIG. 4  is a diagram to explain descriptions registered with a display table held in a table holding section of the main terminal in the cellular telephone according to the embodiment; 
         FIG. 5  is another diagram to explain descriptions registered with the device table held in the table holding section of the main terminal in the cellular telephone according to the embodiment; 
         FIG. 6  is a sequence diagram to explain operations in determining devices driven in the main terminal and the sub-terminal in the cellular telephone according to the embodiment; 
         FIG. 7  is another sequence diagram to explain operations in determining devices driven in the main terminal and the sub-terminal in the cellular telephone according to the embodiment; 
         FIG. 8  is a sequence diagram to explain operations when the state of the sub-terminal is switched while a particular function is operating where the function becomes inoperable corresponding to the state of the sub-terminal in the cellular telephone according to the embodiment; and 
         FIG. 9  is a diagram to explain variations of the connection form of the sub-terminal to the main terminal of the cellular telephone according to the embodiment. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An embodiment of the present invention will be described below with reference to accompanying drawings. In the following description, the case is described that the present invention is embodied using a cellular telephone apparatus (hereinafter, simply referred to as a “cellular telephone”)  1 , but the invention is not limited thereto, and is achieved also as a control method of the cellular telephone  1 . 
       FIG. 1  is a diagram showing an appearance of the cellular telephone apparatus  1  according to one embodiment of the invention. As shown in  FIG. 1 , the cellular telephone  1  according to this embodiment is comprised of a main terminal  2  formed of an apparatus (second apparatus) installed with main functions of the cellular telephone  1 , and a sub-terminal  3  formed of an apparatus (first apparatus) installed with part of the functions of the cellular telephone  1 . The sub-terminal  3  is provided to be separable from the main terminal  2 , and is configured to execute part of the functions (for example, e-mail check function, music player function, and One Seg function) of the cellular telephone  1  by the sub-terminal  3  by performing near field radio communication, described later, with the main terminal  2 . In addition, the main terminal  2  and sub-terminal  3  are provided to be connectable in a predetermined portion by a magnet, and are capable of being used as a common one-piece cellular telephone in the connected state. 
     For example, such a separable type cellular telephone  1  is suitable for use where the user puts the main terminal  2  into a bag, etc, always wears the sub-terminal  3  as a media player of music and pictures, and only when needing a complicated operation, takes the main terminal  2  out of the bag to operate from the main terminal  2  side. Further, for example, when the user watches one-segment broadcasting in a bath or the like hard to receive radio signals, the cellular telephone  1  is suitable for another usage mode where the user places the main terminal  2  in a position near the window easy to receive radio signals, brings only the sub-terminal  3  to the bath, and receives one-segment broadcasting data from the main terminal  2  to watch. This embodiment is to ensure the convenience in various functions installed in the cellular telephone  1  in using the cellular telephone  1  in a state where the main terminal  2  and sub-terminal  3  are separated (hereinafter, referred to as a “separate state” as appropriate) and in another state where the main terminal  2  and sub-terminal  3  are connected (hereinafter, referred to as a “connected state” as appropriate). 
     Configurations of the main terminal  2  and sub-terminal  3  that the cellular telephone  1  has will be described below using  FIGS. 2 and 3  while referring to the appearance of the cellular telephone  1  as shown in  FIG. 1  as appropriate.  FIGS. 2 and 3  are block diagrams respectively illustrating configurations of the main terminal  2  and sub-terminal  3  that the cellular telephone  1  according to this embodiment has. In addition, the configurations of the cellular telephone  1  as shown in  FIGS. 2 and 3  are simplified to describe the invention, and are assumed to have components that the common cellular telephone  1  has. 
     As shown in  FIG. 2 , the main terminal  2  that the cellular telephone  1  according to this embodiment has is comprised of a control section  21  that controls the entire main terminal  2 , and a radio communication section  22 , short-distance radio communication section  23 , state monitoring section  24 , table holding section  25 , battery section  26  and device group  27  each connected to the control section  21 . Then, the device group  27  installed in the main terminal  2  includes an operating key  271 , receiver  272 , microphone  273  and main camera  274 . 
     The radio communication section  22  performs radio communication with a base station apparatus installed onto a mobile communication network via an antenna apparatus not shown. For example, the radio communication section  22  transmits speech data and packet data from the cellular telephone  1  to the base station apparatus via the mobile communication network in performing speech communication and packet communication with another cellular telephone or the like, while receiving speech data and packet data from the communicating party from the base station apparatus via the mobile communication network. 
     The short-distance radio communication section  23  performs short-distance radio communication with the sub-terminal  3  via the antenna apparatus not shown. In this embodiment, the short-distance radio communication section  23  performs Bluetooth communication, and transmits speech data and image data to the sub-terminal  3 , while receiving requests for various kinds of processing and the like sent from the sub-terminal  3 . In addition, this embodiment shows the case of using Bluetooth in radio communication between the main terminal  2  and sub-terminal  3 , but the communication technique used in radio communication between the terminals  2  and  3  is not limited thereto, and is capable of being modified as appropriate. For example, IrDA (Infrared Data Association) using infrared rays may be applied. 
     The state monitoring section  24  functions as a detecting section that detects the state of the sub-terminal  3  constituting a part of the cellular telephone  1 , and monitors the state (separate state and connected state) of the sub-terminal  3  with respect to the main terminal  2 . The state monitoring section  24  regularly monitors the state of the sub-terminal  3 , and when detecting a change in the state of the sub-terminal  3 , notifies the control section  21  of the change. For example, the state monitoring section  24  is formed of a magnetic sensor, and detects the state of the sub-terminal  3  with respect to the main terminal  2  based on the magnetic intensity and direction changing corresponding to the connected state and separate state of the main terminal  2  and sub-terminal  3 . In addition, this embodiment shows the case of using a magnetic sensor in detection of the connected state and separate state of the main terminal  2  and sub-terminal  3 , but the configuration for detecting the states is not limited thereto, and is capable of being modified as appropriate. 
     The table holding section  25  holds a device table that defines devices driven in various functions installed in the cellular telephone  1  corresponding to the states (connected state and separated state) of the sub-terminal  3  with respect to the main terminal  2 . With the device table is registered whether or not to drive various devices (for example, operating key  271  of the main terminal, touch panel  342  of the sub-terminal described later) that the main terminal  2  and sub-terminal  3  of the cellular telephone  1  have in association with various functions (for example, voice calling function, e-mail processing function, etc.) installed in the cellular telephone  1 . In addition, details of descriptions registered with the device table will be described later. 
     The battery section  26  is a portion that supplies power required for the main terminal  2  to operate. The battery section  26  is provided to be detachable from a battery storage section provided in the main terminal  2 , and is configured to be capable of being charged by a charger not shown. The main terminal  2  is designed to be able to operate for a predetermined time corresponding to driving conditions of various devices and radio communication conditions when the battery section  26  is charged with the main terminal  2  being independent or with the main terminal  2  connected to the sub-terminal  3 . 
     The operating key  271  constituting a part of the device group  27  receives an operation from the user, and is comprised of a numeric keypad for receiving numeric and text inputs, a direction key for moving a cursor displayed on a main display  341  of the sub-terminal  3  described later, a determination key for selecting information specified by movement of the cursor, and function keys associated with particular functions. 
     The receiver  272  comprises a call receiving section, and outputs a voice of a communicating party in using the voice calling function and videophone function with the sub-terminal  3  separated. Further, the receiver  272  outputs speech data in one-segment broadcasting when the one-segment broadcasting receiving function (hereinafter, referred to as “One Seg function” as appropriate) is used with the sub-terminal  3  separated. 
     The microphone  273  comprises a call transmitting section, and receives a user&#39;s voice in using the voice calling function and videophone function irrespective of the state of the sub-terminal  3  (in other words, irrespective of whether the sub-terminal  3  is in the connected state or separate state). In addition, the sensitivity of the microphone  273  in using the videophone function is higher than the sensitivity in using the voice calling function. 
     The main camera  274  is used as a main image pickup apparatus in using the camera function. In addition, this main camera  274  is provided on the back of the main terminal  2  and does not appear in the main terminal  2  as shown in  FIG. 1 . Further, in the main terminal  2  as shown in  FIG. 1 , a sub-display  275  is provided above the operating key  271 . For example, the sub-display  275  displays information regarding remaining battery power in the main terminal  2  and the sub-terminal  3 , etc. but is omitted from the device group  27  as shown in  FIG. 2  to simplify the descriptions of the invention. 
     The control section  21  controls these components and determines devices driven in the main terminal  2  and sub-terminal  3  according to descriptions of the device table in response to the state (separated state or connected state) of the sub-terminal  3  with respect to the main terminal  2  by the state monitoring section  24  when various functions installed in the cellular telephone  1  operate. 
     As shown in  FIG. 3 , the sub-terminal  3  that the cellular telephone  1  according to this embodiment has is comprised of a control section  31  that controls the sub-terminal  3 , and a short-distance radio communication section  32 , battery section  33  and device group  34  each connected to the control section  31 . In the illustrated embodiment, the device group  34  installed in the sub-terminal  3  includes a display  341 , touch panel  342 , receiver  343 , sub-camera  344 , and speaker  345 . 
     The short-distance radio communication section  32  performs short-distance radio communication with the main terminal  2  via an antenna apparatus not shown. For example, the short-distance radio communication section  32  performs Bluetooth communication as in the short-distance radio communication section  23  on the main terminal  2  side, and receives speech data and image data from the main terminal  2 , while transmitting requests for various kinds of processing and the like to the main terminal  2 . 
     The battery section  33  is a portion that supplies power required for the sub-terminal  3  to operate. The battery section  33  is provided to be detachable from a battery storage section provided in the sub-terminal  3 , and is configured to be capable of being charged by a charger not shown. The sub-terminal  3  is designed to be able to operate for a predetermined time corresponding to driving conditions of various devices and short-distance radio communication conditions when the battery section  33  is charged with the sub-terminal  3  being independent. 
     The display  341  constituting a part of the device group  34  forms a main display of the cellular telephone  1 , and displays screen data and picture data used in various functions operating in the cellular telephone  1 . For example, when the voice calling function operates, the display  341  displays a screen (in-progress call screen) indicative of a call being in progress, and when the e-mail processing function operates, the display  341  displays a screen (e-mail screen) enabling the user to check and create an e-mail, etc. Further, when the videophone function operates, for example, the display  341  displays a face image of the communicating party, and when the One Seg function operates, the display  341  displays picture data in one-segment broadcasting. Furthermore, the display  341  displays an operation screen (for example, menu screen) corresponding to an input area of the touch panel  342  described later when the touch panel  342  receives an operation of the user. 
     The touch panel  342  is disposed in the lower layer portion of the display  341 , and is a portion constituting an operation section when the sub-terminal  3  operates independently. In the touch panel  342  are formed input areas corresponding to the operation screen used in various functions operating in the cellular telephone  1 , and it is possible to receive a user desired input operation. For example, when the user uses the e-mail processing function using the sub-terminal  3  alone, formed are input areas corresponding to an e-mail screen displaying a list of e-mails to check. When the user selects an input area corresponding to a desired e-mail from the e-mail screen, the display  341  displays the content of the e-mail. 
     The receiver  343  is a portion constituting a call receiving section, and outputs a voice of a communicating party in using the voice calling function with the sub-terminal  3  connected to the main terminal  2 . In the following description, although the case is shown that the receiver  343  is not driven with the sub-terminal  3  separated from the main terminal  2 , for example, a configuration may be adopted that the voice calling function can be used only by the sub-terminal  3  separated from the main terminal  2 . In this case, it is preferable that the sub-terminal  3  is provided with a microphone equivalent to the microphone  273  of the main terminal  2 , and that the receiver  343  outputs the voice of the communicating party. 
     The sub-camera  344  is used as an image pickup device to shoot a face image of the user when the videophone function is used. In addition, this sub-camera  344  may be used in the camera function. 
     The speaker  345  outputs a voice of a communicating party when the videophone function is used with the sub-terminal  3  connected to the main terminal  2 . Further, the speaker  345  outputs speech data of one-segment broadcasting when the One Seg function is used irrespective of the state of the sub-terminal  3  (in other words, irrespective of whether the sub-terminal  3  is in the connected state or separate state). 
     The control section  31  controls these components. Particularly, the control section  31  selects and drives a device used in the function operating in the cellular telephone  1  corresponding to the state of the sub-terminal  3  with respect to the main terminal  2 , under control of the control section  21  on the main terminal  2  side. For example, in the case that the voice calling function is operating, the control section  31  does not drive the touch panel  342  to be inoperable when the sub-terminal  3  is in the connected state, while driving the touch panel  342  to be operable when the sub-terminal  3  is in the separate state. 
     Described herein are descriptions of the device table held in the table holding section  25  of the main terminal  2  that this embodiment has.  FIGS. 4 and 5  are diagrams to explain descriptions registered with the device table held in the table holding section  25  of the main terminal  2  that this embodiment has. In addition, the functions of the cellular telephone  1  managed in the device table as shown in  FIGS. 4 and 5  are indicated as an example, and the invention is not limited thereto. For example, it is possible to register any function that is the function installed in the cellular telephone  1  and that requires control of driving of devices in the main terminal  2  and sub-terminal  3  corresponding to the state of the sub-terminal  3 . Further, devices of the cellular telephone  1  (main terminal  2  and sub-terminal  3 ) managed in the device table as shown in  FIGS. 4 and 5  are indicated as an example, and the invention is not limited thereto. For example, it is possible to register any device that is the device provided in the cellular telephone  1  and that needs to be controlled corresponding to the function under operating conditions and the state of the sub-terminal  3 . 
     As shown in  FIGS. 4 and 5 , with the device table are registered driving conditions of various devices provided in the cellular telephone  1  (main terminal  2 , sub-terminal  3 ) in association with the state (connected state, separate state) of the sub-terminal  3  in the function (operating function) operating in the cellular telephone  1 . More specifically, the states (connected state, separate state) of the sub-terminal  3  are registered in the “voice calling function”, “e-mail processing function”, “videophone function”, “browser function”, “One Seg function”, “camera function”, and “music (M) player function” as the function operating in the cellular telephone  1 , and registered as devices provided in the cellular telephone  1  (main terminal  2 , sub-terminal  3 ) are the “display (sub-terminal side)”, “operating key (main terminal side)”, “touch panel (sub-terminal side)”, “receiver (main terminal side)”, “receiver (sub-terminal side)”, “microphone (main terminal side)”, “speaker (sub-terminal side)”, “main camera (main terminal side)”, and “sub-camera (sub-terminal side)”. 
     As shown in  FIG. 4 , when the voice calling function is the operating function while the sub-terminal  3  is in the connected state, the display  341  of the sub-terminal  3  displays a screen (in-progress call screen) indicative of a call being in progress, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. Further, the receiver  272  of the main terminal  2  is made OFF, while the receiver  343  of the sub-terminal  3  is made ON. Furthermore, the microphone  273  of the main terminal  2  is made ON, while the speaker  345  of the sub-terminal  3  is made OFF. In contrast thereto, when the sub-terminal  3  is in the separate state, the display  341  of the sub-terminal  3  displays a menu screen, and the operating key  271  of the main terminal  2  is made inoperable, while the touch panel  342  of the sub-terminal  3  is made operable. Further, the receiver  272  of the main terminal  2  is made ON, while the receiver  343  of the sub-terminal  3  is made OFF. Furthermore, the microphone  273  of the main terminal  2  is made ON, while the speaker  345  of the sub-terminal  3  is made OFF. In other words, when the voice calling function is the operating function, the display content of the display  341  is switched corresponding to the state of the sub-terminal  3 , while the states of the operating key  271 , touch panel  342 , receiver  272  and receiver  343  are switched. 
     When the sub-terminal  3  is switched from the connected state to the separate state while the voice calling function is operating, it is expected to search for data (address book, e-mail, scheduler, etc.) while continuing the voice call. Therefore, in the cellular telephone  1  according to this embodiment, such a registered description is registered with the device table that the display  341  displays the menu screen while the touch panel  342  is made operable, and the convenience is thereby improved when the voice calling function operates. More specifically, such a registered description is registered with the device table that a device (herein, for example, the touch panel  342 ) is made operable where the device is driven in a function (for example, the e-mail processing function) expected to be used when the state of the sub-terminal  3  is switched during the operation of the voice calling function, and it is thereby possible to omit an input operation by the user and to further improve the operability in the cellular telephone  1 . Moreover, when the sub-terminal  3  is switched to the separate state, since it is required to enable the voice call to be performed by the main terminal  2  alone, driving of the receiver  343  of the sub-terminal  3  is halted, while the receiver  272  of the main terminal  2  is driven. By this means, the user is capable of continuing the voice call by the main terminal  2  alone by separating the sub-terminal  3  from the main terminal  2 , while making a data search or the like on the sub-terminal  3  side. On the other hand, when the sub-terminal  3  is switched from the separate state to the connected state, since it is expected to perform the voice call in the common calling posture, the display content of the display  341  is returned to the original state (i.e. the connected state as shown in  FIG. 4 ) corresponding to the state of the sub-terminal  3 , while the states of the operating key  271 , touch panel  342 , receiver  272  and receiver  343  are also returned to the original states. 
     In addition, the reason why the operating key  271  of the main terminal  2  is made inoperable when the sub-terminal  3  is separated is to prevent the operability from degrading due to a conflict between operation inputs from the main terminal  2  and sub-terminal  3 . By thus exclusively controlling operation inputs from the main terminal  2  and sub-terminal  3 , deterioration of the operability is prevented in the cellular telephone  1 . However, it is naturally possible to receive operation inputs from both of the main terminal  2  and sub-terminal  3 . 
     Further, when the e-mail processing function is the operating function while the sub-terminal  3  is in the connected state, the display  341  of the sub-terminal  3  displays a screen (e-mail screen) enabling the user to check and create an e-mail, etc. and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. In contrast thereto, when the sub-terminal  3  is in the separate state, the display  341  of the sub-terminal  3  displays an e-mail screen, and the operating key  271  of the main terminal  2  is made inoperable, while the touch panel  342  of the sub-terminal  3  is made operable. In other words, when the e-mail processing function is the operating function, the states of the operating key  271  and touch panel  342  are switched corresponding to the state of the sub-terminal  3 . 
     When the sub-terminal  3  is switched to the separate state while the e-mail processing function is operating, it is expected to continue the e-mail processing by the sub-terminal  3  alone. Therefore, in the cellular telephone  1  according to this embodiment, the operating key  271  of the main terminal  2  is switched to be inoperable, while the touch panel  342  of the sub-terminal  3  is switched to be operable. By this means, the user is capable of continuing the e-mail processing by the sub-terminal  3  alone only by separating the sub-terminal  3  from the main terminal  2 . On the other hand, when the sub-terminal  3  is switched from the separate state to the connected state, since it is expected to perform the e-mail processing in the attitude of the common one-piece cellular telephone  1 , the states of the operating key  271  and touch panel  342  are returned to the original states (i.e. the connected state as shown in  FIG. 4 ). 
     Further, when the videophone function is the operating function while the sub-terminal  3  is in the connected state, the display  341  of the sub-terminal  3  displays a videophone screen, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. Further, the receiver  272  of the main terminal  2  and the receiver  343  of the sub-terminal  3  are made OFF, while the microphone  273  of the main terminal  2  and the speaker  345  of the sub-terminal  3  are made ON. In addition, the main camera  274  of the main terminal  2  and the sub-camera  344  of the sub-terminal  3  are dependent on the user advance setting. In contrast thereto, when the sub-terminal  3  is in the separate state, the display  341  of the sub-terminal  3  displays a videophone screen, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. Further, the receiver  272  of the main terminal  2  is made ON, while the receiver  343  of the sub-terminal is made OFF. Furthermore, the microphone  273  of the main terminal  2  is made ON, while the speaker  345  of the sub-terminal  3  is made OFF. Furthermore, the main camera  274  of the main terminal  2  is made OFF, while the sub-camera  344  of the sub-terminal  3  is made ON. In other words, when the videophone function is the operating function, the states of the receiver  272  and speaker  345  are switched corresponding to the state of the sub-terminal  3 , and the states of the main camera  274  and sub-camera  344  are switched as necessary. 
     When the sub-terminal  3  is switched from the connected state to the separate state while the videophone function is operating, it is expected to talk while placing the sub-terminal  3  in front of the user&#39;s face and putting the main terminal  2  to the user&#39;s ear. Therefore, in the cellular telephone  1  according to this embodiment, the receiver  272  of the main terminal  2  is driven, while driving of the speaker  345  of the sub-terminal  3  is halted. By this means, the user is capable of performing the videophone call in the talking posture as described above only by separating the sub-terminal  3  from the main terminal  2 . On the other hand, when the sub-terminal  3  is switched from the separate state to the connected state, since it is expected to perform the videophone call while placing the cellular telephone  1  on a desk or the like, the states of the receiver  272  and speaker  345  are returned to the original states (i.e. the connected state as shown in  FIG. 4 ), and the states of the main camera  274  and sub-camera  344  are also returned to the original states as necessary. 
     Further, when the browser function is the operating function while the sub-terminal  3  is in the connected state, the display  341  of the sub-terminal  3  displays a browser, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. In contrast thereto, when the sub-terminal  3  is in the separate state, the display  341  of the sub-terminal  3  displays a browser, and the operating key  271  of the main terminal  2  is made inoperable, while the touch panel  342  of the sub-terminal  3  is made operable. In other words, when the browser function is the operating function, as in the e-mail processing function, the states of the operating key  271  and touch panel  342  are switched corresponding to the state of the sub-terminal  3 . 
     When the sub-terminal  3  is switched to the separate state while the browser function is operating, it is expected to continue the browsing processing by the sub-terminal  3  alone. Therefore, in the cellular telephone  1  according to this embodiment, the operating key  271  of the main terminal  2  is switched to be inoperable, while the touch panel  342  of the sub-terminal  3  is switched to be operable. By this means, the user is capable of continuing the browsing processing using the sub-terminal  3  alone only by separating the sub-terminal  3  from the main terminal  2 . On the other hand, when the sub-terminal  3  is switched from the separate state to the connected state, since it is expected to perform the browsing processing in the attitude of the common one-piece cellular telephone  1 , the states of the operating key  271  and touch panel  342  are returned to the original states. 
     As shown in  FIG. 5 , when the One Seg function is the operating function while the sub-terminal  3  is in the connected state, the display  341  of the sub-terminal  3  displays picture data in the One Seg direction in a vertical screen, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. Further, the speaker  345  of the sub-terminal  3  is made ON. In contrast thereto, when the sub-terminal  3  is in the separate state, the display  341  of the sub-terminal  3  displays picture data of one-segment broadcasting in a horizontal screen, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. Further, the receiver  272  of the main terminal  2  is made ON corresponding to the user setting, while the speaker  345  of the sub-terminal  3  is made ON. In other words, when the One Seg function is the operating function, the display content of the display  341  is switched corresponding to the state of the sub-terminal  3 , while the state of the receiver  272  is switched corresponding to the user setting. 
     When the sub-terminal  3  is switched from the connected state to the separate state while the One Seg function is operating, it is expected to place the sub-terminal  3  on a desk or the like to use the main terminal  2  like a remote controller. In the cellular telephone  1  according to this embodiment, the operating key  271  is maintained at the operable state, while the touch panel  342  is maintained at the inoperable state. Further, generally, the speech data of one-segment broadcasting is output from the speaker  345  of the sub-terminal  3 , and in the separate state, it is also possible to output the speech data from the receiver  272  of the main terminal  2 . Therefore, in the cellular telephone  1  according to this embodiment, the receiver  272  is driven corresponding to the user setting. In addition, in this case, it is preferable to halt driving of the speaker  345  of the sub-terminal  3 . By this means, the user is capable of watching one-segment broadcasting calmly by adopting the posture of putting the main terminal  2  to the user&#39;s ear without using an earphone or the like. On the other hand, when the sub-terminal  3  is switched from the separate state to the connected state, it is expected to watch one-segment broadcasting in the form of the common one-piece cellular telephone  1 , and therefore, the state of the receiver  272  is returned to the original state (i.e. the connected state as shown in  FIG. 5 ) as necessary. 
     When the sub-terminal  3  is switched to the separate state while the One Seg function is operating, it is also expected to watch one-segment broadcasting by the sub-terminal  3  alone. In this case, in the cellular telephone  1  according to this embodiment, it is preferable to switch the operating key  271  of the main terminal  2  to be inoperable, while switching the touch panel  342  of the sub-terminal  3  to be operable. By this means, the user is capable of watching one-segment broadcasting using the sub-terminal  3  alone only by separating the sub-terminal  3  from the main terminal  2 . 
     Further, when the camera function is the operating function while the sub-terminal  3  is in the connected state, the display  341  of the sub-terminal  3  displays a finder screen, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. In addition, the main camera  274  of the main terminal  2  and the sub-camera  344  of the sub-terminal  3  are dependent on the user advance setting. In contrast thereto, when the sub-terminal  3  is in the separate state, the display  341  of the sub-terminal  3  displays a finder screen, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. Further, the main camera  274  of the main terminal  2  is made ON, while the sub-camera  344  of the sub-terminal  3  is made OFF. In other words, when the camera function is the operating function, the states of the main camera  274  and sub-camera  344  are switched corresponding to the state of the sub-terminal  3 . 
     When the sub-terminal  3  is switched from the connected state to the separate state while the camera function is operating, it is expected to check the finder screen with the display  341  of the sub-terminal  3 , while performing imaging processing in the main camera  274  of the main terminal  2 . Therefore, in the cellular telephone  1  according to this embodiment, the states of the main camera  274  of the main terminal  2  and the sub-camera  344  of the sub-terminal  3  driven (not driven) by user setting are switched when necessary. By this means, the user is capable of checking the finder screen with the display  341  of the sub-terminal  3 , while performing the imaging processing in the main camera  274  of the main terminal  2  as described above only by separating the sub-terminal  3  from the main terminal  2 . On the other hand, when the sub-terminal  3  is switched from the separate state to the connected state, since it is expected to perform the imaging processing in the attitude of the common one-piece cellular telephone  1 , the states of the main camera  274  of the main terminal  2  and the sub-camera  344  of the sub-terminal  3  are returned to the original states (i.e. the connection state as shown in  FIG. 5 ) 
     Further, when the music player function is the operating function while the sub-terminal  3  is in the connected state, the display  341  of the sub-terminal  3  displays a music player screen enabling the user to replay and halt desired music, check music being replayed and the like, and the operating key  271  of the main terminal  2  is made operable, while the touch panel  342  of the sub-terminal  3  is made inoperable. In contrast thereto, when the sub-terminal  3  is in the separate state, the display  341  of the sub-terminal  3  displays the music player screen, and the operating key  271  of the main terminal  2  is made inoperable, while the touch panel  342  of the sub-terminal  3  is made operable. In other words, when the music player function is the operating function, the states of the operating key  271  and touch panel  342  are switched corresponding to the state of the sub-terminal  3 . 
     When the sub-terminal  3  is switched to the separate state while the music player function is operating, it is expected to continue replay of music and the like by the sub-terminal  3  alone. Therefore, in the cellular telephone  1  according to this embodiment, the operating key  271  of the main terminal  2  is switched to be inoperable, while the touch panel  342  of the sub-terminal  3  is switched to operable. By this means, the user is capable of continuing replay of music and the like only by separating the sub-terminal  3  from the main terminal  2 . On the other hand, when the sub-terminal  3  is switched from the separate state to the connected state, since it is expected to perform replay of music and like in the attitude of the common one-piece cellular telephone  1 , the states of the operating key  271  and touch panel  342  are returned to the original states (i.e. the connection state as shown in  FIG. 5 ). 
     In the cellular telephone  1  according to this embodiment, the table holding section  25  holds the device table with thus registered table data, and the control section  21  of the main terminal  2  determines devices driven in the main terminal  2  and sub-terminal  3  according to the descriptions of the device table corresponding to the state (separate state, connected state) of the sub-terminal  3  detected in the state monitoring section  24 . Thus, since the control section  21  determines devices driven in various functions in response to the state of the sub-terminal  3  with respect to the main terminal  2 , it is possible to select and drive devices required to execute various functions, and therefore, it is possible to separate a part of the cellular telephone  1  (sub-terminal  3 ) to use while ensuring the convenience in various functions installed in the cellular telephone  1 . 
     Described next are operations in determining devices driven in the main terminal  2  and sub-terminal  3  in the cellular telephone  1  according to this embodiment. In the cellular telephone  1  according to this embodiment, when the state monitoring section  24  detects a change in the state of the sub-terminal  3  and when the control section  21  detects a change in the state of the operating function, the control section  21  performs the operation of determining devices driven in the main terminal  2  and sub-terminal  3 . 
     Referring to  FIG. 6 , described first is the operation of determining devices driven in the main terminal  2  and sub-terminal  3  when the state monitoring section  24  detects a change in the state of the sub-terminal  3 .  FIG. 6  is a sequence diagram to explain the operation in determining devices driven in the main terminal  2  and the sub-terminal  3  when the state monitoring section  24  detects a change in the state of the sub-terminal  3  in the cellular telephone  1  according to this embodiment. In addition, the control section  21  is assumed to always monitor the function (operating function) operating in the cellular telephone  1  and grasp the function. 
     In the cellular telephone  1  according to this embodiment, the state monitoring section  24  always monitors whether the state (connected state, separate state) of the sub-terminal  3  changes with respect to the main terminal  2 . Then, as shown in  FIG. 6 , when the state monitoring section  24  detects a state change of the sub-terminal  3  (step S 601 ), the section  24  outputs state change notification of the sub-terminal  3  to the control section  21  (step S 602 ). In addition, this state change notification includes the changed state of the sub-terminal  3 . Upon receiving this state change notification suitably, the control section  21  outputs a state change response indicative of the reception to the state monitoring section  24  (step S 603 ). 
     Upon receiving this state change notification, the control section  21  outputs a request (correspondence table acquisition request) for acquisition of table data corresponding to the function (operating function) operating in the cellular telephone  1  to the table holding section  25  (step S 604 ). Upon receiving this correspondence table acquisition request, the table holding section  25  outputs a correspondence table acquisition response including the table data (hereinafter, referred to as a “correspondence table” as appropriate) corresponding to the currently operating function among the device tables as shown in  FIGS. 4 and 5  to the control section  21  (step S 605 ). 
     Upon receiving the correspondence table from the table holding section  25 , the control section  21  determines devices driven in the cellular telephone  1  (main terminal  2 , sub-terminal  3 ) from the state of the sub-terminal  3  included in the state change notification and the correspondence table included in the correspondence table acquisition response (step S 606 ). Then, the control section  21  instructs corresponding devices to perform operations according to the correspondence table (step S 607 ). Upon receiving this instruction suitably, each of the devices outputs a response indicative of the reception to the control section  21  (step S 608 ). Thus, when the state monitoring section  24  detects a state change of the sub-terminal  3 , the devices driven in the main terminal  2  and sub-terminal  3  are determined and driven. In this case, whenever a change is detected in the state of the sub-terminal  3 , the devices driven in the sub-terminal  3  and main terminal  2  are judged in response to the state of the sub-terminal  3  that has been changed. It is thereby possible to drive suitable devices corresponding to the function operating in the cellular telephone  1  whenever the state of the sub-terminal  3  is switched. 
     Referring to  FIG. 7 , described next is the operation of determining devices driven in the main terminal  2  and sub-terminal  3  when the control section  21  detects a change in the operating function.  FIG. 7  is a sequence diagram to explain the operation in determining devices driven in the main terminal  2  and the sub-terminal  3  when the control section  21  detects a change in the operating function in the cellular telephone  1  according to this embodiment. In addition, the state monitoring section  24  is assumed to always monitor the state (connected state, separate state) of the sub-terminal  3  with respect to the main terminal  2  and grasp the state. 
     In the cellular telephone  1  according to this embodiment, the control section  21  always monitors whether the state is changed in the function (operating function) operating in the cellular telephone  1 . Then, as shown in  FIG. 7 , when a change is detected in the state of the operating function (step S 701 ), the control section  21  outputs a request (sub-terminal state acquisition request) for acquisition of the state of the sub-terminal  3  to the state monitoring section  24  (step S 702 ). Upon receiving this sub-terminal state acquisition request, the state monitoring section  24  outputs a sub-terminal state acquisition response including the state of the sub-terminal  3  to the control section  21  (step S 703 ). 
     Upon receiving this sub-terminal state acquisition response, the control section  21  outputs a request (correspondence table acquisition request) for acquisition of the correspondence table of the function (operating function) currently operating in the cellular telephone  1  to the table holding section  25  (step S 704 ). Upon receiving this correspondence table acquisition request, the table holding section  25  outputs a correspondence table acquisition response including the correspondence table of the currently operating function among the device tables as shown in  FIGS. 4 and 5  to the control section  21  (step S 705 ). 
     Upon receiving the correspondence table from the table holding section  25 , the control section  21  determines devices driven in the cellular telephone  1  (main terminal  2 , sub-terminal  3 ) from the state of the sub-terminal included in the sub-terminal state acquisition response and the correspondence table included in the correspondence table acquisition response (step S 706 ). Then, the control section  21  instructs corresponding devices to perform operations according to the correspondence table (step S 707 ). Upon receiving this instruction suitably, each of the devices outputs a response indicative of the reception to the control section  21  (step S 708 ). Thus, when the control section  21  detects a state change of the operating function, the devices driven in the main terminal  2  and sub-terminal  3  are determined and driven. In this case, whenever a change is detected in the state of the function operating in the cellular telephone  1 , the devices driven in the sub-terminal  3  and main terminal  2  are judged in response to the current state of the sub-terminal  3 . It is thereby possible to drive suitable devices corresponding to the switched function whenever the state of the function operating in the cellular telephone  1  is switched. 
     Meanwhile, in the cellular telephone  1  according to this embodiment, devices required to execute each function are selected and driven in response to the state (connected state, separate state) of the sub-terminal  3  with respect to the main terminal  2 , and such a case may occur that some function is not usable depending on the state of the sub-terminal  3 . For example, in the case where such a function exists that is only usable when the sub-terminal  3  is connected to the main terminal  2 , the function cannot be used when the sub-terminal  3  is in the separate state. As such a function, for example, considered is a function usable only with the main terminal  2  connected to the sub-terminal  3  from the viewpoint of security. In the case where such a function is the operating function, for example, when the sub-terminal  3  is separated, it is preferable to inform the user that the function cannot be used, while informing the user of the state (herein, connected state) of the sub-terminal  3  enabling the function to be used. 
     In the cellular telephone  1  according to this embodiment, for example, it is registered that any device does not exist that can be driven in association with the state (in the aforementioned example, separate state) of the sub-terminal  3  in the corresponding function, the control section  21  informs the user of the aforementioned matter corresponding to the registered description, and it is thereby possible to cope with the situation as described above. Referring to  FIG. 8 , described below is the operation when the sub-terminal  3  shifts to the state where some function becomes inoperable in the case that the function, which becomes inoperable corresponding to the state of the sub-terminal  3 , is the operating function.  FIG. 8  is a sequence diagram to explain the operation when the sub-terminal  3  shifts to the state where some function becomes inoperable in the case that the function, which becomes inoperable corresponding to the state of the sub-terminal  3 , is the operating function in the cellular telephone  1  according to this embodiment. In addition, in  FIG. 8 , the description is made according to the sequence ( FIG. 6 ) of the case where the state monitoring section  24  detects a change in the state of the sub-terminal  3 , but it is possible to the similar processing according to the sequence ( FIG. 7 ) of the case where the control section  21  detects a change in the state of the operating function. In addition, in  FIG. 8 , the common processing with  FIG. 6  is assigned the same reference numeral and the description thereof is omitted. 
     The processing (steps S 601  to S 605 ) is the same as in the sequence as shown in  FIG. 6  of from detection of a state change of the sub-terminal  3  by the state monitoring section  24  to transmission of a correspondence table acquisition response to the control section  21  from the table holding section  25 . In the case of the sequence as shown in  FIG. 8 , upon receiving a correspondence table from the table holding section  25 , the control section  21  judges that the operating function cannot be used in the current state of the sub-terminal  3  from the state of the sub-terminal  3  included in the state change notification and the correspondence table included in the correspondence table acquisition response (step S 801 ). Then, when the control section  21  thus judges that the operating function cannot be used, the section  21  outputs a display request for a message of warning to the display  341  of the sub-terminal  3  (step S 802 ). In this case, the message of warning includes a description that the operating function cannot be used in the current state of the sub-terminal  3  and the state of the sub-terminal  3  enabling the operating function to be used. Upon receiving this display request suitably, the display  341  outputs a response indicative of the reception to the control section  21  (step S 803 ). 
     The message of warning is displayed in the display  341  receiving this display request. By this means, it is possible to inform the user that the operating function cannot be used in the current state of the sub-terminal  3 , and of the state of the sub-terminal  3  enabling the operating function to be used, and therefore, it is possible to urge the user to suspend the operating function, change the state of the sub-terminal  3  and the like. 
     The present invention is not limited to the above-mentioned embodiment, and is capable of being carried into practice with various modifications thereof. For example, the processing sections and processing procedures are capable of being carried into practice with modifications thereof as appropriate without departing from the scope of the invention. Moreover, the invention is capable of being carried into practice with modifications thereof as appropriate without departing from the scope of the invention. 
     For example, the above-mentioned embodiment describes the case of determining devices to be driven in association with the currently operating function corresponding to the state (connected state, separate state) of the sub-terminal  3  with respect to the main terminal  2  in the cellular telephone  1 . Alternately, a plurality of connection forms is prepared in the case that the sub-terminal  3  is connected, and devices to be driven may be adjusted corresponding to the connection form. For example, in the above-mentioned embodiment, devices to be driven are defined based on the premise of the connection form of the sub-terminal  3  corresponding to the clamshell type cellular telephone  1  as shown in  FIG. 9(   a ). Alternately, connection forms may be prepared corresponding to the cellular telephone  1  having the cycloidal hinge structure enabling the sub-terminal  3  to rotate 90 degrees with respect to the main terminal  2  with the telephone  1  opened as shown in  FIG. 9(   b ), or connection forms may be prepared corresponding to the double-open type cellular telephone  1  where the sub-terminal  3  is opened both in the vertical direction and horizontal direction with respect to the main terminal  2 , and devices to be driven may be adjusted corresponding to the type of the connection forms of the sub-terminal  3 . In this case, since devices can be selected and driven corresponding to the type of the connection forms of the sub-terminal  3 , it is possible to select devices to be driven finely corresponding to the usage form of the cellular telephone  1 , and it is made possible to provide the cellular telephone  1  more excellent in convenience.