Abstract:
A method, apparatus, and a non-transitory computer readable medium allows a terminal to concurrently receive control input from multiple secondary devices through a short distance communication mode. The terminal is connected with at least two secondary devices in the short distance communication mode. A key map is applied to the connected secondary devices. When a key signal is received from at least one of the connected secondary devices, the secondary device that transmitted the key signal is identified. And a function mapped to the key signal is executed according to the key map applied to the identified secondary device.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) AND CLAIM OF PRIORITY 
     The present application is related to and claims the benefit of priority under 35 U.S.C. §119(a) to a Korean patent application filed in the Korean Intellectual Property Office on Nov. 18, 2009, and assigned Serial No. 10-2009-0111624, the entire disclosure of which is hereby incorporated by reference. 
     TECHNICAL FIELD OF THE INVENTION 
     The present invention relates to a terminal connecting with a secondary device using short distance communication such as Bluetooth® communication and a method for controlling a function therein. In particular, the present invention relates to a terminal that connects with a secondary device using short distance communication such as Bluetooth® communication and a method for executing a function according to a key signal from a plurality of secondary devices. 
     BACKGROUND OF THE INVENTION 
     With increased spreading of terminal use, data communications for receiving and holding data for other persons by a user terminal, or transmitting user&#39;s data to another terminal, has been developed. There are short distance communication means (such as cable communication, infrared communication, or Bluetooth® communication) and long distance communication means (such as a wireless LAN) of data communication. Short distance communication is achieved between terminals that are within close proximity, and long distance communication is achieved between long distance terminals. 
     In the Bluetooth® communication, communication devices located within 10 meters (m) are connected to each other, and may transmit and receive data using a wireless communication standard that enables two-way communication in a real-time manner. Bluetooth® is a registered trademark owned by the Bluetooth® SIG. A terminal can exchange data using an Industrial Scientific Medical (ISM) band of 2.4 GHz with other communication devices at a speed of 1 Mbps without cable connection according to Bluetooth® communication. A secondary device such as a headset, a hands-free, and a remote controller are examples of communication devices that can connect with a terminal using Bluetooth® communication. 
     A connection method between the terminal and the secondary device through Bluetooth® communication is as follows. 
     When a user selects a Bluetooth® function, a terminal searches for secondary devices within close proximity that are capable of performing a peripheral Bluetooth® function. When a user selects a desired secondary device among detected secondary devices, the terminal transmits a signal requesting Bluetooth® connection to the selected secondary device. At this time, the terminal transmits includes a user&#39;s address in the signal. 
     When the secondary device receives a signal requesting the connection, it transmits a response signal including the user&#39;s address to the terminal. The secondary device may also transmit type information indicating whether it is a headset, an earphone, or a portable terminal, the number of keys that it has, and information with respect to mapped functions by keys. When the terminal receives the information, it checks an address of the secondary device identified in the response signal and calls the secondary device using the checked address. 
     Upon receiving the response signal from the called secondary device, the terminal executes wireless communication connection according to a profile. Next, the terminal and the secondary device form a link for transmitting and receiving data. In addition, the terminal and the secondary device transmit and receive data through the formed link. The terminal and the secondary device connected through Bluetooth® communication will now be illustrated in detail with reference to  FIG. 1 . The secondary device is described assuming that it is a headset. 
       FIG. 1  illustrates a terminal and a secondary device connected by Bluetooth® communication according to the principles of the present disclosure. 
     Referring to  FIG. 1 , a terminal  100  connects with a headset  200  (i.e. a secondary device) using Bluetooth® communication. When the terminal  100  receives a command  110  requesting music data to be output from the headset  200 , it transmits an audio stream  120  corresponding to the music requested to the headset  120 . 
     In general, at least one secondary device is connected to a terminal using Bluetooth® communication. Further, the terminal may execute a function according to a control signal received from the secondary device. However, when multiple secondary devices connect with one terminal, the terminal may transmit specific data to the secondary devices but may not execute a function according to a control signal received from the secondary device. 
     SUMMARY OF THE INVENTION 
     To address the above-discussed deficiencies of the prior art, it is a primary object to provide a function control method using short distance communication, and a terminal executing the same. 
     In accordance with an aspect of the present invention, a function control method of a terminal using short distance communication includes connecting with at least two secondary devices in a near distance mode and applying a key map to the connected secondary devices. When a key signal is received from at least one of the connected secondary devices, the method the secondary device from which the key signal is transmitted. And a function mapped to the key signal is executed according to the key map applied to the identified secondary device. 
     In accordance with another aspect of the present invention, a function control terminal includes a short distance communication unit for receiving a key signal from at least one of at least two connected secondary devices in a short distance communication mode. A controller applies a key map to the connected secondary devices, identifies the secondary device from which the key signal is transmitted when the key signal is received, and executes a function mapped to the key signal according to the key map applied to the checked secondary device. 
     Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts: 
         FIG. 1  illustrates a terminal and a secondary device connected by Bluetooth® communication according to the present disclosure; 
         FIG. 2  illustrates a system executing function control according to an embodiment of the present invention; 
         FIG. 3  illustrates a schematic configuration of a terminal according to an embodiment of the present invention; 
         FIG. 4  illustrates a schematic configuration of a secondary device according to an embodiment of the present invention; 
         FIG. 5  illustrates a protocol stack between a terminal and a secondary device according to an embodiment of the present invention; 
         FIG. 6  illustrates a signal flow for function control between a terminal and a secondary device according to an embodiment of the present invention; 
         FIG. 7  illustrates a function execution process in a terminal according to an embodiment of the present invention; 
         FIG. 8  illustrates a process for connecting with a plurality of secondary devices by a terminal according to an embodiment of the present invention; and 
         FIG. 9  illustrates a process for executing a function according to a key signal according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1 through 9 , discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged communication device. Detailed descriptions of well-known functions and structures incorporated herein may be omitted to avoid obscuring the subject matter of the present invention. 
     As used herein, the term “terminal” refers to an information-processing device that may generate or store data and exchange data with external devices. Here, the terminal can be a portable terminal, a computer, a note book computer, an MPEG Audio Layer-3 (MP3), or a Portable Multimedia Player (PMP), and may connect with other terminals using short distance communication such as Bluetooth® communication. The terminal is described assuming that it is the portable terminal. 
     As used herein, the “secondary device” refers to a device that may output data received from a terminal connected using short distance communication, and transmit a control signal selected by a user to the connected terminal. Here, the secondary device may become a headset, an earphone, a game remote controller, or another terminal. For illustrative purposes only, the present disclosure assumes that a secondary device is the headset. However, the present disclosure is not meant to limit the scope of secondary devices to a headset. 
       FIG. 2  illustrates a system executing function control according to an embodiment of the present invention. 
     Referring to  FIG. 2 , a terminal  100  may connect with a plurality of secondary devices. In detail, the terminal  100  executes a pairing with a first secondary device  200   a  to establish a connection. Next, the terminal  100  executes a pairing with a second secondary device  200   b  to establish a connection. The terminal  100  forms respective links to exchange data with the first and second secondary devices  200   a  and  200   b . In addition, the terminal  100  stores respective addresses of the first and second secondary devices  200   a  and  200   b . As illustrated above, the terminal  100  connecting with two secondary devices  200   a  and  200   b  executes functions according to control signals received from the first and second secondary devices  200   a  and  200   b , respectively. 
     As shown in  FIG. 2 , when the terminal  100  receives a command  210  requesting data from the first secondary device  200   a , it transmits an audio stream  215  according to the received command  210 . Meanwhile, when the terminal  100  receives a command  220  requesting data from the second secondary device  200   b , it transmits an audio stream  225  according to the received command  210 . At this time, the first secondary device  200   a  and the second secondary device  200   b  transmit respective commands  210  and  220  including unique identification information such as a user&#39;s address to the terminal  100 . Accordingly, the terminal  100  may compare respective addresses including the commands  210  and  220  with a stored address to discriminate the secondary device transmitting the command  210  or  220 . 
     A configuration of the terminal executing a function according to a key signal received from a plurality of secondary devices  200  is described with reference to  FIG. 3 . 
       FIG. 3  illustrates a schematic configuration of a terminal according to an embodiment of the present invention. 
     Referring to  FIG. 3 , the terminal  100  may include a short distance communication unit  310 , a storage unit  320 , a controller  330 , a display unit  340 , and an input unit  350 . The short distance communication unit  310 , the controller  330 , and the input unit  350  of the terminal  100  will also be referred as a first short distance communication unit  310 , a first controller  330 , and a first input unit  350  to distinguish from those of the secondary device  200 . 
     The first short distance communication unit  310  exchanges data with another device in a predetermined zone. Various wireless short distance communication modules such as a Bluetooth® module, a Zigbee module, an RFID module, and a WI-Fi module can be used as the first short distance communication unit  310 . Here, the Bluetooth® module can be used as the first short distance communication unit  310 . Furthermore, the first short distance communication unit  310  may exchange a key signal and data such as voices or images for controlling a function under the control of the first controller  330  with a secondary device  200  such as a headset, a hands-free, a game dedicated remote controller, or a portable terminal capable of performing Bluetooth® communication. 
     The storage unit  320  may store an application executed in the terminal  100  and all types of data. Here, the storage unit  320  stores a key map necessary for an application that may be executed in the terminal  100 . The key map includes information with respect to the number of keys necessary for each function executed in the application and information with respect to functions mapped to respective keys. 
     The first controller  330  executes a function for controlling states and operation of structural elements constituting the terminal  100 . The first controller  330  controls the first short distance communication unit  310  in a short distance communication mode to connect the terminal  100  with a plurality of secondary devices  200  according to user input. The first controller  330  may control the display unit  340  to display the types of a plurality of connected terminals  200 . Namely, the first controller  330  may display whether the connected secondary device  100  is a headset, an earphone, or a terminal to indicate what the connected secondary device  200  is to the user. Moreover, the first controller  330  may execute a function according to a key signal received from the plurality of secondary devices  200 . To do this, the first controller  330  should apply a key map to respective secondary devices  200  according to key information of the connected secondary device  200 . 
     When the first controller  330  calls a secondary device  200  to be connected according to the user selection, the first controller  330  checks whether there is another secondary device  200  connected to the terminal  100 . When another secondary device  200  is already connected to the terminal  100 , the first controller  330  displays an indication (e.g. using a pop-up window) that there is a previously connected secondary device  200 . The previously connected secondary device  200  refers to the first secondary device  200   a , and a next secondary device requesting to be connected refers to the second secondary device  200   b.    
     When multi-connection is selected to connect the terminal  100  with at least two secondary devices  200  according to the user selection, the first controller  330  connects with the second secondary device  200   b . At this time, the first controller  330  stores respective addresses received from the first secondary device  220   a  and the second secondary device  200   b  in the storage unit  320  or a buffer (not shown). In addition, the first controller  330  determines whether a currently executed application in the terminal  100  is an application supporting a multi-key. That is, the controller  330  checks whether the currently executed application is an application (such as a game) that is capable of simultaneously executing functions according to a plurality of key signals input from multiple users. 
     When the currently executed application is an application that supports a multi-key, the first controller  330  checks the key information of the first secondary device  200   a  and the key information of the second secondary device  200   b . The first controller  330  may also apply a key map by secondary devices  200  according to the checked key information. For example, the first secondary device  200   a  and the second secondary device  200   b  may be game-dedicated remote controllers, and a game application may be currently executed in the terminal  100 . Moreover, the first secondary device  200   a  may include nine keys (or buttons), and the second secondary device  200   b  may include five keys (or buttons) with arrow keys. In the following example, it is assumed that four keys are used to execute a game function in the game application. 
     Accordingly, the first controller  330  checks key information of a connected secondary terminal  200 . Furthermore, the first controller  330  applies a key map associated with each of the secondary devices  200   a  and  200   b  according to the checked key information. Namely, the first controller  330  applies a key map with respect to four keys necessary to execute a game function in the game application to respective secondary devices  200   a  and  200   b . Because the first secondary device  200   a  includes nine keys, the first controller  330  applies a key map to four of nine keys. Accordingly, the first controller  330  may disregard signals input from remaining keys except for the four keys to which the key map is applied in the first secondary device  200   a . In the second secondary device  200   b , the first controller  330  also applies a key map to four among five keys. Accordingly, the first controller  330  may disregard signals input from the remaining key except for the four keys to which the key map is applied in the second secondary device  200   b.    
     Here, this embodiment has been described such that the first controller  300  applies a key map using key information received from each secondary device  200 . However, the present invention is not limited thereto. That is, the first controller  330  may check types of respective secondary devices  200  and apply a corresponding key map according to a function to be executed in the respective secondary devices  200 . For example, it is assumed that the first secondary device  200   a  is a headset, a second secondary device  200   b  is a game dedicated remote controller, and a currently executed application is a game application. It is also assumed that the first secondary device  200   a  includes five keys, and the second secondary device  200   b  includes nine keys with arrow keys. Further, it is assumed that the game application utilizes five keys to execute a game function, and needs two keys to control sound data generated while a game application is running. 
     Accordingly, the first controller  330  checks types and key information of the first secondary device  200   a  and the second secondary device  200   b . The first secondary device  200   a  includes five keys and is a headset capable of outputting sound data. Accordingly, the first controller  330  checks the first secondary device  200   a  capable of outputting sound data generated during execution of a game function. Further, the first controller  330  applies a key map corresponding to the two keys for controlling the sound data to two among five keys included in the first secondary device  200   a . Accordingly, the first controller  330  may output sound data generated during execution of the game function through the first secondary device  200   a , and disregard signals input from remaining keys except for the two keys to which the key map is applied in the first secondary device  200   a.    
     Next, the first controller  330  checks a second secondary device  200   b  capable of controlling a game function. Then, the first controller  330  applies a key map to five of the nine keys included in the second secondary device  200   b  to control a game function. Accordingly, when executing a game function in the game application, the first controller  330  may disregard signals input from the remaining keys of the second secondary device  200   b  except for the five keys to which a key map is applied. 
     The first controller  330  displays information with respect to keys of the keys of the respective secondary devices  200   a  and  200   b  mapped to the key map and information with functions that can be executed through the keys on the display unit  340 . Accordingly, the user can look up the keys included in the respective secondary devices  200   a  and  200   b  to be used to control functions to be executed in the terminal  100 . 
     The first controller  300  may execute a corresponding function according to a key signal received from a plurality of connected secondary devices  200   a  and  200   b . In detail, when receiving the key signal, the first controller  330  identifies the secondary device  200  from which the signal has been received. The key signal includes an address of a secondary device  200  transmitting the key signal. Accordingly, the first controller  330  compares an address of the secondary device  200  included in the key signal with a stored address of the secondary device  200  to determine the secondary device  200  from which the key signal has been received. Moreover, the first controller  330  determines an appropriate function mapped to a key signal received through the key map applied to the secondary devices  200 . Next, the first controller  330  executes the appropriate function. 
     The display unit  340  may display a function or a menu executed in the terminal  100 . Moreover, the display unit  340  may use a Liquid Crystal Display (LCD). When the LCD is implemented by a touch screen, the display unit  340  can operate as the first unit  350 . The display unit  340  may display a multi-connection selection window capable of selecting a connection with a plurality of secondary devices  200  under the control of the first controller  330 . Moreover, the display unit  340  may display the types of the secondary devices connected through the multi-connection mode under the control of the controller  330 . 
     The first input unit  350  transfers numeral or character information input from a user and signals input associated with setting of respective functions and function control of the terminal  100  to the first controller  330 . The first input unit  350  can be implemented as a touch screen or a general key pad, and includes character keys in which numerals and characters are arranged, and function keys and soft keys to be selected such that a function can be executed. The first input unit  350  may include a Bluetooth® function key capable of selecting Bluetooth® communication. 
     The terminal  100  may further include various constructions according to executed functions therein. For example, the terminal  100  may further include an audio processing unit for receiving or outputting sound data, a digital broadcast-receiving unit for receiving digital broadcast data, and a wireless communication unit for performing a voice or video call. 
     A construction of a secondary device  200  that connects with the terminal  100  through short distance communication, transmits a control signal, or outputs data provided from the terminal  100  will be described with reference to  FIG. 4 . 
       FIG. 4  illustrates a schematic configuration of a secondary device according to an embodiment of the present invention. 
     Referring to  FIG. 4 , a secondary device  200  includes a short distance communication unit  410 , a controller  420 , and an input unit  430 . Hereinafter, structural elements of the secondary device  200  refer to a second short distance communication unit  410 , a second controller  420 , and a second input unit  430  to distinguish from those of the terminal  100 . 
     The second short distance communication unit  410  exchanges data with the terminal in a predetermined zone. Here, the second short distance communication unit  410  may transmit a key signal input through a wireless interface to the terminal  100  connected through short distance communication. Moreover, the second short distance communication unit  410  transmits all types of data received from the terminal  100  to the second controller  420 . 
     The second controller  420  controls states and operation of structural elements constituting the secondary device  200 . When a short distance communication mode is selected, the second controller  420  controls the second short distance communication unit  410  to connect with the terminal  100  that is requesting wireless connection. The second controller  420  controls the second short distance communication unit  410  to transmit an address allotted to the secondary device  200  and information with respect to a key included in the secondary device  200  to the terminal  100  requesting the wireless connection. The key information includes the number of keys in the secondary device  200  and information with respect to functions mapped to respective keys. 
     The second input unit  430  transfers signals associated with setting of respective functions input from a user and function control of the secondary device  200  to the second controller  420 . Assuming that the secondary device  100  is a headset, the second input unit  430  may include a volume key capable of adjusting a volume, a power key for turning on/off a power supply of the headset, and a call key for outputting voice data received from the terminal  100 . The second input unit  430  may also include a play/stop key, a forward key, and a rewind key, which are function keys for controlling multimedia play. 
     The second input unit  430  transfers signals associated with setting control of respective functions input from a user to the second controller  420 . For example, when the secondary device  200  is a headset, the second input unit  430  may include a volume key capable of adjusting a volume, a power key for turning on/off a power supply of the headset, and a call key for outputting voice data received from the terminal  100 . The second input unit  430  may include a play/stop key, a forward key, and a rewind key, which are function keys for controlling multimedia play. 
     Although not shown in the drawings, the secondary device  200  may further include an audio processing unit for exchanging voice data with the terminal  100  according to a function to be executed, and a display unit for displaying the data exchanging with the terminal  100 . 
     This embodiment has described constructions of the terminal  100  and the secondary device  200  that are connected to each other through short distance communication. The following is a description of a protocol stack when short distance communication connection is achieved between the terminal  100  and the secondary device  200  with reference to  FIG. 5 . Here, the secondary device  200  is described assuming that it is a headset capable of outputting voice data and transmitting a control signal. 
       FIG. 5  illustrates a protocol stack between a terminal and a secondary device according to an embodiment of the present invention. 
     The protocol stack between the terminal  100  and the secondary device  200  can be configured by first layers  510   a ,  510   b , and  510   c  composed of a baseband; second layers  520   a ,  520   b , and  520   c  composed of a Link Manager Protocol (LMP) and a Logical Link Control and Adaptation Protocol (L2CAP); third layers  530   a ,  530   b , and  530   c  composed of Audio/Video Control Transport Protocol (AVCTP) and a Service Discovery Protocol (SDP); fourth layers  540   a ,  540   b , and  540   c  composed of an audio/video (AV) control protocol; and fifth layers  550   a ,  550   b , and  550   c  composed of an application executed by the terminal  100  or the secondary device  200 . The terminal  100  further includes a sixth layer  560   c  composed of a key emulator protocol and a seventh protocol  570   c  composed of a multi-key support application and a single key support application. 
     The first layers  510   a ,  510   b , and  510   c  enable a physical RF link between Bluetooth® units (for example, the terminal  100  and the secondary devices  200   a  and  200   b ), forming a Pico-net. The LMP constituting the second layers  520   a ,  520   b , and  520   c  is a protocol processing link establishment which forms an Asynchronous Connectionless Link (ACL Link) for exchanging control signals between the terminal  100  and the secondary device  200 , and a Synchronous Connection Oriented Link (SCO Link) capable of exchanging various data such as voice data and image data. Meanwhile, L2CAP is a transport protocol that enables transport of up to 64 kilobytes (Kb) of user data with respect to an upper layer protocol and an application. 
     An SDP among protocols constituting the third layers  530   a ,  530   b , and  530   c  is a protocol that processes setting and discovery of services in an upper stack of Bluetooth®. An AVCTP is a protocol for controlling transmission of audio and video data. 
     The fourth layers  540   a ,  540   b , and  540   c  are configured by profiles controlling transmitted or received audio and video data. An application constituting the fifth layers  560   a ,  560   b , and  560   c  is achieved by an application executed through Bluetooth® communication. 
     The sixth layer  560   c  of the terminal  100  is configured by a protocol for applying a key map according to key information of the first secondary device  200   a  and the second secondary device  200   b  connected to the terminal  100 . The seventh layer  570   c  is composed of a multi-key support application and a single key support application that can be executed in the terminal  100 . 
     In the present invention, the L2CAP of the second layers  520   a ,  520   b , and  520   c  supports one Protocol/Service Multiplexer (PSM), and may discriminate a key signal provided from the respective secondary devices  200   a  and  200   b  in the application of the fifth layers  560   a ,  560   b , and  560   c  through addresses of the respective secondary devices  200   a  and  200   b . The key signals provided from the respective secondary devices  200   a  and  200   b  are converted into a key event applied to a current application through a key emulator of the sixth layer  560   c  included in the terminal  100 . 
     Signal flow for performing function control between the terminal  100  and the secondary device  200  connected through a protocol stack will be described in detail with reference to  FIG. 6 . 
       FIG. 6  illustrates a signal flow for function control between a terminal and a secondary device according to an embodiment of the present invention. 
     Referring to  FIG. 6 , a terminal  100  connects with the first secondary device  200   a  ( 610   a ) and connects with the second secondary device  200   b  ( 610   b ). At this time, the terminal  100  connects with the first secondary device selected by a user through pairing. The terminal  100  connects with a next selected secondary device through pairing. The terminal  100  also forms links for exchanging data with respective secondary devices  200   a  and  200   b . The terminal  100  may store respective addresses provided from respective secondary devices  200   a  and  200   b . Moreover, the terminal  100  checks key information provided from the respective secondary devices  200   a  and  200   b , and applies an appropriate key map to the respective secondary devices  200   a  and  200   b  according to the checked key information. 
     When a key signal from the first secondary device  200   a  is transmitted ( 620 ), the terminal  100  identifies which secondary device  200  transmitted the key signal ( 625 ). Next, the terminal  100  transmits a response signal to the first secondary checked terminal  200   a  ( 630 ). In an embodiment, the terminal  100  may compare an address of the secondary device included in the key signal with a stored address to verify that the secondary device that transmitted the key signal. 
     Then, the terminal  100  executes a function according to the key signal ( 635 ). In an embodiment, the terminal  100  checks a key map applied to the first secondary device  200   a  and determines the function mapped to a received key signal from the checked key map. Subsequently, the terminal  100  executes the checked function. 
     When the second secondary device  200   b  transmits a key signal ( 640 ), the terminal  100  determines which secondary device transmitted the key signal ( 645 ). Next, the terminal  100  transmits a response signal to the second secondary checked terminal  200   b  ( 650 ). At this time, the terminal  100  may also compare an address of the secondary device included in the key signal with a stored address to verify the secondary device that transmitted the key signal. Next, the terminal  100  executes a function according to the key signal ( 655 ). In detail, the terminal  100  checks a key map applied to the second secondary device  200   a  and determines the function mapped to a received key signal from the checked key map. Subsequently, the terminal  100  executes the checked function. 
     A process for connecting with a plurality of secondary devices  200  and executing a function according to a key signal provided from the plurality of secondary devices  200   a  and  200   b  by the terminal  100  will be explained with reference to  FIG. 7  to  FIG. 9 . 
       FIG. 7  illustrates a function execution process in a terminal according to an embodiment of the present invention. 
     Referring to  FIG. 7 , a terminal  100  executes a short distance communication mode according to user selection (block  710 ). The terminal  100  checks whether connection of a secondary device is selected (block  715 ). In and embodiment, the terminal  100  detects a secondary device  200  among secondary devices located around the terminal  100  capable of performing short distance communication. Moreover, the terminal  100  displays the secondary device  200  capable of performing short distance communication. Next, the terminal  100  checks whether there is a secondary device  200  selected from among the secondary devices. 
     When the connection of the secondary device is selected, the terminal  100  checks whether there is a secondary device  200   a  that is already connected to the terminal (block  720 ). When there is no previously connected secondary device, the terminal  100  executes connection of the secondary device (block  730 ). In block  735 , the terminal  100  may transmit data to the connected secondary connected terminal or execute a function according to a key signal received from the secondary device  200 . 
     Alternatively, when the first secondary device  200  is already connected to the terminal  100 , the terminal  100  displays a multi-connection selection window (block  740 ). Next, the terminal  100  determines whether multi-connection mode is selected (block  745 ). When the multi-connection mode is selected, the terminal  100  maintains the connection with the first secondary device  200   a  previously connected, and establishes a multi-connection by additionally connecting to the second secondary device  200   b  (block  750 ). 
     Block  750  will be described later with reference to  FIG. 8 . After establishing the multi-connection, the terminal  100  executes functions according to key signals provided from a plurality of secondary devices  200  (block  760 ). Block  760  will be described later with reference to  FIG. 9 . 
     Alternatively, when multi-connection mode is not selected at block  745 , the terminal  100  indicates to the user that connection of a plurality of secondary devices  200  is not permitted (block  770 ). Although not shown in drawings, the terminal  100  checks whether short distance communication mode termination is selected. When the short distance communication mode termination is selected, the terminal  100  cancels the connection with all secondary devices  200 . When termination of the short distance communication mode is selected, the terminal  100  executes a function according to a key signal provided from the secondary connected terminal  200 . The terminal  100  may determine whether connection of another secondary device  200  is selected, and connect with a plurality of secondary devices  200 . 
     A multi-connection process referred in block  740  of  FIG. 7  is described with reference to  FIG. 8 . 
       FIG. 8  illustrates a process for connecting with a plurality of secondary devices by a terminal according to an embodiment of the present invention. 
     Referring to  FIG. 8 , when the multi-connection mode is selected, the terminal  100  performs pairing with a selected secondary device  200   b . In block  810 , the terminal  100  may form a link for exchanging data with the second secondary device  200   b . In block  820 , the terminal  100  detects the presence of multi-key support of an application currently executed in the terminal  100 . When the executed application supports a multi-key, the terminal  100  checks key information of the first secondary device  200   a  and the second secondary device  200   b  (block  830 ). The terminal  100  may determine the device type of the first secondary device  200   a  and the second secondary device  200   b . That is, the terminal  100  may determine whether each of the connected secondary devices is a headset, a game dedicated remote controller, or a terminal. 
     In block  835 , the terminal  100  applies an appropriate key map according to the checked key information for each of the first secondary device  200   a  and the second secondary device  200   b . In addition, the terminal  100  may apply a key map based on the device type of the first secondary device  200   a  and the second secondary device  200   b . For example, when the first secondary device  200   a  is a headset, the second secondary device  200   b  is a game dedicated remote controller, and a currently executed application is a game application, the terminal  100  applies a key map for controlling voice data generated during execution of a game function to the first secondary device  200   a , and applies a key map for controlling a game function to the second secondary device  200   b . Here, a game application may be a representative example of applications capable of supporting a multi-key. The multi-key support application refers to an application that may concurrently execute functions according to key signals received from multiple secondary devices. 
     Alternatively, when the application does not support a multi-key, the terminal  100  checks key information of the first secondary device  200   a  and the second secondary device  200   b  (block  840 ). In block  845 , the terminal  100  applies the same key map to the first secondary device  200   a  and the second secondary device  200   b  (block  845 ). Here, an MP3 application may be a representative example of an application that does not support the multi-key. Namely, the application that does not support the multi-key refers to an application capable of executing functions according to a key signal received from a single secondary device at one time. 
     Block  760  of  FIG. 7 , which is a process for executing a function according to a key signal received from the secondary device  200  by the terminal  100 , is explained in detail with reference to  FIG. 9 . 
       FIG. 9  illustrates a process for executing a function according to a key signal according to an embodiment of the present invention. 
     Referring to  FIG. 9 , a terminal  100  checks whether a key signal is received through a link formed between the terminal  100  and respective secondary devices  200  (block  910 ). When the key signal is received, the terminal  100  identifies the secondary device  200  that transmitted the received key signal (block  920 ). At this time, the terminal  100  may verify the secondary device  200  that transmitted the key signal based on an address of the secondary device  200  included in the key signal. 
     In block  930 , the terminal  100  checks a key map applied to the identified secondary device  200 . In block  940 , the terminal  100  determines which function is mapped to the key signal received from the secondary device  200  based on the checked key map. In block  950 , the terminal  100  executes the determined function (block  950 ). 
     Through the foregoing processes, the terminal  100  such as a portable terminal can connect with multiple secondary devices and may execute functions according to key signals provided from the plurality of secondary devices. Through this, multiple users can use various functions using one terminal  100 . 
     In other words, when an application such as an MP3 application is capable of executing one function at one time, the same key map is applied to respective secondary devices  200   a  and  200   b , such that the respective secondary devices  200   a  and  200   b  can connect with the terminal  100 . When an application such as a game application is capable of simultaneously executing functions according to a plurality of key inputs, respective key maps are applied to the secondary devices  200   a  and  200   b , such that the secondary devices  200   a  and  200   b  can connect with the terminal  100 . Accordingly, the terminal  100  may execute corresponding functions according to key signals received from the respective secondary devices  200   a  and  200   b.    
     In the present invention, one terminal may connect with a plurality of secondary devices. Moreover, the terminal may recognize control signals received from a plurality of secondary devices to execute functions accordingly. Accordingly, a user may share one terminal with plural users to use various functions such as a game. 
     Although the present disclosure has been described with an exemplary embodiment, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.