Patent Description:
PTL <NUM> discloses a game machine that includes a plurality of communication modules of the same type that wirelessly communicate by a frequency hopping method. A control unit of the game machine determines a hopping frequency channel of at least one communication module such that frequency channels used by a plurality of communication modules may not overlap with each other in time.

[PTL <NUM>]
<CIT>. Other previously proposed arrangements are disclosed in <CIT>.

A contrivance that allows users to play a game together while doing voice chat has been proposed. The users are released from the troublesomeness of a cable by using a wireless headset. Further, by incorporating a microphone and a speaker in a wireless game controller for operating a game machine, an environment in which a user can enjoy voice chat without a headset is implemented. By emergence of such electronic apparatus, it is necessary for a game machine to be capable of transmitting and receiving a large amount of data to and from an electronic apparatus and it is necessary to construct a contrivance that manages wireless connection efficiently in the case where a plurality of electronic apparatuses are connected simultaneously.

The object of the present invention resides in provision of a technology relating to a wireless communication device.

In order to solve, or at least alleviate, or at least address, the subject described above, according to an example mode of the present invention, there is provided a communication device that includes a first communication unit, and a second communication unit of a type same as that of the first communication unit, and that is wirelessly connected (or at least connectable) to an external apparatus, in which the first communication unit has a function for waiting for a connection request from external apparatus and the second communication unit is wirelessly connected to an external apparatus from which the first communication unit receives a connection request.

According to another example mode of the present invention, there is provided an electronic apparatus that is wirelessly connected to a communication device that includes a plurality of communication units of the same type, including a retaining unit that retains identification information of one of the communication units acquired by a pairing process with the communication unit, and a connection processing unit that transmits a connection request including the identification information of the one communication unit.

According to a further example mode of the present invention, there is provided a wireless connection method for establishing wireless connection to a communication device that includes a plurality of communication units of the same type, including a step of retaining identification information of one of the communication units acquired by a pairing process with the communication unit, and a step of transmitting a connection request including the identification information of the one communication unit.

It is to be noted that also an arbitrary combination of the components described above and representations of the present invention, which are converted among a method, a device, a system, a computer program, a recording medium on which the computer program is readably recorded, a data structure and so forth, are effective as modes of the present invention.

In the following, a communication system of an embodiment is described. The communication system of the embodiment includes a communication device and at least one electronic apparatus. The communication device and the electronic apparatus wirelessly communicate with each other using the Bluetooth (Bluetooth, registered trademark) protocol that adopts a frequency hopping method. In the case where the communication device is incorporated in a game device, the electronic apparatus that is wirelessly connected to the communication device may be a game device peripheral such as a headset or a game controller that allows a user to perform voice chat. By incorporating the functions of a microphone and a speaker into a game controller, a user can carry out voice chat even without a headset.

The communication device of the embodiment includes a plurality of communication units (transceivers) of the same type. Here, the "same type" may indicate for example that the physical circuitry of the communication units is identical or is at least capable of identical or similar function. It may indicate for example that operating software and/or operating protocols of the communication units are identical. It implies that (a) the communication units can operate according to the same wireless communications protocol(s) (such as, though not exclusively, a Bluetooth ® protocol). This allows wireless communications with any given external apparatus to be handled interchangeably by either or any of the communications units.

So, the communications process by the external apparatus is the same or similar, independent of which communications unit forms the other party to such communication such that the external apparatus is equally capable of communication with any of a plurality of such communication units of the same type, for example, by following a common communications protocol in its communication with the communication units of the same type. (Having said this, it is of course noted that there may be aspects of communication with a particular communication unit which are specific to that particular communication operation with that particular communication unit. For example, the communication between the external device and the particular communication unit may potentially specify an identifier (whether paired or on an ad-hoc basis) of that particular communication unit, or the external apparatus and communication unit may each operate selectively as a master or a slave for that specific communication operation, or the actual data transmitted or received during the particular communication may be specific to the particular communication).

In this way, by providing a plurality of communication units of the same type, the communication device can increase the communication capacity and can wirelessly communicate with many electronic apparatus. The plurality of communication units may be controlled by a single device driver, and data from the plurality of communication units may be handled as data from a single communication unit by the device driver. The device driver connects the communication units and the electronic apparatus suitably on the basis of communication situations of the plurality of communication units. It is to be noted that the communication device of the embodiment may be incorporated in an information processing device of a different type other than a game device.

<FIG> depicts a communication system <NUM> of the embodiment. A communication device <NUM> includes a device main body <NUM> and a communication block <NUM>. The communication block <NUM> includes a plurality of Bluetooth (this may be hereinafter referred to simply as "BT") communication apparatus. The device main body <NUM> includes a device driver that controls the communication block <NUM>, and data acquired via the communication block <NUM> is supplied to application software of a game or chat. Electronic apparatuses 200a to 200d (in the case where they are not distinguished from each other, each of them is referred to as "electronic apparatus <NUM>") may be a peripheral such as a headset or a game controller that includes a BT communication apparatus.

Note that the present techniques are not restricted to BT arrangements. Other communications protocols, such as other frequency-hopping protocols (for example non-BT protocols using adaptive frequency hopping spread spectrum or frequency hopping code division multiple access techniques) may be used instead or in addition. The term "communications operations" refers to the use of any such techniques.

The communication block <NUM> is wirelessly connected to one or more electronic apparatus <NUM>. The device driver incorporated in the device main body <NUM> efficiently allocates an electronic apparatus <NUM> to one of the plurality of communication units of the communication block <NUM> and supports good wireless communication between the communication block <NUM> and the electronic apparatus <NUM>.

The communication device <NUM> may comprise a programmable processing unit and therefore provides an example of a computer provided in a communication device that includes a plurality of communication units of the same type. The computer (such as that shown schematically in <FIG>) can, under the control of a program comprising computer-executable instructions, perform any of the methods or techniques discussed here relating to the operations of such a communication device.

The electronic apparatus <NUM> may comprise a programmable processing unit and therefore provides an example of a computer which is wirelessly connectable to a communication device that includes a plurality of communication units of the same type. The computer (such as that shown schematically in <FIG>) can, under the control of a program comprising computer-executable instructions, perform any of the methods or techniques discussed here relating to the operations of such an electronic apparatus.

<FIG> is a block diagram of part of the communication device <NUM> that is wirelessly connected to an external electronic apparatus. The communication device <NUM> includes a power supply block <NUM>, a system controller <NUM>, a host block <NUM>, and a communication block <NUM>. In the power supply block <NUM>, a VDD_MAIN <NUM> supplies main power, and a VDD_LP <NUM> supplies low power. In the example depicted in <FIG>, the system controller <NUM> and the communication block <NUM> are driven by the low power supply and the host block <NUM> is drive by the main power supply.

The communication block <NUM> includes a plurality of communication units of the same type and includes, in the embodiment, two communication units of a first communication unit <NUM> and a second communication unit <NUM>. That the communication units are of the same type may signify that communication standards used by them are same as each other. The communication block <NUM> may be configured as a system-on-chip and the first communication unit <NUM> and the second communication unit <NUM> may operate on the basis of a clock signal of a common system clock oscillator provided on the same chip. The first communication unit <NUM> and the second communication unit <NUM> are integrated circuit parts that are individually connected to antennae and have a function for establishing wireless connection to an external electronic apparatus <NUM> in accordance with the Bluetooth protocol. A universal serial bus (USB) module <NUM> of the host block <NUM> and a USB module <NUM> of the communication block <NUM> are connected to each other in accordance with a common USB standard. It is to be noted that the host block <NUM> and the communication block <NUM> may be connected to each other in accordance with a communication standard other than the USB standard.

The first communication unit <NUM> and the second communication unit <NUM> are connected to the single USB module <NUM>. By commonly using the single USB module <NUM> in the communication block <NUM>, the chip production cost of the communication block <NUM> can be reduced. A data signal received by the first communication unit <NUM> and/or the second communication unit <NUM> is transmitted to the USB module <NUM> through the USB module <NUM> and is subjected to necessary processing by a control unit <NUM> and then provided to a main central processing unit (CPU) (not depicted) that executes an application. Meanwhile, a data signal generated by the main CPU is transmitted to the USB module <NUM> through the USB module <NUM> and is transmitted from the first communication unit <NUM> or the second communication unit <NUM> to the electronic apparatus <NUM> to which the first communication unit <NUM> or the second communication unit <NUM> is wirelessly connected.

In the following, a state transition of a power supply system in the communication device <NUM> is described.

In the case where the power supply cable of the communication device <NUM> is not connected to an electrical outlet, the communication device <NUM> is in a power off state.

If the power supply cable of the communication device <NUM> is connected to the electrical outlet, then the system controller <NUM> is started. After the system controller <NUM> is started, it supplies power to the host block <NUM> and the communication block <NUM>. After the host block <NUM> is started, the system controller <NUM> supplies a USB_EN signal for enabling the USB module <NUM> to the communication block <NUM>. Consequently, the USB module <NUM> and the USB module <NUM> are USB connected to each other.

In the host block <NUM>, the control unit <NUM> operates as a device driver that controls a BT communication apparatus. The control unit <NUM> downloads firmware to the first communication unit <NUM> through the USB connection to initialize the first communication unit <NUM>. In this state, the control unit <NUM> carries out initialization only of one communication unit, namely, the first communication unit <NUM>, determined in advance from among the plurality of communication units of the same type and does not perform initialization of the second communication unit <NUM>. The control unit <NUM> sets parameters for wake on to the first communication unit <NUM>.

After the control unit <NUM> sets the parameters for wake on to the first communication unit <NUM>, the system controller <NUM> stops the power supply to the host block <NUM> and stops supply of the USB_EN signal. Consequently, in the communication device <NUM>, only the system controller <NUM> and the first communication unit <NUM> maintain the started state.

The first communication unit <NUM> enters a page scan mode for waiting for a connection request from an external electronic apparatus <NUM>. The first communication unit <NUM> has acquired and retained address information (apparatus identification (ID)) for identifying electronic apparatus <NUM> to be connected to the communication device <NUM> by a pairing process in advance. The first communication unit <NUM> may have acquired and retained address information by predetermined pairing information being encoded in one or both of the electronic apparatus and the communications device, or by using an ad-hoc association between the electronic apparatus and the communications device. The first communication unit <NUM> reads out, in the page scan mode, a connectable apparatus ID list which includes one or more apparatus IDs and waits for a connection request (paging) from an electronic apparatus <NUM>. In the state of the wake on BT, a connection request from an external electronic apparatus <NUM> becomes a starting request for the entire communication device including the device main body <NUM>.

If the first communication unit <NUM> receives a connection request from an electronic apparatus <NUM> having a BT device address included in the apparatus ID list, then it outputs a WAKE signal to the system controller <NUM> in accordance with the parameters for wake on. When the system controller <NUM> receives the WAKE signal, it supplies power to the host block <NUM> and supplies a USB_EN signal for enabling the USB module <NUM> to the communication block <NUM>. The control unit <NUM> downloads firmware to the second communication unit <NUM> through the USB connection to initialize the second communication unit <NUM>. Consequently, in the communication block <NUM>, the first communication unit <NUM> and the second communication unit <NUM> are placed into a state in which they can establish wireless connection to the external electronic apparatus <NUM>.

In a suspend state, the first communication unit <NUM> operates in a page scan mode for waiting for a connection request from an external electronic apparatus <NUM>. The USB module <NUM> and the USB module <NUM> suspend and the second communication unit <NUM> sleeps.

<FIG> depicts a configuration relating to communication between the communication device <NUM> and an electronic apparatus <NUM>. The control unit <NUM> functions as a device driver for controlling the first communication unit <NUM> and the second communication unit <NUM>. The control unit <NUM> includes a connection management unit <NUM>, an allocation processing unit <NUM>, and a role management unit <NUM>. Any one or more of these may be considered as a "control unit" in the context of the discussions below.

The first communication unit <NUM> has a function for wirelessly communicating with an external apparatus by the Bluetooth protocol and includes a connection processing unit <NUM>, a communication controlling unit <NUM>, a retaining unit <NUM>, and a clock counter <NUM>. The connection processing unit <NUM> executes a process for establishing wireless connection to an electronic apparatus <NUM>. The communication controlling unit <NUM> transmits and receives a data signal to and from the electronic apparatus <NUM> after establishment of the connection. The clock counter <NUM> generates a BT clock of <NUM> bits whose clock rate is <NUM>. The retaining unit <NUM> retains apparatus ID information of electronic apparatus <NUM> with which a pairing process was performed in the past, and the connection processing unit <NUM> has a function for waiting for a connection request from an external electronic apparatus <NUM>.

The second communication unit <NUM> has a function for wirelessly communicating with an external apparatus by the Bluetooth protocol and includes a connection processing unit <NUM>, a communication controlling unit <NUM>, and a clock counter <NUM>. The connection processing unit <NUM> executes a process for establishing wireless connection to an electronic apparatus <NUM> from which a connection request is received by the first communication unit <NUM>. The communication controlling unit <NUM> transmits and receives a data signal to and from the electronic apparatus <NUM> after establishment of the connection. The clock counter <NUM> generates a BT clock of <NUM> bits whose clock rate is <NUM>. In the communication device <NUM> of the embodiment, the value of a predetermined bit of the BT clock of the clock counter <NUM> and the value of the predetermined bit of the BT clock of the clock counter <NUM> are controlled so as to synchronize with each other. Different from the connection processing unit <NUM>, the connection processing unit <NUM> in the embodiment does not have a function for waiting for a connection request from an external electronic apparatus <NUM> and does not wait for a connection request. It is to be noted that, although, in a different example, the connection processing unit <NUM> may have a function for waiting for a connection request, it is desirable to restrict the waiting function such that the connection processing unit <NUM> does not wait for a connection request.

The electronic apparatus <NUM> wirelessly connects to the first communication unit <NUM> and/or the second communication unit <NUM> by the Bluetooth protocol. The electronic apparatus <NUM> includes a connection processing unit <NUM>, a communication controlling unit <NUM>, a retaining unit <NUM>, and a clock counter <NUM>, and the connection processing unit <NUM> includes a connection requesting unit <NUM>, an instruction processing unit <NUM>, and a request processing unit <NUM>. The retaining unit <NUM> retains apparatus ID information of the first communication unit <NUM> acquired by a pairing process with the communication device <NUM>.

Referring to <FIG>, components described as functioning blocks that perform various processes can be configured, in hardware, from a circuit block, a memory, and other large scale integrations (LSIs) and is implemented, in software, from system software, a game program loaded in the memory and so forth. Accordingly, it is recognized by those skilled in the art that the functioning blocks can be implemented in various forms only from hardware, only from software, or from a combination of them and are not restrictive.

In the following, a procedure for establishing wireless connecting between an electronic apparatus <NUM> and the communication device <NUM> is described.

In order to wirelessly connect to the communication device <NUM>, the electronic apparatus 200carried out a pairing process with the communication device <NUM> in advance. In the pairing process, the electronic apparatus <NUM> and the first communication unit <NUM> exchanged mutual apparatus ID information. Therefore, in the retaining unit <NUM> of the electronic apparatus <NUM>, the apparatus ID information of the first communication unit <NUM> has been retained, and in the retaining unit <NUM> of the first communication unit <NUM>, the apparatus ID information of the electronic apparatus <NUM> has been retained. As the first communication unit <NUM> has performed the pairing process with a plurality of electronic apparatuses 200a to 200d to which the first communication unit <NUM> is wirelessly connectable, the apparatus ID information of the plurality of electronic apparatuses 200a to 200d has been retained into the retaining unit <NUM> to generate an apparatus ID list.

The communication device <NUM> is in a wake on BT state when it has no wireless connection to any electronic apparatus <NUM>.

<FIG> depicts a sequence by which the electronic apparatus <NUM> and the communication device <NUM> establish wireless connection to each other. In the wake on BT state, the first communication unit <NUM> operates in a page scan mode in which it waits for a connection request from an external electronic apparatus <NUM> (S10). In the page scan mode, the connection processing unit <NUM> of the first communication unit <NUM> waits for a connection request (paging) from an electronic apparatus <NUM> included in the connectable apparatus ID list.

In the electronic apparatus <NUM>, the connection requesting unit <NUM> reads out the apparatus ID information of the first communication unit <NUM> from the retaining unit <NUM> and transmits a connection request including the apparatus ID information of the first communication unit <NUM> to the first communication unit <NUM> (S12). In the first communication unit <NUM>, when the connection processing unit <NUM> receives the connection request from the electronic apparatus <NUM> having a device ID included in the apparatus ID list, it outputs a WAKE signal to the system controller <NUM> in accordance with the wake on parameters (S14). When the system controller <NUM> receives the WAKE signal, it starts up the host block <NUM> and the USB module <NUM> to make the USB connection between the USB module <NUM> and the USB module <NUM> active.

In the control unit <NUM>, the connection management unit <NUM> downloads firmware into the second communication unit <NUM> through the USB connection to initialize the second communication unit <NUM>. Consequently, the second communication unit <NUM> is placed into a wirelessly connectable state to an external electronic apparatus <NUM> (S16). The connection management unit <NUM> executes an authentication process and an encryption process with the electronic apparatus <NUM>, and the first communication unit <NUM> establishes connection to the electronic apparatus <NUM> in an active mode that is a data transfer mode in which it is possible to transfer data (S18).

A BT communication apparatus operates as one of a master and a slave. (In some examples, a particular BT communication apparatus may be constrained by design or by configuration setting to operate at any point in time as either a master or a slave, which is to say that in such examples the BT communication apparatus cannot operate simultaneously as both a master and a slave even with different communication destinations). If two BT communication apparatus establish a BT link therebetween on the base band level, then the paging device becomes the master and the paged device becomes the slave. The master determines a frequency hopping pattern on the basis of an own BT device address and determines a phase of a hopping sequence by an own clock.

At the point of time of S18, the electronic apparatus <NUM> that is the paging device is the master, and the first communication unit <NUM> that is the paged device is the slave. In order for the communication device <NUM> to control the electronic apparatus <NUM> that is a peripheral, it is necessary for the first communication unit <NUM> and the electronic apparatus <NUM> to operate as the master and the slave, respectively, the role management unit <NUM> transmits a role switching instruction for switching the roles (roles) of the master and the slave to the electronic apparatus <NUM> through the first communication unit <NUM> (S20). In the electronic apparatus <NUM>, the instruction processing unit <NUM> accepts the role switching instruction. The connection processing unit <NUM> in the first communication unit <NUM> and the instruction processing unit <NUM> execute switching of the roles in synchronism with each other after a predetermined interval of time after the role switching instruction is transmitted. Consequently, the electronic apparatus <NUM> starts operation as the slave and the first communication unit <NUM> starts operation as the master.

In the communication system <NUM> of the embodiment, after the first communication unit <NUM> accepts a connection request from an electronic apparatus <NUM> and establishes wireless connection to the electronic apparatus <NUM>, it instructs the electronic apparatus <NUM> to establish a state in which the electronic apparatus <NUM> waits for acceptance of a connection request (S22). This is a process necessary to switch the connection destination of the electronic apparatus <NUM> (from which the connection request was received) from the first communication unit <NUM> to the second communication unit <NUM>, and such switching occurs in response to receipt of the connection request as well as in dependence upon an allocation process. In the following, a reason why the first communication unit <NUM> transmits a waiting instruction to the electronic apparatus <NUM> is described.

The connection management unit <NUM> acquires a communication situation (or communication status) of the first communication unit <NUM> with an external apparatus and a communication situation (or communication status) of the second communication unit <NUM> with an external apparatus. At the point of time of establishment of connection at S18, the first communication unit <NUM> is connected to one electronic apparatus <NUM> and the second communication unit <NUM> is not connected to any electronic apparatus <NUM>. The connection management unit <NUM> may acquire the numbers of external apparatus to which the first communication unit <NUM> and the second communication unit <NUM> are connected individually as the communication situations.

The allocation processing unit <NUM> executes an allocation process for determining the connection destination of the external apparatus to the first communication unit <NUM> or the second communication unit <NUM> on the basis of the communication situations acquired by the connection management unit <NUM> of the first communication unit <NUM> and the second communication unit <NUM>. Here, while the first communication unit <NUM> has the function for waiting for a connection request from an external apparatus, the second communication unit <NUM> does not have the function or does not execute the function for waiting for a connection request from an external apparatus. Since the first communication unit <NUM> in the embodiment has a role of periodically operating in the page scan mode, the allocation processing unit <NUM> preferably determines the connection destination of the external apparatus to the first communication unit <NUM> or the second communication unit <NUM> such that the communication load with the external apparatus on the first communication unit <NUM> is equal to or lower than the communication load with the external apparatus on the second communication unit <NUM>. Therefore, when only one electronic apparatus <NUM> is connected to the communication device <NUM>, preferably the allocation processing unit <NUM> determines the connection destination of the electronic apparatus <NUM> to the second communication unit <NUM> to make the communication load on the first communication unit <NUM> lighter than the communication load on the second communication unit <NUM>.

The communication load to be used as a reference for decision of an allocation destination by the allocation processing unit <NUM> is a load factor having an influence on communication by each communication unit and may be the number of external apparatus to which each communication unit is connected. Therefore, the allocation processing unit <NUM> may allocate an external apparatus to the first communication unit <NUM> or the second communication unit <NUM> such that the number of external apparatus to which the first communication unit <NUM> is connected is smaller than the number of external apparatus to which the second communication unit <NUM> is connected.

It is to be noted that the communication load to be used as a reference may be a communication data amount of each communication unit with an external apparatus. Although the data amount of voice data in voice chat with an electronic apparatus <NUM> is great, the data amount of operation data of a game controller is small. Therefore, the connection management unit <NUM> may monitor the communication data amount between each communication unit and an electronic apparatus <NUM>, and the allocation processing unit <NUM> may determine the connection destination of the electronic apparatus <NUM> such that the communication load on the first communication unit <NUM> becomes lower than the communication load upon the second communication unit <NUM>. The communication load to be used as a reference may be a communication error rate in each communication unit or may be a combination of some of them.

At the point of time of establishment of connection at S18, only one electronic apparatus <NUM> is already connected to the communication device <NUM>. Therefore, the allocation processing unit <NUM> determines to change the connection destination of the electronic apparatus <NUM> from the first communication unit <NUM> to the second communication unit <NUM>. In the communication system <NUM> of the embodiment, in order to change the connection destination, the allocation processing unit <NUM> initiates a connection process of the already connected electronic apparatus to the second communication device. To do this, the electronic apparatus <NUM> is caused to operate in a scan mode (such as the page scan mode) and the second communication unit <NUM> is caused to transmit a connection request to the electronic apparatus <NUM>. To this end, at S22, the first communication unit <NUM> transmits a signal (waiting instruction signal) for instructing the electronic apparatus <NUM> to establish a state in which the electronic apparatus <NUM> waits for a connection request from the second communication unit <NUM>.

In this connection destination switching process, the allocation processing unit <NUM> notifies the first communication unit <NUM> and the second communication unit <NUM> that the connection destination of the electronic apparatus <NUM> currently connected to the first communication unit <NUM> is to be switched from the first communication unit <NUM> to the second communication unit <NUM>. At this time, the allocation processing unit <NUM> notifies the first communication unit <NUM> and the second communication unit <NUM> also of apparatus ID information (BT device address) of the electronic apparatus <NUM> to which the connection destination is to be changed. Consequently, the first communication unit <NUM> and the second communication unit <NUM> recognize that they are to operate such that the electronic apparatus <NUM> currently connected to the first communication unit <NUM> is connected to the second communication unit <NUM>.

In the first communication unit <NUM>, the connection processing unit <NUM> transmits a waiting instruction signal to the electronic apparatus <NUM> (S22). The waiting instruction signal may include identification information of an apparatus (for example, communication unit) from which a connection request is to be transmitted, in the present example, apparatus ID information of the second communication unit <NUM>. In the electronic apparatus <NUM>, the instruction processing unit <NUM> receives a waiting instruction signal and accepts an instruction to enter a state in which it waits for a connection request from the second communication unit <NUM>. Consequently, while the instruction processing unit <NUM> maintains the connection to the first communication unit <NUM>, the request processing unit <NUM> operates in the page scan mode for waiting for a connection request from the second communication unit <NUM> (S24).

At this time, the instruction processing unit <NUM> operates so as to alternately switch a communication period (first period) with the first communication unit <NUM> of the connection switching source and a scan period (second period) within which the second communication unit <NUM> of the connection switching source waits for a connection request. The connection processing unit <NUM> may place timing information that defines alternate switching between the first period and the second period into the waiting instruction signal such that the instruction processing unit <NUM> alternately and periodically switches the communication period with the first communication unit <NUM> and the scan period for waiting for a connection request from the second communication unit <NUM> in accordance with the timing information included in the waiting instruction signal.

It is to be noted that the connection processing unit <NUM> preferably sets timing information in response to the connection situation of the electronic apparatus <NUM> and the communication device <NUM>. At the point of time of S22 in <FIG>, the electronic apparatus <NUM> is in a stage in which it performs a new connection process with the communication device <NUM> and does not yet start data communication of voice data or the like with the first communication unit <NUM>. Therefore, the connection processing unit <NUM> sets timing information TI1 such that the electronic apparatus <NUM> can quickly establish wireless communication with the second communication unit <NUM>. For example, the connection processing unit <NUM> may set the timing information TI1 indicating that the second period is longer than the first period.

In the page scan mode carried out within a scan period (second period), the request processing unit <NUM> waits for a connection request from the second communication unit <NUM> that has the apparatus ID information included in the waiting instruction signal. In the second communication unit <NUM>, the connection processing unit <NUM> transmits a connection request including the apparatus ID information of the electronic apparatus <NUM> to the electronic apparatus <NUM> (S26). If the request processing unit <NUM> accepts the connection request, then a connection process is carried out between the request processing unit <NUM> and the connection processing unit <NUM>. Consequently, the second communication unit <NUM> is connected to the electronic apparatus <NUM> in the active mode (S28).

If the connection management unit <NUM> detects that connection is established between the second communication unit <NUM> and the electronic apparatus <NUM>, then it instructs the first communication unit <NUM> to cancel the connection to the electronic apparatus <NUM>. Receiving this instruction, the connection processing unit <NUM> transmits a disconnection request to the electronic apparatus <NUM> (S30). It is to be noted that the disconnection request may be transmitted from the electronic apparatus <NUM> to the first communication unit <NUM>. Thereafter, the connection between the first communication unit <NUM> and the electronic apparatus <NUM> is cancelled (S32) (for example by the communication device), and the electronic apparatus <NUM> is connected only to the second communication unit <NUM>. In this manner, in the communication system <NUM>, after the second communication unit <NUM> establishes connection the electronic apparatus <NUM>, the wireless connection between the first communication unit <NUM> and the electronic apparatus <NUM> is cancelled (for example by the communication device), and the electronic apparatus <NUM> is wirelessly connected only to the second communication unit <NUM>. The first communication unit <NUM> then operates in a page scan mode for waiting for a connection request from an external electronic apparatus <NUM> (S34) and waits for a connection request (paging) from an electronic apparatus <NUM> included in the connectable apparatus ID list.

The procedure when a first electronic apparatus <NUM> establishes connection to the communication device <NUM> is described above. In the following, a procedure when second and succeeding electronic apparatuses <NUM> establish connection to the communication device <NUM> is described with reference to connection transition diagrams depicting connection states is described.

<FIG> depicts a state in which the first electronic apparatus 200a is wirelessly connected to the second communication unit <NUM> in accordance with the wireless connection sequence depicted in <FIG>. As described above, the electronic apparatus 200a transmits a connection request to the first communication unit <NUM> to establish connection to the first communication unit <NUM> and then operates in the page scan mode in which it waits for a connection request from the second communication unit <NUM>. The electronic apparatus <NUM> receives a connection request from the second communication unit <NUM> and establishes connection to the second communication unit <NUM> and then cancels the connection to the first communication unit <NUM>. <FIG> depicts this state.

<FIG> depicts a state in which the second electronic apparatus 200b is wirelessly connected to the first communication unit <NUM>. The electronic apparatus 200b transmits a connection request to the first communication unit <NUM> to establish connection to the first communication unit <NUM> in the active mode.

The connection management unit <NUM> acquires a communication situation of the first communication unit <NUM> with an external apparatus and a communication situation of the second communication unit <NUM> with an external apparatus. In the connection state depicted in <FIG>, the first communication unit <NUM> is connected to one electronic apparatus 200b and the second communication unit <NUM> is connected to one electronic apparatus 200a. The connection management unit <NUM> acquires the number of electronic apparatus <NUM> to which each of the first communication unit <NUM> and the second communication unit <NUM> is connected as a communication situation. The allocation processing unit <NUM> executes a process for allocating the electronic apparatus 200b to one of the first communication unit <NUM> and the second communication unit <NUM> on the basis of the numbers of electronic apparatus <NUM> to which the first communication unit <NUM> and the second communication unit <NUM> are individually connected.

The allocation processing unit <NUM> allocates the electronic apparatus 200b to which connection is established newly to the first communication unit <NUM> or the second communication unit <NUM> such that the communication load on the first communication unit <NUM> with the external apparatus becomes equal to or lower than the communication load on the second communication unit <NUM> with the external apparatus. In the state in which the second electronic apparatus 200b establishes connection to the first communication unit <NUM> (state depicted in <FIG>), the first communication unit <NUM> is connected to one electronic apparatus 200b and the second communication unit <NUM> is connected to one electronic apparatus 200a, and the communication loads on the first communication unit <NUM> and the second communication unit <NUM> are equal to each other. Therefore, the allocation processing unit <NUM> determines that there is no problem in that the connection destination of the electronic apparatus 200b is the first communication unit <NUM> and accordingly determines that the connection destination of the electronic apparatus 200b is not to be changed.

<FIG> depicts a state in which the third electronic apparatus 200c is wirelessly connected to the first communication unit <NUM>. The electronic apparatus 200c transmits a connection request to the first communication unit <NUM> to establish connection to the first communication unit <NUM> in the active mode.

The connection management unit <NUM> acquires the connection number of external apparatus to the first communication unit <NUM> and the connection number of external apparatus to the second communication unit <NUM>. In the connection state depicted in <FIG>, the first communication unit <NUM> is connected to two electronic apparatuses 200b and 200c and the second communication unit <NUM> is connected to one electronic apparatus 200a. The allocation processing unit <NUM> allocates the electronic apparatus 200c to which connection is established newly to the first communication unit <NUM> or the second communication unit <NUM> such that the connection number of external apparatus to the first communication unit <NUM> becomes equal to or smaller than the connection number of external apparatus to the second communication unit <NUM>. In the state in which the third electronic apparatus 200c establishes connection to the first communication unit <NUM> (state depicted in <FIG>), the connection number of external apparatus to the first communication unit <NUM> is greater than the connection number of external apparatus to the second communication unit <NUM>. Therefore, the allocation processing unit <NUM> determines that the connection destination of the electronic apparatus 200c is the second communication unit <NUM> and accordingly determines to change the connection destination of the electronic apparatus 200c from the first communication unit <NUM> to the second communication unit <NUM>.

<FIG> depicts a state in which the electronic apparatus 200c is connected to the first communication unit <NUM> and the second communication unit <NUM> simultaneously. The first communication unit <NUM> transmits a signal (waiting instruction signal) for instructing the electronic apparatus 200c to enter a state in which it waits for a connection request to the electronic apparatus 200c, and while the electronic apparatus 200c maintains the connection to the first communication unit <NUM>, it operates in the page scan mode in which it waits for a connection request from the second communication unit <NUM>. The electronic apparatus 200c receives a connection request from the second communication unit <NUM> and establishes connection to the second communication unit <NUM>. <FIG> depicts this state.

<FIG> depicts a state in which the electronic apparatus 200c cancels the connection to the first communication unit <NUM>. The first communication unit <NUM> transmits a disconnection request to the electronic apparatus 200c to cancel the connection to the electronic apparatus 200c. <FIG> depicts this state.

<FIG> depicts a state in which the fourth electronic apparatus 200d is wirelessly connected to the first communication unit <NUM>. The electronic apparatus 200d transmits a connection request to the first communication unit <NUM> to establish connection to the first communication unit <NUM> in the active mode.

The connection management unit <NUM> acquires the connection number of external apparatus to the first communication unit <NUM> and the connection number of external apparatus to the second communication unit <NUM>. In the connection state depicted in <FIG>, the first communication unit <NUM> is connected to the two electronic apparatuses 200b and 200d, and the second communication unit <NUM> is connected to the two electronic apparatuses 200a and 200c. The allocation processing unit <NUM> allocates the electronic apparatus 200d to which connection is established newly to the first communication unit <NUM> or the second communication unit <NUM> such that the connection number of external apparatus to the first communication unit <NUM> becomes equal to or smaller than the connection number of external apparatus to the second communication unit <NUM>. In the state in which the fourth electronic apparatus 200d establishes connect to the first communication unit <NUM> (state depicted in <FIG>), the connection number of external apparatus to the first communication unit <NUM> is equal to the connection number of external apparatus to the second communication unit <NUM>. Therefore, the allocation processing unit <NUM> decides that the connection destination of the electronic apparatus 200d may be the first communication unit <NUM> and accordingly determines that the connection destination of the electronic apparatus 200d is not to be changed.

<FIG> depicts a state in which the third electronic apparatus 200c is disconnected from the second communication unit <NUM>. For example, if the user of the electronic apparatus 200c ends the game play of the electronic apparatus 200c and logs out from the device main body <NUM>, then the connection between the electronic apparatus 200c and the second communication unit <NUM> is cancelled.

After the connection between the electronic apparatus 200c and the communication device <NUM> is cancelled, the connection management unit <NUM> acquires the connection number of external apparatus to the first communication unit <NUM> and the connection number of external apparatus to the second communication unit <NUM>. In the connection state depicted in <FIG>, the first communication unit <NUM> is connected to the two electronic apparatuses 200b and 200d and the second communication unit <NUM> is connected to the one electronic apparatus 200a. The allocation processing unit <NUM> executes an allocation process taking it as a trigger (or in other words, in response to a detection) that the wireless connection to the electronic apparatus 200c to which the communication device <NUM> has been connected ends. In particular, the allocation processing unit <NUM> changes the connection destination of the electronic apparatus 200d, which has been connected already, such that the connection number of external apparatus to the first communication unit <NUM> becomes equal to or smaller than the connection number of external apparatus to the second communication unit <NUM>. In the state depicted in <FIG>, since the connection number of external apparatus to the first communication unit <NUM> is greater than the connection number of external apparatus to the second communication unit <NUM>, the allocation processing unit <NUM> determines to change the connection destination of the electronic apparatus 200d from the first communication unit <NUM> to the second communication unit <NUM>.

<FIG> depicts a state in which the electronic apparatus 200d is connected to the second communication unit <NUM>. When the connection destination is to be switched, the electronic apparatus 200d receives a waiting instruction signal from the first communication unit <NUM> and enters a state in which it waits for a connection request from the second communication unit <NUM>. The instruction processing unit <NUM> in the electronic apparatus 200d alternately and periodically performs switching between a communication period with the first communication unit <NUM> and a scan period for waiting for a connection request from the second communication unit <NUM> in accordance with timing signal included in the waiting instruction signal. If the request processing unit <NUM> in the electronic apparatus 200d accepts a connection request from the second communication unit <NUM>, then a connection process is carried out between the electronic apparatus 200d and the second communication unit <NUM>. In this manner, going through the state in which the electronic apparatus 200d is connected to the first communication unit <NUM> and the second communication unit <NUM> simultaneously, the electronic apparatus 200d is disconnected from the first communication unit <NUM> and is connected only to the second communication unit <NUM>.

At the point of time at which a waiting instruction signal is received, the electronic apparatus 200d is in a state in which data communication of voice data or the like with the first communication unit <NUM> is being carried out already, and the circumstances are different from those in the case where a new connection process is performed as indicated at S22 of <FIG>. Therefore, the connection processing unit <NUM> sets timing information TI2 such that, while priority is given to maintaining data communication between the electronic apparatus 200d and the first communication unit <NUM>, the connection processing unit <NUM> can establish wireless communication to the second communication unit <NUM> during the period. The connection processing unit <NUM> may set the timing information TI2 such that the communication period (first period) with the first communication unit <NUM> that is the connection switching source is made longer than the scan period (second period) within which the connection processing unit <NUM> waits for a connection request from the second communication unit <NUM> that is the connection switching destination. In other words, timing information TI1 transmitted upon new connection processing may be different from the timing information TI2 transmitted after data communication is started.

It is to be noted that, while, in the example of <FIG>, the connection destination of the electronic apparatus 200d has been switched from the first communication unit <NUM> to the second communication unit <NUM>, also when the connection destination is to be switched from the second communication unit <NUM> to the first communication unit <NUM>, the connection processing unit <NUM> may place the timing information TI2 into a waiting instruction signal and the second communication unit <NUM> may transmit the waiting instruction signal to the electronic apparatus 200d.

In the communication system <NUM> of the embodiment, the allocation processing unit <NUM> determines the connection destination of an external apparatus to the first communication unit <NUM> or the second communication unit <NUM> such that the communication load with an external apparatus on the first communication unit <NUM> becomes equal to or lower than the communication load with an external apparatus on the second communication unit <NUM>.

Therefore, even if data communication is started between the communication device <NUM> and the electronic apparatus <NUM>, the switching process of the connection destination of the electronic apparatus <NUM> is carried out in response to a change of the connection environment between the communication device <NUM> and the electronic apparatus <NUM>. In particular, if, after a waiting instruction signal including the timing information TI2 is transmitted to the electronic apparatus <NUM> in a state in which one of the first communication unit <NUM> and the second communication unit <NUM> is wirelessly connected to the electronic apparatus <NUM>, the electronic apparatus <NUM> establishes the other one of the first communication unit <NUM> and the second communication unit <NUM>, then the wireless connection between the one of the first communication unit <NUM> and the second communication unit <NUM> and the electronic apparatus <NUM> is cancelled. As the allocation processing unit <NUM> determines a connection destination of an external apparatus in accordance with a reference using a communication load, stable page scan mode operation by the first communication unit <NUM> is guaranteed to the new external apparatus.

In the communication system <NUM> of the embodiment, since the electronic apparatus <NUM> performs a paging process for the first communication unit <NUM>, when connection between the first communication unit <NUM> and the electronic apparatus <NUM> is first established, the electronic apparatus <NUM> becomes (or operates as) a master and the first communication unit <NUM> becomes (or operates as) a slave. Thereafter, in order to transmit and receive data of voice chat, a game play and so forth, it is necessary for the communication device <NUM> and the electronic apparatus <NUM> to become a master and a slave, respectively, such that communication of the electronic apparatus <NUM> is controlled by the communication device <NUM>. Therefore, the role management unit <NUM> transmits a role switching instruction for switching the roles (roles) of the master and the slave to the electronic apparatus <NUM> through the first communication unit <NUM> to switch the electronic apparatus <NUM> to the slave and switch the first communication unit <NUM> to the master as indicated at S20 of <FIG>.

Although, in <FIG>, only one electronic apparatus <NUM> has established wireless connection to the first communication unit <NUM> at the point of time of S18 because <FIG> depicts a sequence from a state of the waken on BT, after the communication device <NUM> is started, the electronic apparatus 200c may try to newly establish connection to the first communication unit <NUM> in a state in which the electronic apparatus 200b is already connected to the first communication unit <NUM> in the active mode, for example, as depicted in <FIG>.

<FIG> depicts a timing chart when the electronic apparatus 200b pages the first communication unit <NUM>. At this time, the first communication unit <NUM> is not connected to an external apparatus. In the case where the first communication unit <NUM> is not connected to an external apparatus, it waits for a connection request in the first mode in which a waiting time period P1 is comparatively (that is, relatively) long.

The electronic apparatus 200b transmits a connection request (paging) to the first communication unit <NUM>. The first communication unit <NUM> establishes connection to the electronic apparatus 200b at time t1. At time t1, the first communication unit <NUM> and the electronic apparatus 200b are in the state at S18 in the sequence of <FIG>, and at the point of time of establishment of connection, the first communication unit <NUM> becomes the slave and the electronic apparatus 200b becomes the master. Thus, the role management unit <NUM> recognizes the roles (roles) of them.

After the electronic apparatus 200b is connected, the role management unit <NUM> controls the period within which the first communication unit <NUM> is to operate as the slave in response to a communication situation with other external apparatus other than the electronic apparatus 200b to the first communication unit <NUM>. At the point of time of time t1 depicted in <FIG>, the first communication unit <NUM> is not connected to any other external apparatus. In this case, the role management unit <NUM> causes the first communication unit <NUM> to operate as the slave during a period within which the role switching process is carried out at time t3 after time t1.

After time t1, the first communication unit <NUM> and the electronic apparatus 200b transmit information necessary for data communication such as clock information and communication parameters, and after such procedure ends and such information has been transmitted or transferred, at time t2, the role management unit <NUM> transmits a role switching instruction for switching the roles (roles) of the master and the slave to the electronic apparatus 200b through the first communication unit <NUM>. The connection processing unit <NUM> in the first communication unit <NUM> and the instruction processing unit <NUM> in the electronic apparatus 200b execute switching of the roles in synchronism with each other at time t3 after a predetermined period of time after transmission of the role switching instruction. Consequently, the electronic apparatus <NUM> operates as the slave and the first communication unit <NUM> operates as the master. In this manner, if any other external apparatus than the electronic apparatus 200b is not connected, then the role management unit <NUM> may cause the first communication unit <NUM> to operate as the salve during a period until a role switching process is carried out in accordance with a role switching instruction.

Therefore, in general terms, when the communication unit is connected to a given external apparatus, the control unit is configured to control a period during which the communication unit operates as the slave in response to a communication situation of the communication unit with a different external apparatus from the given external apparatus.

<FIG> depicts a timing chart when the electronic apparatus 200c performs paging to the first communication unit <NUM>. At this time, the first communication unit <NUM> already is in a state in which it is communicating with the electronic apparatus 200b in the active mode. In the case where the first communication unit <NUM> is in connection to an external apparatus, it waits for a connection request in a second mode in which a waiting time period P2 is relatively short. Consequently, the first communication unit <NUM> can wait for a connection request from the new electronic apparatus 200c while maintaining the communication of voice data or the like with the electronic apparatus 200b.

To this end, the waiting time period P2 is preferably set to a period of time within which communication between the first communication unit <NUM> and the electronic apparatus 200b is not disturbed. For example, in the case where the communication cycle of voice data between the first communication unit <NUM> and the electronic apparatus 200b is <NUM>, the waiting time period P2 is preferably set to a period of time shorter than <NUM>. This makes it possible for the first communication unit <NUM> to wait for a connection request from the new electronic apparatus 200c between time zones within which voice data is transmitted and received.

The electronic apparatus 200c transmits a connection request (paging) to the first communication unit <NUM>. The first communication unit <NUM> establishes connection to the electronic apparatus 200c at time t11. At this time, the first communication unit <NUM> becomes the slave and the electronic apparatus 200c becomes the master, and the role management unit <NUM> recognizes the roles (roles) of them. After the electronic apparatus 200c is connected, the role management unit <NUM> controls the period during which the first communication unit <NUM> operates as the slave in response to a communication situation of the first communication unit <NUM> with other external apparatus than the electronic apparatus 200c. In the state depicted in <FIG>, the first communication unit <NUM> is connected already to the electronic apparatus 200b, and the role management unit <NUM> controls the period during which the first communication unit <NUM> operates as the slave in the following manner.

Different from the situation depicted in <FIG>, at time t11, the first communication unit <NUM> periodically performs data communication with the electronic apparatus 200b, and if the first communication unit <NUM> continues to be the slave within a period up to time t13 at which role switching is performed on the basis of the role switching instruction, then the first communication unit <NUM> cannot communicate with the electronic apparatus 200b. This signifies that, in the case where the user of the electronic apparatus 200b is voice chatting, the voice chart is temporarily interrupted during a period from time t11 to time t13.

Therefore, when the first communication unit <NUM> establishes connection to the electronic apparatus 200c, if it is already connected to the other electronic apparatus 200b, then the role management unit <NUM> alternately performs switching between a period during which the first communication unit <NUM> operates as the salve and another period during which the first communication unit <NUM> operates as the master. The period during which the first communication unit <NUM> operates as the master is a period within which data communication is possible between the first communication unit <NUM> and the electronic apparatus 200b, and the period during which the first communication unit <NUM> operates as the slave is a period within which transmission and reception of information necessary for data communication between the first communication unit <NUM> and the electronic apparatus 200c are possible.

<FIG> depicts a state of the first communication unit <NUM> from time t11 to time t13. Here, "S" represents a period during which the first communication unit <NUM> is the slave, and "M" represents a period during which the first communication unit <NUM> is the master. The role management unit <NUM> periodically and alternately sets a slave period and a master period such that the first communication unit <NUM> can transmit and receive information necessary for communication with the electronic apparatus 200c within the slave period and can communicate data with the electronic apparatus 200b within the master period.

The period within which the first communication unit <NUM> operates as the slave is set on the basis of the communication cycle with the electronic apparatus 200b connected already. For example, in the case where the communication cycle of voice data between the first communication unit <NUM> and the electronic apparatus 200b is <NUM>, the period during which the first communication unit <NUM> operates as the slave is preferably set to a period shorter than <NUM>. This makes it possible to transmit and receive information to and from the new electronic apparatus 200c between time zones within which voice data is transmitted and received.

In the BT protocol, a BT communication apparatus that becomes the master performs transmission in an even-numbered slot, and another BT communication device that becomes the slave performs transmission in an odd-numbered slot. The slot cycle is <NUM>, and transmission operation by the master and transmission operation by the slave are defined by the BT clock of the master.

<FIG> depicts the BT clock. A clock counter incorporated in a BT communication apparatus generates a <NUM>-bit BT clock whose clock rate is <NUM>. Here, a slot is defined by the bit C1, and the master performs transmission operation in even-numbered slots (C1 = <NUM>) and performs reception operation in odd-numbered slots (C1 = <NUM>).

In the communication system <NUM> of the embodiment, the communication device <NUM> includes two communication units of a first communication unit <NUM> and a second communication unit <NUM>. For example, if the second communication unit <NUM> performs reception operation during transmission operation of the first communication unit <NUM>, then the transmission operation of the first communication unit <NUM> becomes interference with the reception operation of the second communication unit <NUM>. Therefore, it is preferable to avoid collision of transmission and reception between the first communication unit <NUM> and the second communication unit <NUM>.

<FIG> depicts a timing chart of transmission and reception in the first communication unit <NUM> and the second communication unit <NUM>. In the first communication unit <NUM>, the communication controlling unit <NUM> performs switching between a transmission operation and a reception operation in response to the value of a predetermined bit (C1) of the clock counter <NUM> (which generates a clock signal of the first communication unit having a plurality of successive bits (C0, C1. Also in the second communication unit <NUM>, the communication controlling unit <NUM> similarly performs switching between a transmission operation and a reception operation in response to the value of the predetermined bit (C1) of the clock counter <NUM> (which generates a clock signal of the second communication unit having a plurality of successive bits). Accordingly, by synchronizing the value of the predetermined bit (C1) of the clock counter <NUM> and the value of the predetermined bit (C1) of the clock counter <NUM> with each other, it is possible to synchronize the transmission operation and the reception operation of the first communication unit <NUM> and the second communication unit <NUM> with each other as depicted in <FIG>. The predetermined bit (C1) of the clock counter <NUM> and the predetermined bit (C1) of the clock counter <NUM> are bits at the same position that is the second bit from the least significant bit (LSB).

The first communication unit <NUM> and the second communication unit <NUM> in the embodiment are formed on the same chip, and the clock counter <NUM> and the clock counter <NUM> may generate a BT clock on the basis of a clock signal of a common system clock oscillator.

The clock counter <NUM> supplies a counter reset signal, which is a side band signal, to the clock counter <NUM>. The clock counter <NUM> outputs the counter reset signal in the case where the lowest <NUM> bits (C1, C0) are <NUM>. When the counter reset signal is received, the clock counter <NUM> sets the lowest <NUM> bits (C1, C0) to <NUM>. Consequently, the clock counter <NUM> and the clock counter <NUM> can synchronize the values of the bit C1, which defines a slot, with each other, and the communication controlling unit <NUM> of the first communication unit <NUM> and the communication controlling unit <NUM> of the second communication unit <NUM> can synchronize the transmission and reception operations with each other.

It is to be noted that the communication controlling unit <NUM> and the communication controlling unit <NUM> synchronize the transmission and reception operations with each other and preferably communicate with each other with frequencies different from each other. Since the frequency hopping pattern is determined using the BT device address of the master, The communication controlling unit <NUM> may determine a frequency hopping pattern using the BT device address of the first communication unit <NUM> as it is, and the communication controlling unit <NUM> may determine a frequency hopping pattern by offsetting the BT device address of the first communication unit <NUM> by a predetermined value. This makes it possible to make the frequencies to be used by the communication controlling unit <NUM> and the communication controlling unit <NUM> different from each other with certainty.

It is to be noted that, although the first communication unit <NUM> and the second communication unit <NUM> in the embodiment include the clock counter <NUM> and the clock counter <NUM>, respectively, in a different example, a clock counter common to the first communication unit <NUM> and the second communication unit <NUM> disposed on the same chip may be provided such that a BT clock from the common clock counter is supplied to the first communication unit <NUM> and the second communication unit <NUM>. As an alternative, the clock counter <NUM> may generate a BT clock from a clock signal of a system clock oscillator and supply the generated BT clock and a counter reset signal to the clock counter <NUM> to synchronize the values of the bit C1 that specifies a slot with each other. It is to be noted that, although it is presupposed in the present embodiment that the first communication unit <NUM> and the second communication unit <NUM> are disposed on the same chip, even in the case where they are disposed on different chips, the values of the bit C1 that defines a slot can be synchronized with each other by supplying a counter reset signal from the clock counter <NUM> to the clock counter <NUM>.

Therefore, in example embodiments, bit synchronization of the clock counter <NUM> and the clock counter <NUM> is performed only for the low-order <NUM> bits (C1, C0). Each bit can define a socalled slot (or period of time) within a clock cycle defined by the succession of bits. As mentioned above, the master performs transmission operation in even-numbered slots (C1 = <NUM>) and performs reception operation in odd-numbered slots (C1 = <NUM>). To achieve this, it is possible that only bit C1 may be synchronized, but in example arrangements both C1 and C0 are set to <NUM> for counter reset. Bit C2 and higher are not affected by the counter reset. Therefore, a "given bit" may be C1 or it may refer to C0 and C1.

The present invention has been described on the basis of the embodiment. The embodiment is exemplary and it can be recognized by those skilled in the art that various modifications are possible in regard to the components or processes of the embodiment and that also such modifications remain within the scope of the present invention as defined by the appended claims.

In the sequence depicted in <FIG>, where the electronic apparatus <NUM> operates in the page scan mode in a state in which it is notified of apparatus ID information of the second communication unit <NUM> from the first communication unit <NUM>, the electronic apparatus <NUM> can respond fully to a connection request from the second communication unit <NUM> that has the notified apparatus ID information. Even if the electronic apparatus <NUM> is not notified of the apparatus ID information of the second communication unit <NUM>, it may respond to a connection request from the second communication unit <NUM>. It is to be noted that, when the electronic apparatus <NUM> is notified of the apparatus ID information of the second communication unit <NUM>, it is possible for the electronic apparatus <NUM> to transmit a connection request including the apparatus ID information of the second communication unit <NUM> to the second communication unit <NUM> to establish connection.

Example methods representing at least some of the above techniques will now be described with reference to schematic flowcharts provided as <FIG>.

<FIG> is a schematic flowchart illustrating a wireless connection method for establishing wireless connection to a communication device that includes a plurality of communication units of the same type, the method comprising:.

<FIG> is a schematic flowchart illustrating a method of operation of a communication device having a first communication unit and a second communication unit of a same type as that of the first communication unit, the communication device being wirelessly connectable to an external apparatus, the method comprising:.

<FIG> is a schematic flowchart illustrating a connection destination determination method for determining a connection destination of an external apparatus in a communication device that includes a first communication unit and a second communication unit of a same type as that of the first communication unit, the method comprising:.

<FIG> is a schematic flowchart illustrating a method for wirelessly connecting a communication device including a first communication unit and a second communication unit of a same type as that of the first communication unit to an external apparatus, the first communication unit or the second communication unit carrying out:.

<FIG> is a schematic flowchart illustrating a wireless connection method for establishing wireless connection to a communication device, comprising:.

<FIG> is a schematic flowchart illustrating a method of operation of a communication device including a communication unit that operates as one of a master and a slave so as to control a state of the communication unit, the method comprising:.

<FIG> is a schematic flowchart illustrating a method of operation of communication device having a first communication unit and a second communication unit of a type same as that of the first communication unit; the method comprising:.

<FIG> schematically illustrates a computer or computer processor which may be used to implement any one or more components of the communication device or the electronic apparatus discussed above. For example, control or other functions such as those provided by any one or more of the units <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be implemented by executing program instructions by such a computer. Similarly, control or other functions such as those provided by any one or more of the units <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be implemented by executing program instructions by such a computer. The computer comprises a central processing unit (CPU) <NUM>, a random access memory (RAM) <NUM>, a non-transitory machine-readable storage medium (NTMRSM) <NUM> such as a read only memory, hard disk, optical disk, flash memory or the like, for example by which the program instructions are provided, and input/output (I/O) circuitry <NUM>, the components being interconnected by a bus arrangement <NUM>.

A description will now be given of a variation.

<FIG> is a view depicting a sequence by which the electronic apparatus <NUM> and the communication device <NUM> according to a variation establish wireless connection therebetween. The procedures denoted by the same number in <FIG> and in <FIG> are identical or similar procedures. In the wake on BT state, the first communication unit <NUM> operates in a page scan mode in which it waits for a connection request from an external electronic apparatus <NUM> (S10). The connection processing unit <NUM> of the first communication unit <NUM> waits for a connection request (paging) from an electronic apparatus <NUM> included in the connectable apparatus ID list.

In the control unit <NUM>, the connection management unit <NUM> downloads firmware into the second communication unit <NUM> through the USB connection to initialize the second communication unit <NUM>. Consequently, the second communication unit <NUM> is placed into a wirelessly connectable state to an external electronic apparatus <NUM> (S16). The connection management unit <NUM> executes an authentication process and an encryption process with the electronic apparatus <NUM> and the first communication unit <NUM> establishes connection to the electronic apparatus <NUM> in an active mode that is a data transfer mode in which data can be transferred (S18). An active mode is a connection mode in which the communication block <NUM> and the electronic apparatus <NUM> transmit and receive data to and from each other using a plurality of continuous slots. To communicate data such as voice data between the communication block <NUM> and the electronic apparatus <NUM>, it is necessary for the communication block <NUM> and the electronic apparatus <NUM> to be connected to each other in the active mode.

At the point of time that a connection is established in the active mode, the electronic apparatus <NUM> that is the paging device is the master, and the first communication unit <NUM> that is the paged device is the slave. The role management unit <NUM> transmits a role switching instruction for switching the roles (roles) of the master and the slave to the electronic apparatus <NUM> through the first communication unit <NUM> (S20). In the electronic apparatus <NUM>, the instruction processing unit <NUM> accepts the role switching instruction. The connection processing unit <NUM> in the first communication unit <NUM> and the instruction processing unit <NUM> execute switching of the roles of the first communication unit <NUM> and the electronic apparatus <NUM> in synchronism with each other after a predetermined interval of time after the role switching instruction is transmitted. Consequently, the electronic apparatus <NUM> starts operation as the slave and the first communication unit <NUM> of the communication device <NUM> starts operation as the master. After that, the first communication unit <NUM> instructs the electronic apparatus <NUM> to establish a state in which the electronic apparatus <NUM> waits for acceptance of a connection request (S22).

The connection management unit <NUM> acquires a communication situation of the first communication unit <NUM> with an external apparatus and a communication situation of the second communication unit <NUM> with an external apparatus. At the point of time of establishment of connection at S18, the first communication unit <NUM> is connected to one electronic apparatus <NUM>, and the second communication unit <NUM> is not connected to any electronic apparatus <NUM>.

<FIG> depicts a state in which the first electronic apparatus 200a is connected to the first communication unit <NUM> in the active mode. The connection management unit <NUM> may acquire the numbers of external apparatuses to which the first communication unit <NUM> and the second communication unit <NUM> are respectively connected in the active mode as the communication situations.

In the variation, the electronic apparatus <NUM> is connected to one of the first communication unit <NUM> and the second communication unit <NUM> in a data transfer mode in which data can be transferred and is connected to the other of the first communication unit <NUM> and the second communication unit <NUM> in a data non-transfer mode in which data is not transferred. A detailed description will follow.

In the variation, the data transfer mode is an active mode in which a data transfer period is secured. In the data transfer mode, data used in a process executed in the information processing device incorporating the communication device <NUM> is transmitted and/or received. In the case where the information processing device is a game device, data used to run the game or voice data for voice chats may be transmitted and received in the data transfer mode.

In the case where the electronic apparatus <NUM> is a peripheral such as a headset or a game controller, the electronic apparatus <NUM> transfers data input by the user to the communication unit in the data transfer mode, and the communication unit transfers output data for the user to the electronic apparatus <NUM> in the data transfer mode. The data input by the user includes, for example, voice data originated by the user or data necessary for execution of the game (application). The data necessary for execution of the game may include operation data for the controller and motion data for the controller. The output data for the user may include voice data in the game and voice data originated by a further user.

The data non-transfer mode may be a connection mode in which data cannot be transferred or may be a connection mode in which data can be transferred but is not transferred. In the data non-transfer mode, data input by the user and output data for the user are not transferred between the electronic apparatus <NUM> and the communication unit. In the variation, control data for the electronic apparatus <NUM> or state data indicating the state of the electronic apparatus <NUM> are transferred in the data transfer mode, but these items of data may be transferred in the non-transfer mode exceptionally.

Thus, the electronic apparatus <NUM> according to the variation is connected to one of the first communication unit <NUM> and the second communication unit <NUM> such that data communication is enabled and connected to the other of the first communication unit <NUM> and the second communication unit <NUM> such that data communication is not performed. Where three or more communication units are provided in the communication block <NUM>, for example, the electronic apparatus <NUM> is connected to one of the communication units in the data transfer mode and connected to the other communication units in the data non-transfer mode.

In the data non-transfer mode, an extremely short period of time is defined within a communication cycle as a communication enabled period for maintaining synchronization, and the remainder of communication cycle is defined as a non-communication period. For example, the communication enabled period in the communication cycle in the data non-transfer mode may be <NUM>/<NUM> or shorter than the non-communication period. The data non-transfer mode of the variation may be a sniff mode in which packets for maintaining synchronization are transmitted and received by using only a predetermined number of slots (e.g., two slots) in a predetermined time interval (N slots). In the sniff mode, the N slots defining the predetermined time interval are called a sniff cycle, and N may be such that N=<NUM>. The sniff mode is a power saving connection mode used for the purpose of operating in a power saving mode and maintaining synchronization. The data non-transfer mode may be a connection mode of a format other than the sniff mode so long as it is a mode in which data is not transferred but synchronization of communication can be maintained.

The electronic apparatus <NUM> connected to the communication unit in the sniff mode transmits and receives packets to and from the communication unit only during the two sniff slots defined within the sniff cycle comprised of continuous <NUM> slots. During the <NUM> slots other than the two sniff slots, the electronic apparatus <NUM> does not perform any process for the communication unit connected in the sniff mode. In the sniff mode, the master transmits a predetermined poll packet, and the slave receiving the packet returns a null packet, completing packet communication in the sniff cycle for maintaining synchronization. In the sniff mode, communication parameters for connection are maintained so that a new paging processes or authentication process is not necessary in changing the connection mode from the sniff mode to the active mode.

The allocation processing unit <NUM> executes an allocation process for determining the connection destination of the external apparatus in the data transfer mode (active mode) to the first communication unit <NUM> or the second communication unit <NUM> on the basis of the communication situations of the first communication unit <NUM> and the second communication unit <NUM> acquired by the connection management unit <NUM>. The allocation processing unit <NUM> preferably determines the connection destination of the external apparatus in the active mode to the first communication unit <NUM> or the second communication unit <NUM> such that the communication load with the external apparatus on the first communication unit <NUM> is equal to or lower than the communication load with the external apparatus on the second communication unit <NUM>. In other words, the allocation processing unit <NUM> preferably makes the communication load on the first communication unit <NUM> having the function of waiting for a connection request from the external electronic apparatus <NUM> equal to or lower than the communication load on the second communication unit <NUM> not having that function.

The allocation processing unit <NUM> preferably performs an allocation process not to make the communication load on the second communication unit <NUM> excessively larger than the communication load on the first communication unit <NUM> while ensuring that the communication load on the first communication unit <NUM> is equal to or lower than the communication load on the second communication unit <NUM>. For example, the allocation processing unit <NUM> preferably performs an allocation process to ensure that a difference between the communication load on the second communication unit <NUM> and the communication load on the first communication unit <NUM> does not exceed a predetermined threshold value on the condition that the communication load on the first communication unit <NUM> is equal to or lower than the communication load on the second communication unit <NUM>.

In the variation, the first communication unit <NUM> and the second communication unit <NUM> are connected to the electronic apparatus <NUM> in one of the active mode and the sniff mode. The communication load carried during the connection in the sniff mode is extremely lower than the communication load carried during the connection in the active mode. In this background, the allocation processing unit <NUM> may determine the connection destination of the external apparatus in the active mode by disregarding the communication load during the sniff mode and determining the relative magnitudes of the communication loads based on the number of external apparatuses to which the first communication unit <NUM> is connected in the active mode and the number of external apparatuses to which the second communication unit <NUM> is connected in the active mode.

When only one electronic apparatus <NUM> is connected to the communication device <NUM> as shown in <FIG>, the allocation processing unit <NUM> preferably determines the connection destination of the electronic apparatus <NUM> in the active mode to the second communication unit <NUM> to make the communication load on the first communication unit <NUM> lighter than the communication load on the second communication unit <NUM>.

Thus, the communication load to be used as a reference for decision of an allocation destination by the allocation processing unit <NUM> may be the number of external apparatus to which each communication unit is connected in the active mode. Therefore, the allocation processing unit <NUM> may allocate an external apparatus to the first communication unit <NUM> or the second communication unit <NUM> in the active mode such that the number of external apparatuses to which the first communication unit <NUM> is connected in the active mode is equal to or smaller than the number of external apparatuses to which the second communication unit <NUM> is connected in the active mode.

It is to be noted that the communication load to be used as a reference may be a communication data amount of each communication unit with an external apparatus. Although the data amount of voice data in voice chat with an electronic apparatus <NUM> is great, the data amount of operation data of a game controller is small. Therefore, the connection management unit <NUM> may monitor the communication data amount between each communication unit and an electronic apparatus <NUM>, and the allocation processing unit <NUM> may determine the connection destination of the electronic apparatus <NUM> such that the communication load on the first communication unit <NUM> becomes lower than the communication load on the second communication unit <NUM>. The communication load to be used as a reference may be a communication error rate in each communication unit or may be a combination of some of them.

Alternatively, the communication load to be used as a reference may be predicted based on functions of the electronic apparatus <NUM> or the on/off state of the functions. For example, if a microphone is not attached to the electronic apparatus <NUM>, it is predicted that the communication load on the electronic apparatus <NUM> is low, and, if a microphone is attached, on the other hand, it is predicted that the communication load on the electronic apparatus <NUM> is high or will become high. The connection management unit <NUM> may notify the allocation processing unit <NUM> of the availability of functions in the electronic apparatus <NUM> or the on/off state of the functions. The allocation processing unit <NUM> may determine the connection destination of the electronic apparatus <NUM> by predicting the communication load.

In the state shown in <FIG>, only one electronic apparatus 200a is already connected to the communication device <NUM>. Therefore, the allocation processing unit <NUM> determines to change the connection destination of the electronic apparatus 200a in the active mode from the first communication unit <NUM> to the second communication unit <NUM>. The allocation processing unit <NUM> initiates a connection process of the already connected electronic apparatus to the second communication unit <NUM>. Specifically, the allocation processing unit <NUM> causes the electronic apparatus 200a to operate in a scan mode (such as the page scan mode) and causes the second communication unit <NUM> to transmit a connection request to the electronic apparatus 200a. To this end, at S22, the first communication unit <NUM> transmits a signal (waiting instruction signal) for instructing the electronic apparatus 200a to establish a state in which the electronic apparatus 200a waits for a connection request from the second communication unit <NUM>.

The allocation processing unit <NUM> notifies the first communication unit <NUM> and the second communication unit <NUM> that the connection destination of the electronic apparatus 200a in the active mode is to be switched from the first communication unit <NUM> to the second communication unit <NUM>. At this time, the allocation processing unit <NUM> notifies the first communication unit <NUM> and the second communication unit <NUM> also of apparatus ID information (BT device address) of the electronic apparatus 200a. Consequently, the first communication unit <NUM> and the second communication unit <NUM> recognize that they are to operate such that the electronic apparatus 200a currently connected to the first communication unit <NUM> in the active mode is connected to the second communication unit <NUM> in the active mode and to the first communication unit <NUM> in the sniff mode.

In the first communication unit <NUM>, the connection processing unit <NUM> transmits a waiting instruction signal to the electronic apparatus 200a (S22). The waiting instruction signal may include identification information of an apparatus (for example, communication unit) from which a connection request is to be transmitted, in the present example, apparatus ID information of the second communication unit <NUM>. In the electronic apparatus 200a, the instruction processing unit <NUM> receives a waiting instruction signal and accepts an instruction to enter a state in which it waits for a connection request from the second communication unit <NUM>. Consequently, while the instruction processing unit <NUM> maintains the connection to the first communication unit <NUM> in the active mode, the request processing unit <NUM> operates in the page scan mode for waiting for a connection request from the second communication unit <NUM> (S24).

At this time, the instruction processing unit <NUM> operates so as to alternately switch a communication period (first period) for communication with the first communication unit <NUM> and a scan period (second period) for waiting for a connection request from the second communication unit <NUM>. The connection processing unit <NUM> may place timing information that defines alternate switching between the first period and the second period into the waiting instruction signal such that the instruction processing unit <NUM> alternately and periodically switches between the communication period for communication with the first communication unit <NUM> and the scan period for waiting for a connection request from the second communication unit <NUM> in accordance with the timing information included in the waiting instruction signal.

It is to be noted that the connection processing unit <NUM> preferably sets timing information in response to the connection situation of the electronic apparatus <NUM> and the communication device <NUM> in the active mode. At the point of time of S22 in <FIG>, the electronic apparatus 200a is in a stage in which it performs a new connection process with the communication device <NUM> and does not yet start data communication of voice data or the like with the first communication unit <NUM>. Therefore, the connection processing unit <NUM> sets timing information TI1 such that the electronic apparatus 200a can quickly establish wireless connection with the second communication unit <NUM>. For example, the connection processing unit <NUM> may set the timing information TI1 indicating that the second period is longer than the first period.

In the page scan mode carried out within a scan period (second period), the request processing unit <NUM> waits for a connection request from the second communication unit <NUM> that has the apparatus ID information included in the waiting instruction signal. In the second communication unit <NUM>, the connection processing unit <NUM> transmits a connection request including the apparatus ID information of the electronic apparatus 200a to the electronic apparatus 200a (S26). If the request processing unit <NUM> accepts the connection request, then a connection process including an authentication process and an encryption process is carried out between the request processing unit <NUM> and the connection processing unit <NUM>. Consequently, the second communication unit <NUM> is connected to the electronic apparatus <NUM> in the active mode (S28).

<FIG> depicts a state in which the first electronic apparatus 200a is connected to the first communication unit <NUM> and the second communication unit <NUM> in the active mode. If the connection management unit <NUM> detects that the second communication unit <NUM> and the electronic apparatus 200a are connected, then it instructs the first communication unit <NUM> to change the connection mode for connection to the electronic apparatus <NUM> a to the sniff mode. Receiving this instruction, the connection processing unit <NUM> transmits a change request to the electronic apparatus <NUM> to change the connection mode (S40). It is to be noted that the mode change request may be transmitted from the electronic apparatus <NUM> to the first communication unit <NUM>. Thereafter, the connection mode between the first communication unit <NUM> and the electronic apparatus 200a is changed to the sniff mode (S42). The first communication unit <NUM> then operates in a page scan mode for waiting for a connection request from an external electronic apparatus <NUM> (S34) and waits for a connection request (paging) from an electronic apparatus <NUM> included in the connectable apparatus ID list.

The procedure when a first electronic apparatus 200a establishes connection to the communication device <NUM> is described above. In the following, a procedure when second and succeeding electronic apparatuses <NUM> establish connection to the communication device <NUM> is described. <FIG> depicts a state in which the first electronic apparatus 200a is wirelessly connected to the second communication unit <NUM> in the active mode and wirelessly connected to the first communication unit <NUM> in the sniff mode in accordance with the wireless connection sequence depicted in <FIG>.

<FIG> depicts a state in which the second electronic apparatus 200b is wirelessly connected to the first communication unit <NUM> in the active mode. The electronic apparatus 200b transmits a connection request to the first communication unit <NUM> to establish connection to the first communication unit <NUM> in the active mode.

The connection management unit <NUM> acquires a communication situation of the first communication unit <NUM> with an external apparatus and a communication situation of the second communication unit <NUM> with an external apparatus. In the connection state depicted in <FIG>, the first communication unit <NUM> is connected to one electronic apparatus 200b in the active mode and the second communication unit <NUM> is connected to one electronic apparatus 200a in the active mode. The connection management unit <NUM> acquires the numbers of electronic apparatuses <NUM> to which the first communication unit <NUM> and the second communication unit <NUM> are respectively connected in the active mode as the communication situations. The allocation processing unit <NUM> executes a process for determining the connection destination of the electronic apparatus 200b in the active mode to the first communication unit <NUM> or the second communication unit <NUM> on the basis of the numbers of electronic apparatus <NUM> to which the first communication unit <NUM> and the second communication unit <NUM> are respectively connected in the active mode.

The allocation processing unit <NUM> determines the connection destination of the newly connected electronic apparatus <NUM> in the active mode to the first communication unit <NUM> or the second communication unit <NUM> such that the communication load with the external apparatus on the first communication unit <NUM> is equal to or lower than the communication load with the external apparatus on the second communication unit <NUM>. In the state in which the second electronic apparatus 200b establishes connection to the first communication unit <NUM> in the active mode (state depicted in <FIG>), the first communication unit <NUM> is connected to one electronic apparatus 200b in the active mode and the second communication unit <NUM> is connected to one electronic apparatus 200a in the active mode, and the communication loads on the first communication unit <NUM> and the second communication unit <NUM> are equal to each other. Therefore, the allocation processing unit <NUM> determines that there is no problem in that the connection destination of the electronic apparatus 200b in the active mode is the first communication unit <NUM>.

In this way, the second electronic apparatus 200b is determined to be wirelessly connected to the first communication unit <NUM> in the active mode and wirelessly connected to the second communication unit <NUM> in the sniff mode. Before being connecting to the second communication unit <NUM> in the sniff mode, the electronic apparatus 200b is connected to the second communication unit <NUM> in the active mode through the steps of S24, S26, and S28 shown in <FIG>.

<FIG> depicts a state in which the second electronic apparatus 200b is connected to the first communication unit <NUM> and the second communication unit <NUM> in the active mode. If the connection management unit <NUM> detects that the second communication unit <NUM> and the electronic apparatus 200a are connected in the active mode, then it instructs the second communication unit <NUM> to change the connection mode for connection to the electronic apparatus 200b to the sniff mode. Receiving this instruction, the connection processing unit <NUM> transmits a change request to the electronic apparatus <NUM> to change the connection mode. It is to be noted that the mode change request may be transmitted from the electronic apparatus <NUM> to the second communication unit <NUM>. Thereafter, the connection mode between the second communication unit <NUM> and the electronic apparatus 200b is changed to the sniff mode.

<FIG> depicts a state in which the connection mode between the second communication unit <NUM> and the electronic apparatus 200b is changed to the sniff mode. Thus, in the variation, the control unit <NUM> connects one of the first communication unit <NUM> and the second communication unit <NUM> to the electronic apparatus <NUM> in the active mode in which data can be transferred and connects the other of the first communication unit <NUM> and the second communication unit <NUM> to the electronic apparatus <NUM> in the sniff mode in which data is not transferred. In other words, the electronic apparatus <NUM> is connected to the first communication unit <NUM> in the active mode in which data can be transferred and is connected to the second communication unit <NUM> in the sniff mode having a shorter communication enabled period than that of the active mode and not used to transfer data. When the allocation processing unit <NUM> changes the destination of connection of the electronic apparatus <NUM> in the active mode in response to, for example, a change of the connection environment, the process of changing the destination of connection in the active mode can be instantaneously executed without performing a new paging process or authentication process because the electronic apparatus <NUM> has already been connected in the sniff mode to the communication unit to which the connection is switched.

The connection management unit <NUM> acquires the number of external apparatuses connected to the first communication unit <NUM> in the active mode and the number of external apparatuses connected to the second communication unit <NUM> in the active mode. In the connection state depicted in <FIG>, the first communication unit <NUM> is connected to two electronic apparatuses 200b and 200c in the active mode and the second communication unit <NUM> is connected to one electronic apparatus 200a in the active mode. The allocation processing unit <NUM> determines the destination of connection in the active mode of the electronic apparatus 200c, to which connection is established newly, to be the first communication unit <NUM> or the second communication unit <NUM> such that the number of external apparatuses connected to the first communication unit <NUM> in the active mode becomes equal to or smaller than the number of external apparatuses connected to the second communication unit <NUM> in the active mode. In the state in which the third electronic apparatus 200c establishes connection to the first communication unit <NUM> (state depicted in <FIG>), the number of external apparatuses connected to the first communication unit <NUM> in the active mode is greater than the number of external apparatuses connected to the second communication unit <NUM> in the active mode. Therefore, the allocation processing unit <NUM> determines that the connection destination of the electronic apparatus 200c in the active mode is the second communication unit <NUM> and accordingly determines to change the connection destination of the electronic apparatus 200c in the active mode from the first communication unit <NUM> to the second communication unit <NUM>.

<FIG> depicts a state in which the electronic apparatus 200c is connected to the first communication unit <NUM> and the second communication unit <NUM> simultaneously in the active mode. The first communication unit <NUM> in the connection state shown in <FIG> transmits a waiting instruction signal to the electronic apparatus 200c, and while the electronic apparatus 200c maintains the connection to the first communication unit <NUM> in the active mode, it operates in the page scan mode in which it waits for a connection request from the second communication unit <NUM>. The electronic apparatus 200c receives a connection request from the second communication unit <NUM> and establishes connection to the second communication unit <NUM> in the active mode. <FIG> depicts this state.

<FIG> shows a state in which the connection between the electronic apparatus 200c and the first communication unit <NUM> is changed to the sniff mode. The connection management unit <NUM> instructs the first communication unit <NUM> to change the mode of connection with the electronic apparatus 200c to the sniff mode. Receiving this instruction, the connection processing unit <NUM> transmits a change request to the electronic apparatus 200c to change the connection mode. Thereafter, the connection mode between the first communication unit <NUM> and the electronic apparatus 200c is changed to the sniff mode.

<FIG> shows a state in which the fourth electronic apparatus 200d is connected to the communication block <NUM>. The electronic apparatus 200d is wirelessly connected to the first communication unit <NUM> in the active mode and wirelessly connected to the second communication unit <NUM> in the sniff mode.

<FIG> depicts a state in which the third electronic apparatus 200c is disconnected from the communication block <NUM>. For example, if the user of the electronic apparatus 200c ends the game play and logs out from the device main body <NUM>, then the connection between the electronic apparatus 200c and the communication block <NUM> is cancelled.

After the connection between the electronic apparatus 200c and the communication device <NUM> is cancelled, the connection management unit <NUM> acquires the number of external apparatuses connected to the first communication unit <NUM> in the active mode and the number of external apparatuses connected to the second communication unit <NUM> in the active mode. In the connection state depicted in <FIG>, the first communication unit <NUM> is connected to the two electronic apparatuses 200b and 200d and the second communication unit <NUM> is connected to the one electronic apparatus 200a in the active mode. The allocation processing unit <NUM> executes an allocation process, triggered by the termination of wireless connection with the electronic apparatus 200c connected so far. In particular, the allocation processing unit <NUM> changes the connection destination of the electronic apparatus 200d in the active mode such that the number of external apparatuses connected to the first communication unit <NUM> in the active mode becomes equal to or smaller than the number of external apparatuses connected to the second communication unit <NUM> in the active mode. In the state depicted in <FIG>, since the number of external apparatuses connected to the first communication unit <NUM> in the active mode is greater than the number of external apparatuses connected to the second communication unit <NUM> in the active mode, the allocation processing unit <NUM> determines to change the connection destination of the electronic apparatus 200d in the active mode from the first communication unit <NUM> to the second communication unit <NUM>.

<FIG> shows a state in which the electronic apparatus 200d is connected to the second communication unit <NUM> in the active mode and connected to the first communication unit <NUM> in the sniff mode. In the variation, a paging process or an authentication process, which is required in the embodiment, is not necessary when the connection destination in the active mode is switched. Consequently, data communication between the electronic apparatus <NUM> and the communication device <NUM> is suitably maintained.

In this process, the control unit <NUM> changes the connection in the sniff mode between the electronic apparatus 200d and the second communication unit <NUM> to the connection in the active mode and then changes the connection in the active mode between the electronic apparatus 200d and the first communication unit <NUM> to the connection in the sniff mode. By following the procedure described above, data communication between the electronic apparatus 200d and the communication device <NUM> can be suitably maintained without being interrupted.

In the variation, when the connection between one of the first communication unit <NUM> and the second communication unit <NUM> and the electronic apparatus <NUM> is canceled, the control unit <NUM> may cancel the connection between the other of the first communication unit <NUM> and the second communication unit <NUM> and the electronic apparatus <NUM>. For example, the connection management unit <NUM> determines to cancel the connection with the electronic apparatus <NUM> when a duration of disconnection exceeds a predetermined period of time. By ensuring that, when the connection with one is determined to be canceled, the connection with the other is canceled, connection with the electronic apparatus <NUM> can be managed easily.

It is noted that while various techniques have been described individually for clarity of the description, an embodiment may employ any one or more of the techniques discussed above such that the various techniques are combinable in any permutation.

The present invention is applicable to a wireless communication technology.

Claim 1:
A communication device (<NUM>) comprising:
a first communication unit (<NUM>); and
a second communication unit (<NUM>) of a same type as that of the first communication unit,
the communication device being wirelessly connectable to a first external apparatus (200a, 200b, 200c, 200d), wherein
the first communication unit is configured to:
acquire, by a pairing process in advance, identification information for identifying the first external apparatus,
wait for a connection request from the first external apparatus, and
after accepting the connection request from the first external apparatus, transmit a signal for instructing the first external apparatus to establish a state in which the first external apparatus waits for a connection request from the second communication unit, and
the second communication unit is configured to transmit a connection request to the first external apparatus, and consequently wirelessly connect to the first external apparatus.