JP6742812B2 - Communication device, control method thereof, and program - Google Patents

Description

The present invention relates to a communication device, a control method thereof, and a program.

A connection with a terminal device via an external device such as a wireless router (external access point) (hereinafter, infrastructure connection) and a direct connection with the terminal device without an external device (hereinafter, P2P connection) are simultaneously performed ( In parallel, communication devices that can be established are known. Note that, as described above, the operation in which the two types of connections are simultaneously (parallelly) established and maintained is hereinafter referred to as simultaneous operation. When the connection with the external device is disconnected, such a communication device performs a process of searching for the external device in order to reconnect with the external device.

Patent Document 1 discloses a device that searches for an AP by a channel used for a direct connection with a terminal device when the connection with an access point (AP) is disconnected while operating simultaneously. ing. Further, Patent Document 1 discloses a device that searches for an AP by sequentially using available channels when an AP cannot be detected by searching for an AP using a channel used for direct connection with a terminal device. doing.

JP, 2014-216956, A

By the way, during the search of the external device which is executed when the infrastructure connection is disconnected in the state of simultaneous operation, for example, packet loss may occur in communication with the P2P-connected terminal device. Therefore, when the infrastructure connection is disconnected while operating simultaneously, for example, the control unit that can appropriately acquire the communication state between the P2P-connected terminal device and the communication device considers the communication state. It is desirable to search external devices. On the other hand, when the infrastructure connection is disconnected while the P2P connection is not made, it is not necessary to perform control in consideration of the communication state between the P2P connected terminal device and the communication device. Nevertheless, regardless of whether the infrastructure connection is disconnected while the P2P connection is not made or when the infrastructure connection is disconnected while the P2P connection is operating simultaneously, when the same control unit searches for the external device, the control is performed. The load is concentrated on the means. In recent years, with the multi-functionalization of communication devices as in Patent Document 1, it has been previously attempted to distribute the load on the control means in the communication device and improve the performance of the entire communication device when searching for external devices. More demanded.

Therefore, the present invention provides a communication device that can disperse the load on the process of searching for an external device and that can search the external device by a method according to the communication state of the communication device, a control method thereof, and a program. The purpose is to

In order to solve the above problems, a communication device according to the present invention is a communication device,
Of the channels usable by the communication device, a connection is established between the external device and the communication device in a first wireless network using a predetermined channel, and the terminal device and the communication device are used in the predetermined channel. Connection means for establishing a connection in the second wireless network of
And acquires the communication state between the terminal device and the communication device, a first control means for performing control based on the communication state,
A second control means different from the first control means,
Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel while There has been established in parallel, when the connection with the external device using the predetermined channel and the communication device is disconnected, the first control means, said first control means executes Searching the external device by a search method specified according to the communication state between the terminal device and the communication device among a plurality of possible search methods,
A connection in the first wireless network is established between the external device and the communication device using the predetermined channel, and the second device is connected to the terminal device and the communication device using the predetermined channel. When the connection between the external device and the communication device using the predetermined channel is disconnected in a state where the connection in the wireless network is not established, the second control unit causes the second control unit to communicate with the terminal device and the communication device. The external device is searched by a predetermined method regardless of the communication state with the external device.

ADVANTAGE OF THE INVENTION According to this invention, the load concerning the process which searches an external device can be disperse|distributed, and an external device search can be performed by the method according to the communication state of a communication device.

It is a figure which shows an example of a structure of a communication system. It is a figure which shows an example of the external appearance of a terminal device. FIG. 3 is a diagram showing an example of an external appearance of an MFP. FIG. 6 is a diagram illustrating an example of a screen displayed on the operation display unit of the MFP. It is a block diagram which shows the structure of a terminal device. FIG. 3 is a block diagram showing the configuration of the MFP. It is a figure which shows the wireless connection sequence in software AP mode. It is a figure which shows the wireless connection sequence in WFD mode. It is a figure which shows the wireless connection sequence in an infrastructure mode. It is a software block diagram which shows the domain structure of MFP. It is a flow chart which shows processing which a CPU of a main system performs by an I/F connection Mgr task. It is a figure which shows the flowchart which shows the process which a CPU of a main system performs by a control API task. It is a control flow diagram of a control API between the I/F domain and the NW subsystem. It is a figure which shows the table which shows the execution pattern of AP search. It is a flowchart which shows the infrastructure connection process performed by CPU of a NW subsystem. It is a flow chart which shows processing which a CPU of a main system performs by an I/F connection Mgr task. FIG. 9 is a diagram showing a sequence of reconnection processing performed when the connection between the MFP and the access point 400 is disconnected while the MFPs are simultaneously operating. FIG. 6 is a diagram showing a sequence of reconnection processing including a processing in which the MFP searches for an access point by a channel other than the channel used for the disconnected infrastructure connection.

Embodiments of the present invention will be illustratively described in detail below with reference to the drawings. However, the relative arrangement of the constituent elements, the display screen, and the like described in the present embodiment are not intended to limit the scope of the present invention to them unless otherwise specified.

(First embodiment)
The terminal device and the communication device of this embodiment will be described. In the present embodiment, a smartphone is exemplified as the terminal device. A smart phone is a multifunctional mobile phone equipped with a camera, a web browser, an electronic mail function, and the like in addition to the functions of the mobile phone. The terminal device to which the present invention can be applied is not limited to the smart phone, and may be any device that can communicate with the communication device described below. For example, a digital camera, a mobile terminal, a notebook PC, a tablet terminal, a PDA (Personal Digital Assistant), a music playback device, or the like can be applied as the terminal device. Further, in the present embodiment, a multi-function peripheral (hereinafter, referred to as an MFP) having a copy function, a FAX function, and a print function is illustrated as the communication device, but the communication device is not limited to this, and can communicate with a terminal device. Various devices can be applied as long as they are possible devices. For example, if it is a printer, an inkjet printer, a full-color laser beam printer, a monochrome printer, etc. can be applied. Further, not only a printer but also a copying machine, a facsimile machine, a smart phone, a mobile terminal, a notebook PC, a tablet terminal, a PDA, a digital camera, a music reproducing device, a storage, etc. are applicable. In addition, a single function printer (hereinafter, SFP) having a single function is also applicable.

<System configuration>
First, a system configuration for realizing the present embodiment will be described with reference to FIGS.

FIG. 1 is a diagram showing the configuration of the communication system of the present embodiment. This system includes an access point 400, a terminal device 200, and an MFP 300.

The terminal device 200 is the terminal device of the present embodiment. The MFP 300 is the communication device of this embodiment. Further, the MFP 300 and the terminal device 200 can communicate with each other through a WLAN (Wireless Local Area Network) connection via an access point 400 outside each device. Further, each of the MFP 300 and the terminal device 200 can operate as an access point. Therefore, for example, when one of the devices serves as an access point and the other device connects to the access point, the terminal device 200 and the MFP 300 can be directly connected to the wireless LAN without the access point 400. .. Further, since both the terminal device 200 and the MFP 300 have a WLAN function, it is possible to perform peer-to-peer (hereinafter, P2P) communication by executing the authentication process. When each device operates as an access point, each device forms a wireless LAN with a device of a communication partner, and periodically transmits a beacon signal. Further, when each device operates as an access point, each device determines a channel used for wireless communication, and performs authentication processing of connection information (password and the like) transmitted from a communication partner device.

A wireless communication system including an access point and clients will be described. The device serving as an access point first transmits a beacon signal. When the client receives the beacon signal, the client transmits a device search command (Probe Request frame) to the access point to search for and discover a device (communication partner device) as a communication partner. The device on the search side can attach various attributes (parameters) to the device search command. Particularly in the case of P2P wireless connection, the device search command includes information (P2P element) related to P2P wireless connection. Then, when the access point transmits a response command (Probe Response frame) with reference to the received device search command, it is possible to mutually discover the devices on the other side (device search (Discovery)). After that, a sequence such as confirmation of device information indicating the type of device and an IP address is executed, and then various applications such as printing can be executed.

FIG. 2 is a view showing the outer appearance of the terminal device 200.

The WLAN unit 201 is a unit for performing wireless communication by WLAN. The WLAN unit 201 is assumed to be capable of data (packet) communication in a WLAN system conforming to the IEEE 802.11 series, for example. That is, it is assumed that the WLAN unit 201 can execute communication by Wi-Fi (registered trademark), for example. The WLAN unit 201 has functions such as beacon detection processing and authentication processing for establishing a WLAN connection, and transmission of a print job to a communication device that has established a WLAN connection. Further, the WLAN unit 201 is capable of communication based on Wi-Fi Direct (WFD), software AP mode, ad hoc mode, infrastructure mode communication, and the like. Wi-Fi Direct (WFD)-based communication, software AP mode communication, and ad hoc mode communication are direct communication with a communication partner device (such as the MFP 300) operating as an access point (without passing through a relay device). ) Refers to communicating. In addition, the communication in the infrastructure mode refers to communication with a communication partner device via a relay device (access point 400 or the like) outside the terminal device 200 installed on the network.

The display unit 202 is, for example, a display including an LCD type display mechanism. Specifically, the display unit 202 displays a button icon and a software keyboard.

The operation unit 203 includes a touch panel type operation mechanism and detects an operation by the user. Specifically, the operation unit 203 detects an operation event that occurs when the user touches the button icon or the software keyboard displayed on the display unit 202.

The power key 204 is a hard key used when turning the power on and off.

FIG. 3 is a diagram showing an appearance of the MFP 300. The document table 301 is a glass-like transparent table on which a document read by a scanner (reading unit) is placed. The document cover 302 is a cover for holding the document when the scanner reads the document and for preventing the reading light emitted to the document during the reading from leaking to the outside.

The printing paper insertion slot 303 is an insertion slot into which various sizes of paper can be set. The sheets set in the printing sheet insertion port 303 are conveyed one by one to a printing unit (not shown), printed by the printing unit, and ejected from the printing sheet ejection port 304.

The operation display unit 305 includes keys such as a character input key, a cursor key, an enter key, and a cancel key, and an LED (light emitting diode), an LCD (liquid crystal display), and the like, and a user activates various functions as an MFP. Various settings can be accepted. The operation display unit 305 may be configured with a touch panel.

The WLAN antenna 306 is an antenna for communicating by WLAN.

FIG. 4 is a diagram showing an example of a screen displayed on the operation display unit 305. FIG. 4A is a screen (home screen) displayed on the operation display unit 305 when the MFP 300 is not performing an operation such as printing or scanning (idle state). The MFP 300 receives a key operation or a touch panel operation from the user while the home screen is displayed on the operation display unit 305 to display a cloud function menu display, various settings, and functions using the copy/scan or Internet communication. It is feasible. The operation display unit 305 can seamlessly display a screen different from the home screen shown in FIG. 4A by receiving the above-described operation. FIG. 4B is an example thereof. The MFP 300 executes a print or photo function or changes LAN settings by accepting a key operation or a touch panel operation by the user while the home screen shown in FIG. 4B is displayed on the operation display unit 305. It is possible. FIG. 4C is a screen displayed when the user performs an operation for executing LAN setting while the screen of FIG. 4B is displayed on the operation display unit 305. When “wireless LAN” on the screen shown in FIG. 4C is selected by the user operation, the MFP 300 receives from the user the valid/invalid setting of the infrastructure mode described later. At this time, the MFP 300 also accepts the setting of the connection partner (access point 400 or the like) of the MFP 300 in the infrastructure connection described later from the user. In addition, the MFP 300 accepts the valid/invalid setting of the WFD function from the user when “Wireless Direct” on the screen illustrated in FIG. 4C is selected by the user operation. Further, when the “wireless direct negotiation” on the screen shown in FIG. 4C is selected by the user operation, the MFP 300 receives from the user the setting for whether or not there is a negotiation setting to be described later.

FIG. 5 is a block diagram showing the configuration of the terminal device 200.

The terminal device 200 has a main board 501 that performs main control of the device itself and a WLAN unit 517 that performs WLAN communication.

In the main board 501, a CPU (central processing unit) 502 is a system control unit, and controls the entire terminal device 200 by executing programs stored in the ROM 503 and activating hardware. It should be noted that the processing to be described later executed by the terminal device 200 is executed under the control of the CPU 502.

The ROM 503 stores a control program executed by the CPU 502, an embedded operating system (OS) program, and the like. In this embodiment, each control program stored in the ROM 503 controls software such as scheduling and task switch under the control of the embedded OS stored in the ROM 503.

The RAM 504 is a memory including an SRAM (Static Random Access Memory) and a DRAM (Dynamic Random Access Memory). The RAM 504 stores data such as program control variables, setting values registered by the user, management data of the terminal device 200, and the like. The RAM 504 is provided with various work buffer areas.

The image memory 505 is composed of a memory such as a DRAM, and temporarily stores the image data received via the WLAN unit 517 and the image data read from the data storage unit 513 for processing by the CPU 502.

The non-volatile memory 512 is configured by a memory such as a flash memory and stores data that should be retained even when the power is turned off.

It should be noted that the memory configuration held by the terminal device 200 is not limited to this mode, and the number, characteristics, storage capacity, etc. may be appropriately changed depending on the use or purpose. For example, the image memory 505 and the RAM 504 may be shared, or data backup may be performed in the data storage unit 513. Further, in the present embodiment, a DRAM is used as the image memory 505, but another storage medium such as a hard disk (HDD) or a non-volatile memory may be used.

The data conversion unit 506 analyzes data of various formats and performs data conversion such as color conversion and image conversion on image data.

The telephone unit 507 realizes telephone communication by controlling a telephone line and processing voice data input/output via the speaker unit 514.

The operation unit 508 controls a signal output from the operation unit 204 and detects an operation by the user.

A GPS (Global Positioning System) 509 acquires position information such as the current latitude and longitude of the terminal device 200.

Display unit 510 electronically controls the content of the screen displayed on display unit 202, and can display various input operation screens, operation status screens of MFP 300, status status screens, and the like on display unit 202. it can.

The camera unit 511 has a function of electronically recording and encoding an image input via the lens. Image data corresponding to the image captured by the camera unit 511 is stored in the data storage unit 513.

The speaker unit 514 realizes a function of inputting or outputting a voice for a telephone function and other functions such as alarm notification.

The power supply unit 515 is a portable battery and controls power supply to the inside of the terminal device 200. The power supply state of the terminal device 200 includes a dead battery state in which the battery has no remaining capacity, a power off state in which the power key 205 is not pressed, a normally activated start state, and a power consumption that is higher than the activated state. There is a small power saving state.

The WLAN unit 517 is a unit for performing wireless communication by WLAN. The WLAN unit 517 is assumed to be capable of data (packet) communication in a WLAN system conforming to the IEEE 802.11 series, for example. That is, the WLAN unit 517 is assumed to be able to execute Wi-Fi (registered trademark) communication, for example. The WLAN unit 517 has functions such as beacon detection processing and authentication processing for establishing a WLAN connection, and transmission of a print job to a communication device that has established a WLAN connection. With the WLAN unit 517, the terminal device 200 performs data communication with other devices such as the MFP 300. The WLAN unit 517 converts data into a packet and transmits the packet to another device, or conversely, restores a packet from another external device to the original data and transmits it to the CPU 502. The WLAN unit 517 is connected to the main board 501 via the bus cable 516.

Various components (503 to 515 and 517) in the main board 501 are connected to each other via a system bus 519 managed by the CPU 502.

FIG. 6 is a block diagram showing the configuration of the MFP 300.

The MFP 300 has a main board 601 that performs main control of the apparatus itself, and a WLAN unit 616 that performs WLAN communication.

In the main board 601, a CPU 602 is a system control unit and controls the entire MFP 300 by executing a program stored in the ROM 603 and activating hardware. Further, the CPU 602 grasps the apparatus state of the MFP 300 and executes each processing described later. Further, the CPU 602 also has a role of executing processing (for example, processing such as print control and scan control) other than the AP search described later in order to control the entire MFP 300.

The ROM 603 stores a control program executed by the CPU 602, an embedded OS program, and the like. In this embodiment, each control program stored in the ROM 603 performs software control such as scheduling and task switch under the control of the embedded OS stored in the ROM 603.

The RAM 604 is a memory composed of SRAM, DRAM and the like. The RAM 604 stores data such as program control variables, setting values registered by the user, management data of the MFP 300, and the like. The RAM 604 is provided with various work buffer areas.

The non-volatile memory 605 includes a memory such as a flash memory and stores data that should be retained even when the power is turned off.

The image memory 606 is configured by a memory such as a DRAM and stores image data received via the WLAN unit, image data processed by the encoding/decoding processing unit 611, and the like.

Further, similarly to the memory configuration held by the terminal device 200, the memory configuration held by the MFP 300 is not limited to this mode, and the number, characteristics, storage capacity, etc. may be changed as appropriate according to the application or purpose. May be.

The data conversion unit 608 analyzes data in various formats and converts image data into print data.

The reading control unit 607 controls the reading unit 609 (for example, a CIS image sensor (contact image sensor)) to optically read an image on a document. Then, the reading control unit 607 outputs an image signal obtained by converting the read image into electrical image data. At this time, the reading control unit 607 may output various image signals after performing various image processing such as binarization processing and halftone processing.

The operation display unit 610 corresponds to the operation display unit 305, and receives activation of various functions as the MFP and various settings from the user.

The encoding/decoding processing unit 611 performs encoding/decoding processing and enlargement/reduction processing on image data (JPEG, PNG, etc.) handled by the MFP 300.

The paper feeding unit 613 holds a recording medium for printing. Note that a plurality of paper feeding units 613 may be prepared in order to hold a plurality of types of recording media in one device.

The print control unit 614 can control the paper feeding unit 613 and supply the recording medium to the printing unit 612. When a plurality of paper feed units 613 are prepared, the print control unit 614 can control from which paper feed unit of the plurality of paper feed units 613 the paper is fed.

The print control unit 614 performs various image processing such as smoothing processing, print density correction processing, and color correction on the image data to be printed, and then outputs it to the printing unit 612.

The printing unit 612 is an inkjet printer that prints an image by ejecting ink supplied from an ink tank from a print head. The printing unit 612 does not have to be an inkjet printer, and may be, for example, a laser beam printer or the like. Further, the print control unit 614 periodically reads the information of the printing unit 612 and updates the information of the RAM 604. Specifically, the print control unit 614 updates status information such as the remaining amount of the ink tank and the state of the print head. Since the WLAN unit 616 corresponds to the WLAN unit 201, its description is omitted. The WLAN unit 616 is connected to the main board 601 via a bus cable 615. Note that the terminal device 200 and the MFP 300 can perform Wi-Fi Direct (WFD)-based communication by a WLAN unit included in each device, and have a software access point (software AP) function. The software AP function is a function for causing a device that executes the function to operate as a software-based access point.

The NW subsystem 620 is a subsystem for reducing the control load of the CPU 602, and controls input/output control related to network communication. The NW sub CPU 621 is a CPU for executing input/output control related to network communication. The NW sub CPU 621 is a CPU for reducing the control load of the CPU 602 by executing a part of the processing that can be executed by the CPU 602 instead of the CPU 602. Therefore, in the present embodiment, the range of processing executed by the NW sub CPU 621 is narrower than the range of processing executed by the CPU 602. Further, for example, the performance regarding the processing speed and the cache capacity of the CPU 602 is higher than that of the NW sub CPU 621. Further, the NW sub CPU 621 has a limited accessible area as compared with the CPU 602, and for example, in order to acquire the device information of the MFP 300 and the like, it is necessary to acquire from the CPU 602 by inter-CPU communication. A control code executed by the NW sub CPU 621 is stored in a part of the RAM 604, and the control code is DMA (Direct Memory Access) transferred from the RAM 604 to the RAM 622 in the boot sequence of the CPU 602. The control code is a code for the 621 to execute input/output control related to network communication. The modules (621, 622, 623) in the NW subsystem are interconnected via a local bus 624 that is separated from the main system bus 618. Since the NW subsystem 620 takes on the function of a layer particularly close to the hardware layer among the functional modules related to network communication, the influence of the load status of other modules on the main board is minimized and the independence is high. Realizes network control.

The WLAN unit 616 has the same function as the WLAN unit included in the terminal device 200, and a description thereof will be omitted. The WLAN unit 616 is connected to the UHOST module 623 in the NW subsystem 620 via the USB bus 625. Note that, hereinafter, the systems on the main board 601 other than the NW subsystem 620 are referred to as main system subsystems.

Various components (602 to 614, 616 to 617, 620) in the main board 601 are connected to each other via a system bus 618 managed by the CPU 602.

<P2P (Peer to Peer) mode>
In order to establish a P2P connection in WLAN communication, the MFP 300 according to the present embodiment operates in a P2P mode (software AP mode or Wi-Fi Direct (WFD) mode). In this embodiment, the P2P connection refers to a mode in which devices directly wirelessly connect to each other without an external device. When the MFP 300 connects to the terminal device 200 without using an external device, the P2P mode is set as the communication mode of the MFP 300. Even if the P2P connection between the MFP 300 and the terminal device 200 is disconnected or the power of the MFP 300 is turned off, the MFP 300 continues to operate in the P2P mode unless the communication mode of the MFP 300 is changed due to a setting change or the like. In the present embodiment, changing the setting of the P2P mode corresponds to turning on/off the WFD function of the MFP 300.

The WFD is a standard established by the WiFi Alliance. The terminal device 200 and the MFP 300, which are WFD compatible devices, have a software access point (soft AP) function for operating as an access point. Therefore, the terminal device 200 and the MFP 300 can be directly wirelessly connected to each other by the WFD without using another access point. Which of the WFD-compatible devices that communicate by WFD operates as the soft AP is determined according to a sequence called Group Owner Negotiation (hereinafter, negotiation). Specifically, which device operates as the soft AP is determined among the devices based on the magnitude of the intent value preset in each device. Hereinafter, the device that plays the role of the soft AP is particularly referred to as GroupOwner. In the present embodiment, it is assumed that channels 1 to 13 in the 2.4 GHz frequency band defined by the Wi-Fi standard are used for communication between devices. GroupOwner plays a role of determining a channel used for communication between devices. Therefore, the negotiation can be said to be a process of specifying whether or not the device operates as a device that determines a channel used for communication between the devices. The channels used by MFP 300 are not limited to channels 1 to 13. For example, the MFP 300 can use channels 1 to 13 and 36 to 140 when communication is possible using the frequency bands of 2.4 GHz and 5 GHz.

In a communication system including devices that communicate in each mode, a device on the search side searches for and finds a device (communication partner device) that is a communication partner using a device search command (for example, a Probe Request frame). The device on the search side can attach various attributes (parameters) to the device search command. In particular, at the time of searching for connection by the P2P method, the device search command includes information (P2P element) regarding the P2P wireless connection. When an attribute is specified in the search command, the device that responds to the device search command is normally specified by the mode specification of the device on the search side and the prerequisite specifications (Wi-Fi for WFD). It is recommended to give maximum response to interpretable attributes within the range. Further, even if the information (including the above attributes) accompanying the device search command cannot be interpreted, the device that responds to the device search command can respond based on only the information that can be interpreted.

The wireless connection sequence in each mode will be described below with reference to FIGS. 7 and 8.

FIG. 7 is a diagram showing a wireless connection sequence in the software AP mode. The processing executed by each device in this sequence is realized by the CPU of each device reading the various programs stored in the memory such as the ROM of each device into the RAM and executing the programs. In addition, it is assumed that the present sequence is started in a state in which the terminal device 200 operates as a client and the MFP 300 operates as a software AP, and the MFP 300 transmits a beacon signal. When a predetermined operation for operating as software AP is received from the user, MFP 300 starts operating as software AP. The predetermined operation is, for example, an operation of selecting a predetermined icon for starting the operation as the software AP on the LAN setting screen.

First, in step S<b>701, the terminal device 200 sequentially transmits a device search command by using channels available to the terminal device 200, and searches for a device serving as the software AP.

Subsequently, in S702, when the MFP 300 receives the device search command transmitted from the terminal device 200, the MFP 300 transmits a device search response, which is a response to the device search command, to the terminal device 200. It should be noted that the MFP 300 does not transmit a device search response to a device search command transmitted on a channel other than a channel that the MFP 300 can use. For example, assuming that the channel that can be used by the MFP 300 is the fourth channel, the MFP 300 does not send a response command to the device search request command sent using the first channel. Therefore, after transmitting the device search command using the first channel, terminal device 200 transmits the device search request command using the second channel when there is no response from MFP 300 for a certain period of time. The terminal device 200 repeats the above-described trial while incrementing the channel number to be used. Then, for example, when the terminal device 200 receives the device search command transmitted using the fourth channel, the MFP 300 transmits a device search response to the terminal device 200. As a result, the terminal device 200 discovers the MFP 300. The channel used for transmitting the device search response is subsequently determined as the channel used for communication between the terminal device 200 and the MFP 300. That is, the channel used for communication between the terminal device 200 and the MFP 300 is determined by the MFP 300 operating as the soft AP.

Subsequently, in S703, a known wireless connection establishment process is executed between the terminal device 200 and the MFP 300. Specifically, processing such as connection request transmission, connection request authentication, and IP address allocation is performed. The commands and parameters transmitted and received in the process of establishing the wireless connection between the terminal device 200 and the MFP 300 may be those defined by the Wi-Fi standard, and description thereof will be omitted here. ..

FIG. 8 is a diagram showing a wireless connection sequence in the WFD mode. The processing executed by each device in this sequence is realized by the CPU included in each device reading the various programs stored in the memory such as the ROM included in each device into the RAM and executing the programs. Further, the present process is supposed to be started when a predetermined operation for establishing a connection by WFD is received from the user in a state where each device is running a predetermined application for executing the WFD function. To do.

First, in step S801, the terminal device 200 transmits a device search command, and searches for a device compatible with the WFD function as a communication partner device.

Subsequently, in step S802, the MFP 300 transmits a device search response, which is a response to the received device search command, to the terminal device 200. As a result, the terminal device 200 discovers the MFP 300 as a device compatible with the WFD function. After the terminal device 200 discovers the MFP 300, a process of exchanging information regarding services and functions that can be provided by each device may be performed between the devices.

Subsequently, in S803, a negotiation process is performed between the terminal device 200 and the MFP 300. The negotiation process is a process of determining a role (GroupOwner and client) in P2P communication by using a predetermined setting value held by each device. When the role of each device is determined by the negotiation process, parameters for performing Wi-Fi Direct communication are exchanged between the devices (parameter exchange phase). The parameter exchange phase corresponds to automatic exchange of wireless LAN security parameters by Wi-Fi Protected Setup, for example. After the negotiation is performed, the GroupOwner determines the channel used for the subsequent communication.

After that, in S804, each device executes a wireless connection establishment process based on the exchanged parameters.

Note that the MFP 300 may be able to accept from the user the setting as to whether or not to execute negotiation in the wireless connection sequence in the WFD mode. When the MFP 300 is set not to execute the negotiation, the MFP 300 operates as the GroupOwner itself.

Note that, hereinafter, the connection for communicating in the P2P mode (connection with the terminal device 200 not via the access point 400) is referred to as P2P connection.

<About infrastructure mode>
As described above, the infrastructure mode is a mode in which the communication devices (for example, the terminal device 200 and the MFP 300) communicate with each other via the external device (for example, the access point 400) that controls the network. When MFP 300 connects to terminal device 200 via access point 400, infrastructure mode is set as the communication mode of MFP 300. Even if the connection between the MFP 300 and the access point 400 is disconnected or the power of the MFP 300 is turned off, the MFP 300 continues to operate in the infrastructure mode unless the communication mode of the MFP 300 is changed due to a setting change or the like.

FIG. 9 is a diagram showing a wireless connection sequence in the infrastructure mode. The processing executed by each device in this sequence is realized by the CPU included in each device reading the various programs stored in the memory such as the ROM included in each device into the RAM and executing the programs.

First, in step S901, the terminal device 200 sequentially transmits a device search command using channels available to the terminal device 200, and searches for a device serving as the software AP.

Subsequently, in S902, when the access point 400 receives the device search command transmitted from the terminal device 200, the access point 400 transmits a device search response command, which is a response to the device search command, to the terminal device 200. As described in the description of S702, the access point 400 transmits the device search response command only to the device search command transmitted by the channel that can be used by itself. As a result, the terminal device 200 discovers the access point 400. The channel used for transmitting the device search response command is subsequently determined as the channel used for communication between the terminal device 200 and the access point 400. That is, the channel used for communication in the infrastructure mode is determined by the access point 400.

Subsequently, in S903, a known wireless connection establishment process is executed between the terminal device 200 and the access point 400. Specifically, processing such as connection request transmission, connection request authentication, and IP address allocation is performed. As in the P2P mode, the commands and parameters transmitted and received in the process of establishing the wireless connection between the terminal device 200 and the MFP 300 may be those defined by the Wi-Fi standard. The description of is omitted.

In S904 to S906, the same processing as S901 to S903 is executed between the MFP 300 and the access point 400. At this time, the access point 400 transmits the device search response command to the MFP 300 using the channel used for communication with the terminal device 200. That is, the access point 400 communicates with the MFP 300 and the terminal device 200 using the same channel.

As a result, the MFP 300 and the terminal device 200 are connected via the access point 400, and communication between the MFP 300 and the terminal device 200 via the access point 400 becomes possible.

Note that, hereinafter, the connection for communication in the infrastructure mode (connection with the terminal device 200 via the access point 400) is referred to as infrastructure connection.

<About simultaneous operation mode>
The MFP 300 can execute the communication in the infrastructure mode and the communication in the P2P mode at the same time (in parallel), and can perform the operation in the infrastructure mode and the operation in the P2P mode at the same time (in parallel). I shall. Therefore, the MFP 300 can simultaneously (in parallel) establish a connection for communication in the infrastructure mode and a connection for communication in the P2P mode. Hereinafter, a connection for communication in the infrastructure mode (connection with the terminal device 200 via the access point 400) is referred to as an infrastructure connection. A connection for communicating in the P2P mode (connection with the terminal device 200 not via the access point 400) is called a P2P connection. Further, hereinafter, to operate while maintaining the infrastructure connection and the P2P connection at the same time (in parallel) is referred to as a simultaneous operation. When the MFP 300 executes the operation as the infrastructure mode and the operation as the P2P mode at the same time (in parallel), the infrastructure mode is set as the communication mode of the MFP 300. Even if the connection between the MFP 300 and the terminal device 200, the connection between the MFP 300 and the access point 400 is disconnected, or the power of the MFP 300 is turned off, the MFP 300 operates in the simultaneous operation mode unless the communication mode of the MFP 300 is changed. Keep doing

In the present embodiment, the MFP 300 can accept from the user the setting as to whether or not to execute negotiation in the wireless connection sequence in the WFD mode, and if the setting to execute negotiation is made, it will not operate simultaneously. To do.

<Channel decision sequence in simultaneous operation mode>
Communication in the infrastructure mode and communication in the P2P mode are performed using a specific frequency band (specific channel). Therefore, in both the communication in the infrastructure mode and the communication in the P2P mode, it is necessary to first determine the channel used for communication/connection between each device before communication is started. In a mode in which a plurality of channels are simultaneously assigned to one wireless IC chip for communication, the configuration of each device that performs communication and the processing executed by each device become complicated. Therefore, for example, when the MFPs 300 operate simultaneously, it is desirable that a common channel be used in communication in each mode. That is, it is desirable that the MFP 300 uses only one channel even when operating simultaneously. Therefore, in the present embodiment, the WLAN unit 616 has only one wireless IC chip that realizes communication through a predetermined channel, and the MFP 300 does not communicate using a plurality of channels at the same time.

As described above, if the MFP 300 operates as the GroupOwner or the soft AP, the MFP 300 can freely determine the channel used for the P2P connection. However, the channel used for infrastructure connection is determined by the access point 400. Therefore, when the MFPs 300 operate simultaneously, it is preferable that the channel used for infrastructure connection determined by the access point is determined as the channel used for P2P connection.

In the present embodiment, it is assumed that the infrastructure connection and the P2P connection use 1 to 13 channels in the 2.4 GHz frequency band defined by the Wi-Fi standard. However, the number of channels is increased in different frequency bands, or the number of channels is limited to 1 to 11 even in the same frequency band due to restrictions on frequency bands in some countries or regions. Therefore, the channels used by MFP 300 are not limited to channels 1 to 13. Further, for example, in the IEEE 802.11a standard, 36 to 140 channels in the frequency band of 5 GHz can be used. Further, when the MFP 300 uses the frequency bands of 2.4 GHz (1 to 13 channels) and 5 GHz (36 to 140 channels), the number of available channels is larger than that in the case of using one of the frequency bands. Become. Therefore, when both frequency bands are used, the number of channels for transmitting the device search command to the access point increases.

<About reconnection processing>
For example, the wireless connection between the MFP 300 and the access point 400 may be disconnected due to a disconnection factor such as a poor radio wave condition or a change in the setting of the channel used for the connection. In this case, the MFP 300 tries to reconnect with the access point 400. Here, a process (reconnection process) executed by the MFP 300 to reconnect to the access point 400 will be described.

FIG. 17 is a diagram showing a sequence of a reconnection process performed when the connection between the MFP 300 and the access point 400 is disconnected while the MFPs 300 are simultaneously operating. The processing executed by each device in this sequence is realized by the CPU included in each device reading the various programs stored in the memory such as the ROM included in each device into the RAM and executing the programs. Further, it is assumed that the processing indicated by this sequence is started while MFP 300 is operating as software AP.

First, in step S1701, the MFP 300 and the access point 400 establish a wireless connection, and the MFP 300 and the communication partner device establish an infrastructure connection via the access point 400, in the same manner as the processing described in the description of FIG. Here, it is assumed that the channel used for the connection (infrastructure connection) between MFP 300 and access point 400 is determined as the p-th channel.

In step S1702, the MFP 300 and the terminal device 200 establish a P2P connection in the same manner as the process described in the description of FIG. Since the channel used for the connection between the MFP 300 and the access point 400 is the p-th channel, the channel used for the connection between the MFP 300 and the terminal device 200 (P2P connection) is also determined as the p-th channel. ..

Subsequently, in step S1703, the connection (infrastructure connection) between the MFP 300 and the access point 400 is disconnected due to the disconnection factor described above. That is, the connection between the MFP 300 and the access point 400 is disconnected while the MFP 300 is establishing the infrastructure connection with the communication partner device via the access point 400 and the P2P connection with the terminal device 200 in parallel. .. At this time, specifically, the access point 400 transmits a disconnection command to the MFP 300.

In FIG. 17, it is assumed that the P2P connection between the terminal device 200 and the MFP 300 is maintained even if the connection between the MFP 300 and the access point 400 is disconnected in S1703.

Subsequently, in step S1704, the MFP 300 uses the p-th channel which is used in the disconnected infrastructure connection and is currently used in the P2P connection in order to rediscover and connect to the access point 400. The point 400 is searched. That is, the MFP 300 transmits the device search request command to the access point 400 using the p-th channel. At this time, the MFP 300 may execute the transmission of the device search request command a plurality of times. In addition, hereinafter, the search for the access point 400 is referred to as an AP search.

Subsequently, in step S1705, the access point 400 receiving the device search request command transmits a device search response command, which is a response to the device search request command, to the MFP 300. After that, a publicly-known connection process is executed in S1706 to restart the connection between the MFP 300 and the access point 400.

Thereby, even if the connection between MFP 300 and access point 400 is once disconnected, MFP 300 can use the p-th channel to reestablish the infrastructure connection.

However, for example, when the access point 400 autonomously changes the used channel to a relatively idle channel after disconnection by referring to the congestion state of the surrounding radio wave environment, the access point 400 uses the channel. The channel changes from before the disconnect. In addition, a change in the channel used by the access point 400 for connection may be the cause of disconnection in the first place.

When the channel used by the access point 400 is changed, the access point 400 responds only to the device search request command transmitted by the changed channel. Therefore, the MFP 300 cannot reconnect to the access point 400 by the AP search using the channel used for the disconnected infrastructure connection (that is, the p-th channel). Therefore, the MFP 300 according to the present embodiment executes an AP search using the channel used for the disconnected infrastructure connection. As a result, if reconnection cannot be performed, the MFP 300 other than the channel used for the disconnected infrastructure connection is not used. Perform AP search by channel.

FIG. 18 is a diagram showing a sequence of a reconnection process including a process in which the MFP 300 searches for the access point 400 using a channel other than the channel used for the disconnected infrastructure connection. The processing executed by each device in this sequence is realized by the CPU included in each device reading the various programs stored in the memory such as the ROM included in each device into the RAM and executing the programs. Further, it is assumed that the processing indicated by this sequence is started while MFP 300 is operating as software AP.

The processing of S1801 to S1804 is the same as the processing of S1701 to S1704, and thus the description thereof is omitted. In step S1803, it is assumed that the channel used by the access point 400 is changed from the p-th channel to the q-th channel after the connection between the MFP 300 and the access point 400 is disconnected.

Since the channel used by the access point 400 has been changed as described above, the MFP 300 cannot detect the access point 400 in the AP search using the p-th channel in S1804. Therefore, when the MFP 300 repeats the AP search using the p-th channel a predetermined number of times without detecting the access point 400, the MFP 300 performs an AP search using a channel other than the p-th channel in S1805. Specifically, the MFP 300 performs an AP search by sequentially using all available channels from the first channel. It should be noted that MFP 300 may execute transmission of the device search request command a plurality of times in the AP search using each channel. At this time, the device search request may not be transmitted on all channels available to MFP 300. That is, just before the connection between the MFP 300 and the access point 400 is disconnected, the device search request may be transmitted using at least a channel other than the channel used in the communication between the MFP 300 and the access point 400. ..

Since the channel used by access point 400 is the qth channel, when MFP 300 performs the AP search using the qth channel, access point 400 transmits a device search response command to MFP 300 in step S1806.

After that, in S1807, the MFP 300 disconnects the P2P connection with the terminal device 200 once in order to switch the channel used for the P2P connection. Note that the timing of disconnecting the P2P connection with the terminal device 200 is not limited to after S1806. For example, after the connection between the MFP 300 and the access point 400 is disconnected, processing of data communicated in the P2P mode is completed. It may be the timing of the start.

Thereafter, in steps S1808 and 1109, a publicly-known connection process is executed to restart the connection between the MFP 300 and the access point 400 (infrastructure connection) and the connection between the MFP 300 and the terminal device 200 (P2P connection).

The commands and parameters transmitted/received when the wireless connection is restarted between the devices may be those defined by the Wi-Fi standard, and the description thereof will be omitted here.

In the above-described embodiment, if the channel used by access point 400 has not been changed after the connection between MFP 300 and access point 400 has been disconnected, MFP 300 reconnects to access point 400 by the AP search in step S1804. In this case, the MFP 300 omits the process of S1805.

As a result, the MFP 300 can reconnect to the access point 400 even if the channel used by the access point 400 is changed due to some reason after the connection between the MFP 300 and the access point 400 is disconnected.

However, as described above, the MFP 300 of this embodiment does not use a plurality of channels at the same time (in parallel). Therefore, when performing an AP search using a channel other than the channel used for the infrastructure connection (the channel currently used for the P2P connection), the MFP 300 needs to temporarily stop the communication in the P2P mode. In this case, in communication in the P2P mode, there is a possibility that a packet loss or a transmission packet delay may occur. Note that packet loss means that a packet transmitted by the terminal device 200 using the channel used for P2P connection is not received by the MFP 300 and lost because the channel other than the channel used for P2P connection was used by the MFP 300. It means to end up. In addition, the transmission packet delay means that when the packet cannot be transmitted to the terminal device 200 because the MFP 300 uses a channel other than the channel used for the P2P connection, the channel used for the P2P connection becomes available. It means that the packet transmission is delayed.

If the communication in the P2P mode is network communication via the TCP layer, the lost packet is retransmitted even if a packet loss occurs, but if it is network communication via the UDP layer, it is lost. Packets will not be retransmitted. Therefore, depending on the behavior of the OS, the driver, or the application of the terminal device 200, packet loss may occur, so that the communication partner device in the P2P mode communication may not be detected or the application may not be used.

Therefore, in the reconnection process shown in FIG. 18, the AP search by the channel currently used for P2P connection is executed first. As a result, if the channel used by the access point has not been changed after disconnection of the infrastructure, the access point can be detected without causing packet loss or transmission packet delay in communication in the P2P mode.

Note that the reconnection process described above is merely an example, and in the present embodiment, in addition to the reconnection process described above, various reconnection processes depending on the state of the MFP 300 as shown in FIG. 14 described later are executed. ..

FIG. 10 shows a domain block diagram of software executed by the CPU 602 and the NW sub CPU 621. The software of 1000 to 1030 is stored in the ROM 603, and the software of 1031 to 1034 is stored in the memory of the WLAN unit 616. The software of 1000 to 1019 is executed by the CPU 602, and the software of 1020-1030 is executed by the NW sub CPU 621. Further, the software of 1031 to 1034 is assumed to be executed by the CPU included in the WLAN unit 616. The main system 1000 is entirely configured by a μItron standard-compliant embedded OS 1001 executed by the CPU 602, a SYS domain 1002 including system tasks that control state transitions related to the entire apparatus, and functional domains.

The NW subsystem 620 is a part of the main system 1000, and includes an embedded OS 1020 executed by the NW sub CPU 621, a SYS domain 1021 that controls state transitions in the NW subsystem, and network-related functional domains. ..

The I/F domain 1010 executed by the CPU 602 includes an interface control block group for each service protocol linked with the application domain 1005. A WSD (Web Service For Device) 1014 is software for executing printing, scanning, and FAX based on WSD. An IPP (Internet Printing Protocol) 1015 is software for executing printing, scanning, and FAX based on IPP. The I/F application Mgr task 1016 is software for grasping the execution state of each service by managing the resources (number) of the HTTP task 1017 assigned to each service protocol such as WSD 1014 and IPP 1015. The CPU 602 performs bidirectional data communication between the CPUs with the NW subsystem 620 by the socket API 1019 via the HTTP task assigned to each service protocol according to each service protocol. Connection mode information indicating infrastructure mode/WFD mode/software AP mode is added to the parameters of each socket as interface information.

The CPU 602 handles the transmission/reception packet via the socket API by the TCP/IP task 1026 and the UDP task 1027 in the NW subsystem 620. Then, the CPU 602 routes the transmission/reception packet via the socket API, and passes it to the infrastructure controller 1024, the P2P controller 1025, and the data controller 1028 according to the interface information. After that, the CPU 602 converts the format of the transmission/reception packet via the socket API into the packet data and the data according to the communication standard such as 802.11 by the WLAN chip controller 1029. Finally, the CPU 602 divides the converted data into 512-byte units, which is the USB packet size, and makes the WLAN unit 616 reach the WLAN unit 616 by DMA control by the USBHOST driver task 1030.

In the WLAN unit, there are two modules (data control module 1032, waveform control module 1033) for control conforming to the USB module 1031 and 802.11 standard, which are responsible for data transmission and reception between the units. There is also a WLAN RF module 1034 for transmitting and receiving a single radio antenna in the WLAN unit.

Further, as software commonly executed by the CPU 602 and the NW subsystem 620, there are a socket API for packet data transmission/reception and a control API 1018. The control API 1018 is an API for changing the setting of each control module in the NW subsystem, instructing an execution command, notifying a network state change, and the like. The I/F connection Mgr 1011/simultaneous operation connection sequencer 1012/AP search handler 1013 in the I/F domain issues a command according to the status in the I/F domain and the status of the peripheral domains via the control API. It

The NW sub CPU 621 handles the command issued from each element in the I/F domain by the NW sub Mgr 1022. The NW sub CPU 621 uses the infrastructure controller 1024 and the P2P controller 1025 to perform start/end control of the infrastructure mode and the P2P mode and a setting change instruction according to the type of command to be handled. Further, in the present embodiment, when the MFPs 300 are simultaneously operating and a connection process in which the device state and the peripheral domain state are taken into consideration is required, the simultaneous operation connection sequencer 1012 executes the connection by the CPU 602 alone. On the other hand, in the present embodiment, when the MFPs 300 are not operating simultaneously and the connection processing in consideration of the device status and the peripheral domain status is not required, the NW sub connection sequencer 1023 executes the connection by the NW sub CPU 621 alone. .. For example, when reconnection processing that is not caused by a user operation (UI operation on the main body or the like) is performed, the NW sub connection sequencer 1023 continues to execute the AP search in the background. Note that the case where the reconnection process that is not caused by the user operation is performed is, for example, a case where the connection between the MFP 300 operating in the infrastructure mode and the access point is disconnected. Further, at this time, the NW sub-connection sequencer 1023 executes the AP search by all the channels available to the MFP 300. With such a configuration, even when the channel used by the AP is changed, the MFP 300 and the AP can be reconnected.

In this embodiment, various commands are communicated between the CPU 602 and the NW sub CPU 621. Here, the inter-CPU communication between the CPU 602 and the NW sub CPU 621 will be described.

FIG. 12 is a diagram showing a flowchart showing the processing executed by the CPU 602 by the control API task. The control API task is a task that executes inter-CPU communication between the CPU 602 and the NW sub CPU 621, and is responsible for command transmission and status notification event reception (command reception and status notification event delivery from the NW sub CPU side). There is. Commands and parameters in command transmission, and event and notification information in event reception are exchanged in an event driven format by a shared RAM secured in a part of RAM 604 accessible by both CPUs and an inter-CPU interrupt signal. The process shown in this flowchart is realized by the CPU 602 reading a program corresponding to the control API 1018 stored in a memory such as the ROM 603 into the RAM 604 and executing the program.

First, the CPU 602 returns from the WAIT task and executes the control API task when a command message is issued from each task in the I/F domain 1010 or a status notification event interrupt is generated from the NW sub CPU 621 ( S1200). After that, the CPU 602 determines whether or not there is a command to be transmitted to the NW sub CPU 621 (S1201). For example, when transmitting a command to the NW sub CPU 621 in S1105/S1112/S1121/S1126, which will be described later, the CPU 602 sets the command and parameter to be transmitted in the shared RAM (S1202). After that, the CPU 602 transmits the command set in the NW sub CPU 621 (S1203). The NW sub CPU 621 receives each transmitted command by the NW sub Mgr 1022, then distributes it to each task of the NW sub connection sequencer 1023, the infrastructure controller 1024, and the P2P controller 1025, and executes a process according to the command.

On the other hand, when there is no command to be transmitted to the NW sub CPU 621, the CPU 602 executes each process according to the notification received from the NW sub CPU 621.

When the NW sub CPU 621 executes the infrastructure connection processing in response to the infrastructure connection command transmitted in S1105 or S1121 described later, the CPU 602 receives the infrastructure connection completion notification from the NW sub CPU 621 (S1210). The CPU 602 acquires information via the shared RAM (S1270), and stores the channel number of the successfully connected infrastructure, the assigned IP address, and the like included in the acquired information (S1211). After that, the CPU 602 generates an infrastructure connection completion event referenced in S1106 and S1122 (S1212).

In addition, the connection between the MFP 300 and the access point 400 may be disconnected while the MFP 300 is in infrastructure connection with the communication partner device via the access point 400. In this case, the NW sub CPU 621 notifies the CPU 602 of a disconnection event indicating that the infrastructure connection has been disconnected (S1220). After that, if there is information notified from the NW sub CPU 621 in the notification of the disconnection event, the CPU 602 acquires the information via the shared RAM (S1270). At this time, if there is no information notified from the NW sub CPU 621, the process of S1270 is omitted. After that, the CPU 602 issues the infrastructure reconnection Mseg referred to in the reconnection processing described later (S1221).

Further, in response to the P2P activation command transmitted in S1112 or S1126 described later, the NW sub CPU 621 activates the P2P controller 1025 to operate the MFP 300 as a software AP. As a result, a beacon signal including the SSID name (printer SSID name) serving as the identifier of the MFP 300 operating as the software AP is periodically broadcast from the WLAN unit 616. Then, when the NW sub CPU 621 receives the device search request (ProbeRequest) from the terminal device 200 that has detected the beacon, the PW controller 1025 transmits a device search response (ProbeResponse) to the terminal device 200. The terminal device 200 that has received the device search response transmits a connection request to the MFP 300 operating as the software AP. When the NW sub CPU 621 receives the connection request and the password authentication is successful, the NW sub CPU 621 transmits the connection permission to the terminal device 200, so that the P2P connection between the MFP 300 and the terminal device 200 is established.

In the present embodiment, the MFP 300 permits connection with up to five terminal devices 200 in a P2P connection in which the MFP 300 is a GroupOwner. In order to manage the number of terminal devices in P2P connection (the number of P2P connections), the CPU 602 receives a P2P device connection notification during P2P connection (S1230). Then, the MFP 300 receives the P2P device disconnection notification (S1240) from the NW sub CPU 621 when the P2P connection is disconnected (the terminal device 200 is disconnected). After that, if there is information notified from the NW sub CPU 621, the CPU 602 acquires the information via the shared RAM (S1270). At this time, if there is no information notified from the NW sub CPU 621, the process of S1270 is omitted. Then, the CPU 602 adds or subtracts the value of the number of P2P connections stored in the memory such as the RAM according to the received notification (S1231 and S1241), and issues the connection Mseg and the disconnection Mseg (S1232 and S1242).

When the CPU 602 issues the connection Mseg, the I/F application Mgr task cooperates with the application domain 1005 and each of the service protocols 1014-1015, and executes the connection processing in the application/service layer following the connection in the physical layer. (Not shown).

Further, when the CPU 602 issues the disconnection Mseg, the I/F application Mgr task executes a process of releasing the HTTP resource assigned to the terminal device 200 whose P2P connection has been released (not shown). The P2P connection number information and the HTTP resource information will be referred to in the reconnection process after disconnection of the infrastructure in the simultaneous operation, which will be described later.

When the WLAN unit 616 receives the device search response (ProbeResponse) from the access point 400 as a result of the AP search, the CPU 602 receives the AP search completion notification from the NW sub CPU 621 (S1250). After that, the CPU 602 acquires information via the shared RAM (S1270). Then, the CPU 602 stores the MAC address of the detected access point 400 and the number of the communication channel that has been successfully detected, which are included in the acquired information, in the internal RAM (S1251) and issues an AP search completion event to the simultaneous connection sequencer task. .. (S1252)
When the WLAN unit 616 receives the response of the connection permission response from the access point 400 as a result of the AP search, the CPU 602 receives the AP JOIN completion notification from the NW sub CPU 621 (S1260). After that, the CPU 602 acquires information via the shared RAM (S1270). Then, the CPU 602 saves the IP address allocated from the access point 400 and the communication channel number used for infrastructure connection, which is included in the acquired information, in the internal RAM (S1261) and issues an AP JOIN completion event (S1262).

Next, a sequence of network connection/disconnection/reconnection will be described.

FIG. 11 is a flowchart showing the processing executed by the CPU 602 by the I/F connection Mgr 1011. The process of powering on, the process of disconnecting and reconnecting, and the process of changing parameters will be described in order centering on the connection process of the wireless network. The process shown in this flowchart is realized by the CPU 602 reading a program corresponding to the I/F connection Mgr 1011 stored in a memory such as the ROM 603 into the RAM 604 and executing the program.

[Processing at power-on]
Hereinafter, a connection process executed when the power of the MFP 300 returns from the off state to the on state will be described. The following process is a process of restoring the connection state of the MFP 300 before the MFP 300 is turned off.

When the MFP 300 is powered on, a power-on Mseg is issued from the SYS domain to each domain. The CPU 602 processes the power-on Mseg issued to the I/F domain by the connection Mgr 1011 (S1101).

After that, the CPU 602 refers to the user setting value held in the non-volatile memory (not shown) in the MFP 300, and determines whether the MFP 300 is in the simultaneous operation mode (S1102).

When determining that the MFP 300 is not in the simultaneous operation mode, the CPU 602 determines whether the MFP 300 is in the infrastructure mode (S1103). When determining that the MFP 300 is in the infrastructure mode, the CPU 602 executes a connection process for establishing an infrastructure connection. Specifically, first, the CPU 602 acquires network parameters (SSID, authentication method, password, etc.) for executing infrastructure connection, which are stored in the nonvolatile memory (S1104). This network parameter corresponds to the parameter for connecting to the access point that was connected to the infrastructure at the previous power off. Then, the CPU 602 issues an infrastructure connection command using the parameter acquired by the control API task as a command argument to the NW sub CPU 621 via the control API task (S1105). The infrastructure connection command is a command for causing the NW sub CPU 621 to execute reconnection processing for reestablishing the infrastructure connection according to the acquired parameters. That is, CPU 602 specifies to cause NW sub CPU 621 to execute the reconnection process when MFP 300 is in the infrastructure mode at power-on.

Upon receiving the infrastructure connection command, the NW sub CPU 621 executes, by the NW sub connection sequencer 1023, a sequence process including an access point search process and a connection process with the detected access point. Specifically, the NW sub CPU 621 executes the processing of S1804 to S1806 and S1808 in the reconnection processing shown in FIG.

Subsequently, the CPU 602 determines whether or not the connection with the access point is completed by the reconnection process executed by the NW sub CPU 621 (S1106). Specifically, the CPU 602 determines whether an infrastructure connection completion event via the control API task has occurred. When the CPU 602 determines that the connection with the access point is not completed, the CPU 602 executes the process of S1106 again. On the other hand, when the CPU 602 determines that the connection with the access point is completed, the CPU 602 acquires the connection number such as the number of the channel that has been successfully connected and the IP address assigned to the MFP 300 from the access point after the connection is completed (S1107). Save to non-volatile memory.

As described above, when the MFP 300 is in the infrastructure mode at the time of power-on, the CPU 602 can restart the infrastructure connection disconnected at the time of power-off at the time of power-on.

If the CPU 602 determines in S1103 that the MFP 300 is not in the infrastructure mode (when the MFP 300 is in the P2P mode), the CPU 602 validates the access point in the MFP 300 used in the P2P mode. Specifically, first, CPU 602 determines a channel to be used for communication (communication in the P2P mode) via the access point in MFP 300 (S1110). It should be noted that the channel number to be used is set to a default value, and the channel number 3 is used here. Note that the channel is not limited to this number, and a channel with an arbitrary number may be used.

Subsequently, the CPU 602 acquires network parameters (SSID, password, channel number used, etc.) used for connection with the access point in the MFP 300 (S1111). Then, the CPU 602 issues an AP start command using the acquired parameter as a command argument to the NW sub CPU 621 via the control API task (S1112). The AP activation command is a command for causing the NW sub CPU 621 to execute a process of activating a connectable software AP according to the acquired parameters.

The NW sub CPU 621 that has received the AP start command refers to the network parameter included in the AP start command and specifies the channel number (No. 3) used for P2P connection. Then, the NW sub CPU 621 validates the access point in the MFP 300, and periodically transmits a beacon signal including the SSID of the access point in the MFP 300 using the third channel. After that, the NW sub CPU 621 waits for a device search request from the terminal device 200, and when a device search request is received, transmits a device search response to the terminal device 200 to establish a P2P connection between the MFP 300 and the terminal device 200. To do.

As described above, when the MFP 300 is in the P2P mode at power-on, the CPU 602 can restart the P2P connection disconnected at power-off at power-on.

Further, as described above, when the MFP 300 is in the infrastructure mode at the time of power-on and when the MFP 300 is in the P2P mode at the time of power-on, the NW sub CPU 621 executes the reconnection process. With such a configuration, it is possible to prevent the load on the reconnection processing from being applied to the CPU 602.

On the other hand, when the CPU 602 determines in S1102 that the MFP 300 is in the simultaneous operation mode, the CPU 602 establishes the infrastructure connection and validates the access point in the MFP 300 to execute the simultaneous operation. Specifically, in S1120 to S1123, the CPU 602 performs the same processing as S1104 to S1107 to establish a connection between the MFP 300 and the access point. After that, in S1124 to S1126, the CPU 602 performs the same process as in S1110 to S1112 to validate the access point in the MFP 300. Note that in step S1124, the CPU 602 identifies the number of the channel that has been successfully connected to the access point, and uses the channel of the identified number as the channel to be used for communication (communication in the P2P mode) via the access point in the MFP 300. decide. Then, the CPU 602 executes the same processing as S1111 and S1112 (S1125, S1126), thereby activating the access point in the MFP 300 that can be connected through the channel determined in S1124.

In this manner, the CPU 602 can restart the P2P connection and the infrastructure connection that were disconnected at the time of power-off when the MFP 300 is in the simultaneous operation mode at the time of power-on.

Further, as described above, when MFP 300 is in the simultaneous operation mode at the time of power-on, NW sub CPU 621 executes reconnection processing. This is because both the infrastructure connection and the P2P connection are disconnected at the time of power-on, so an application responsible for processing data communicated by each connection is not executed, and the replay corresponding to the status of the MFP 300 main body is not executed. This is because the connection process need not be executed. Since the NW sub CPU 621 executes the reconnection process, it is possible to suppress the load of the reconnection process on the CPU 602.

The wireless network connection process of the power-on process has been described above. At the time of power-on, the CPU 602 needs to perform a startup process of the entire device using an engine domain, a UI domain, or the like. Therefore, in the mode in which the CPU 602 executes the reconnection process at the time of power-on, not only the connection process sequence becomes complicated, but also the startup process takes a long time due to the lack of resources required for the startup process of the entire device, and the convenience for the user is impaired. Get lost. Therefore, in the present embodiment, the NW sub CPU 621 executes the reconnection process at the time of power-on, the load of the wireless connection sequence is distributed, and the CPU 602 can smoothly perform the startup process.

In the present embodiment, in the LAN setting change process and the infrastructure reconnection process described later, when the MFP 300 is in the simultaneous operation mode, the reconnection process according to the device state of the MFP 300 is executed. Therefore, the CPU 602 capable of promptly acquiring the device status of the MFP 300 executes the reconnection process. On the other hand, in the power-on process, NW sub CPU 621 executes the reconnection process even when MFP 300 is in the simultaneous operation mode. This is because in the power-on process, even if the MFP 300 is in the simultaneous operation mode, both the P2P connection and the infrastructure connection are disconnected, so that the common channel is used for the P2P connection and the infrastructure connection. This is because no problem occurs when reconnecting. Therefore, priority is given to reducing the load on the CPU 602, and the NW sub CPU 621 is made to execute the reconnection processing.

[LAN setting change processing]
Hereinafter, the connection process executed when the user instructs the LAN setting change by operating the operation display unit 610 for input on the LAN setting change screen of FIG. 4C, will be described. It should be noted that the instructed LAN setting change is, for example, valid/invalid setting of the infrastructure mode, valid/invalid setting of the WFD function, and change setting of the connection information (SSID or password) of the soft AP valid when the MFP 300 is in the P2P mode. , Negotiation settings, etc. In addition, for example, the setting of the encryption method used for communication in the infrastructure mode may be instructed.

When the user instructs to change the LAN setting, the UI domain 1004 issues the LAN setting change Mseg to the I/F connection Mgr 1011. Therefore, the CPU 602 starts the LAN setting change process (S1130).

Subsequently, the CPU 602 refers to a user setting value held in a non-volatile memory (not shown) in the MFP 300 and determines whether the MFP 300 is in the simultaneous operation mode (S1131). When the CPU 602 determines that the MFP 300 is not in the simultaneous operation mode, it issues a LAN setting change command to the NW sub CPU 621 via the control API task (S1132). The LAN setting change command is a command for causing the NW sub CPU 621 to change the LAN setting instructed by the user.

Upon receiving the LAN setting change command, the NW sub CPU 621 delivers the execution processing message to the infrastructure controller 1024 or the P2P controller 1025 according to the change content of the LAN setting instructed by the user. As a result, the NW sub CPU 621 executes a process of applying the LAN setting change content instructed by the user.

On the other hand, when the CPU 602 determines that the MFP 300 is in the simultaneous operation mode, the CPU 602 executes the processing of S1142 and subsequent steps, which will be described later.

Although details will be described later, if the MFP 300 is in the simultaneous operation mode, the CPU 602 executes the LAN setting change processing, and if the MFP 300 is not in the simultaneous operation mode, the NW sub CPU 621 executes the LAN setting change processing. The LAN setting changing process may be accompanied by, for example, changing the communication band or changing the channel used for communication. Further, in the simultaneous operation mode, the MFP 300 executes the communication in the infrastructure mode and the communication in the P2P mode in the same communication band and the same channel. Therefore, in the LAN setting change process when the MFP 300 is operating in the simultaneous operation mode, it may be necessary to confirm the consistency of the parameters and the consistency between the parameter change timing and the device operation state. Therefore, in the present embodiment, the CPU 602, which can finely understand the device state of the MFP 300 and the execution state of the application being executed in the MFP 300, executes the LAN setting change process in the state where the MFP 300 is operating in the simultaneous operation mode. I shall.

[Infrastructure reconnection processing]
Hereinafter, reconnection processing executed when the connection between the MFP 300 and the access point 400 is disconnected (the infrastructure connection is disconnected) while the MFP 300 is connected to the communication partner device via the access point 400 via the infrastructure. Will be described.

When the connection between the MFP 300 and the access point 400 is disconnected, the NW sub CPU 621 detects disconnection of the infrastructure connection. After that, the NW sub CPU 621 notifies the CPU 602 of a disconnection event indicating that the infrastructure connection has been disconnected. Upon receiving the disconnection event, the CPU 602 handles the event notification by the control API 1018 (S1220). As a result, the infrastructure reconnection Mseg is issued (S1221), so that the CPU 602 executes the reconnection processing after S1140.

The CPU 602 attempts to restart the infrastructure connection in response to the issuance of the infrastructure reconnection Mseg (S1140). First, the CPU 602 refers to a user setting value stored in a non-volatile memory (not shown) in the MFP 300 and determines whether the MFP 300 is in the simultaneous operation mode (S1141).

If the CPU 602 determines that the MFP 300 is not in the simultaneous operation mode, the CPU 602 executes the processes of S1104 and subsequent steps, similarly to the process at power-on. As a result, when the MFP 300 is not in the simultaneous operation mode, the NW sub CPU 621 executes reconnection processing for infrastructure connection.

On the other hand, when the CPU 602 determines that the MFP 300 is in the simultaneous operation mode, the CPU 602 executes the process of S1142 and thereafter to execute the reconnection process of the infrastructure connection. That is, if the connection between MFP 300 and access point 400 is disconnected while MFP 300 is not in the simultaneous operation mode, reconnection processing is executed by NW sub CPU 621. Then, when the connection between the MFP 300 and the access point 400 is disconnected while the MFP 300 is in the simultaneous operation mode, the CPU 602 executes the reconnection process.

The CPU 602 first refers to the status information of the MFP 300 (S1142). Specifically, the CPU 602 determines the number of P2P devices (devices currently in P2P connection with the MFP 300) managed by the I/F application Mgr task, and the usage status of application services (HTTP resources) executed in the simultaneous operation mode. (The number of items used, etc.)

Subsequently, the CPU 602 identifies which Type of connection sequence is to be executed, in accordance with the referred state information of the MFP 300 (S1143). Note that, in the case of the process of S1143 in the LAN setting change process, the LAN setting change content instructed by the user is also referred to in specifying the connection sequence.

Subsequently, the CPU 602 acquires network parameters (SSID, authentication method, password, etc.) for executing infrastructure connection, which are stored in the non-volatile memory (S1144). This network parameter corresponds to a parameter for connecting to the access point (access point 400) to be reconnected. In the case of the process of S1144 in the LAN setting change process, the network parameter corresponds to the parameter for connecting to the access point designated by the user.

After that, the CPU 602 activates the simultaneous operation connection sequencer task, and executes the infrastructure connection process based on the acquired parameter and the specified Type connection sequence (S1145). Details of this processing will be described later.

As a result, the reconnection process is executed after considering the operation status of the application for each I/F type. Even in the LAN setting change process, depending on the setting contents, it is possible to promptly return the feedback for the user operation (instruction), and it is possible to make a detailed response according to the use case.

FIG. 13 is a flowchart showing the infrastructure connection processing executed by the CPU 602. The process shown in this flowchart is realized by the CPU 602 reading the program corresponding to the simultaneous operation connection sequencer 1012 stored in the memory such as the ROM 603 into the RAM 604 and executing the program. The process shown in this flowchart corresponds to the process after the simultaneous operation connection sequencer task is activated in S1145.

Thereafter, the CPU 602 executes the Type connection sequence specified in S1143. It should be noted that Type 1 to Type 3 are connection sequences specified in the LAN setting change process according to the setting change contents instructed by the user. Type 4 is a connection sequence specified in the infrastructure reconnection process. Although four types are shown as the connection sequence in the present description, other type connection sequences are prepared according to the setting change contents instructed by the user, the state of the MFP 300 in the infrastructure reconnection process, and the like. Is also good.

When the setting change content instructed by the user is only the parameter change setting that does not involve connection processing, the CPU 602 proceeds to step S1310 in order to specify the connection sequence of Type 1 in step S1143. Parameter change settings without connection processing are negotiation settings, settings of encryption methods used for communication in the infrastructure mode, and the like. Then, the CPU 602 issues a parameter set command to the controller on the NW subsystem side corresponding to the parameter change via the control API (S1131). As a result, the NW sub CPU 621 performs a process of applying the setting change content instructed by the user, using each controller.

When the controller 602 on the NW subsystem side needs to be restarted, more specifically, the P2P controller needs to be restarted, the CPU 602 proceeds to step S1320 in order to identify the connection sequence of Type 2 in step S1143. The case where the P2P controller needs to be restarted corresponds to, for example, the case where the setting change content instructed by the user is the change setting of the connection information (SSID, password, etc.) of the software AP that is valid in the P2P mode of the MFP 300. To do. The CPU 602 issues a P2P controller STOP command to the NW sub CPU 621 (S1321), stops the MFP 300 from operating as the software AP, and then issues a parameter set command to the NW sub CPU 621 (S1322). The parameter set command is a command for applying the setting change content instructed by the user. As a result, for example, the SSID name and password of the soft AP that is valid when the MFP 300 is in the P2P mode are changed. After that, the CPU 602 issues a P2P activation command to the NW sub CPU 621 (S1323), and restarts the operation of the MFP 300 as the software AP.

If the setting change content instructed by the user is the reconnection process of the infrastructure connection disconnected due to the change of the password of the access point 400, the CPU 602 proceeds to S1330 to identify the connection sequence of Type3 in S1143. move on. At this time, the cause of disconnection of the infrastructure connection is the password change, and the communication channel number used for the infrastructure connection is not changed. Therefore, even if the infrastructure connection is restarted, the channel used in the P2P mode communication is not changed, and therefore the CPU 602 does not need to stop the P2P mode communication. Therefore, the CPU 602 stops only the operation of the infra controller by issuing the infra controller STOP command to the NW sub CPU 621 (S1331). After that, the CPU 602 specifies to execute the AP search by the communication channel used in the disconnected infrastructure connection (the communication channel currently used in the P2P connection) (S1332). At this time, the AP search cycle is 200 msec, and the retry limit number is 3 times. When executing the AP search, the CPU 602 activates the AP search handler and issues an AP search command including information on the channel number used for the AP search to the infrastructure controller 1024 on the NW subsystem side via the control API. To do. As a result, the AP search is executed, and the device search request (ProbeRequest) is wirelessly output from the WLAN unit 616 through the communication channel used in the disconnected infrastructure connection. Then, the access point 400 that receives the Probe Request wirelessly outputs a device search response (ProbeResponse).

The CPU 602 waits for the processing of S1250 to S1252 to be executed and the AP search completion event to be issued during the Wait task (S1334) for a predetermined time (50 msec). After the Wait, the CPU 602 determines whether or not the access point 400 is detected. Specifically, the CPU 602 determines whether an AP search completion event has been issued during the Wait task (S1335). If the CPU 602 determines that the access point 400 is not detected, it waits again in step S1334. On the other hand, when determining that the access point 400 is detected, the CPU 602 issues an APJOIN command to the NW sub CPU 621 using the SSID name/password of the detected access point 400 as an argument (S1336). When the NW sub CPU 621 receives the APJOIN command, the device connection request to the access point 400 detected by the AP search is wirelessly output from the WLAN unit 616. The wirelessly output data includes an authentication method and a password, and the access point 400 determines whether the received information matches the internally held authentication method and password, If they match, the response of the connection permission response is wirelessly output.

The CPU 602 determines whether or not the processes of S1260 to S1262 have been executed and the AP JOIN completion event has been issued, and when determining that the AP JOIN completion event has been issued, the activation of the AP search handler ends (S1338). .. As a result, the CPU 602 completes the simultaneous operation connection sequencer task processing.

When executing the processing of S1143 in the infrastructure reconnection processing, the CPU 602 proceeds to S1310 in order to specify the connection sequence of Type4.

Since the disconnected connection is an infrastructure connection, the CPU 602 first transmits a command for stopping the operation of the infrastructure controller 1024 to the NW sub CPU 621 (S1341). After that, the CPU 602 determines an AP search execution pattern according to the status information of the MFP 300 acquired in S1142 (S1342). In this embodiment, four patterns as shown in FIG. 14 are prepared as AP search execution patterns.

The AP search sequence table shown in FIG. 14 is a table referred to during AP search. In this table, AP search sequence number (SeqNo), search type (Type), search cycle (cycle), and retry limit number of times (Retry) are defined for each execution pattern. The sequence number indicates the order of each AP search in each execution pattern. The CPU 602 executes each AP search corresponding to each number in order of the sequence number. The search type (Type) indicates the type of each AP search. When the search type is fixed, the CPU 602 executes the AP search using the communication channel stored in the RAM 604 and used in the disconnected infrastructure connection (the communication channel currently used for the P2P connection). When the search type is ALL, CPU 602 executes an AP search by using all communication channels available to MFP 300 in order from the smallest numbered channel. It should be noted that MFP 300 may execute transmission of the device search request command a plurality of times in the AP search using each channel. Further, at this time, CPU 602 does not have to use all the communication channels that can be used by MFP 300, and at least use the communication channels other than the communication channel used in the disconnected infrastructure connection. The order of the channels used at this time is not particularly limited. For example, the CPU 602 first executes the AP search using the channel currently used for the P2P connection, and then uses the channels in order from the first channel. Then, the AP search may be executed. When using the frequency bands of 2.4 GHz (1 to 13 channels) and 5 GHz (36 to 140 channels), the CPU 602 preferentially uses a channel corresponding to one of the frequency bands (for example, 5 GHz) to perform an AP search. May start. The search cycle (cycle) indicates a cycle for executing the AP search corresponding to each sequence number. The retry limit number (Retry) indicates the number of times to retry the AP search corresponding to each sequence number when the access point cannot be found. When the number of retries is Forever, the CPU 602 repeats the AP search retries with the corresponding sequence numbers until the AP search handler is terminated by finding an access point or the like. If the number of retries is P2PBusy, the CPU 602 repeats the AP search retry of the corresponding sequence number until the communication in the P2P mode is completed, and then performs the AP search of the next sequence number.

The pattern (a) is an execution pattern selected in the reconnection process of the infrastructure connection whose disconnection factor is that the password for connecting to the access point 400 has been changed. When the pattern (a) is selected, the CPU 602 executes the AP search up to three times at a cycle of 200 msec by the communication channel used in the disconnected infrastructure connection (the communication channel currently used for the P2P connection). To do. The reason why only the AP search with the fixed search type is executed is that the channel used by the access point 400 is likely not changed when the password change is the disconnection factor of the infrastructure connection. Further, when the channel used by the access point 400 is not changed, the access point can be immediately detected by the AP search whose search type is fixed. Therefore, the CPU 602 executes the AP search with a short cycle of 200 msec and a small number of retry limits.

The pattern (b) is an execution pattern selected in the reconnection process when the MFP 300 is not executing the communication in the simultaneous operation mode and the P2P mode (the P2P communication state is the idle state). That is, the pattern (b) is an execution pattern selected in the reconnection process when the number of P2P devices connected is 0. When the pattern (b) is selected, the CPU 602 first uses the communication channel used in the disconnected infrastructure connection (the communication channel currently used for the P2P connection) to perform an AP search up to three times in a cycle of 10 seconds. To execute. After that, when the access point cannot be detected by the AP search with the sequence number 1, the CPU 602 sequentially uses all the communication channels that can be used by the MFP 300 in a cycle of 10 seconds until the AP is detected until the AP is detected. To execute. The AP search whose search type is ALL is executed after the AP search whose search type is fixed, so that the access point can be detected even if the channel used by the access point is changed after the disconnection of the infrastructure. .. Further, the CPU 602 first executes an AP search whose search type is fixed. By adopting such a form, if the channel used by the access point has not been changed after disconnecting the infrastructure, the access point can be detected without causing packet loss or transmission packet delay in communication in the P2P mode as much as possible. You can

The pattern (c) is an execution pattern selected in the reconnection process when the MFP 300 is executing communication in the simultaneous operation mode and the P2P mode (P2P communication state is operation (Busy) state). When the pattern (c) is selected, the CPU 602 first performs communication in the P2P mode at a cycle of 10 seconds by the communication channel used in the disconnected infrastructure connection (the communication channel currently used for the P2P connection). The AP search is executed until the end. After that, when the access point cannot be detected by the AP search with the sequence number 1, the CPU 602 sequentially uses all the communication channels that can be used by the MFP 300, and executes the AP search up to three times in a cycle of 2 sec. To do. After that, when the access point cannot be detected by the AP search with the sequence number 2, the CPU 602 sequentially uses all the communication channels that can be used by the MFP 300, and in the cycle of 30 sec, the CPU search proceeds until the AP is detected. To execute. If a channel other than the communication channel currently used for P2P connection is used during the communication in the P2P mode, problems such as packet loss and transmission packet delay are likely to occur. Therefore, in pattern (c), an AP search with a fixed search type is executed until the communication in the P2P mode ends. Further, the cycle of the AP search for the sequence number 3 is delayed from the cycle of the AP search for the sequence number 2. As a result, it is possible to suppress frequent occurrence of packet loss and transmission packet delay due to AP search whose search type is ALL being executed in a short cycle, even in a state in which the access point cannot be detected. ..

Pattern (d) is an execution pattern selected in the reconnection process when the MFP 300 is executing communication in the simultaneous operation mode and the infrastructure mode (the infrastructure communication state is the operation (Busy) state). For example, there is a case where the infrastructure connection is disconnected due to radio wave interference or the like while executing communication in the infrastructure mode. The case where the infrastructure connection is disconnected but the infrastructure communication state is in the operation (Busy) state corresponds to such a case. In such a case, it is necessary to promptly restore the communication in the infrastructure mode. Therefore, in the pattern (d), each AP search is executed in a shorter cycle than the patterns (b) and (c).

Note that, for example, as the state of the MFP 300, a state in which a P2P device is connected but communication in the P2P mode is not executed, or even if communication in the P2P mode is executed, the communication cycle is intermittent with a cycle of several tens of seconds. It is also conceivable that the situation will be carried out at. Therefore, the execution pattern is not limited to the above four patterns, and a finer pattern may be prepared according to the use case. Further, the retry period and the number of retries in the AP search of each pattern are not limited to the above values as long as the above-described relationship is satisfied between the AP searches of each sequence number.

As described above, in the present embodiment, when the infrastructure connection is disconnected while the MFP 300 is operating in the simultaneous operation mode, different reconnection processing is executed depending on the communication state or connection state of the MFP 300. As a result, an appropriate reconnection process is executed according to the communication state and connection state of the MFP 300, and it is possible to detect the access point without causing problems such as packet loss and transmission packet delay as much as possible. Can be improved.

Further, in the present embodiment, the reconnection process executed when the infrastructure connection is disconnected while the MFP 300 is operating in the simultaneous operation mode is executed by the CPU 602 instead of the NW sub CPU 621. Since the CPU 602 is responsible for controlling the entire apparatus, the range of accessible information is wider and the access speed to the information is faster than that of the NW sub CPU 621. Further, the NW sub CPU 621 needs to acquire the information on the communication state and connection state of the MFP 300 from the CPU 602 through inter-CPU communication, for example. Therefore, CPU 602 can execute a process in accordance with the information on the communication state and connection state of MFP 300 more quickly than NW sub CPU 621. In the case as described above, the CPU 602 executes the reconnection process, thereby executing the appropriate reconnection process according to the communication state or connection state of the MFP 300.

After determining the execution pattern in S1342, the CPU 602 activates the AP search handler and starts the AP search based on the determined execution pattern (S1343).

After that, the CPU 602 waits until the AP search completion event is issued by executing the processes of S1250 to S1252 during the Wait task (S1344) of the predetermined time (50 msec). After the Wait, the CPU 602 determines whether or not the access point 400 is detected. Specifically, the CPU 602 determines whether an AP search completion event has been issued during the Wait task (S1345). If the CPU 602 determines that the access point 400 is not detected, it waits again in step S1334. On the other hand, when the CPU 602 determines that the access point 400 has been detected, whether or not the channel number for which the access point 400 has been successfully detected has been changed from the channel number used in the previous infrastructure connection with the access point 400. Determine whether. (S1346) That is, the CPU 602 determines whether or not the channel number of which the access point 400 has been successfully detected matches the channel number currently used for P2P connection.

If the channel number of which the access point 400 has been successfully detected does not match the channel number currently used for P2P connection, the channel currently used for P2P connection is switched, so the P2P connection is temporarily disconnected, You will then need to reconnect. However, if the P2P connection is disconnected during the communication in the P2P mode, the data communicated between the P2P device and the MFP 300 may be lost. Therefore, when the CPU 602 determines in S1346 that the channel number of which the access point 400 has been successfully detected does not match the channel number currently used for P2P connection, whether communication in the P2P mode is being performed. It is determined whether or not (S1347). When the CPU 602 determines that communication in the P2P mode is being performed, the CPU 602 performs the process of S1344 again. On the other hand, when the CPU 602 determines that communication in the P2P mode is not being performed, the CPU 602 transmits a P2PSTOP command to the NW sub CPU 621 to release the P2P connection of the MFP 300 (S1348). After that, the CPU 602 performs the processes of S1349 to S1351. The processes of S1349 to S1351 are the same as S1336 to S1338, and thus the description thereof will be omitted.

After that, the CPU 602 issues a P2P parameter set command including the number of the communication channel successfully connected to the access point 400 and a P2P activation command to the NW sub CPU 621 (S1351, S1352). As a result, the CPU 602 restarts the software AP of the MFP 300. The disconnected P2P connection is restarted by accepting a connection request from the terminal device 200 again. The channel used for P2P connection at this time is a channel for which the access point 400 has been successfully detected and connected.

On the other hand, if the CPU 602 determines in S1346 that the channel number of which the access point 400 has been successfully detected matches the channel number currently used for P2P connection, it determines the channel currently used for P2P connection. No need to switch. Therefore, the CPU 602 performs the processes of S1354 to S1356. The processing of S1354 to S1356 is the same as that of S1336 to S1338, and thus the description thereof is omitted. As described above, in this embodiment, the CPU 602 executes the infrastructure connection process when the MFP 300 is in the simultaneous operation mode. Unlike the NW sub CPU 621, the CPU 602 can confirm the device state of the MFP 300 and the content of the received LAN setting change, and execute the connection sequence corresponding to the confirmed information.

FIG. 15 is a flowchart showing the infrastructure connection processing executed by the NW sub CPU 621. The process shown in this flowchart is realized by the NW sub CPU 621 reading a program corresponding to the NW sub connection sequencer 1023 stored in the memory such as the ROM 603 into the RAM 622 and executing the program. The process shown in this flowchart is started when an infrastructure connection command is transmitted to the NW sub CPU 621 in S1105 and S1121.

First, the NW sub CPU 621 receives an infrastructure connection command. After that, the NW sub CPU 621 initializes the channel (search Ch) used for searching the access point 400 to 1 (S1502). After that, the NW sub CPU 621 searches for an access point having the SSID name passed in the argument of the infrastructure connection command (S1503). Specifically, the NW sub CPU 621 issues an AP search Mseg to the infrastructure controller 1024, and causes the WLAN unit 616 to wirelessly output a device search request (ProbeRequest) by the search Ch. Then, the NW sub CPU 621 waits for a device search response from the access point for a predetermined time (100 msec).

After that, the NW sub CPU 621 determines whether or not the access point has been successfully detected by the AP search in S1503 (S1504). Specifically, the NW sub CPU 621 determines whether or not the device search response has been received from the access point. When the NW sub CPU 621 determines that the access point has not been successfully detected, the NW sub CPU 621 determines a channel to be used for the next AP search. Specifically, the search Ch is incremented (S1508).

Then, it is determined whether or not the channel number determined as the channel to be used for the next AP search is the upper limit value. That is, the NW sub CPU 621 determines whether or not the AP search has been executed using all available channels (S1509). When the NW sub CPU 621 determines that the channel number is the upper limit value, it waits for a predetermined time (500 msec) (S1510). This is because the NW sub CPU 621 is temporarily released so that other tasks in the NW subsystem can be executed. After that, the NW sub CPU 621 performs the process of S1502 again. On the other hand, when the NW sub CPU 621 determines that the channel number is not the upper limit value, the NW sub CPU 621 performs an AP search in S1503 using the channel determined in S1508. That is, if the NW sub CPU 621 fails to detect the access point, the NW sub CPU 621 sequentially performs the AP search by sequentially using the available channels.
On the other hand, when the NW sub CPU 621 determines that the access point has been successfully detected, it issues an AP JOIN Mseg to the infrastructure controller 1024 with the communication channel number, SSID name, encryption method, password, etc. as arguments (S1506). Further, at this time, the NW sub CPU 621 transmits an AP search completion notification to the CPU 602, and stores the MAC address of the detected access point and the communication channel number that has been successfully detected in the shared RAM. When the AP JOIN Mseg is issued, the WLAN unit 616 wirelessly outputs a device connection request to the access point detected by the AP search in S1503. Upon receiving the device connection request, the access point determines whether or not the authentication method and password included in the received device connection request match the authentication method and password held inside the access point. If they match, the access point wirelessly outputs a connection permission response, and if they do not match, a connection non-permission response is wirelessly output.
After issuing the AP JOIN Mseg, the NW sub CPU 621 determines whether or not the connection with the access point is successful. Specifically, the NW sub CPU 621 determines whether or not the connection permission response is received from the access point. When the NW sub CPU 621 does not receive the connection permission response from the access point and determines that the connection with the access point has failed, the fact that the connection with the access point has failed and the reason why the connection has failed (for example, password mismatch) ) Is notified to the CPU 602. On the other hand, when the NW sub CPU 621 receives the connection permission response from the access point and determines that the connection with the access point is successful, the NW sub CPU 621 notifies the CPU 602 of the AP JOIN completion notification of successful connection.

Note that the NW sub CPU 621 may transmit the device search request command a plurality of times in the AP search using each channel. Further, at this time, CPU 602 does not have to use all the communication channels that can be executed by MFP 300, and at least use the communication channels other than the communication channel used in the disconnected infrastructure connection. The order of the channels used at this time is not particularly limited. For example, the CPU 602 first executes the AP search using the channel currently used for the P2P connection, and then uses the channels in order from the first channel. Then, the AP search may be executed. When using the frequency bands of 2.4 GHz (1 to 13 channels) and 5 GHz (36 to 140 channels), the CPU 602 preferentially uses a channel corresponding to one of the frequency bands (for example, 5 GHz) to perform an AP search. May start.

As described above, when the infrastructure connection is disconnected while the MFP 300 is not in the simultaneous operation mode or when the power of the MFP 300 is turned on, the infrastructure connection reconnection process is executed by the NW sub CPU 621 instead of the CPU 602. .. Further, the NW sub CPU 621 executes the AP search by the same method regardless of the device state and communication state of the MFP 300. In the above case, the P2P connection is not established, and the problems of packet loss and transmission packet delay in the communication in the P2P mode do not occur. Therefore, the infrastructure connection is re-established according to the device state and communication state of the MFP 300. This is because connection processing is not required. Further, the reconnection process in the above case is executed by the NW sub CPU 621 instead of the CPU 602, so that the load on the CPU 602 can be reduced. With such a load balancing system, it is possible to improve the performance of the entire MFP 300 during the reconnection process of the infrastructure connection.

Further, NW sub CPU 621 uses all communication channels that can be executed by MFP 300 in order from the channel with the smallest number, and executes an AP search at a cycle of 500 msec until an access point is detected. As described above, the NW sub CPU 621 executes the reconnection process when the infrastructure connection is disconnected while the MFP 300 is not in the simultaneous operation mode or when the power of the MFP 300 is turned on. However, in such a case, problems such as packet loss and transmission packet delay in communication in the P2P mode do not occur. Therefore, the NW sub CPU 621 can execute an AP search whose search type is ALL in a short cycle.

On the other hand, if the infrastructure connection is disconnected while the MFP 300 is in the simultaneous operation mode, or if the LAN setting change processing is executed while the MFP 300 is in the simultaneous operation mode, the infrastructure connection reconnection processing is performed by the NW. It is executed by the CPU 602 instead of the sub CPU 621. As a result, in a state where the MFP 300 is in the simultaneous operation mode, connection processing is executed according to the device state and communication state of the MFP 300.

<Second Embodiment>
In the above-described embodiment, when the infrastructure connection is disconnected, the CPU that is the main body that executes the reconnection process is switched depending on whether or not the MFP 300 is in the simultaneous operation mode. In the present embodiment, a mode will be described in which the CPU that is the main body that executes the reconnection process is switched in consideration of other factors.

The communication system and the configuration of each device of this embodiment are the same as those of the first embodiment.

FIG. 16 is a flowchart showing the processing executed by the CPU 602 by the I/F connection Mgr 1011. The process shown in this flowchart is realized by the CPU 602 reading a program corresponding to the I/F connection Mgr 1011 stored in a memory such as the ROM 603 into the RAM 604 and executing the program. Further, the processing at the time of power-on is the same as that in the first embodiment, and thus the description thereof will be omitted.

[LAN setting change processing]
The processing of S1630 to S1632 is the same as the processing of S1130 to S1132, and thus the description thereof is omitted.

When the CPU 602 determines in S1631 that the MFP 300 is in the simultaneous operation mode, the CPU 602 determines whether the user is operating the operation display unit 610 (S1633). On the other hand, it is highly possible that the user who has instructed to change the LAN setting is still operating the operation display unit 610. In particular, when the MFP 300 is equipped with a touch panel as the operation display unit 610, the CPU 602 needs to draw GUI parts on the touch panel in accordance with user operations such as touch and drag on the touch panel. Generally, if the drawing of the GUI part is delayed by 100 msec or more with respect to the user operation with respect to the touch, the user feels uncomfortable. Therefore, when the user is operating the operation display unit 610, the CPU 602 must give priority to processing within the UI domain, such as drawing of GUI parts. Therefore, when the CPU 602 determines that the user is operating the operation display unit 610, the CPU 602 proceeds to S1632 and causes the NW sub CPU 621 to execute the reconnection process. As a result, the CPU 602 can focus on processing within the UI domain when the user is operating the operation display unit 610, and executes processing such as drawing of GUI parts without making the user feel uncomfortable. it can. If the CPU 602 determines that the user is not operating the operation display unit 610, the CPU 602 performs the processing from S1643. The processing of S1643 to S1646 is the same as the processing of S1142 to S1145, and thus the description thereof is omitted.

[Infrastructure reconnection processing]
The processing of S1640 and S1641 is the same as the processing of S1140 and S1141, and thus the description thereof is omitted.

When the CPU 602 determines in S1641 that the MFP 300 is in the simultaneous operation mode, the CPU 602 determines whether or not there is a device that is P2P connected to the MFP 300 (S1642). As described above, once the MFP 300 is set to the simultaneous operation mode, even if the P2P connection or the infrastructure connection is disconnected, the simultaneous operation mode is not canceled unless the setting of the communication mode is changed. That is, the MFP 300 may not execute the P2P connection even in the simultaneous operation mode. Even in the simultaneous operation mode, when the P2P connection is not executed, the reconnection process of the infrastructure connection does not affect the communication in the P2P mode, and there are problems such as packet loss and transmission packet delay in the communication in the P2P mode. Does not occur. Therefore, it is not necessary for the CPU 602 to execute the infrastructure connection reconnection processing according to the apparatus state of the MFP 300. Therefore, when the CPU 602 determines that there is no device P2P-connected to the MFP 300, the CPU 602 proceeds to step S1647 and issues a P2P controller STOP command to the NW sub CPU 621 to stop the MFP 300 from operating as a software AP. After that, the CPU 602 causes the NW sub CPU 621 to execute reconnection processing for infrastructure connection. As a result, the reconnection process of the infrastructure connection is executed with the load on the CPU 602 reduced. If the CPU 602 determines that there is no device that is P2P connected to the MFP 300, the CPU 602 performs the processes from S1643. The processing of S1643 to S1646 is the same as the processing of S1142 to S1145, and thus the description thereof is omitted.

<Other embodiments>
The present invention is to dispose a wireless connection sequencer on both the main subsystem side and the NW subsystem side to perform load distribution of the connection sequence according to the situation. The connection sequence to be used may be determined according to the user setting, or may be determined based on the user operation status, the user usage status, or a composite condition thereof.

In the infrastructure reconnection process of the above-described embodiment, the determination of whether the MFP 300 is in the simultaneous operation mode may be performed by determining whether the MFP 300 is in the P2P connection with the terminal device 200. Alternatively, it may be performed by determining whether or not the MFP 300 is operating as a GroupOwner (or software AP). It should be noted that in the above-described embodiment, the MFP 300 can accept the setting of whether or not to execute the negotiation in the wireless connection sequence in the WFD mode from the user, and if the setting for executing the negotiation is made, the simultaneous operation is performed. Do not run. Therefore, at the timing when the connection between the MFP 300 and the access point 400 is disconnected, the MFP 300 does not make the P2P connection with the terminal device 200 operating as the GroupOwner. If the MFP 300 is P2P-connected, the MFP 300 is operating as a GroupOwner (or software AP). Therefore, the CPU 602 can determine whether the MFP 300 is in the P2P connection with the terminal device 200 by determining whether the MFP 300 is operating as the GroupOwner (or software AP). When the MFP 300 is not operating as the GroupOwner (or the software AP), the CPU 602 determines that the MFP 300 is not in the P2P connection. On the other hand, the CPU 602 determines that the MFP 300 is in the P2P connection when the MFP 300 is operating as the GroupOwner (or software AP). If the MFP 300 is not in the P2P connection, only the interface for executing the communication in the infrastructure mode is operating independently. That is, the connection between the MFP 300 and the access point 400 is disconnected while the MFP 300 is not performing the simultaneous operation. Therefore, when determining that the MFP 300 is not in the P2P connection, the CPU 602 causes the NW sub CPU 621 to execute the reconnection process. When determining whether or not the MFP 300 is in the simultaneous operation mode by determining whether or not the MFP 300 is in the P2P connection with the terminal device 200, the determination in S1642 is omitted.

In the above-described embodiment, the MFP 300 uses Wi-Fi to execute the communication in the P2P mode and the communication in the infrastructure mode, but the present invention is not limited to this. For example, another communication method such as Bluetooth may be used.
The embodiment described above is also realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or device via a network or various storage media, and the computer (CPU, MPU, etc.) of the system or device reads the program. This is the process to be executed. Further, the program may be executed by one computer or may be executed by interlocking a plurality of computers. Further, it is not necessary to realize all of the above-mentioned processing by software, and some or all of the processing may be realized by hardware such as ASIC. Further, the CPU is not limited to one in which all the processes are performed, and a plurality of CPUs may perform the processes while cooperating appropriately.

200 Terminal device 300 MFP
400 Access point 602 CPU
621 NW sub CPU

Claims (15)

A communication device,
Of the channels usable by the communication device, a connection is established between the external device and the communication device in a first wireless network using a predetermined channel, and the terminal device and the communication device are used in the predetermined channel. Connection means for establishing a connection in the second wireless network of
A first control unit that acquires a communication state between the terminal device and the communication device and performs control based on the communication state;
A second control means different from the first control means,
Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel When the connection between the external device and the communication device using the predetermined channel is disconnected in a state in which the first control device and the communication device are established in parallel, the first control unit executes the first control unit. Searching the external device by a search method specified according to the communication state between the terminal device and the communication device among a plurality of possible search methods,
A connection in the first wireless network is established between the external device and the communication device using the predetermined channel, and the second device is connected to the terminal device and the communication device using the predetermined channel. When the connection between the external device and the communication device using the predetermined channel is disconnected in a state where the connection in the wireless network is not established, the second control unit causes the second control unit to communicate with the terminal device and the communication device. A communication device for searching the external device by a predetermined method regardless of a communication state with the communication device. The communication device according to claim 1, wherein the first control unit has a processing speed higher than that of the second control unit. Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel Are established in parallel, the connection between the external device and the communication device using the predetermined channel is disconnected by changing the setting of the connection information for connecting to the external device. In this case, the first control means searches the external device using the predetermined channel among the plurality of search methods, and does not search the external device using at least a channel other than the predetermined channel. The communication device according to claim 1 or 2, wherein the external device is searched by a search method. Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel Are established in parallel, when the connection between the external device and the communication device using the predetermined channel is disconnected, the first control means, among the plurality of search methods, In a state where communication between the terminal device and the communication device is not being executed, a search for the external device is repeated a predetermined number of times using the predetermined channel, and a search for the external device using the predetermined channel is performed. The external device is searched by a search method for searching the external device by using at least a channel other than the predetermined channel when the external device is not detected. The communication device according to the item. Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel Are established in parallel, when the connection between the external device and the communication device using the predetermined channel is disconnected, the first control means, among the plurality of search methods, In a state where communication between the terminal device and the communication device is not being executed, the search for the external device is repeated a predetermined number of times in the first cycle using the predetermined channel, and the predetermined channel is used. If the external device is not detected by repeating the search for the external device for the predetermined number of times in the first period, at least a channel other than the predetermined channel is used, and The communication device according to claim 4, wherein the external device is searched by a search method in which the search for the external device is repeated in a long second cycle. Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel Are established in parallel, and the communication between the external device and the communication device is being executed, the connection between the external device and the communication device using the predetermined channel is disconnected. In this case, the first control means repeats the search for the external device a predetermined number of times using the predetermined channel among the plurality of search methods, and uses the predetermined channel for the predetermined number of times, When the external device is not detected by repeating the search for the external device, the external device is searched by a search method for searching the external device using at least a channel other than the predetermined channel. The communication device according to claim 1. Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel Are established in parallel, and the communication between the external device and the communication device is being executed, the connection between the external device and the communication device using the predetermined channel is disconnected. In this case, the first control means repeats the search for the external device a predetermined number of times in a third cycle shorter than the first cycle using the predetermined channel among the plurality of search methods. If the external device is not detected by repeating the search for the external device for the predetermined number of times in the third cycle using the predetermined channel, at least a channel other than the predetermined channel is used. 7. The external device is searched by a search method in which the search for the external device is repeated in a fourth cycle that is shorter than the second cycle and longer than the third cycle. Communication device. Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel Are established in parallel, when the connection between the external device and the communication device using the predetermined channel is disconnected, the first control means, among the plurality of search methods, In the state where the communication between the terminal device and the communication device is being performed, the search for the external device is repeated using the predetermined channel until the communication between the terminal device and the communication device is completed, Until the communication between the terminal device and the communication device is completed, if the external device is not detected by searching the external device using the predetermined channel, at least a channel other than the predetermined channel is used. The communication device according to any one of claims 1 to 7, wherein the external device is searched by a search method for searching for the external device. Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel Are established in parallel, when the connection between the external device and the communication device using the predetermined channel is disconnected, the first control means, among the plurality of search methods, In the state where the communication between the terminal device and the communication device is being performed, the search for the external device is repeated using the predetermined channel until the communication between the terminal device and the communication device is completed, Until the communication between the terminal device and the communication device is completed, if the external device is not detected by searching the external device using the predetermined channel, at least a channel other than the predetermined channel is used. Then, the external device is not detected by repeating the search for the external device in the fifth cycle and repeating the search for the external device in the fifth cycle using at least a channel other than the predetermined channel. 9. The communication device according to claim 8, wherein, in the case of the above, the external device is searched by a search method in which the search of the external device is repeated in a sixth cycle that is longer than the fifth cycle. Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel Are established in parallel, the communication device is turned off, and the connection between the external device and the communication device using the predetermined channel is cut off. The second control means searches for the external device by the predetermined method regardless of the communication state between the terminal device and the communication device when the power of the device is turned on. The communication device according to any one of claims 1 to 9. The communication device according to any one of claims 1 to 10, wherein the predetermined method is a search method for searching the external device using all channels available to the communication device. .. The first control unit and the second control unit sequentially use all channels available to the communication device when searching for the external device using all channels available to the communication device. The communication device according to claim 1, wherein the communication device searches for the external device. The communication device according to any one of claims 1 to 12, wherein the predetermined channel used for connecting the external device and the communication device is determined by the external device. The communication device according to any one of claims 1 to 13, wherein a connection with the terminal device in the first wireless network is formed by Wi-Fi Direct (registered trademark). A method for controlling a communication device, comprising: first control means for acquiring a communication state with a terminal device and performing control based on the communication state; and second control means different from the first control means. hand,
Of the channels usable by the communication device, a connection is established between the external device and the communication device in a first wireless network using a predetermined channel, and the terminal device and the communication device are used in the predetermined channel. A connection step for establishing a connection in the second wireless network of
Connection of the external device and the communication device in the first wireless network using the predetermined channel, and connection of the terminal device and the communication device in the second wireless network using the predetermined channel When the connection between the external device and the communication device using the predetermined channel is disconnected in a state in which the first control unit is established in parallel, the first control unit executes the first control unit. Among the plurality of possible search methods, the external device is searched by the search method specified according to the communication state between the terminal device and the communication device, and the external device and the communication device using the predetermined channel The connection in the first wireless network is established and the connection between the terminal device and the communication device using the predetermined channel in the second wireless network is not established. When the connection between the external device and the communication device using a channel is cut off, the second control means is caused to control the external device by a predetermined method regardless of the communication state between the terminal device and the communication device. A control method comprising: a search step for searching.

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