JP5979521B1 - Slave unit, monitor and communication method - Google Patents

Abstract

Even if a predetermined event such as operation of a call button in a plurality of devices is performed almost simultaneously, a synchronization request collision is prevented from occurring continuously in a doorphone master unit. A door phone master unit transmits a unique identifier and a transmission cycle uniquely determined by the identifier to the entrance slave unit 100-1 and the entrance slave unit 100-3. The entrance slave device 100-1 and the entrance slave device 100-3 store these pieces of information received from the doorphone master device. In the asynchronous state, when the call buttons of the entrance slave device 100-1 and the entrance slave device 100-3 are operated almost simultaneously, the entrance slave device 100-1 and the transmission entrance slave device 100-3 have different transmission periods (1 ms). 3 ms), the synchronization request is transmitted a plurality of times. [Selection] Figure 19

Description

The present disclosure handset of the intercom system, a communication method of monitor and the doorphone system.

  In recent years, in homes and the like, for example, a slave unit with a camera installed at a front door outside the home (hereinafter referred to as “entrance slave unit”) and a video image captured by the camera of the entrance slave unit are displayed on a monitor. A door phone system comprising a main phone (hereinafter referred to as “door phone master”) is widely used. In some cases, a monitor is added to the door phone system (hereinafter referred to as “additional monitor”).

  Generally, in a door phone system, an entrance cordless handset and a door phone master phone are connected by a two-wire cable. Further, the door phone master unit and the extension monitor are connected by a two-wire cable. Patent Document 1 describes a door phone system that transmits and receives packets between an entrance cordless handset and a doorphone master set connected by a two-wire cable.

  When the call button of the entrance unit is operated, the entrance unit transmits a synchronization request (control signal) to the doorphone master unit.

JP 2007-124227 A

  When the call buttons of multiple entrance slave units are operated almost simultaneously while each device is in an asynchronous state, multiple synchronization requests will be sent to the doorphone master unit at the same time. Occurs and no synchronization request can be received.

  When the doorphone master unit cannot receive the synchronization request, each entrance slave unit retransmits the synchronization request at a predetermined cycle. In the prior art, since the transmission frequency of the synchronization request of each entrance cordless handset is the same, there is a possibility that the synchronization request will continue to be collided thereafter, and the communication state cannot be changed.

The purpose of the present disclosure is to communicate in a short time without causing continuous synchronization request collisions even when a predetermined event such as operation of a call button is performed almost simultaneously in a plurality of devices in an asynchronous state. handset of the intercom system can transition to a state is to provide a communication method of monitor and the doorphone system.

  The child device of the present disclosure includes the child device of the door phone system in which a parent device and a child device are connected via a two-wire cable, and packet signals are transmitted and received between the parent device and the child device by time division duplex. A receiving unit that receives data from the base unit, a storage unit that stores an identifier that is assigned by the base unit and is included in the received data, and a transmission unit that transmits data to the base unit The transmission unit transmits a synchronization request to the parent device a plurality of times at a transmission cycle uniquely determined by the identifier in an asynchronous state with the parent device.

The monitor according to the present disclosure is a monitor added to a door phone system including a parent device and a child device, and is assigned by the parent device included in the reception data and a reception unit that receives data from the parent device. A storage unit that stores the received identifier and a transmission unit that transmits data to the parent device, and the transmission unit sends a synchronization request to the parent device in an asynchronous state with the parent device. Transmit multiple times with a transmission cycle uniquely determined by

In the communication method of the present disclosure, a communication between a master phone and another device is connected via a two-wire cable, and a communication of a door phone system that transmits and receives packet signals by time division duplex between the master device and the other device. The master device transmits data including an identifier unique to the other device and a transmission cycle uniquely determined by the identifier, and the other device is in an asynchronous state with the master device. transmitting a plurality of times a synchronization request to the parent device in front Kioku Shin cycle.

  According to the present disclosure, when a predetermined event such as an operation of a call button is performed almost simultaneously in a plurality of devices in an asynchronous state, each device transmits a synchronization request multiple times with different transmission cycles. Therefore, it is possible to shift to the communication state in a short time without continuous synchronization request collisions.

The system block diagram which shows the structure of the door phone system which concerns on one embodiment of this indication The figure which shows the frame structure and slot structure which concern on one embodiment of this indication The figure which shows the structure of the interrupt signal which concerns on one embodiment of this indication The block diagram which shows the structure of the entrance cordless handset which concerns on one embodiment of this indication The block diagram which shows the structure of the door phone main unit which concerns on one embodiment of this indication The block diagram which shows the structure of the expansion monitor which concerns on one embodiment of this indication The figure which shows an example of the modulation process with respect to packet data (1 bit) The figure which shows an example of the modulation process with respect to packet data (multiple bits) The figure which shows an example of the preamble data used in one embodiment of this indication The block diagram which shows the internal structure of the synchronous detection part of the entrance cordless handset which concerns on one embodiment of this indication The figure which shows an example of the synchronous detection process of the entrance cordless handset which concerns on one embodiment of this indication The flowchart which shows an example of operation | movement of the synchronous detection process which concerns on one embodiment of this indication Sequence diagram until initial registration according to an embodiment of the present disclosure Sequence diagram from standby state to communication state according to an embodiment of the present disclosure The flowchart which shows an example of operation of the entrance cordless handset concerning an embodiment of this indication The flowchart which shows an example of operation of the door phone main unit concerning an embodiment of this indication The figure which shows the specific example of the routing control at the time of normal operation | movement of the door phone main unit which concerns on one embodiment of this indication The figure which shows the specific example of the routing control at the time of the initial registration of the door phone main unit which concerns on one embodiment of this indication The figure which shows an example of the table in the identifier memory | storage part of the door phone main unit which concerns on one embodiment of this indication The figure explaining the collision avoidance in the asynchronous state of the door phone system concerning one embodiment of this indication

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

<System overview>
First, the outline | summary of the door phone system which concerns on one embodiment of this indication is demonstrated using FIG. As shown in FIG. 1, the door phone system 1 includes an entrance cordless handset 100 and a door phone master set 200. Note that FIG. 1 illustrates a case where three door slave devices 100-1, 100-2, and 100-3 are connected to the doorphone master device 200. Further, an additional monitor 300 may be added to the door phone system 1. Furthermore, the door phone system 1 can be connected to other door phone systems.

  The entrance cordless handset 100 is provided, for example, at the entrance of a house or the like. The intercom master device 200 and the extension monitor 300 are provided in a home such as a house, for example, and are fixed to a wall or placed on a table or a table. The entrance cordless handset 100 and the door phone master set 200 are connected by a two-wire cable made of a pair of copper wires. The extension monitor 300 is connected to the door phone master unit 200 by a two-wire cable.

  The intercom master device 200 communicates with the entrance slave device 100, receives video data, audio data, and control data from the entrance slave device 100, and transmits the audio data and control data. The intercom base unit 200 communicates with the expansion monitor 300, transfers the video data, audio data, and control data received from the front door unit 100 to the expansion monitor 300, and receives the audio data and control data received from the expansion monitor 300. Is transferred to the entrance cordless handset 100.

  In the following description, the direction from the entrance slave unit 100 or the extension monitor 300 to the doorphone master unit 200 is referred to as “upward direction”, and packets and signals transmitted from the entrance slave unit 100 or the extension monitor 300 in the upward direction are referred to as “upward direction”. They are called “upstream packet” and “upstream signal”, respectively. Further, the direction from the doorphone master unit 200 to the entrance slave unit 100 or the extension monitor 300 is referred to as “downward direction”, and packets and signals transmitted from the doorphone master unit 200 in the downward direction are referred to as “downstream packet” and “downstream signal”, respectively. "

<Frame configuration, slot configuration>
Next, a frame configuration and a slot configuration during synchronous communication according to the present embodiment will be described with reference to FIG. 2A. As shown in FIG. 2A, each frame has a 48000 bit area, has a 10 ms period, a 4.8 Mbps bit rate, and is divided into 24 slots. Therefore, each slot has an area of 2000 bits = 250 bytes, and has a bit rate of 0.416 ms and a bit rate of 4.8 Mbps.

  Each slot is divided into a 52-byte guard space (Guard), a 4-byte preamble field, a 2-byte sync field (Sync), a 32-byte control data field, and a 160-byte user data field.

  The guard space is a time for avoiding a slot collision due to a propagation delay time difference, clock jitter, or the like. Preamble data (described later) having a predetermined unique pattern is added to the preamble field. A predetermined sync pattern is added to the sync field. Control data is added to the control data field. Image data and audio data are added to the user data field. Here, the sync pattern is known data or a data string arranged in the sync field, and is used to establish synchronization at the time of reception data reception, and confirms that reception data has been received at an accurate timing. This is a known data pattern defined in advance.

<Configuration of interrupt signal>
Next, the configuration of an interrupt signal during asynchronous communication according to the present embodiment will be described with reference to FIG. 2B.

  As shown in FIG. 2B, the interrupt signal is divided into a 4-byte preamble field, a 2-byte sync field (Sync), and a 32-byte control data field. Further, the interrupt signal shown in FIG. 2B is provided with a 30-byte user data field for future expansion.

  The preamble data and the sync pattern of the interrupt signal are the same as the slots in the synchronous communication shown in FIG. 2A. Thereby, since a receiving part etc. can be shared by the time of synchronous communication and the time of asynchronous communication, cost can be held down.

  In the control data field of the interrupt signal, control information such as a message type (synchronization request or the like) and a transmission source device number (ID) is written. The user data field of the interrupt signal may be used as a field for notifying detailed information corresponding to the message type, such as device abnormality information (information indicating that a device abnormality is detected).

  Note that the interrupt signal shown in FIG. 2B is also used during initial registration of the connected device.

<Configuration of entrance cordless handset>
Next, the structure of the entrance cordless handset 100 is demonstrated using the block diagram of FIG. As shown in FIG. 3, the entrance slave device 100 includes a cable connection unit 101, a key input unit 102, a speaker 103, a microphone 104, an audio I / F (interface) unit 105, a camera unit 106, and a control unit 107. The control unit 107 includes a first clock generation unit 131, a packet generation unit 132, a data reproduction unit 133, and a connection state detection unit 134 inside. Further, the entrance slave device 100 includes a transmission data processing unit 108, a transmission data inversion unit 109, a transmission driver 110, a reception driver 111, a reception data inversion unit 112, a synchronization detection unit 113, a second clock generation unit 114, and an identifier storage unit 115. Have

  The cable connection unit 101 includes a connection terminal for a two-wire cable, and connects the one end on the entrance side of the two-wire cable to the reception driver 111 and the transmission driver 110 in a state where signals can be transmitted. Note that the other end of the two-wire cable is connected to the doorphone master unit 200.

  The key input unit 102 includes a call button. When the call button is operated, the key input unit 102 outputs a signal indicating that to the control unit 107.

  The speaker 103 converts the analog audio data output from the audio I / F unit 105 into audio and outputs the audio.

  The microphone 104 collects ambient sound, converts it into analog sound data, and outputs it to the sound I / F unit 105.

  The audio I / F unit 105 converts the digital audio data output from the control unit 107 into analog audio data, adjusts the signal level, and outputs the analog audio data to the speaker 103. The audio I / F unit 105 adjusts the signal level of the analog audio data output from the microphone 104, converts the analog audio data into digital audio data, and outputs the digital audio data to the control unit 107. Such analog / digital conversion is performed by an A / D, D / A converter (not shown).

  The audio I / F unit 105 outputs data obtained by performing predetermined audio compression processing on the data obtained by digitally converting the analog audio data output from the microphone 104 to the control unit 107 as digital audio data. May be. In addition, when the digital audio data output from the control unit 107 is data obtained by performing predetermined audio compression processing, the audio I / F unit 105 performs predetermined audio expansion processing on the data. To digital / analog conversion.

  The camera unit 106 includes a digital camera, takes a video of the entrance, generates digital video data, and outputs the digital video data to the control unit 107. Note that the camera unit 106 may include an encoder module. That is, the camera unit 106 may output data obtained by performing predetermined moving image compression processing such as H.264 to the video data output from the digital camera to the control unit 107 as digital video data.

  The control unit 107 controls each part of the entrance cordless handset 100. In addition, the control unit 107 outputs a transmission control signal (SW CON) that indicates a transmission period that permits transmission and a reception period that permits reception to the transmission driver 110 and the reception driver 111.

  The first clock generation unit 131 of the control unit 107 is a clock for sampling the reception data, and the first frequency corresponding to n times (n is 1 or more) the bit rate of the reception data on the basis of the crystal oscillation. A clock (CLK) of (eg, 48 MHz (n = 10)) is generated and output to the synchronization detection unit 113 and the second clock generation unit 114.

The packet generation unit 132 of the control unit 107 generates an uplink packet for realizing a call with video. Specifically, the packet generation unit 132 divides the digital audio data output from the audio I / F unit 105 and the digital video data output from the camera unit 106 as appropriate and writes them to the user data field of each slot. Control data including an identifier (hereinafter referred to as “own device ID _slave ”) unique to the device (the entrance _slave device 100) and an identifier of the communication partner doorphone parent device 200 (hereinafter referred to as “ID _master ”) is controlled in each slot. Write to the data field. Furthermore, the packet generation unit 132 writes preamble data and a sync pattern in each slot, and generates an uplink packet (transmission data). Further, the packet generation unit 132 generates a transmission enable signal (SSCS) and a transmission second frequency (for example, 4.8 MHz) clock (SSCK). Then, the packet generation unit 132 outputs the uplink packet to the transmission data processing unit 108 in synchronization with the transmission enable signal (SSCS) and the clock (SSCK).

  Note that, in a standby state in which data is not transmitted and received between the front door device 100 and the door phone master device 200, the packet generation unit 132 does not generate an upstream packet. In a standby state (during asynchronous communication), when a predetermined event such as an operation of a call button occurs, the packet generation unit 132 transmits an upstream packet (interrupt signal) in which preamble data, sync pattern, and control data are written. Generate. The preamble and sync pattern used in the interrupt signal during asynchronous communication are the same as those used during synchronous communication.

When the data reproduction unit 133 of the control unit 107 receives the enable signal (SSCS) from the synchronization detection unit 113, the data reproduction unit 133 uses the second frequency clock (SSCK) output from the second clock generation unit 114, and receives the data inversion unit. The downlink signal output from 112 is demodulated to obtain a downlink packet. Then, the data reproduction unit 133 outputs the digital audio data included in the downlink packet to the audio I / F unit 105, and outputs the sync pattern included in the downlink packet (received data) to the connection state detection unit 134. Note that the data reproduction unit 133 causes the identifier storage unit 115 to store its own device ID _slave and ID _master included in the downlink packet at the time of initial registration.

  Further, when a predetermined event occurs in a standby state (during asynchronous communication) and a downlink signal (interrupt signal) is input, the data reproduction unit 133 demodulates the downlink signal to acquire a downlink packet, and is included in the downlink packet The sync pattern is output to the connection state detection unit 134. The data reproduction unit 133 extracts control data of the interrupt signal after confirming that the connection state detection unit 134 has correctly captured the interrupt signal. If the control data is a synchronization request, the entrance slave device 100 shifts to a synchronization process with the doorphone master device 200.

  The connection state detection unit 134 of the control unit 107 is a check sync pattern (hereinafter, referred to as a “positive connection check sync pattern” (for example, all 16 bits are “0”)) when the two-wire cable is connected correctly. This is a reverse pattern of the normal connection check sync pattern, and the check sync pattern when the two-wire cable is reverse connected (hereinafter referred to as “reverse connection check sync pattern” (eg, all 16 bits are “1”). )) Is remembered. Then, the connection state detection unit 134 collates the sync pattern of the reception data output from the data reproduction unit 133 with the sync pattern for the normal connection check and the sync pattern for the reverse connection check. The connection state detection unit 134 determines that the two-wire cable is correctly connected when the sync pattern of the received data completely matches the sync pattern for the normal connection check, and the sync pattern of the received data and the sync pattern for the reverse connection check If the two completely match, it is determined that the two-wire cable is reversely connected. Then, the connection state detection unit 134 outputs an inversion control signal (INV CON) indicating the determination result to the transmission data inversion unit 109 and the reception data inversion unit 112.

  When the transmission data processing unit 108 receives the enable signal (SSCS) from the packet generation unit 132, the transmission data processing unit 108 uses the second frequency clock (SSCK) output from the packet generation unit 132, and the uplink data output from the packet generation unit 132. Modulation processing is performed on the packet data to generate an uplink signal, which is output to the transmission data inverting unit 109. Details (specific example) of the modulation processing of the transmission data processing unit 108 will be described later.

  When the connection state detection unit 134 determines that the two-wire cable is reversely connected, the transmission data inversion unit 109 inverts the uplink signal output from the transmission data processing unit 108 and outputs the inverted signal to the transmission driver 110. On the other hand, when the connection state detection unit 134 determines that the two-wire cable is a normal connection, the transmission data reversing unit 109 outputs the uplink signal output from the transmission data processing unit 108 to the transmission driver 110 as it is.

  The transmission driver 110 transmits an uplink signal to the intercom base unit 200 via the cable connection unit 101 in the transmission section instructed by the switching control signal (SW CON) from the control unit 107.

  The reception driver 111 receives the downlink signal transmitted from the doorphone master device 200 via the cable connection unit 101. Then, the reception driver 111 outputs a downlink signal to the reception data inversion unit 112 in the reception period instructed by the switching control signal (SW CON) from the control unit 107.

  When the connection state detection unit 134 determines that the two-wire cable is reversely connected, the reception data inversion unit 112 inverts the downlink signal output from the reception driver 111 to synchronize the detection unit 113 and the second clock generation unit. 114 and output to the data reproduction unit 133. On the other hand, when the connection state detection unit 134 determines that the two-wire cable is a positive connection, the reception data inversion unit 112 directly uses the downlink signal output from the reception driver 111 as the synchronization detection unit 113 and the second clock generation unit. 114 and output to the data reproduction unit 133.

  The synchronization detection unit 113 uses the first frequency clock (CLK) output from the first clock generation unit 131 and uses the preamble data included in the downlink signal output from the reception driver 111 to Synchronization (start timing of each bit of received data) is detected. Then, the synchronization detection unit 113 outputs a trigger signal serving as a reference for starting clock output to the second clock generation unit 114 at the timing when the unique pattern of the preamble data is detected, and an enable signal (SSCS) that permits the data reproduction operation Is output to the data reproducing unit 133. The details of the configuration of the synchronization detection unit 113 will be described later.

  The second clock generation unit 114 corresponds to the bit rate of the received data with reference to the first frequency clock (CLK) output from the first clock generation unit 131 at the timing instructed by the synchronization detection unit 113. A clock (SSCK) having two frequencies (for example, 4.8 MHz) is generated and output to the data reproducing unit 133.

The identifier storage unit 115 stores the own device ID _slave and the ID _master received from the intercom master device 200.

<Configuration of doorphone master unit>
Next, the configuration of door phone master device 200 will be described using the block diagram of FIG. As shown in FIG. 4, door phone master device 200 includes a cable connection unit 201, a key input unit 202, a speaker 203, a microphone 204, an audio I / F unit 205, a display unit 206, and a control unit 207. The control unit 207 includes a first clock generation unit 231, a packet generation unit 232, a data reproduction unit 233, a connection state detection unit 234, and an identifier setting unit 235 inside. The intercom 200 has a transmission data processing unit 208, a transmission data inversion unit 209, a transmission driver 210, a reception driver 211, a routing control unit 212, a synchronization detection unit 213, a second clock generation unit 214, and an identifier storage unit 215. Have. The doorphone parent device 200 has N (N is a natural number) the cable connection unit 201, the transmission driver 210, and the reception driver 211.

  The cable connection portion 201-i (i is any integer from 1 to N) includes a connection terminal for a two-wire cable, one end on the indoor side of the two-wire cable, a transmission driver 210-i, and a reception driver 211. -I is connected in a state where signals can be transmitted. In addition, the other end of each two-wire cable is connected to the main unit of the entrance cordless handset 100, the extension monitor 300, or another door phone system. In FIG. 4, the case where the cable connection part 201-1 is connected to the main | base station of another door phone system is illustrated.

  The key input unit 202 includes a response button. When the response button is operated, the key input unit 202 outputs a signal indicating that to the control unit 207.

  The speaker 203 converts the analog audio data output from the audio I / F unit 205 into audio and outputs the audio.

  The microphone 204 collects surrounding sounds, converts them into analog sound data, and outputs the analog sound data to the sound I / F unit 205.

  The audio I / F unit 205 converts the digital audio data output from the control unit 207 into analog audio data, adjusts the signal level, and outputs the analog audio data to the speaker 203. The audio I / F unit 205 adjusts the signal level of the analog audio data output from the microphone 204, converts the analog audio data into digital audio data, and outputs the digital audio data to the control unit 207. Such analog / digital conversion is performed by an A / D, D / A converter (not shown).

  The audio I / F unit 205 outputs data obtained by performing predetermined audio compression processing on the data obtained by digitally converting the analog audio data output from the microphone 204 to the control unit 207 as digital audio data. May be. In addition, when the digital audio data output from the control unit 207 is data obtained by performing predetermined audio compression processing, the audio I / F unit 205 performs predetermined audio expansion processing on the data. To digital / analog conversion.

  The display unit 206 includes a liquid crystal display, reproduces digital video data output from the control unit 207, and displays an entrance video. When the digital video data output from the control unit 207 is data obtained by performing a predetermined moving image compression process, a predetermined moving image expansion process is performed on the data to display a video.

  The control unit 207 controls each unit of the door phone master device 200. In addition, the control unit 207 sends a transmission control section (SW CON) that indicates a transmission section that permits transmission and a reception section that permits reception to each transmission driver 210-i, each reception driver 211-i, and a routing control section. It outputs to 212.

  The first clock generation unit 231 of the control unit 207 is a clock for sampling received data, and is based on crystal oscillation and has a first frequency corresponding to n times the bit rate of the received data (for example, 48 MHz (n = 10)) clock (CLK) is generated and output to the synchronization detector 213 and the second clock generator 214.

The packet generation unit 232 of the control unit 207 generates a downlink packet for realizing a call with video. Specifically, the packet generation unit 232 appropriately divides the digital audio data output from the audio I / F unit 205 and writes it in the user data field of each slot, and an identifier unique to the own device (doorphone master device 200). (Hereinafter referred to as “own device ID _master ”) and the control data including the identifier of the communication partner device are written in the control data field of each slot. Further, the packet generation unit 232 writes the preamble data and the sync pattern in each slot, and generates a downlink packet (transmission data). Furthermore, the packet generation unit 232 generates a transmission enable signal (SSCS) and a transmission second frequency (for example, 4.8 MHz) clock (SSCK). Then, the packet generation unit 232 outputs the downlink packet to the transmission data processing unit 208 in synchronization with the transmission enable signal (SSCS) and the clock (SSCK).

  In addition, the packet generation unit 232 may output control data related to the operation of the doorphone master device 200 or the operation of the front door device 100 to the transmission data processing unit 208 as data to be transmitted to the front door device 100. . Such control data includes, for example, the camera operation (data rate, pan, tilt, light, shutter, filter, etc.) of the doorphone master unit 200 to the entrance slave unit 100 and various sensors provided in the entrance slave unit 100. A control signal for controlling the operation of the device from door phone parent device 200 is included. The control data includes a control signal for controlling the operation of a device (such as a gate electronic key) arranged outdoors via a wireless communication circuit or the like (not shown) provided in the entrance cordless handset 100. Is included.

  The packet generation unit 232 generates a downlink signal including a unique identifier assigned to the registration target device set by the identifier setting unit 235 at the time of initial registration of the devices such as the entrance slave device 100 and the extension monitor 300. .

  Note that, in a standby state in which data is not exchanged between the front door device 100 (or the extension monitor 300) and the intercom master device 200, the packet generation unit 232 does not generate a downlink packet. Further, when a predetermined event such as a response button being operated occurs in a standby state (during asynchronous communication), the packet generation unit 232 transmits a downstream packet (interrupt signal) in which preamble data, sync pattern, and control data are written. Generate. The preamble and sync pattern used in the interrupt signal during asynchronous communication are the same as those used during synchronous communication.

  When the data reproduction unit 233 of the control unit 207 receives the enable signal (SSCS) from the synchronization detection unit 213, the data reproduction unit 233 uses the second frequency clock (SSCK) output from the second clock generation unit 214, and the routing control unit 212. The upstream signal output from is demodulated to obtain the upstream packet. Then, the data reproducing unit 233 outputs the digital audio data included in the upstream packet to the audio I / F unit 205, outputs the digital video data included in the upstream packet to the display unit 206, and the sync pattern included in the upstream packet. Is output to the connection state detection unit 234.

  Further, when a predetermined event occurs in a standby state (during asynchronous communication) and an upstream signal (interrupt signal) is input, the data reproduction unit 233 demodulates the upstream signal to acquire an upstream packet, and is included in the upstream packet The sync pattern to be output is output to the connection state detection unit 234. The data reproduction unit 233 extracts the control data of the interrupt signal after confirming that the connection state detection unit 234 can accurately capture the interrupt signal. If the control data is a synchronization request, the intercom master device 200 shifts to a synchronization process with the entrance slave device 100 or the extension monitor 300.

  The connection state detection unit 234 of the control unit 207 stores the normal connection check sync pattern and the reverse connection check sync pattern, and converts the received data sync pattern output from the data reproduction unit 233 into the normal connection check sync pattern and Match with reverse connection check sync pattern. The connection state detection unit 234 determines that the two-wire cable is correctly connected when the received data sync pattern and the normal connection check sync pattern completely match, and the received data sync pattern and the reverse connection check sync pattern are determined. If the two completely match, it is determined that the two-wire cable is reversely connected. Then, the connection state detection unit 234 outputs an inversion control signal (INV CON) indicating the determination result to the transmission data inversion unit 209.

  The identifier setting unit 235 of the control unit 207 sets a unique identifier to be assigned to each registration target device at the time of initial registration of the devices such as the entrance slave device 100 and the extension monitor 300, and outputs the identifier to the packet generation unit 232. Recording is performed in the recording unit 215. Further, the identifier setting unit 235 reads the identifier recorded in the identifier recording unit 215 as necessary. Note that the identifier setting unit 235 returns the set identifier to the packet generation unit again when the receipt of the identifier is not input from the data reproducing unit 233 even after a predetermined time has elapsed since the identifier was transmitted. Output to H.232.

  When the transmission data processing unit 208 receives the enable signal (SSCS) from the packet generation unit 232, the transmission data processing unit 208 uses the second frequency clock (SSCK) output from the packet generation unit 232, and the downlink data output from the packet generation unit 232. Modulation processing is performed on the packet data to generate a downlink signal, which is output to the routing control unit 212.

  When the connection state detection unit 234 determines that the two-wire cable is reversely connected, the transmission data inverting unit 209 inverts the downlink signal output from the routing control unit 212 and outputs the inverted signal to the transmission driver 210-1. On the other hand, when the connection state detection unit 234 determines that the two-wire cable is a normal connection, the transmission data inversion unit 209 outputs the downlink signal output from the routing control unit 212 to the transmission driver 210-1 as it is.

  The transmission driver 210-1 transmits a downlink signal to the master unit of another door phone system via the cable connection unit 201-1 in the transmission section instructed by the switching control signal (SW CON) from the control unit 207. . The transmission driver 210-i (in this case, i is other than 1) transmits the downstream signal to the entrance via the cable connection unit 201-i in the transmission section instructed by the switching control signal (SW CON) from the control unit 207. It transmits to the subunit | mobile_unit 100 or the expansion monitor 300. FIG.

  The reception driver 211-i receives an upstream signal transmitted from the front cordless handset 100, the extension monitor 300, or the parent device of another door phone system via the cable connection unit 201-i. Then, the reception driver 211-i outputs an uplink signal to the routing control unit 212 in the reception period instructed by the switching control signal (SW CON) from the control unit 207.

  The routing control unit 212 transmits the uplink signal transmitted from the front door slave unit 100 and output from the reception driver 211-i to the master unit 200. When the destination signal is addressed to the master unit 200, the synchronization detection unit 213, the second clock generation unit 214, the data reproduction If it is addressed to the expansion monitor 300, it is output to the corresponding transmission driver 210-i. In addition, the routing control unit 212 outputs the downlink signal output from the transmission data processing unit 208 and addressed to the entrance slave device 100 to the corresponding transmission driver 210-i. In addition, the routing control unit 212 outputs the uplink signal addressed to the entrance slave device 100 transmitted from the extension monitor 300 and output from the reception driver 211-i to the corresponding transmission driver 210-i. The routing control unit 212 controls routing (valid / invalid of communication routes). A specific example of routing control performed by the routing control unit 212 will be described later.

  The synchronization detection unit 213 uses the first frequency clock (CLK) output from the first clock generation unit 231 and uses the preamble data included in the uplink signal output from the routing control unit 212, to the entrance terminal 100. (The timing at the beginning of each bit of received data) is detected. Then, the synchronization detection unit 213 outputs a trigger signal serving as a reference for starting clock output to the second clock generation unit 214 at the timing when the unique pattern of the preamble data is detected, and an enable signal (SSCS) that permits the data reproduction operation Is output to the data reproducing unit 233.

  The second clock generation unit 214 corresponds to the bit rate of the received data based on the first frequency clock (CLK) output from the first clock generation unit 231 at the timing instructed by the synchronization detection unit 213. A clock (SSCK) having two frequencies (for example, 4.8 MHz) is generated, and a clock having the second frequency is output to the data reproducing unit 233.

The identifier storage unit 215 stores the own device ID _master and the identifiers of each device (the entrance slave device 100, the extension monitor 300, and the parent device of another door phone system).

<Configuration of additional monitor>
Next, the configuration of the extension monitor 300 will be described with reference to the block diagram of FIG. As illustrated in FIG. 5, the extension monitor 300 includes a cable connection unit 301, a key input unit 302, a speaker 303, a microphone 304, an audio I / F (interface) unit 305, a display unit 306, and a control unit 307. The control unit 307 includes a first clock generation unit 331, a packet generation unit 332, a data reproduction unit 333, and a connection state detection unit 334 inside. The expansion monitor 300 includes a transmission data processing unit 308, a transmission data inversion unit 309, a transmission driver 310, a reception driver 311, a reception data inversion unit 312, a synchronization detection unit 313, a second clock generation unit 314, and an identifier storage unit 315. Have.

  The cable connection unit 301 includes a connection terminal for a two-wire cable, and connects the one end on the additional monitor side of the two-wire cable to the reception driver 311 and the transmission driver 310 in a state where signals can be transmitted. Note that the other end of the two-wire cable is connected to the doorphone master unit 200.

  The key input unit 302 includes a call button. When the call button is operated, the key input unit 302 outputs a signal indicating that to the control unit 307.

  The speaker 303 converts analog audio data output from the audio I / F unit 305 into audio and outputs the audio.

  The microphone 304 collects ambient sound, converts it into analog sound data, and outputs it to the sound I / F unit 305.

  The audio I / F unit 305 converts the digital audio data output from the control unit 307 into analog audio data, adjusts the signal level, and outputs the analog audio data to the speaker 303. The audio I / F unit 305 adjusts the signal level of the analog audio data output from the microphone 304, converts the analog audio data into digital audio data, and outputs the digital audio data to the control unit 307. Such analog / digital conversion is performed by an A / D, D / A converter (not shown).

  Note that the audio I / F unit 305 outputs data obtained by performing predetermined audio compression processing on the data obtained by digitally converting the analog audio data output from the microphone 304 to the control unit 307 as digital audio data. May be. In addition, when the digital audio data output from the control unit 307 is data obtained by performing predetermined audio compression processing, the audio I / F unit 305 performs predetermined audio expansion processing on the data. To digital / analog conversion.

  The display unit 306 includes a liquid crystal display, reproduces the digital video data output from the control unit 307, and displays the entrance video. When the digital video data output from the control unit 307 is data obtained by performing a predetermined moving image compression process, the predetermined video expansion process is performed on the data to display a video.

  The control unit 307 controls each unit of the extension monitor 300. In addition, the control unit 307 outputs to the transmission driver 310 and the reception driver 311 a switching control signal (SW CON) instructing a transmission period that permits transmission and a reception period that permits reception.

  The first clock generation unit 331 of the control unit 307 is a clock for sampling received data, and is based on crystal oscillation and has a first frequency (for example, 48 MHz (n = 10)) clock (CLK) is generated and output to the synchronization detector 313 and the second clock generator 314.

The packet generation unit 332 of the control unit 307 generates an uplink packet for realizing a call with video. Specifically, the packet generation unit 332 appropriately divides the digital audio data output from the audio I / F unit 305 and writes the digital audio data in the user data field of each slot. Hereinafter, the control data including the “own device ID _monitor ” and the ID _master is written in the control data field of each slot. Further, the packet generation unit 332 writes preamble data and a sync pattern in each slot, and generates an uplink packet (transmission data). Further, the packet generation unit 332 generates a transmission enable signal (SSCS) and a transmission second frequency (for example, 4.8 MHz) clock (SSCK). Then, the packet generation unit 332 outputs the uplink packet to the transmission data processing unit 308 in synchronization with the transmission enable signal (SSCS) and the clock (SSCK).

  Note that the packet generation unit 332 does not generate an uplink packet in a standby state in which data is not transmitted / received between the extension monitor 300 and the intercom base unit 200. Further, when a predetermined event such as operation of a call button occurs in a standby state (during asynchronous communication), the packet generation unit 332 transmits an uplink packet (interrupt signal) in which preamble data, sync pattern, and control data are written. Generate. The preamble and sync pattern used in the interrupt signal during asynchronous communication are the same as those used during synchronous communication.

When the data reproduction unit 333 of the control unit 307 receives the enable signal (SSCS) from the synchronization detection unit 313, the data reproduction unit 333 uses the second frequency clock (SSCK) output from the second clock generation unit 314, and receives the data inversion unit. The downlink signal output from 312 is demodulated to obtain a downlink packet. Then, the data reproducing unit 333 outputs the digital video data included in the downlink packet to the display unit 306, outputs the digital audio data included in the downlink packet to the audio I / F unit 305, and the sync pattern included in the downlink packet. Is output to the connection state detection unit 334. Note that the data reproduction unit 333 causes the identifier storage unit 315 to store its own ID _monitor and ID _master included in the downlink packet at the time of initial registration.

  In addition, when a predetermined event occurs in a standby state (during asynchronous communication) and a downlink signal (interrupt signal) is input, the data reproduction unit 333 demodulates the downlink signal to acquire a downlink packet, and is included in the downlink packet The sync pattern is output to the connection state detection unit 334. The data reproducing unit 333 extracts the control data of the interrupt signal after confirming that the connection state detecting unit 334 has correctly captured the interrupt signal. If the control data is a synchronization request, the extension monitor 300 shifts to a synchronization process with the doorphone parent device 200.

  The connection state detection unit 334 of the control unit 307 stores the normal connection check sync pattern and the reverse connection check sync pattern, and converts the received data sync pattern output from the data reproduction unit 333 into the normal connection check sync pattern and Match with reverse connection check sync pattern. The connection state detection unit 334 determines that the two-wire cable is correctly connected when the sync pattern of the received data completely matches the sync pattern for the normal connection check, and the sync pattern of the received data and the sync pattern for the reverse connection check If the two completely match, it is determined that the two-wire cable is reversely connected. Then, the connection state detection unit 334 outputs an inversion control signal (INV CON) indicating the determination result to the transmission data inversion unit 309 and the reception data inversion unit 312.

  When the transmission data processing unit 308 receives the enable signal (SSCS) from the packet generation unit 332, the transmission data processing unit 308 uses the second frequency clock (SSCK) output from the packet generation unit 332, and the uplink data output from the packet generation unit 332. Modulation processing is performed on the packet data to generate an uplink signal, which is output to the transmission data inverting unit 309.

  When the connection state detection unit 334 determines that the two-wire cable is reversely connected, the transmission data inversion unit 309 inverts the uplink signal output from the transmission data processing unit 308 and outputs the inverted signal to the transmission driver 310. On the other hand, the transmission data inverting unit 309 outputs the uplink signal output from the transmission data processing unit 308 to the transmission driver 310 as it is when the connection state detection unit 334 determines that the two-wire cable is a normal connection.

  The transmission driver 310 transmits an upstream signal to the intercom base unit 200 via the cable connection unit 301 in the transmission section instructed by the switching control signal (SW CON) from the control unit 307.

  The reception driver 311 receives the downlink signal transmitted from the doorphone master device 200 via the cable connection unit 301. Then, the reception driver 311 outputs the downlink signal to the reception data inversion unit 312 in the reception period instructed by the switching control signal (SW CON) from the control unit 307.

  When the connection state detection unit 334 determines that the two-wire cable is reversely connected, the reception data inversion unit 312 inverts the downlink signal output from the reception driver 311 so as to invert the synchronization detection unit 313 and the second clock generation unit. 314, and output to the data reproduction unit 333. On the other hand, when the connection state detection unit 334 determines that the two-wire cable is a positive connection, the reception data inversion unit 312 directly uses the downlink signal output from the reception driver 311 as the synchronization detection unit 313 and the second clock generation unit. 314, and output to the data reproduction unit 333.

  The synchronization detection unit 313 uses the first frequency clock (CLK) output from the first clock generation unit 331 and uses the preamble data included in the downlink signal output from the reception driver 311 to Synchronization (start timing of each bit of received data) is detected. Then, the synchronization detection unit 313 outputs a trigger signal serving as a reference for starting clock output to the second clock generation unit 314 at the timing when the unique pattern of the preamble data is detected, and an enable signal (SSCS) that permits the data reproduction operation Is output to the data reproduction unit 333.

  The second clock generation unit 314 corresponds to the bit rate of the received data based on the first frequency clock (CLK) output from the first clock generation unit 331 at the timing instructed by the synchronization detection unit 313. A clock (SSCK) having two frequencies (for example, 4.8 MHz) is generated and output to the data reproducing unit 333.

The identifier storage unit 315 stores the own device ID _monitor and the ID _master received from the intercom master device 200.

  Although not shown in the figure, the front door device 100, the doorphone master device 200, and the extension monitor 300 are, for example, a CPU (Central Processing Unit), a storage medium such as a ROM (Read Only Memory) storing a control program, a RAM (Random Access), and the like. And a communication circuit. In this case, the function of each unit described above is realized by the CPU executing the control program.

<Example of modulation processing>
Next, an example of modulation processing performed by the transmission data processing unit 108 (208, 308) will be described with reference to FIGS. 6 and 7 show a case where the Manchester code is employed.

  The transmission data processing unit 108 (208, 308) generates one signal corresponding to each data (1 bit) of the packet for each cycle Tm. When the Manchester code is employed, the transmission data processing unit 108 (208, 308) generates a modulation signal 402 by causing the data 401 having the value “0” to rise from Low to High as shown in FIG. . Also, the transmission data processing unit 108 (208, 308) causes the data 411 having the value “1” to fall from High to Low, and generates a modulated signal 412.

  Then, as shown in FIG. 7, for the data string 421 of “0, 0, 1,..., 1, 0”, the transmission data processing unit 108 (208, 308) corresponds to the value of each bit. Thus, a modulation signal 422 having a rising edge or a falling edge is generated every period Tm.

<Example of preamble data>
Next, an example of preamble data used in the present embodiment will be described with reference to FIG.

  As shown in FIG. 8, the preamble data (4 bytes = 32 bits) used in the present embodiment has a pattern of “0” from the first byte to the third byte, and the fourth byte is “0” from the beginning. ", The last 1 bit is a pattern of" 1 ". As a result, the preamble data shown in FIG. 8 has a unique pattern in which the H (High) period is longer than the others in the 7th and 8th bits (the 31st and 32nd bits from the beginning) of the 4th byte.

  When the two-wire cable is reversely connected, if the inversion processing is not performed in the transmission side device, the preamble data is L (Low) in the 7th and 8th bit portions of the 4th byte when received by the reception side device. This is a unique pattern with a longer period than others.

<Internal configuration of synchronization detector>
Next, the details of the internal configuration of the synchronization detection unit 113 of the front door device 100 will be described with reference to FIG. In the description, FIG. 10 is used in conjunction with FIG. 9 in order to facilitate understanding of the synchronization detection processing of the present embodiment. In the example of FIG. 10, the preamble data and its unique pattern are those shown in FIG.

  As illustrated in FIG. 9, the synchronization detection unit 113 includes a first unique pattern detection unit 151, a second unique pattern detection unit 152, and an enable signal generation unit 153.

  The first unique pattern detection unit 151 stores a check unique pattern (hereinafter referred to as “positive connection check unique pattern” (in the example of FIG. 9, [HHHLLLLLLL])) when the two-wire cable is positively connected. ing. Then, the first unique pattern detection unit 151 samples the preamble data included in the reception data output from the reception data output from the reception data inversion unit 112 with the clock of the first clock generation unit 131, and performs a positive connection. The sampling value corresponding to the number of check unique patterns is collated with the unique pattern for positive connection check. The first unique pattern detection unit 151 determines that the unique pattern has been detected when the sampling value and the unique pattern for the positive connection check completely match, and outputs a signal indicating that to the enable signal generation unit 153. In the example of FIG. 10, ten sampling values in the sample section 501 completely match the unique pattern for positive connection check. FIG. 10 shows a case where the first clock generation unit 131 generates a 48 MHz clock (CLK) and the second clock generation unit 114 generates a 4.8 MHz clock (SSCK).

  The second unique pattern detection unit 152 is a reverse pattern of the unique pattern for normal connection check, and a unique pattern for check when the two-wire cable is reversely connected (hereinafter referred to as “reverse connection check unique pattern”). ([LLLHHHHHHH] in the example of FIG. 9)) is stored. The second unique pattern detection unit 152 samples the preamble data included in the reception data output from the reception data inversion unit 112 at the same timing as the first unique pattern detection unit 151, and reversely connects the sampling value. Check unique patterns for checking. The second unique pattern detection unit 152 determines that the unique pattern has been detected when the sampling value and the reverse connection check unique pattern completely match, and indicates a signal indicating this (in the example of FIG. 10, the SSCS L (Low) signal) is output to the enable signal generation unit 153.

  When the enable signal generation unit 153 receives a signal indicating that a unique pattern has been detected from either the first unique pattern detection unit 151 or the second unique pattern detection unit 152, the trigger that becomes a reference for starting clock output The signal is output to the second clock generation unit 114, and an enable signal for permitting the data recovery operation is output to the data recovery unit 133 of the control unit 107.

  In this case, the second clock generation unit 114 has a first frequency clock (t0 in FIG. 10) after a predetermined number of clocks (section 502 in FIG. 10) from the timing when the trigger signal is input from the enable signal generation unit 153. Is used as a start timing to generate a clock. In the example of FIG. 10, since SSCK is a clock obtained by dividing CLK by 10, the prescribed number of clocks is “10”.

  The internal configurations of the synchronization detection unit 213 of the doorphone master unit 200 and the synchronization detection unit 313 of the extension monitor 300 are also the same as the internal configuration of the synchronization detection unit 113 of the front door device 100 shown in FIG.

<Flow of synchronization detection processing>
Next, the flow of the synchronization detection process in the entrance cordless handset 100 (synchronization detection unit 113, connection state detection unit 134) will be described with reference to FIG.

  In step S <b> 610, the synchronization detection unit 113 uses the first unique pattern detection unit 151 and the second unique pattern detection unit 152 to output the downlink before demodulation output from the reception driver 111 using the clock of the first clock generation unit 131. The preamble data included in the signal is sampled, and the unique pattern of the preamble data is checked.

  If the unique pattern can be detected (S620: YES), the flow proceeds to step S630 on the assumption that the bit synchronization can be established. If not detected (S620: NO), the flow returns to step S610 to return to the unique pattern. Check again.

  In step S630, the connection state detection unit 134 checks the sync pattern of the reception data output from the data reproduction unit 133.

  If the sync pattern of the received data matches the sync pattern for normal connection check (S640: YES), in step S650, the connection state detection unit 134 determines that the two-wire cable is a normal connection, and performs synchronization detection processing. finish.

  When the sync pattern of the received data matches the sync pattern for reverse connection check (S640: NO, S660: YES), in step S670, the connection state detection unit 134 determines that the two-wire cable is reverse connected. Then, the synchronization detection process ends.

  If the sync pattern of the received data does not match either the reverse connection check sync pattern or the reverse connection check sync pattern (S640: NO, S660: NO), the connection state detection unit 134 in step S680. Determines that the sync pattern detection has failed, returns the flow to step S610, and checks the unique pattern again.

<Sequence until initial registration>
Next, a sequence until initial registration according to an embodiment of the present disclosure will be described with reference to FIG.

  When the entrance cordless handset 100 and the doorphone master set 200 are connected with a two-wire cable and the power is turned on (S701), the doorphone master set 200 writes registration start information in the control data field for the entrance cordless handset 100. The interrupt signal is transmitted (S702).

  The front door device 100 captures the interrupt signal from the door phone master device 200 and checks the control data (registration start information) of the interrupt signal (S703). The capture of the interrupt signal specifically means that the interrupt signal is sampled using the first frequency clock, the unique pattern in the preamble is detected, bit synchronization is established, and the second frequency clock is set. It is used to reproduce the interrupt signal and detect the sync pattern.

  Further, the entrance unit 100 detects the inversion of the two-wire cable (judgment of normal connection / reverse connection) using the sink pattern of the interrupt signal, and when the two-wire cable is in the reverse connection, the transmission data inversion unit 109 Then, inversion setting is performed for the reception data inversion unit 112 (S704).

  Thereafter, the front door device 100 transmits an interrupt signal in which the confirmation of receipt of the registration start information is written in the control data field to the intercom base device 200 (S705).

  The intercom master device 200 captures the interrupt signal from the entrance slave device 100 and confirms the control data (registration start information receipt) of the interrupt signal (S706).

  Then, the intercom master device 200 transmits an interrupt signal in which the unique identifier (terminal ID) assigned to the front door slave device 100 is written in the control data field (S707).

  The front door device 100 confirms the control data (terminal ID) of the interrupt signal, and transmits the interrupt signal in which the receipt confirmation of the terminal ID is written in the control data field to the doorphone master device 200 (S708).

  Through the above processing, the initial registration is completed (S709).

<Sequence from standby state to communication state>
Next, a sequence from a standby state (during asynchronous communication) to a communication state according to an embodiment of the present disclosure will be described with reference to FIG. FIG. 13 shows a sequence in the case where the front cordless handsets 100-1 and 100-2 and the extension monitor 300 are connected to the doorphone master phone 200.

  In a standby state (at the time of asynchronous communication) in which data is not transmitted / received between each device and the door phone master unit 200 (S801), when the call button of the entrance slave unit 100-2 is operated (S802), the entrance slave unit 100- 2 performs a synchronization request by transmitting an interrupt signal in which the synchronization request is written in the control data field to the intercom base unit 200 (S803).

  The intercom master device 200 captures the interrupt signal (S804) and confirms the synchronization request included in the interrupt signal. The capture of the interrupt signal specifically means that the interrupt signal is sampled using the first frequency clock, the unique pattern in the preamble is detected, bit synchronization is established, and the second frequency clock is set. It is used to reproduce the interrupt signal and detect the sync pattern.

  Upon confirming the synchronization request from the entrance slave device 100-2, the intercom master device 200 determines the frame timing for synchronous communication with each device (S805), and transmits a synchronization slot signal to each device (S806).

  Each device synchronizes with the doorphone master device 200 in accordance with the synchronization slot signal (S807). As a result, the respective devices and the intercom master device 200 are in a synchronized state (S808).

  Thereafter, the front door device 100-2 makes an image connection request by transmitting an upstream packet in which the image connection request is written in the control data field to the parent device 200 (S809). When confirming the image connection request, the door phone main unit 200 confirms the image connection by transmitting the downlink packet in which the image connection confirmation is written in the control data field to the front door device 100-2 (S810). Thereafter, the entrance handset 100-2 transmits image data to the doorphone master 200 by an uplink packet, and the doorphone master 200 enters an image data communication state in which the image data is displayed (S811). Note that the image data transmitted from the front door slave 100-2 is broadcast from the doorphone master 200 to other devices (the front door slave 100-1, the extension monitor 300). Can be displayed.

<Operation of each device>
Next, the operation of each device will be described.

<Operation of entrance cordless handset>
FIG. 14 is a flowchart illustrating an example of the operation of the front door device 100.

  In step S1010, the control unit 107 determines whether the call button has been operated. When the call button is operated (S1010: YES), the control unit 107 advances the flow to step S1020, and when not operated (S1010: NO), advances the flow to step S1100 described later.

  In step S <b> 1020, control unit 107 transmits a calling signal to door phone parent device 200.

  In step S1030, control unit 107 determines whether a response signal has been received from intercom master device 200 or not. When the response signal is not received (S1030: NO), the control unit 107 returns the flow to step S1020, and when the response signal is received (S1030: YES), the control unit 107 advances the flow to step S1040. Note that if the control unit 107 does not receive a response signal even if the call signal is transmitted a predetermined number of times, the control unit 107 may advance the flow to step S1100 described later.

  In step S <b> 1040, the control unit 107 starts audio input and video shooting using the microphone 104, the audio I / F unit 105, and the camera unit 106. In addition, the control unit 107 uses the packet generation unit 132 and the transmission data processing unit 108 to start packetizing and encoding various data (control data / digital audio data / digital video data) to be transmitted. Note that the control unit 107 may perform transmission rate control of digital audio data and digital video data.

  In step S1050, control unit 107 determines whether or not it is a slave unit side transmission section. If it is a transmission interval (S1050: YES), the control unit 107 advances the flow to step S1060. If not (S1050: NO), the control unit 107 advances the flow to step S1070 described later.

  In step S <b> 1060, control unit 107 uses transmission driver 110 to transmit the upstream signal generated by encoding to door phone parent device 200 via a two-wire cable. In addition, the control part 107 stops transmission of an uplink signal when a transmission area is complete | finished.

  In step S1070, control unit 107 determines whether or not it is a parent device side transmission section. When it is a transmission section (S1070: YES), the control unit 107 advances the flow to step S1080. When it is not a transmission section (S1070: NO), the control section 107 advances the flow to step S1090 described later.

  In step S1080, the control unit 107 starts receiving a downlink signal, extracting various data (control data / audio data), and outputting audio. Note that the control unit 107 stops receiving a downlink signal or extracting various data when the transmission period ends.

  In step S <b> 1090, control unit 107 determines whether or not the call between entrance slave device 100 and doorphone master device 200 has ended. For example, the control unit 107 determines that the call has ended when it receives a signal indicating that a call end operation has been performed on the doorphone base unit 200 from the doorphone base unit 200. If the call has not ended (S1090: NO), control unit 107 returns the flow to step S1050. If the call has ended (S1090: YES), control proceeds to step S1100.

  In step S1100, control unit 107 determines whether or not an instruction to end processing related to the door phone function has been given. For example, when the control unit 107 receives a signal indicating that the operation of stopping the door phone function has been performed on the doorphone master unit 200 from the doorphone master unit 200, the control unit 107 determines that the end of the process has been instructed. If the end of the process is not instructed (S1100: NO), the control unit 107 returns the flow to step S1010, and if instructed to end the process (S1100: YES), ends the series of processes.

<Operation of doorphone master unit>
FIG. 15 is a flowchart showing an example of the operation of the doorphone parent device 200.

  In step S2010, the control unit 207 determines whether a call signal has been received from the front door device 100. When the call signal is received (S2010: YES), the control unit 207 advances the flow to step S2020. When the call signal is not received (S2010: NO), the control unit 207 advances the flow to step S2090 described later.

  In step S2020, the control unit 207 transmits a response signal to the front door device 100 and outputs a ringing tone using the voice I / F unit 205 and the speaker 203.

  In step S2030, the control unit 207 starts voice input using the microphone 204 and the voice I / F unit 205. In addition, the control unit 207 uses the packet generation unit 232 and the transmission data processing unit 208 to start packetizing and encoding various data (control data / digital audio data) to be transmitted. Note that the control unit 207 may perform digital audio data transmission rate control.

  In step S2040, control unit 207 determines whether or not it is a slave unit side transmission section. The control unit 207 advances the flow to step S2050 if it is a transmission interval (S2040: YES), and advances the flow to step S2060 described later if it is not a transmission interval (S2040: NO).

  In step S2050, the control unit 207 starts receiving an upstream signal and extracting various data (control data / audio data / video data). In addition, the control unit 207 uses the audio I / F unit 205, the speaker 203, and the liquid crystal display to start outputting audio and video. Note that the control unit 207 stops receiving the uplink signal or extracting various data when the transmission period ends.

  In step S2060, the control unit 207 determines whether or not it is a parent device side transmission section. When it is a transmission section (S2060: YES), the control unit 207 advances the flow to step S2070. When it is not a transmission section (S2060: NO), the control section 207 advances the flow to step S2080 described later.

  In step S2070, the control unit 207 uses the transmission driver 210 to transmit the downlink signal generated by encoding to the front door device 100 via the two-wire cable. However, it is desirable that the control unit 207 does not transmit digital audio data until the response button is operated as described above. Note that the control unit 207 stops the transmission of the downlink signal when the transmission period ends.

  In step S2080, control unit 207 determines whether or not the telephone conversation between entrance slave device 100 and doorphone master device 200 has ended. For example, the control unit 207 determines that the call is ended when it is detected that an operation for ending the call is performed on the intercom base unit 200. In addition, it is desirable that the control unit 207 transmits a signal indicating that to the entrance terminal 100 when an operation for terminating the call is performed. If the call has not ended (S2080: NO), control returns to step S2040. If the call has ended (S2080: YES), control proceeds to step S2090.

  In step S2090, control unit 207 determines whether an instruction to end the process related to the door phone function has been given. For example, when the control unit 207 detects that the doorphone function stop operation has been performed on the doorphone master unit 200, the control unit 207 determines that the end of the process has been instructed. In addition, when the operation of stopping the door phone function is performed, the control unit 207 desirably transmits a signal indicating that to the front door device 100. If the control unit 207 is not instructed to end the process (S2090: NO), the control unit 207 returns the flow to step S2010, and if instructed to end the process (S2090: YES), ends the series of processes.

<Routing control during normal operation>
Next, a specific example of routing control during normal operation of door phone parent device 200 according to the present embodiment will be described with reference to FIG. In the example of FIG. 16, the intercom base unit 200 (control unit 207 (described as “base unit control unit” in FIG. 16)) is one of the DRVs (set of transmission driver (Tx) and reception driver (Rx)) 1 ˜5, a case where five devices (the entrance slave device 100, the extension monitor 300, and the parent device of another door phone system) are connected is shown. In this case, seven types of setting patterns (P1 to P7) are prepared.

  The setting pattern P1 indicates routing (valid / invalid of communication route) in a standby state in which the intercom base unit 200 is not transmitting / receiving data to / from any device. In the setting pattern P1, the intercom base unit 200 is in a reception mode (a mode in which only reception is performed without transmission), and the control unit 207 receives the reception driver (for each DRV so that data can be received from each device). Rx) is enabled.

  When an asynchronous interrupt signal is received from any device in the standby state, door phone parent device 200 establishes synchronization with the device that transmitted the interrupt signal. For example, when receiving an interrupt signal from DRV1, door phone parent device 200 establishes synchronization with a device connected to DRV1, and transmits and receives data (shifts to P2 (during transmission) or P3 (during reception)).

  The setting pattern P2 indicates routing at the time of simultaneous transmission (Broadcast) in which the doorphone parent device 200 transmits data to all devices. In the setting pattern P2, the intercom base unit 200 is in a transmission mode (a mode in which only transmission is performed without reception), and the control unit 207 is configured to transmit each DRV with a transmission driver ( Tx) is enabled. At this time, even if data is transmitted from any device to the intercom base unit 200, the base unit 200 discards the data. In the setting pattern P2, the intercom base unit 200 transmits data to all connected devices, but only the identifier of the communication partner device is described in the control data field of the downstream packet. Other devices discard data even if they are received.

  Setting patterns P3 to P7 indicate routing at the time of individual reception in which the intercom master device 200 receives data from any one device. In the setting patterns P3 to P7, the intercom master device 200 is in the reception mode, and the control unit 207 enables one DRV reception driver (Rx) corresponding to each setting pattern and sets other DRV transmission drivers (Tx). To enable. Thereby, the intercom base unit 200 outputs the data received from the DRV for which the reception driver (Rx) is selected to the control unit 207 (CPU) in the routing control unit 212, and at the same time, transmits the data as it is to the transmission driver ( Tx) can be broadcast to other devices connected to all selected DRVs. Therefore, it is not necessary to decode and analyze the received data when performing broadcast transmission.

<Routing control during initial registration>
Next, a specific example of routing control at the time of initial registration of door phone parent device 200 according to the present embodiment will be described with reference to FIG. In the example of FIG. 17, the case where the doorphone master unit 200 (the control unit 207 (described as “master unit control unit” in FIG. 17)) is connected to five devices via any one of the DRVs 1 to 5. Show. In this case, five types of setting patterns (EP1 to EP5) are prepared.

  The setting patterns EP1 to EP5 indicate routing at the time of initial registration in which any one device is registered by the doorphone parent device 200. In the setting patterns EP1 to EP5, the intercom base unit 200 is in the transmission mode, and the routing control unit 212 does not transmit packets to devices other than the registration target in the section in which packets are transmitted to the registration target devices. It transmits only to the registration target device connected to the DRV transmission driver (Tx). At this time, the other DRV reception driver (Rx) is enabled, but when the doorphone main unit 200 is transmitting, the routing control unit 212 has a logic to block reception of packets from all devices, Reception of packets from those DRVs is not accepted (disable mode). Note that the settings from P3 to P7 in FIG. 16 are used for transmission of packets from each registration target device to the intercom master device 200. In this case, the broadcast transmission function to other connected devices works, but since the transmission is only to the doorphone parent device 200, the other connected devices ignore this. Thereby, door phone main unit 200 can communicate one-to-one with a registration target device such as each front unit 100. In this state, door phone master device 200 transmits a packet including an identifier and a transmission cycle unique to registration-target entrance slave device 100. Thereby, since the packet is received only by the entrance slave device 100 to be registered, a unique identifier and transmission cycle can be set for each entrance slave device.

<Avoiding collisions in the asynchronous state>
Next, collision avoidance in the asynchronous state according to the present embodiment will be described with reference to FIGS. FIG. 18 is a diagram illustrating an example of a table in the identifier storage unit 215 of the doorphone master device 200, and FIG. 19 is a diagram illustrating collision avoidance in an asynchronous state of the doorphone system.

  As shown in FIG. 18, intercom base unit 200 stores identifiers (device IDs), transmission cycles, and slot allocation information (transmission slots) for the own device and each connected device in identifier storage unit 215. The intercom base unit 200 transmits the set device ID, transmission cycle, and slot allocation information to each device. For example, door phone master device 200 transmits device ID: ID1, transmission cycle: 1 ms, transmission slot: SL3 to door unit 100-1, and device ID: ID3 to door unit 100-3. , Transmission cycle: 3 ms, Transmission slot: SL5 is transmitted. The entrance slave device 100-1 and the entrance slave device 100-3 store the received information in the identifier storage unit 115.

  Then, in the asynchronous state, it is assumed that the call buttons of the entrance slave device 100-1 and the entrance slave device 100-3 are operated almost simultaneously. In this case, as shown in FIG. 19, the front door slave 100-1 transmits a synchronization request n times with a transmission cycle of 1 ms, and the transmission front door slave 100-3 transmits a synchronization request n times with a transmission cycle of 3 ms. (N = 3 in FIG. 19). As is clear from FIG. 19, the first synchronization request is transmitted from the entrance slave device 100-1 and the entrance slave device 100-3 at the same time, so that a collision occurs, but the entrance slave device 100-1 and the entrance child are collided. Since the transmission cycles of the machine 100-3 are different from each other, the second and subsequent synchronization requests have different transmission timings, and collision is avoided. Therefore, the intercom master device 200 can reliably receive the synchronization request and can shift to the communication state with the entrance slave device 100-1 and the entrance slave device 100-3 in a short time.

  In the synchronized state, each device transmits a call signal in different transmission slots indicated in the slot allocation information, so that no collision occurs.

<Effects of the present embodiment>
As described above, according to the present embodiment, when a predetermined event such as an operation of a call button is performed in a plurality of devices almost simultaneously in an asynchronous state, each device has a transmission cycle different from each other. Since the synchronization request is transmitted a plurality of times, it is possible to shift to the communication state in a short time without continuous synchronization request collisions. In the present embodiment, the connection between connected devices such as the doorphone master device 200 and the entrance slave device 100 has been described as an example, but the present invention is not limited to this. For example, the same effect can be obtained even if the other application device is a control device (communication device) such as a business phone (between an extension telephone and a control device) or a home security device (between various sensor nodes and a control device). .

  The present disclosure is suitable for use in a door phone system including an entrance child device with a camera and a door phone parent device.

DESCRIPTION OF SYMBOLS 1 Door phone system 100 Entrance unit 101, 201, 301 Cable connection part 102, 202, 302 Key input part 103, 203, 303 Speaker 104, 204, 304 Microphone 105, 205, 305 Audio | voice I / F part 106 Camera part 107, 207, 307 Control unit 108, 208, 308 Transmission data processing unit 109, 209, 309 Transmission data inversion unit 110, 210, 310 Transmission driver 111, 211, 311 Reception driver 112, 312 Reception data inversion unit 113, 213, 313 Synchronization Detection unit 114, 214, 314 Second clock generation unit 115, 215, 315 Identifier storage unit 131, 231, 331 First clock generation unit 132, 232, 332 Packet generation unit 133, 233, 333 Data reproduction unit 134, 234, 334 Connection state detection unit 151 First unique pattern detection unit 152 Second unique pattern detection unit 153 Enable signal generation unit 200 Door phone master unit 206, 306 Display unit 212 Routing control unit 235 Identifier setting unit 300 Additional monitor

Claims (4)

The slave unit of the door phone system in which a master unit and a slave unit are connected via a two-wire cable, and transmits and receives packet signals by time division duplex between the master unit and the slave unit,
A receiving unit for receiving data from the base unit;
A storage unit for storing an identifier assigned by the parent device included in the received data;
A transmission unit for transmitting data to the base unit;
Comprising
The transmission unit transmits a synchronization request to the parent device a plurality of times in a transmission cycle uniquely determined by the identifier in an asynchronous state with the parent device.
Cordless handset. A slave unit connected to the master unit and transmitting / receiving packet signals to / from the master unit,
A receiving unit for receiving data from the base unit;
A storage unit for storing an identifier assigned by the parent device included in the received data;
A transmission unit for transmitting data to the base unit;
Comprising
The transmission unit transmits a synchronization request to the parent device a plurality of times in a transmission cycle uniquely determined by the identifier in an asynchronous state with the parent device.
Cordless handset. It is a monitor that is added to a door phone system consisting of a master unit and a slave unit,
A receiving unit for receiving data from the base unit;
A storage unit for storing an identifier assigned by the parent device included in the received data;
A transmission unit for transmitting data to the base unit;
Comprising
The transmission unit transmits a synchronization request to the parent device a plurality of times in a transmission cycle uniquely determined by the identifier in an asynchronous state with the parent device.
monitor. The master unit and the other devices are connected via a 2-wire cable, a communication method of the intercom system for transmitting and receiving packet signals by time division duplexing between the other device and the base unit,
The master unit is
Transmitting data including an identifier unique to the other device and a transmission period uniquely determined by the identifier;
The other device is
In the master unit and the asynchronous state, and transmits a plurality of times the synchronization request to the base unit in front Kioku Shin cycle,
Communication method.

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