JPH02241292A - Information and communication systems, their information and communication terminals, and switching devices - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The invention is - Audemeo video equipment and telephones.

The present invention relates to an information communication system using a switching device for setting a signal transmission path between terminal devices such as communication devices such as personal computer communication terminals, and the information communication terminal and switching device.

BACKGROUND OF THE INVENTION Conventionally, signal transmission paths between terminal devices such as multiple audio/video devices and communication devices, i.e., connectors of switching devices that determine signal connections between devices, include:
There were connectors for televisions, VTRs, video discs, tape drives, tuners, amplifiers, telephones, etc., and each connector was labeled with the name of the various devices mentioned above. When assembling the system, it was necessary to make connections while making sure that the device name written on the connector matched the device name to be connected.

In other words, the connection between devices is left up to the user, and even if a connection is made incorrectly, the devices cannot issue an error message at all.

Problems to be Solved by the Invention When considering the connection between terminal devices such as conventional audio/video devices and communication devices - for example, video tape recorder A and video tape recorder B6 vanes, the signal lines required for the connection are as follows. There are inputs and outputs for the video signal, audio right signal, and audio left signal, so there are six in total. All these connectors have a common R
It is CA Bin Jack. FIG. 9 shows the connectors on the rear panels of the video tape recorders 60 and 60. Video output 61 of video tape recorder 60. Audio pressure output 6
2. Each connector of the audio right output 63 is connected to the video output 61 of the video tape recorder 6o. The audio input 62° is connected to each coil lid of the audio window input 63, and the video input 64 of the video tape recorder 60 is connected. The audio input 66 and audio window input 66 connectors are connected to the video output 64 of the video tape recorder 60. It is necessary to connect to the audio left output 66 and audio window output 66 connectors. Also, the connection between the output connector and the input coil/lid for video signal to video signal, audio left signal to audio left signal, and audio right signal to audio right signal is correct.
If you intended to connect to the input 1 side but ended up connecting it to the input 2 side, you would not be able to record if you set the recording signal source switch on the front panel to manual 1 and set the 6 vanes after one connection.

In the above example, each device has a switching function that switches the signal connection between devices.
Even in a system in which the switching device controls the connection of all signals, the connection between the switching device and each device requires device-to-coil, lid multi-signal to coil-to-coil, etc., as in the example above. A complicated operation to confirm the lid name is required.

The present invention has focused on the above-mentioned problem, and in a system in which various signal lines of terminal devices of an information communication system are collected in a one-way switching device, the connection of the switching device to the connector is performed regardless of the type of the terminal device and the signal line. An object of the present invention is to provide an information communication system, an information communication terminal, and a switching device in which a switching device can correctly switch signals between one terminal device even when freely connected to any connector.

Means for Solving the Problems The present invention provides a DC current detection unit that detects when a DC current flows through a switching device to an audio/video signal line of a terminal device, and a DC current detection unit that detects this DC current detection page 7. a communication control unit having a function of receiving the output of the unit and generating and transmitting a communication message containing the identification code of the Ippaku terminal device and information indicating the characteristics of the audio/video signal line through which the direct current flows;
The switching device includes a switching unit that forms a transmission path for audio/video signals between terminal devices, and a DC loop forming a current path for passing a DC current to any audio/video signal line that enters the switching unit. The information communication system includes a communication control section that communicates with another terminal device via a control information communication line and controls the switching section and the DC loop forming section.

Effects of the present invention With the above-described configuration, the switching device of an information communication system such as audio/video communication can determine which connector is connected to which signal line, which device is connected to, or which connector is connected to which signal line. - Users are free to identify which signal line belongs to which device, and do not have to check each device name or signal name one by one when connecting terminal devices such as audio/video communications and switching devices. The connection cable can be connected to the connector of the switching device.

Embodiment FIG. 1 shows an example of the connection between a switching device and a terminal device for audio/video communication in an information communication system for audio/video communication, etc., according to an embodiment of the present invention.

1 is a switching device. , 2 is a communication control unit provided in the switching device 1, and is composed of a microgrossing unit (MPU) that controls communication processing and other peripheral circuits. 3 is a memory section that can be read/written from the communication control section 2; Reference numeral 4 denotes an address setting section for setting an address in the communication control section 2. , 6 is the DC loop forming part -6
is a switching section. , 7 is a driver/receiver unit for electrically matching the signal level on the control information communication line 21 and the signal level input/output by the communication control unit 2, -7a is a transmission buffer, and 7b is a reception buffer. 8 is a choke coil for cutting off AC signals other than DC. 9 is resistance. 1o is a multi-contact switch whose contacts are switched by the MPU3. , 11 is a switching instruction input section, through which the user sets the connection between the audio/video communication devices. An output signal from the switching instruction input section 11 is input to a communication control section 2 . 12, 13, 14, 15, 1
6, 17, 18 and 19 are audio/video signal line connectors attached to the rear panel of the switching device 1, all of which are RCA bin jacks of the same shape. The switching device 1 is connected to each of these connectors 12 to 19.
A signal M12a is sent to the internal switching section 6 of the .

13a, 14a, 16a, 16a, 17a.

18a and 19a are connected. The switching unit 6 is controlled by the communication control unit 2 and has a function of freely connecting and disconnecting the signal lines 12a to 19a. Furthermore, the signal lines from the connectors 12 to 19 are connected to each contact T2k), 13b, 14b of the multi-contact switch 1o of the DC loop forming part 6.
, IE5b, 16t).

17b, 18b and 19b. Many 1 o
The page contact switch 1o is normally located at a contact 20 that is not connected to anything, but under the control of the communication control unit 2, it is located at any contact 12b to 19b connected to the signal lines 12a to 19a.
can be connected to.

22 is a video disc player, and the video output 12d of the video disc 22 is connected to the connector 12 of the switching device 1 by a connecting cable 120, and the audio left output 1 is similarly connected to the connector 12 of the switching device 1.
4d is connected to the connector 14 by the connecting cable 14Q,
The right audio output 15d is connected to the connector 16 by a connection cable 150. , 22& is a communication control unit, 22
1) is a direct current detection section. , 23 is an audio amplifier, and the audio input port 17d of the audio amplifier 23 is connected to the connector 17 of the switching device 1 by a connecting cable T7C, and the audio right input 18d is similarly connected to the connector 18 by a connecting cable T8c. There is.

23a is a communication control section, and 23b is a direct current detection section.

24 is a video monitor, and the video monitor 24 has a video monitor 1
9d is connected to the connector 19 of the switching device 1 by a connecting cable 19c.

11 Vane 24a is a communication control section, and 241) is a DC current detection section. 220, 230 and 24Q are driver receiver sections, and 22d, 23d and 24d are address setting sections.

21a, 2Tb, 21c and 21d are connectors for connecting to the information communication line 21.

FIG. 2 is a block diagram clearly depicting a circuit included in a terminal device 39 for audio/video communication, etc., according to an embodiment of the present invention. 26 is a DC current detection section, and -3 input signal lines 33 (1, 34d and 3
6ti and three output signal lines - 36d, 37d and 38
DC current detection elements 331L and 341L are respectively installed in d.
, 36a, 36IL.

37a and 38a are connected and the detection output is 330°34c
, 36c, 36c, 37c and 380 are connected to the communication control section 26. The direct current detection element can be easily constructed by a current mirror circuit, a photocoupler, etc. The communication control section 26 is formed by a microprocessor unit (MPU). 27 is a driver receiver section used for the same purpose as the driver receiver section 7 of the switching device 1 shown in FIG. 1; 27a is a transmission buffer;
7b is a receiving buffer. 28 is an address setting section for setting the address of the communication control section 26.

270 is a connector for connecting a control information communication line. Reference numeral 29 denotes a DC voltage source of approximately 6V, which serves as a source for flowing DC current when a DC loop is formed on the switching device side. 29& is a choke coil that only allows direct current to flow. 130 is an output unit 30a that outputs video signals and audio signals originally provided in the audio video device.

301) and 30C are output drivers. Similarly, 31 is an input unit that receives and receives video signals and audio signals originally provided in the audio/video device, and 31a,
311) and 310 are input buffers. 32a, 3
21) , 320.32d, 326 and 32f are capacitors for cutting DC current, and output drivers 3oa, 30b and 300 and human cover sofas 31a and 3
1b and 31C are capacitors 32a and 321, respectively.
), 320.

13 Beige Output terminal 33d via 32d, 32θ and 32f.

34d and 35d and input terminals 36α, 37d and 38d
It is connected to the.

Next, the operation will be explained.

In the information communication system of one embodiment of the present invention shown in FIG. 1, a video disc player 22. audio amplifier 23
When the switching device 1 is powered on to start up the information communication system, the communication control section 2 of the switching device 1 connects the multi-contact switch 10 of the DC loop forming section 6 from the contact 2o to the signal line t2.
Replace it with a contact 12t) connected to a. Then, the signal line of the video output terminal 12d of the video desulfur player 22 forms a DC loop in the switching device 1. Thereafter, the multi-contact switch 1o of the DC loop forming section 6 of the switching device 1 is sequentially switched from contact 12b to contact 13b and then to contact 191), and when all scanning is completed, it is returned to contact 20. Due to such a scanning operation of the switching device 1, the human output signal lines of each terminal device such as audio video communication form a DC loop one by one, and then return to the original state again. go. The operation when the input/output signal lines form a DC loop will be described using FIG. 2, which is a block diagram of a terminal device such as an audio/video communication device according to an embodiment of the present invention. In FIG. 2, assuming that one output terminal 33 (1) is formed as a DC loop by the scanning operation of the switching device 1, the DC voltage source 29 passes through one DC current detection element 33a and the output terminal 33d forms a DC loop of the switching device 1. Choke coil 8 of section 6
A circuit is created in which current flows up to resistor 9, and direct current flows through - terminal equipment 3 for audio/video communication, etc.
9 flows toward the input/output terminal of the switching device 1. The DC current detection element 33a is connected to one DC voltage source 29.
The current flowing out from the choke coil 29& and output terminal 33d to the outside is detected, and the detection output is input to the communication control section 26. For example - DC current sensing element 33
When 1L detects a current, the detection output 330 changes from LOW level to high level, and the communication control unit 26 receives the level change of this detection output 33C and switches the signal line connected to the output terminal 16 and the terminal 33 (i). We know that a DC loop has been formed by device 1. Here, each audio
The communication control unit 26 of the terminal device 39, such as video communication, has one detection output 3 of each detection element 33iL to 38a.
A conversion table as shown in FIG. 7 is provided internally for deriving an identification code or attribute code for identifying which input terminal or output terminal of the device is assigned from 30 to 380. For example, the detection output 3 of the DC current detection element 33a
When 3C changes from a low level to a high level (active state), the communication control unit 26 checks the row of detection outputs 330 on the left side of part 1, and since -b6 is 1, it outputs a signal b2. bi
, bo is 0.1.0, so it is known that the left audio, that is, the left audio output signal line has been accessed by the switching device 1. Also, when the detection output 38C of the DC current detection element 3B & changes from low level to high level, the communication control unit 26 similarly searches the row of detection output 38C on the left side of Figure 7, and because b7 is 1. Signal human power-b6. b4゜b3 is o,
o, i, it is known that the composite video signal, ie, one composite video input signal line, has been accessed by the switching device 1. When the communication control unit 26 learns that any signal line has been accessed by the switching device 1, it partially sends a communication message 48 as shown in FIG. 3 or a communication message 96 as shown in FIG. Send to 1. This telegram 48
Or 96 is driven by the transmission buffer 27a of the driver/receiver section 27 and placed on the control information communication line 21. In the communication message 48 of FIG. 3, each code is composed of a total of 11 bits: 1 -start bit, 8 data bits, 1 even parity bit, and 1 stop bit. , 40 is a priority code (PR) - indicating the priority level of the communication packet.

41 is a source address (SA), which contains the address of the sender of the communication message. Reference numeral 42 denotes a differential address (DA), which contains the destination address of the communication packet, that is, the other party's address.

43 is a control code (CC) indicating the attributes of the communication message (for example, whether it is a retransmission packet or a 17th page initial transmission packet). 44 is the number of data bytes (BC), which indicates the number of bytes of the data portion. 46 is header (HD)
- type of data (e.g.

(command, status, etc.). The header is considered part of the data section and is added to -BC.

46 is a data section (DATA) in which n 11-bit codes (1 to 264) follow, and commands and status information are entered here. 47 is a frame check code (FCC) which is used to detect transmission errors by inserting a sum check code for each byte from -PR to the last DATA.

In addition, in the communication telegram 95 in FIG. 4, 81 is the communication telegram 9
This is the start bit indicating the beginning of 6, and 0'' is output. 82 is a mode bit indicating the transmission rate of this communication message 96, and one or more bits are transmitted. The lowest transmission rate is called mode 0 and the mode bits are only '0'.The next fastest transmission rate is mode 1 and the mode bits are 'i o' - the even faster transmission rate is mode 2 and the mode bits are 'i o'. The bit becomes +110″.

The 18hage 83 is a master address indicating the source of the communication message 96, and is composed of -12 bits. 84 is an odd parity next to the master address 83.

86 is a slave address indicating the destination of the communication message 96, and is composed of -12 bits. 86 is a (odd number) parity pin following the slave address 86. 87 is an ACK of the response bit that the recipient of this communication message 96 specified by the slave address 86 returns to the sender. (When responding, return "Io+'") The sender is ACK8 with -
Continue sending while checking whether 7 is returned. Reference numeral 88 indicates the nature of this communication message 96 (such as whether the command is a request or data), and is composed of 4 bits. 89 is a parity bit following the control bit 88. Similar to ACK87, 9o is an AGK of a response bit that the receiving destination returns to the transmitting source. 91 is a data bit, which is composed of 8 bits. , 92 is EOD (end off data) indicating whether the data continues.

When EOD is "o", the data is not continued19
When the -EOD is tl 1 ++, it indicates that the data continues. 93 is Cheeta Binodo 91
This is the (odd number) parity bit attached to the sum of EOD92 and EOD92. Similar to ACKs 87 and 90, 94 is an ACK of the response bit that the receiving destination returns to the transmitting source. EOD
While 92 is "t", data bit 91, KOD92
(=1), parity 93 and ACK 94 are successively transmitted. Therefore, this communication message 96 does not have a code indicating the number of data corresponding to BC44 in one communication message 48, and F and OD are continued until there is no more data to be sent.
1"' and send, and set the EOD of the last data to 'tO"
to indicate the end of the data. However, depending on the mode, 1
The number of data that can be transmitted in one communication message is limited, and if the amount of data to be transmitted exceeds the limit, it is divided into multiple communication messages and sent.

The communication control unit 26 detects that the input/output signal line has been accessed from the switching device 1, and the DA 42 of one communication message 48
(In the case of communication message 95, slave address 86), enter the address of switching device 1 and the self address in 5A42 of communication message 48 (in case of communication message 95, master address 83). (In the case of a communication message 96, a plurality of data bits 91 are used).An identification code indicating the characteristics of the signal line on the right side of Table 1 and, if necessary, the sub-address of the own device are entered and transmitted. What is a subaddress? - When a single device, such as a CD radio frequency player, has multiple handsets with different functions, the entire device is identified by SA (or DA) and one unit is used. This is used to identify internal slave units by subaddress.

As described above, each device that detects a DC loop in one signal line by switching the multi-contact switch 10 in order receives a communication telegram 48 or 99 carrying the identification code of the accessed signal line. is sent to the switching device. This result switching device 1 can know which signal line of which device is connected to which connector of its own device. The switching device 1 stores this information in the memory section 3.

Therefore, in FIG. 1, when the information and communication system is started up by turning on the power to devices other than the video monitor 24 as described above, each device is connected to the switching device 1 in the sequence shown in FIG. 6 (1). When the communication message 48 or 96 arrives, the information from each device is stored in the memory section 3 in the format shown in FIG. In FIG. 8, the device name can be determined by looking at the SA section in the response message sent from each device, as shown in FIG. 6(1)K. (Because in this information communication system, there is a one-to-one correspondence between the device name and the address of the communication control unit).

Next, operate the switching instruction input section 11 of the switching device 1 to transfer the audio from the video disc player 22 to the audio amplifier 23.
When the communication control section 2 of the switching device 1 is set to amplify the sound, the contents of the memory section 3 (FIG. 8) are set so that the audio left output 14d of the video demesque player 22 is set to be amplified by the switching device 1.
The audio right output IE5 (1) of the video disk player 22 is connected to the connector 14 of the switching device 1, and the audio amplifier 2
3 is connected to the connector 17 of the switching device 1, and the audio input 18 of the audio amplifier 23 is connected to the connector 17 of the switching device 1.
d is connected to the connector 18 of the switching device 1, and the signal a14a and the signal it entering the switching unit 6 are
Ta, the signal line 16&, and the signal @18Δ are connected inside the switching unit 6, respectively. As a result, the left audio of the video disc player 22 can be heard from the left channel of the audio amplifier 23, and similarly the right audio of the video disc player 22 can be heard from the right channel of the audio amplifier 23.

Further, when the video monitor 24 is turned on and the switching instruction input section 6 of the switching device 1 is operated to set the video of the video disc player 22 to be viewed on the video monitor 24, the communication control section 2 of the switching device 1 is set to -memory. Examining the contents of section 3, it can be understood that the video output 12d of the video desk player 22 is connected to the connector 12 of the switching device 1, but since the information of the video input signal of the video monitor 24 is not in the memory section VC, the switching section I cannot connect by operating 6. Therefore, the multi-contact switch 10 of the DC loop forming section 6 is moved only to the "empty" (unconnected) connectors in the memory section 3, that is, the connectors 13, 16 and 19 in Table 2. Here, access is limited to connectors 13, 16, and 19 to prevent unnecessary access and the generation of impulse noise caused by superimposing DC current on the audio and video signals being played. It's for a reason.

Even if the multi-contact switch 1o is moved from the contact 2o to the contacts 13b and 16b, no response is returned because nothing is connected to the connectors 13 and 16. However, when the multi-contact switch 1o is moved to the contact 19b, the power to the video monitor 24 is turned on, so the DC current detection unit 24b detects the formation of a DC loop, and the communication control unit 24&, which receives the detection output, outputs a composite image. A communication packet containing information indicating the input is sent to the switching device 1. This sequence is the 6th
figure? ). As a result, the communication control section 2 writes the update data of the connector 19 into the memory section 3 as shown in FIG. Then, it is determined that the video input signal line of the video monitor 24 is connected to the connector 19i/im of the switching device 1.
are connected inside the switching unit 6. As a result, the video on the video disc player 22 can be viewed on the video monitor 24.

In order to simplify the explanation of the operation, FIG. 1 shows only a video disc player, an audio amplifier, a video monitor, and a switching device, but FIG. 6 shows another embodiment of the present invention incorporating a communication device.

70 is a switching device; and 71 is a network control device that connects to the public network 80 and serves to connect the single-line system to the public network outside the home. 72 is a personal computer - modem 7
3 and an A/D-D/A converter 74, 76
6 is a video disc player, 77 is a video tape recorder, and 78 is a video monitor. 79 is the home telephone. These devices (70
-79) All 26 pages have a communication control section, are connected to the information communication line 81, and can communicate with each other using communication packets 48 or 95 as shown in FIG. 3 or 4. The services possible in the information communication system of FIG. 6, which is an embodiment of the present invention, include a personal computer 72 and a modem 7.
3 and network control device 71, and further A
By using the /D-D/A converter 74, it is possible to send and receive still images and -7M synthesizer data through PC communication. /D convert,
This is possible by sending the still image from the personal computer 72 to the public network 8o via the modem 73 from the network control device 71.Receiving still images is digitally transferred from the network control device 71 to the memory of the personal computer computer 72 via the modem 73. This is possible by storing the data and displaying the forward/A converted data on the video monitor 78. Furthermore, when receiving FM synthesizer data from a public network using personal computer communication, the data is stored in the personal computer computer 72, and the A-converted data is amplified by the audio amplifier 76 to enjoy the synthesizer music. I can do it.

Effects of the Invention By configuring a terminal device such as an audio video communication device as claimed in claim 2, it is possible to detect that a DC loop is formed on the input/output signal line outside the device. A communication packet containing information indicating the characteristics of the line and an address indicating the device name of the own device can be notified to other devices via the control information communication line.

By configuring the switching device as claimed in claim 3, it is possible to form a DC loop in each signal line connected to the input/output connector connected to each audio/video communication terminal device when necessary. The content of a communication packet from a terminal device such as a communication device is compared with the connector number that formed the DC loop and stored in the memory. Based on the information stored in the memory, the audio/video communication signal is transmitted. You can make a road. By configuring the information communication system as claimed in claim 1.4, each audio
There is no need to connect the input/output signal line of the video communication device to the specified connector of the corresponding audio/video communication terminal device, just connect it freely to the input/output cover of the switchable device. It is possible to easily create an information communication system with no wiring errors.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an information communication system showing an embodiment of the present invention. FIG. 2 is a block diagram of a terminal device according to the embodiment.
3 and 4 are explanatory diagrams of communication packets used in the information communication system of the same embodiment. FIG. 5 is an explanatory diagram of the communication sequence in the information communication system of the same embodiment. A block diagram of an information communication system according to another embodiment, FIG. 7 is an explanatory diagram of a signal line identification code possessed by a terminal device according to the first embodiment of the present invention, and FIG. 8 is a memory section of a switching device according to the same embodiment. An explanatory diagram showing the correspondence between connectors and signal lines stored in FIG. 9 is an explanatory diagram of an example of connector assignment in a conventional terminal device. 1...Switching device-2, 26...Communication control section, 4゜28...Address setting section-6...
・DC loop forming part-6...Switching part-7, 27.
...Driver receiver section, 10...Multi-contact switch-21...Information communication line-26...
・DC current detection unit-48, 96...Communication packet. Name of agent: Patent attorney Shigetaka Awano and one other person

Claims (4)

[Claims] (1) Input audio and/or video signals and/or
or a plurality of terminal devices for outputting, a control information communication line connected to each of the terminal devices for sending control information about the terminal devices, and an audio/video signal line for sending audio signals and/or video signals; In an information communication system having a switching device that performs signal switching to send audio/video signals from one terminal device to any other terminal device via the audio/video signal line, the terminal device itself A DC current detection unit that detects that DC current has flowed through the audio/video signal line of the device via the switching device; and a communication control unit having a function of generating and transmitting a communication message containing information indicating the characteristics of the audio/video signal line,
The switching device includes a switching unit that forms a transmission path for audio signals and/or video signals between terminal devices, and a direct current path that provides a current path for flowing a DC current through any audio/video signal line that enters the switching unit. An information communication system comprising a loop forming section and a communication control section that communicates with another terminal device via a control information communication line and controls the switching section and the DC loop forming section. (2) A DC current detection unit that detects when a DC current flows through the own audio/video signal line via a switching device, and receives the output of this DC current detection unit to determine the identification code of the own terminal device and the DC current. 1. A terminal device comprising: a communication control unit having a function of generating and transmitting a communication message including information indicating characteristics of an audio/video signal line through which current flows. (3) Formation of a DC loop that includes a switching unit that forms a transmission path for audio and/or video signals between terminal devices, and a current path for flowing DC current through any audio/video signal line that enters the switching unit. and a communication control section that communicates with the other terminal device via a control information communication line and controls the switching section and the DC loop forming section. (4) In claim (1), the switching device further includes a memory section for storing identification codes of terminal devices connected to the switching device and characteristics of audio/video signal lines, and terminals not stored in the memory section. When there is a request to connect the audio/video signal line of the device, the DC loop forming section is controlled to apply DC current to the audio/video signal line of the switching device to which the terminal device was not connected and connect the new terminal. An information communication system characterized in that the contents of the memory section are updated by a communication message sent from the device.