JPH0398396A - Multiplex system for key telephone master set - Google Patents

Abstract

PURPOSE:To reduce the number of digital subscriber lines to be connected to a private branch exchange by multiplexing and sending communication information of plural key telephone sets accommodated in a key telephone master set. CONSTITUTION:The above multiplex system consists of a key telephone set 1 and a key telephone master set comprising a subscriber circuit 5 accommodating the key telephone set 1, a control bus 6 connecting control information of the subscriber circuit 5 to a central processing unit 7, a code conversion circuit 8 converting speech information of the subscriber circuit 5, a multiplexing circuit 9 multiplexing the coded speech information and a central processing unit 7 controlling the multiplexing circuit 9 with the control information of the subscriber circuit 5. Moreover, a private branch exchange 4 comprising a subscriber circuit 12 receiving a multiplexed output of the key telephone master set, a demultiplex circuit 13 demultiplexing the received multiplexing signal, a time division switch 15 and a central processing unit 14 and a digital subscriber line 3 are provided. Thus, the number of the subscriber lines 3 to be connected to the private branch of exchange 4 is reduced by the multiplexing and transmitting the signal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a private branch exchange accommodating a key telephone main device, and more particularly to a multiplexing system for a key telephone main device and a private branch exchange.

[Conventional technology]

Conventionally, as a connection method between this type of key telephone main device and a private branch exchange, a space division switch has been used to connect each line of the key telephone and the analog subscriber circuit of the exchange. Therefore, in the key telephone main unit, each "I" line of the key telephone is connected using a space division switch, and analog connection of the private branch exchange is performed. It was outputting to the 8th floor. Therefore, Button ZI episode 2. 1-. Multiple pairs of telephone cables were required between the equipment and the private branch exchange. FIG. 3 is a block diagram showing the connection between a conventional key telephone main unit and a private branch exchange.

In the button telephone main unit 22, a space division switch is activated by a line selection button signal from the button telephone 21, and the button telephone having a call request is connected to one of the subscriber lines 23. Particularly when the key telephone main device is electronic, such as using a microcomputer control method, the line selection button signal from the key telephone 21 is input to the subscriber circuit 25 of the key telephone main device 22, and this input information is used for control. It is sent to the central processing unit 27 via the bus 26. Central processing unit 27 generates a switching signal for switching space division switch 28, which connects key telephone 21 via subscriber line 23 to two analog subscriber circuits of private branch exchange 24.

[Problem to be solved by the invention]

The conventional connection method between the key telephone main unit and the private branch exchange described above uses an analog subscriber line to connect the key telephone main unit and the private branch exchange, which requires a considerable amount of subscriber lines even when traffic is taken into consideration. And so. Therefore, there is a drawback that the cost of laying the subscriber line cable as well as the cost of installing the subscriber line is large.

An object of the present invention is to provide a button telephone main device that can reduce the amount of digital subscriber lines connected to a private branch exchange by multiplexing and transmitting the communication information of a plurality of key telephones accommodated in the key telephone main device. The objective is to provide a multiplexing method.

[Means to solve the problem]

The multiplexing method of the button telephone main device of the present invention includes a plurality of subscriber circuits accommodating button telephones, a code conversion circuit that encodes the output information of the subscriber circuit, and a code conversion circuit that encodes the output information of the code conversion circuit. A button telephone main device comprising a multiplexing circuit for multiplexing information, a central processing circuit for connecting caller information of the subscriber circuit via a control bus and controlling the multiplexing circuit, and a central processing circuit for controlling the multiplexing circuit; a subscriber circuit that receives the multiplexed signal output from the key telephone main device, a separation circuit that separates the received multiplexed signal, and is controlled by the separation circuit;
The private branch exchange includes a central processing circuit that generates a time division switch control signal, and a time division switch that switches and connects call information output from the multiplexing circuit under the control of the central processing unit.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. FIG. 1 shows a button telephone 1, a subscriber circuit 5 accommodating the button telephone 1, a control bus 6 that connects control information of the subscriber circuit 5 to a central processing unit 7, and a code for communicating call information of the subscriber circuit 5. A key telephone main device 2 having a code conversion circuit 8 for converting code, a multiplexing circuit 9 for multiplexing encoded call information, and a central processing unit 7 for controlling the multiplexing circuit 9 using control information from a subscriber circuit 5. , a subscriber circuit 12 that receives the output of the multiplexed key telephone main device, a separation circuit 13 that separates the received multiplexed signal, and a time division switch 15.
A private branch exchange 4 having a central processing unit 14 and a digital subscriber line 3 receive an e-mail.

When a call request is received from the button telephone 1, the subscriber circuit 5 of the key telephone main unit separates the call information into control alerts and call information, and the call information is code-converted by an encoding circuit 8 and multiplexed. Output to 9. On the other hand, control information is input to the central processing unit 7 via the bus line 6, and the multiplexing circuit 9 is controlled by a multiplexing control signal generated based on this control information. Subscriber circuit] 2. The multiplexed output signal of the key telephone main unit received by the subscriber circuit 12 is divided into call information and control information for each key telephone by the minute M circuit 13, and the call information is sent to the time division switch 15, and the control information is sent to the central processing unit. Each is connected to the device 14. The call notifications connected to the time division switch are connected and exchanged to the desired destination by control signals from the central processing unit 14.

FIG. 2 is an elliptic diagram showing one embodiment of a data signal used in the present invention. This signal structure is, for example, 64Kbp
s frame synchronization pattern, a 64 Kbps control signal channel, and a 64 Kbps information signal channel.

- 5 6 [Effects of the Invention] As explained above, the present invention enables a key telephone main device to multiplex and transmit communication information of a plurality of key telephones accommodated in the key telephone main device, thereby making it possible to transmit communication information to a treetop switch. It is possible to reduce the amount of circuits of the four subscriber lines that are connected to the subscriber, and therefore it is possible to reduce cable costs and installation costs.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a data signal configuration diagram of an embodiment of the present invention, and FIG. 3 is a conventional diagram. FIG. 2 is a block diagram showing the connection between a key telephone main unit and a private branch exchange. 1.21...Button telephone, 2.22...Button telephone main unit, 3...Digital subscription - Meishinsen, 4.24.
・Private branch exchange, 5.25...Subscriber circuit of key telephone main device, 6.26...Control bus, 7, 27...Central processing unit of key telephone main device, 8...Encoding circuit ,9
...Multiplex circuit, 12...Digital subscriber circuit of private branch exchange, 13... Separation circuit, l4...Central processing unit of private branch exchange,]5...Space division switch of private branch exchange, 23...Analog subscriber line, 28...Space division switch of key telephone main unit, 29. ... Ana I Cog Kanto of the Magauchi Switchboard - Otonodoro,,

Claims (1)

[Claims] In a multiplexing method for key telephone main devices in a private branch exchange that connects a plurality of key telephone main devices via transmission lines, a plurality of subscriber circuits accommodating the key telephone devices and the output information of the subscriber circuits are encoded. A first circuit that connects a code conversion circuit, a multiplexing circuit that multiplexes coded information outputted by the code conversion circuit, and calling party information of the subscriber circuit by a control bus, and controls the multiplexing circuit. a key telephone main device comprising a central processing circuit; a subscriber circuit that receives multiplexed signals output from the key telephone main device via a transmission line; a separation circuit that separates the received multiplexed signal; a second central processing circuit that generates a time division switch control signal under the control of the circuit; and a time division switch that switches and connects the call information output by the multiplexing circuit under the control of the second central processing unit. A multiplexing system for key telephone main equipment, characterized by having a private branch exchange.