JPH01129695A - Key telephone system - Google Patents

Abstract

PURPOSE:To reduce the total number of transmission burst signals by sending/ receiving a voice data between master and slave main systems while being collected by plural frames together. CONSTITUTION:A time switch 5a of a master set 1a, in the event of sending a voice data, reads a voice data by each frame from a time slot designated by a voice highway 6a, stores plural frames of data in a storage circuit 4a once and gives one selection address and sends them in the lump. Slave sets 1b-1n receive and identify a selection address and receive the voice data by plural frames in the lump and store them in storage circuits 4b-4n and sends them for one frame each to voice highways 6b-6n.

Description

[Detailed Description of the Invention] [Object of the Invention] (Field of Industrial Application) The present invention provides a button telephone device in which a plurality of slave button telephone main devices are multi-point connected to one master button telephone main device. Regarding.

(Prior art) In recent years, a method has been proposed in which multi-point connections are made between multiple digital button telephone main devices in order to achieve functions such as inter-extension calls, central office line transfers, and broadcast communications between the main devices. has been done. Features of this system include ease of wiring work and simultaneous calling. The data sent and received between the main devices using this method includes audio data and control data such as selection signals. Each main device is equipped with a microprocessor having a serial transmission interface section in each main device connection interface unit.

FIG. 3 shows a block configuration of a key telephone device based on this method.

One master main device 11a and a plurality of slave main devices 11b to 1,1. n, the processor in the master main device 11a is in master mode,
slave main device], 1. The processors in b~1,1n are set to slave mode.

Since the audio β1 data has a faster bit rate than the control data, conventionally it has not been possible to use a microprocessor to send and receive audio data, but recently microprocessors have become faster and this has become possible. in this case,
In order to send and receive 8-bit audio data during one frame (125 microseconds), audio data is sent from the master mode processor to the slave mode processor following the selected address that specifies the slave mode processor. method is adopted.

Conventionally, this method allows two systems to be connected to one intersystem highway.
When loading audio data for channels (64Kbit x 2 channels), as shown in Figure 4, the master mode processor sends the selected address B1 to the first audio channel B1.
, selected address B1 and audio second channel B2 within one frame. In this case, for the transmission of control data, for example, 3 bits of the 8 bits of the address burst are used for the selected address (in other words, there are a maximum of 8 slave processors), and the remaining 5 bits are used for transmitting the control data. There is. Control data is not always present in every frame, but voice data is present in every frame once a call has begun. A start-stop transmission method is used for communication between processors, and one burst consists of 11 bits, including 1 start bit, 1 address/data select bit, 8 data bits, and 1 stop bit. There is.

When audio data is transmitted in this manner, four bursts, or a total of 44 bits, and a total of 8 bits as guard time between each burst are required within one frame on the intersystem connection highway. Therefore, if one frame is 125 μsec, the bit rate on the intersystem connection highway is 416 Kbps, which requires a very high speed intersystem connection highway and processor.

(Problems to be Solved by the Invention) As mentioned above, in the conventional device, the processor processes the data of 64 Kbps per channel sent from the audio highway in the master main device frame by frame, and selects the selected address and controls. Since data and voice data are being sent over the intersystem interconnection highway, a high speed intersystem interconnection highway and a processor capable of high speed processing are required.

SUMMARY OF THE INVENTION An object of the present invention is to provide a button telephone device that is capable of transmitting and receiving high-speed voice data at 64 Kbps per frame using current processors that do not have very high processing power, and that is formed by connecting multiple processors at multiple points. .

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a system in which one of a plurality of key telephone main devices each having a serial transmission interface section is a master main device, the others are slave main devices, and one master main device is used. In a button telephone device in which a plurality of slave main devices are multi-point connected via the respective serial transmission interface sections to enable transmission and reception of voice data between the master and slave main devices, the master main device is means for storing a plurality of frames of audio data received frame by frame from the audio highway in the device; and a means for attaching one selection address to the plurality of frames of audio data in the storage means to connect the serial transmission interface unit to the serial transmission interface unit. and means for transmitting the audio data to the slave main device via the serial transmission interface unit, and each slave main device receives and identifies the selected address, and then receives and stores the plurality of frames worth of audio data from the serial transmission interface unit. The present invention provides a button telephone device characterized by having means for transmitting a plurality of frames of voice data in the storage means to a voice highway in the autonomous device frame by frame.

(Function) In the above configuration, when transmitting audio data, the master main device reads the audio data frame by frame from the audio highway, first stores the audio data for multiple frames in the storage means, and then transmits the audio data for the multiple frames. 1 audio data to this
Send in bulk with one selected address. After receiving and identifying the selected address from the master main device, the slave main device collectively receives multiple frames of audio data that are subsequently sent, stores it in the storage means, and then outputs one frame of audio data. It is sent to the audio highway every time.

In this way, by transmitting and receiving multiple frames of audio data all at once, the master main unit only needs to attach one selection address to multiple frames of audio data, reducing the total number of bursts to be transmitted. and does not require as fast intersystem connection highways and processors.

(Example) Examples will be explained below.

FIG. 1 is a block diagram showing the configuration of an embodiment of a key telephone device according to the present invention.

There is one master main device 1a, and a plurality of slave main devices 1b to 1n connected to it at multiple points via a downlink and uplink intersystem connection highway 12.1.3. Since each main device 1a to 1n has the same configuration,
Taking the master main device 1a as an example, its configuration will be explained below.

The main device 1a has an intersystem connection processor (hereinafter simply referred to as a processor) 2a that transmits and receives data to and from an intersystem connection processor of another main device, and an arbitrary processor on the audio highway 6a under the control of this processor 2a. It also includes a time switch 5a for reading or writing audio data from the time slot. The processor 2a is provided with a serial interface section 3a for performing serial transmission with other processors, and a storage circuit 4a for storing data for a plurality of frames. In addition,
Other known components that each main device should normally include will not be illustrated or described here.

The time switch 5a reads audio data (8 bits) every frame from a designated time slot of the audio highway 6a. The processor 2a temporarily stores this audio data in the storage circuit 4a, repeats this operation multiple times, and then transmits the stored multiple frames of audio data all at once to the processor at the destination of the call via the serial interface section 3a.

Here, the processor 2a of the master main device 1a is set to master mode, and those of slave main devices 1b to 1n are set to slave mode (hereinafter referred to as master processor 2a and slave processors 2b to 2n, respectively).

FIG. 2 shows the format of data transmitted from the master processor 2a to the slave processors 2b to 2n. FIG. 2 shows an example of a system in which two frames of audio data are stored in the storage circuit 4a and two frames of audio data are transmitted to the intersystem connection highway 12.

The storage circuit 4a of the master processor 2a has a capacity sufficient to store two frames worth of audio data. The master processor 2a temporarily stores two frames worth of audio data received via the time switch 5a in synchronization with the frame synchronization signal of the audio highway 6a in the storage circuit 4a. A timer circuit (
(not shown) starts transmitting serial data. In order to transmit data for two frames at once, the selection address for specifying the destination slave processors 2b to 2n is 1 before the audio data for two frames.
You only need to send it once.

That is, after transmitting the selected address A, two frames worth of audio data B11 (first frame data of the first channel),
B12 (The 27th frame data of the first channel is transmitted in order. The contents and bit structure of each burst are the same as those of the conventional one.

When controlling data for two audio channels per processor, after transmitting the audio data B12, select address A1 audio data B21 (first channel of the second channel).
bursts of frame data) and B22 (second frame data of the second channel) are sequentially transmitted.

The slave processors 2b to 2n on the reception side receive and identify the selection address, and if the own device is selected as a result, perform the operation opposite to the above.

That is, after receiving the audio data for two frames following the selected address via the inter-system connection highway 12 and storing it in the storage circuits 4b to 4n, frame synchronization of the respective audio highways 6b to 6n is performed. In synchronization with the signal, the audio data in the storage circuits 4b to 40 is transferred frame by frame to the audio highway 6b via the time switches 5b to 5n.
~6n to the specified time slot.

In this way, by transmitting two frames worth of audio data at once, the selection address can be transmitted only once every two frames per audio channel, reducing the total number of transmission bursts and reducing the burden on the serial interface section. It is possible to reduce the number of pit-rays and the processing load on the processor. Furthermore, it is naturally possible to transmit three or more frames at once, and in that case, the total number of transmission bursts is further reduced.

〔Effect of the invention〕

As explained above, according to the present invention, audio data is sent and received between the master and slave main devices in units of multiple frames, so when the master main device transmits audio data, it is divided into multiple frames of audio data. Since only one selection address is required and the total number of transmission bursts can be reduced, the effect is that high-speed voice data can be transmitted and received even when using the current inter-system connection highways and processors that are not very high-speed. It will be done.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of a button telephone device according to the present invention, FIG. 2 is a format diagram of transmission data in the embodiment of FIG. 1, and FIG. 3 is a block diagram of a conventional button telephone device. , FIG. 4 is a format diagram of transmission data in a conventional device. 1a...Master main device, 1b-I n slave main device, 2a...Master processor, 2b-2n...
Slave processor, 3a to 3n... Serial interface section, 4a to 4n... Memory circuit, 5a to 5n.
...Time switch, 6a-6n...Voice highway. Applicant's agent Mr. Sato

Claims (1)

[Claims] Among a plurality of key telephone main devices each having a serial transmission interface unit, one is a master main device and the others are slave main devices, and a plurality of slave main devices are connected to one master main device by each of the serial transmission interfaces. In a button telephone device that enables transmission and reception of voice data between a master and slave main devices by multi-point connection via a main device, the master main device transmits multiple frames received frame by frame from a voice highway in the independent device. and means for attaching one selection address to a plurality of frames of audio data in the storage means and transmitting the same to the slave main device via the serial transmission interface unit. , each of the slave main devices receives and identifies the selected address, and then receives and stores the plurality of frames worth of audio data from the serial transmission interface section, and the plurality of frames worth of audio data in the storage means. A button telephone device characterized in that it has means for transmitting a frame by frame to a voice highway within the autonomous device.