JPS6387063A - Automatic recalling system for digital exchange system - Google Patents

Abstract

PURPOSE:To ensure the effective communication of data with a trunk line by allocating a dead MODEM if secured in a pooled MODEM to a multi- function telephone set which is operating an automatic call key. CONSTITUTION:A data communication key 13 is depressed while a multi-function telephone 2 is busy with a trunk line. Under such a condition, an exchange 1 holds the trunk line and sends a busy tone back to the telephone 2 if a pooled MODEM 9 has no dead area. If an automatic recall key 14 is depressed under such a condition, the exchange 1 writes '01' to the corresponding area of an automatic recall flag table. When the MODEM 9 is idle under such a condition, the exchange 1 sets the corresponding flag of a table 100 at '00' to reserve the corresponding MODEM and performs an automatic recall to the telephone 2. When the telephone 2 answers the recall, the exchange 1 connects the reserved MODEM to the telephone 2 to attain the communication of data via a data terminal 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to an automatic call return method for a pooled modem digital switching system.

(Conventional technology) With the recent progress in office automation, digital exchanges are now being configured to connect not only voice terminals such as multi-function telephones, but also various data terminals to communicate both voice and data. A digital exchange system has been developed.

FIG. 4 is a block diagram showing the conventional configuration of this type of digital switching system. The digital switching system 1 includes a multifunction telephone (hereinafter abbreviated as EKT) as a voice terminal and a digital interface unit for data communication.
An EKT/DIU unit 2 that integrates an EKT/DIU unit (abbreviated as DIU) is connected to a data control unit 3 that includes an EKT interface unit and a DILI interface unit of the digital exchange 1, and a central office line network 5 is connected to a central office line network 5. line interface unit 6, modem 7 and digital interface unit (hereinafter referred to as DI).
Pooled modems 9 consisting of U) 8 are each connected to a modem pooling unit 10.

The DIU (not shown) in the E KT/DI U unit 2 has a function as an adapter for connecting the data terminal 11 to the digital exchange 1, and when connecting n data terminals 11, n EKT/DIU units 2 are also connected corresponding to each data terminal. All operations necessary for data communication are performed using EKT dial keys and function keys corresponding to each data terminal.

FIG. 5 is a flowchart showing the operation when transmitting a central office line for the purpose of data communication, and the digital exchange I11 is
When the KT detects that an off-hook operation or an operation of function key <DN key) 12 equivalent to off-hook has been performed (step 20), after performing extension connection processing,
A dial tone signal is returned to the EKT as a response signal (step 21). Here, when the EKT operator confirms the dial tone and sends the central office line dial number, exchange t11 performs connection processing with the corresponding central office line, and if the central office line responds, it enters the communication state (step 22
~23). After this, in order to switch to data communication, EKT
When the data terminal 11 is pressed, it is checked whether the pooled modem 9 is idle, and if it is idle, the data terminal 11 A data communication path is formed between the terminal and the central office line 12 (steps 24 to 26). Next, the voice communication path with the EKT is released and a data communication state is established (step 2).
7-28).

However, if the pooled modem 9 is being used by another data terminal and is not available, the central office line side is put on hold and an EKT heavy tone is returned (step 29). Therefore, data communication cannot be performed until the pooled modem 9 returns to the idle state, but in this state, the exchange l11
When the KT detects that the DN key 12 has been operated (step 30), the EKT is returned to the communication state with the central office line until the pooled modem 9 becomes idle.

However, if the DN key is not operated and the call end key RLS or the data communication end key DR8 provided on the EKT is operated (step 31), the voice communication path between the EKT and the exchange 1 is released; End the conversation (step 32)
~33).

In this way, data terminals 11 and II! A pooled modem 9 connected to a digital exchange 1 for data communication with 5
of? ! This is done by sharing data among several data terminals.

(Problem to be Solved by the Invention) However, in the conventional system described above, in order to perform data communication again when the pooled modem 9 is full, it is necessary to press the DN key 12 to return to the call. , call until a pooled modem becomes available, or press RLS key or DR
There are only two ways to do this: press the S key to end the call, and then call station M again.

Therefore, even if a pooled modem becomes available, data communication is not always possible immediately, and there is a problem in that central line transmission for the purpose of data communication cannot be performed efficiently.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic call return system for a digital switching system that can efficiently make a central line call when a pooled modem becomes available.

[Structure 1 of the Invention: Means for Solving the Problems] The present invention provides a device that integrates a digital interface unit and a multifunctional telephone when a group of modems, all of which are in use, becomes vacant. An automatic callback key is provided to reserve a vacant modem and instruct an automatic callback to be generated from the digital exchange. Allocating a vacant modem to the device on which the automatic call return key is being operated when the automatic call return occurs, performing automatic call return, and forming a data communication path between the central office line and the data terminal in response to the automatic call return; It is designed to start data communication.

[Operation] When a pooled modem becomes vacant, the vacant modem calls the device (EKT/DII) that operates the automatic call key.
J) is assigned for data communication, and an automatic call return is issued to the device in question. When the corresponding device responds to this, a data communication path is established using a vacant modem.

Therefore, by operating the automatic call-back key, you can make a call until the pooled modem is free, or make a call to the central office line again. become possible.

(Embodiment) Fig. 1 is a block diagram showing an embodiment of the present invention, and the difference from the conventional configuration shown in Fig. 4 is the EKT/DIU2 EK.
An automatic call return key 14 is installed in the T, and an EKT/DIU is installed inside the digital exchange 1!1 as shown in FIG.
An automatic call-back flag table 100 is provided which stores one-byte automatic call-back flags (set-01, reset=00) corresponding to each of the two dial numbers.

FIGS. 3(a) and 3(b) are flowcharts showing the process by which the digital exchange 1 performs automatic call return. First, when the EKT of the EKT/DIU 2 is talking to the central office line (
Even if the DIU key 13 is pressed in step 3-1) (
Step 3-3> If there is no free space in the pooled modem 9, the central office line is held and an EKT heavy tone is returned (3
-12). When the automatic callback key 14 is pressed at this time (step 3-13), the exchange 1a1 writes "ol" in the dial number corresponding area of the corresponding DIU in the automatic callback flag table 100 (step 3-14). After this,
When the RLS key or DRS key is pressed (step 3-16), the automatic call return flag is cleared to "00" (step 3-17), the voice path is released (step 3-18), and the call is ended. When the DN key 12 of the EKT (step 3-19) is pressed (step 3-15), the process returns to the telephone conversation with the central office line (step 3-1). In this state,
Since "01" is written in the automatic call-back flag, check the idle state of the pooled modem 9 after checking the conditions in (Step 3-2) (Step 3-4>).
If there is a free modem available at any time, reserve one free modem (Step 3-5>) and clear the automatic call return flag to "00" (Step 3-6).
Automatic callback to L12 DIU (step 3-7)
. In response to this callback, the corresponding E KT/D IU E
When the KT responds by pressing the DItJ key 13 (step 3-8), the exchange t11 creates a data bus via the reserved free modem (step 3-9) u, and releases the audio path (step 3). -10), and data communication with the central office line is in progress (step 3-11).

In this way, by operating the automatic callback key 14 in the EKT/DIU2, simply by responding to the automatic callback from the exchange eii, the EKT/DIU2 can reliably and immediately call back through an idle modem when it becomes available. data communication with the central office line.

[Effects of the Invention] As explained above, according to the present invention, simply by responding to an automatic call return from the exchange, data can be reliably communicated with the central office line via an idle modem, and immediately when an idle modem becomes available. Since communication can be performed, it is possible to eliminate the wasteful effort of repeating calls over and over again to the central office line, and efficient data communication becomes possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing an automatic call back flag table that stores flags for performing automatic call back, and FIGS. 3 (a) and (b) are FIG. 4 is a block diagram of a conventional digital switching system, and FIG. 5 is a flowchart showing the processing of a conventional digital switching system when calling a central office line. 1...Digital exchange, 2...EKT/DIU. 3... Data control unit, 5... Office line network, 6... Office line interface unit, 7... Modem group, 8... DIU, 9... Pooled modem, 1
o...Modem pooling unit, 11...Data terminal, 14...Automatic call return key. Figure 3 (0) Figure 5

Claims (1)

[Scope of Claims] A pooled modem in which a group of modems connected to a digital exchange is shared by a plurality of data terminals, and data communication is performed between the data terminals connected to the digital exchange and a central office line via a digital interface unit. In this type of digital switching system, when a vacant modem becomes available in a group of modems that are all in use in a device that integrates the digital interface unit and a multi-function telephone, the vacant modem is reserved. A device that is provided with an automatic call back key that instructs a digital exchange to generate an automatic call back, and that the digital exchange operates the automatic call back key when a vacant group of modems becomes available, all of which are in use. A digital switching system characterized in that it allocates a vacant modem to a user, automatically returns the call, and in response, forms a data communication path between the central office line and the data terminal, and starts data communication. Automatic callback method.