JPS598462A - Mutual communication system of party line telephone - Google Patents

Mutual communication system of party line telephone

Info

Publication number
JPS598462A
JPS598462A JP57116671A JP11667182A JPS598462A JP S598462 A JPS598462 A JP S598462A JP 57116671 A JP57116671 A JP 57116671A JP 11667182 A JP11667182 A JP 11667182A JP S598462 A JPS598462 A JP S598462A
Authority
JP
Japan
Prior art keywords
circuit
wire
subscriber
voice
current supply
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP57116671A
Other languages
Japanese (ja)
Other versions
JPH0359633B2 (en
Inventor
Haruyuki Yoshino
吉野 春幸
Hideo Tatsuno
秀雄 龍野
Shigeru Hozumi
穂積 茂
Koichi Hasegawa
浩一 長谷川
Kaneichi Otsuki
大槻 兼市
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Ltd
Hitachi Ltd
NEC Corp
Nippon Telegraph and Telephone Corp
Oki Electric Industry Co Ltd
Original Assignee
Fujitsu Ltd
Hitachi Ltd
NEC Corp
Nippon Telegraph and Telephone Corp
Oki Electric Industry Co Ltd
Nippon Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd, Hitachi Ltd, NEC Corp, Nippon Telegraph and Telephone Corp, Oki Electric Industry Co Ltd, Nippon Electric Co Ltd filed Critical Fujitsu Ltd
Priority to JP57116671A priority Critical patent/JPS598462A/en
Publication of JPS598462A publication Critical patent/JPS598462A/en
Publication of JPH0359633B2 publication Critical patent/JPH0359633B2/ja
Granted legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q5/00Selecting arrangements wherein two or more subscriber stations are connected by the same line to the exchange

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Devices For Supply Of Signal Current (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

PURPOSE:To attain the communication without lowing a voice level, by bringing a channel current supply section to high impedance, and terminating in matching at a 2/4-wire converting section. CONSTITUTION:When a specific number from a telephone set 1 is detected 12- 17, a control circuit controls switches 6-9 to transmit a ringing signal of interphone 26 and to attain mutual calling between A and B telephone sets 1, 2. Further, switches 20, 21 for connection and disconnection of a 2/4-wire converting circuit 18 are controlled for opening to bring an impedance in terms of a voice frequency viewed from the telephone sets 1, 2 to a subscriber circuit 25 into a high level state. As a result, a call current is applied to the telephone sets 1, 2 from the subscriber circuit 25 and the subscriber circuit 25 to the voice is made to non-connecting state, allowing to prevent the decrease in the voice level.

Description

【発明の詳細な説明】 (1)発明の技術分野 本発明は共同電話機とインタフェースする加入者回路に
係り、特にディジタル交換機用加入者回路において共同
電話機間での相互通話?高品質にて可能とした共同電話
機の相互通話方式%式% (2)技術の背景 現在、局用の電話交換装置では通話使用頻度の少ない加
入者を対象にして共同電話機が広く利用式れている。共
同電話機の制約粂件としては、共同電話機加入者のうち
1人が使用している期間、他の加入者は電話全利用する
ことができないものである。一方交換機の技術発展は最
近空間分割形交換機から時分割交換機へと移行しつつあ
る。そして時分割交換機においても共同電話機全収容す
る必要があり、時分割交換機特有の接続手段上考慮した
有効なる実現手段が要望されている。
DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a subscriber circuit that interfaces with a public telephone set, and in particular to a subscriber circuit for a digital exchange that allows mutual communication between public telephone sets. High-quality interactive telephone communication system made possible by % type% (2) Background of the technology Currently, communal telephones are widely used in central office telephone exchanges for subscribers who rarely use telephone calls. There is. One of the limitations of communal telephones is that while one of the communal telephone subscribers is using the telephone, other subscribers cannot make full use of the telephone. On the other hand, the technological development of switching equipment has recently been shifting from space-division switching to time-division switching. It is also necessary to accommodate all communal telephones in a time-division exchange, and there is a need for an effective means of implementation that takes into consideration connection means specific to time-division exchanges.

(3)  従来技術と問題点 従来の空間分割交換機における共同電話機間での相互通
話方式ケ第1図によって説明する。
(3) Prior art and problems The mutual communication system between communal telephones in a conventional space division switch will be explained with reference to FIG.

第1図において、1.2は共同電話機、1.を空間分割
スイッチ、4は発信レジスタトランク(ORTI、51
d呼出し信号トランク會示す。
In FIG. 1, 1.2 is a public telephone; space division switch, 4 is the outgoing register trunk (ORTI, 51
d paging signal trunk meeting.

いま第1図(a)[て、甲加入者1が乙加入者2との間
での相互通話全要望し、特番”112”ji:ダイヤル
発信すると、発信レジスタトランク(ORT 14はネ
ットワーク(NW )3軽由でこれを受信し、制御系(
図示せず)K、通知する。制御系からの指令により発信
レジスタトランク(ORT14は呼出し18号トランク
(RGT15へと接続が切換る。呼出し信号トランク(
RGTI5は甲加入者1及び乙加入者2に対する60イ
ンターの吐出信号を実行するとともに乙加入者2が応答
することを検出し、リングトリップする。甲と乙の通話
期間中、呼出し信号トランクfRGT15は甲と乙の通
話状態全監視しており、ネットワークは甲と乙と呼出し
信号トランク(RGT15との選択経路を閉成した状態
のit保持する。
Now, as shown in Fig. 1(a), when subscriber 1 requests a mutual call between subscriber 2 and subscriber 2, and dials the special number "112", the outgoing register trunk (ORT 14 is connected to the network ) 3, the control system (
(not shown) K, notify. In response to a command from the control system, the connection of the originating register trunk (ORT 14 is switched to the calling trunk No. 18 (RGT 15). The calling signal trunk (
The RGTI 5 executes a 60-inter discharge signal to the A subscriber 1 and the B subscriber 2, detects that the B subscriber 2 responds, and performs a ring trip. During the call period between Party A and Party B, the call signal trunk fRGT15 monitors the entire call status between Party A and Party B, and the network maintains it in a state where the selected route between Party A and Party B and the call signal trunk (RGT 15) is closed.

甲加入者lあるいは乙加入者2が特に図示しない第三者
と変換機孕介して通話する場合においては第3のトラン
クを使用することになる。ここで、0RT4及びRGT
5は音声周波数に対しハイインピーダンス終端であり、
第3のトランクは整合終端となっている。このように、
SD交換機においては専用機能金有する複数種類のトラ
ンク回路會所望のタイミングに所望のトランクを接続替
えすることで実施するために、相互通話時は音声周波数
に対しハイ・インピーダンス化することが容易であった
。一方、TD交換機において1−1BOR8CHT機能
(B;バッテリ、O;オーバポルチー?プロテクシ目ン
、R加入者関連機能を一種類の加入者回路上で実現して
いるため通話電流供給等?実施するBSCH機能部は常
時音声に対し整合終端となっている。従って、相互通話
時はレベル低下上期たしてし才う状態にあった。
When subscriber 1 or subscriber 2 communicates with a third party (not shown) through a converter, the third trunk is used. Here, 0RT4 and RGT
5 is a high impedance termination for audio frequencies,
The third trunk has a matched termination. in this way,
In SD exchanges, multiple types of trunk circuits each having a dedicated function are implemented by connecting and switching desired trunks at desired timings, so it is easy to set high impedance to voice frequencies during mutual calls. Ta. On the other hand, in a TD exchange, the 1-1BOR8CHT functions (B: battery, O: over-polarity protection, R subscriber-related functions are realized on one type of subscriber circuit, so call current supply, etc.) are implemented using BSCH. The functional section always has a matched termination for voice.Therefore, during mutual communication, the level would drop for a while.

(4)発明の目的 本発明は常時音声周波数に対し整合終端している加入者
回路會共同電話機間での相互通話時は音声周波数に対し
て?・イ・インピーダンス終端することにより共同電話
機間での相互通話を可能ならしめる共同電話機の相互通
話方式を提供すること全目的とするものである。
(4) Purpose of the Invention The present invention provides matching termination for voice frequencies at all times during mutual communication between subscriber circuit community telephones. - The overall purpose of this invention is to provide an intercommunication system for communal telephones that enables mutual communications between communal telephones by impedance termination.

(5)観測の構成 そしてこの目的は本発明によれば、通話電流供給回路及
び2線4線変換回路を具備するディジタル交換機用の加
入者回路において、前記通話電流供給回路全音声周波数
に対しハイ・インピーダンス終端となし、前記2線4線
変換回路を音声周波数に対し整合終端となし、該通話電
流供給回路と該2線4線変換回路全′屯気的に並列接続
する接点全具備し、共同電話機間の相互通話時には制御
回路の第1の指令により該接点を駆動して該2線4線変
換回路會切離し、加入者回路を音声周波数に対してハイ
−インピーダンス終端となし、共同電話機間の相互通話
全要望には制御回路の第2の指令により該通話電流供給
回路と該2線4線変換回路會′亀気的に並列接続するよ
うに該接点?駆動し、加入者回路全音声周波数に対して
整合終端させることを特徴とする共同電話機の相互通話
方式を提供することによって達成される〇 (6)発明の実施例 以下本発明実施例全図面によって詳述する。
(5) Observation structure and purpose of this invention is to provide a subscriber circuit for a digital exchange equipped with a speech current supply circuit and a 2-wire 4-wire conversion circuit, in which the speech current supply circuit has a high frequency response for all voice frequencies.・The 2-wire 4-wire conversion circuit has an impedance termination, the 2-wire 4-wire conversion circuit has a matched termination for the audio frequency, and all contacts are provided for electrically connecting the communication current supply circuit and the 2-wire 4-wire conversion circuit in parallel; During mutual communication between communal telephones, the contact is driven by the first command of the control circuit to disconnect the 2-wire and 4-wire conversion circuit, and the subscriber circuit is made into a high-impedance termination for the voice frequency, and between the communal telephones. For all requests for mutual communication, the second command of the control circuit causes the communication current supply circuit and the 2-wire 4-wire conversion circuit to be electrically connected in parallel to the contacts? 〇(6) Embodiments of the Invention The following embodiments of the present invention are shown in all the drawings. Explain in detail.

第2図にTD父換機において共同電話機とインタフェー
スする加入者回路のブロック構成上水す。加入者回路2
5は複数種類の加入者関連機能を具備しているが、ここ
では共同電話機とインタフェースするために特に必要と
する機能に絞って記述しである。給電回路16は1組の
コンプリメンタリなトランジスタ12.13と抵抗14
.15と一体となり、電話機1,2に対する通話電流の
供給及び加入者監視(ダイヤルパルス受信も含む)全実
行する。2線4線変換回路18#−1音声周波数に対し
て整合終端しており、電話機1又は2と1,2以外の第
3の電話機との間での通話?可能ならしめる機能?具備
している。PCM符号・復号器19は2線4線変換回路
18との間でのアナログ・ディジタル変換?実行する。
FIG. 2 shows the block configuration of the subscriber circuit that interfaces with the public telephone set in the TD main switch. Subscriber circuit 2
5 has multiple types of subscriber-related functions, but the description here will focus on the functions particularly required for interfacing with communal telephones. The power supply circuit 16 includes a pair of complementary transistors 12, 13 and a resistor 14.
.. 15, and performs all of the supply of communication current to the telephones 1 and 2 and subscriber monitoring (including reception of dial pulses). 2-wire 4-wire conversion circuit 18#-1 Matched termination for audio frequency, allowing calls between telephone 1 or 2 and a third telephone other than 1 and 2? A feature that makes it possible? Equipped with Does the PCM encoder/decoder 19 perform analog/digital conversion with the 2-wire/4-wire conversion circuit 18? Execute.

スイッチ22は1.2[60インターの呼出し信号送出
時にスイッチ6.7と連動してリンガ音源24を加入者
線に接続する機能を有する。具体的には、スイッチ6.
7を閉成しかつスイッチ8.9を開放するとともしこ、
0.5秒間スイッチ26ij◎側に閉成し、スイッチ2
2は■側に閉成する様に制御する。
The switch 22 has the function of connecting the ringer sound source 24 to the subscriber line in conjunction with the switch 6.7 when a 1.2 [60 inter] calling signal is sent out. Specifically, switch 6.
When 7 is closed and switch 8.9 is opened,
Close switch 26ij◎ side for 0.5 seconds, then switch 2
2 is controlled so that it closes to the ■ side.

次の05秒間はスイッチ26は■側に閉成し、スイッチ
22は■側に閉成する様に制御する。
For the next 05 seconds, the switch 26 is controlled to be closed to the ■ side, and the switch 22 is controlled to be closed to the ■ side.

以下、同様にリンガ音源と地気?0.5秒周期で送出す
ることにより前記60インターの呼出信号?送出する。
Below, the linga sound source and earth qi? The call signal of the 60 Inter is transmitted at a period of 0.5 seconds? Send.

10は呼出し信号送出に対する応答全検出する応答検出
回路であジ、11は検出用カケ示す。17.23は電池
を示す。
Reference numeral 10 denotes a response detection circuit for detecting all responses to the sending of the calling signal, and 11 indicates a detection chip. 17.23 indicates a battery.

加入者回路25の共同電話機間での相互通話時の動作を
第2図全周いて説明する。
The operation of the subscriber circuit 25 during mutual communication between communal telephones will be explained with reference to FIG.

空状態ではスイッチ8,9は閉成し、スイッチ22は■
側に閉成し、26は◎lul+に閉成(−112〜17
により加入者監視及びダイヤルノ<ルス受信可能状態と
する。
In the empty state, switches 8 and 9 are closed, and switch 22 is closed.
Closed to the side, 26 closed to ◎lul+ (-112 to 17
This makes it possible to monitor subscribers and receive dial messages.

今、電話機1よV%番”112”番?前記12〜17が
検出すると、これを制御回路に通知する。
Now, phone 1, V% number "112"? When the above-mentioned 12 to 17 detect, this is notified to the control circuit.

制御回路は8,9を開放するとともに、スイッチ7.6
會閉成しかつ60インターの呼出イ8号全速出すべく前
述の操作?実行する0この時、制御回路は他の呼出信号
(例えば、IR呼出(i号送出)に関する第1の制御デ
ータとともに相互呼出しであることに示す第2の制御デ
ータを送出する。該第2の制御データは1,2間での相
互通話が完了するまで有効となるようVこする。
The control circuit opens switches 8 and 9 and switches 7 and 6.
The above operation in order to close the meeting and call 60 Inter at full speed No. 8? Execute 0 At this time, the control circuit sends out second control data indicating that it is a mutual call together with the first control data regarding another call signal (for example, IR call (issue i). The control data remains valid until the mutual communication between 1 and 2 is completed.

12〜17と電気的に並列接続した2#!4脚変換回路
18との接続・分離上実行する1組のスイッチ20.2
1’j前記第2の制御データを用いて開放制御すること
とする0丁lわち、前記特番受信後、60インタの呼出
信号により甲電話機、乙電話機lt2’を相互呼出しす
るととも+’C1前記スイッチ20.21i開放制御し
甲電話機、乙電話機1.2から加入者回路25ケ見た時
の音声周波数に対するインピーダンス紮ノ・イ・インピ
ーダンスとなす。これにより甲電話機7乙電話機1,2
は加入者回路25↓9直流の通話電流供給?受けるが、
音声に対して加入者回路25は等測的に非接続状態とな
るため、音声のレベル低下は期たさないことになる。
2# electrically connected in parallel with 12 to 17! A set of switches 20.2 for connection and separation with the four-leg conversion circuit 18
1'j The above-mentioned second control data is used to control the opening. That is, after receiving the special number, the telephone A and the telephone B lt2' are mutually called by the ringing signal of the 60 inter, and +'C1 The opening of the switches 20 and 21i is controlled to set the impedance corresponding to the voice frequency when viewing the 25 subscriber circuits from telephone A and telephone B 1.2. As a result, phone A 7 phone B 1, 2
Is the subscriber circuit 25↓9 DC call current supply? I accept it, but
Since the subscriber circuit 25 is isometrically disconnected from the voice, a drop in the voice level is not expected.

以上、第2図による本発明の実施例は通話電流供給(B
81部全ハイ・インピーダンス化とし、2線4線変換(
H)部にて整合終端するようにしたものである。
As described above, the embodiment of the present invention shown in FIG.
All 81 sections are high impedance, and 2-wire 4-wire conversion (
The matching termination is performed at part H).

尚、他の構成業有する加入者回路に対し、本発明による
共同電話機の相互通話方式を適用しても同等の効果が得
られることは当然である。
It goes without saying that the same effect can be obtained even if the mutual communication system of the communal telephone according to the present invention is applied to a subscriber circuit having another component.

(7)発明の効果 本発明によれば、TDダ換横機用加入者回路おいても共
同電話機間での相互通話時に加入者回路を音声周波数に
対してノ・イ・インピーダンス化しうるため、音声レベ
ルの低下なしに通話可能となしうる。
(7) Effects of the Invention According to the present invention, even in the subscriber circuit for a TD/DC side machine, the subscriber circuit can be made to have no impedance with respect to the voice frequency during mutual communication between communal telephones. It is possible to make a call without reducing the voice level.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図は従来のを間分割形交換機での相互通話全説明す
るための構成図、第2図は本発明の一実施例?示す構成
図である。 図面において、1は共同電話機の甲、2Vi共同電話機
の乙、3r/″iネツトワーク、4は発信レジスタトラ
ンク(ORT)、5は呼出し信号トランク(RGTI、
6,7,8,9,20,21.22はスイッチ、10は
応答検出回路、11は応答検出出力、12.131′:
jトランジスタ、14.15は抵抗器、161”i通話
電流供給回路、17 、23は直流電源、18は2線4
線変換回路、19は符号・復号器、24はリンガ音源、
25は加入者回路?そitぞれ示す。 第1頁の続き ■出 願 人 日本電気株式会社 東京都港区芝五丁目33番1号 @出 願 人 株式会社日立製作所 東京都千代田区丸の内−丁目5 番1号
Fig. 1 is a block diagram for explaining all mutual communication in a conventional split-type switch, and Fig. 2 is an embodiment of the present invention. FIG. In the drawing, 1 is a public telephone A, 2Vi is a public telephone O, 3r/''i network, 4 is an originating register trunk (ORT), and 5 is a ringing signal trunk (RGTI,
6, 7, 8, 9, 20, 21.22 are switches, 10 is a response detection circuit, 11 is a response detection output, 12.131':
j transistor, 14.15 is a resistor, 161"i communication current supply circuit, 17 and 23 are DC power supplies, 18 is 2-wire 4
line conversion circuit, 19 code/decoder, 24 ringer sound source,
Is 25 the subscriber circuit? Each of them is shown below. Continued from page 1 ■Applicant NEC Corporation 5-33-1 Shiba, Minato-ku, Tokyo @Applicant Hitachi Ltd. 5-1 Marunouchi-chome, Chiyoda-ku, Tokyo

Claims (1)

【特許請求の範囲】 通話電流供給回路及び2線4線変換回路全具備するディ
ジタル交換機用の加入者回路において、前記通話電流供
給回路上音声周波数に対しハイ働インピーダンス終端と
なし、前記2線4線変換回路全音声周波数に対し整合終
端となし、該通話電流供給回路と該2線4線変換回路t
−it気的に並列接続する接点を具備し、共同電話機間
の相互通話時には制御回路の第1の指令により該接点全
駆動して該2線4線変換回路全切離し、加入者回路全音
声周波数に対してハイ働インピーダンス終端となし、共
同電話機間の相互通話方式外には制御回通 路の第2の指令により該電話電流供給回路と該2線4線
変換回路全電気的に並列接続するように核接点?駆動し
、加入者回路全音声周波数に対して整合終端させること
全特徴とする共同電話機の相互通話方式。
[Scope of Claims] In a subscriber circuit for a digital exchange equipped with both a speech current supply circuit and a two-wire four-wire conversion circuit, the speech current supply circuit is provided with a high working impedance termination for voice frequencies, and the two-wire four-wire The line conversion circuit has matching termination for all audio frequencies, and the communication current supply circuit and the 2-wire and 4-wire conversion circuit t.
-It is equipped with contacts that are electrically connected in parallel, and when a mutual call is made between communal telephones, the contacts are fully driven by the first command of the control circuit, and the 2-wire and 4-wire conversion circuits are completely disconnected, and the subscriber circuit is fully connected at all voice frequencies. The telephone current supply circuit and the 2-wire 4-wire conversion circuit are all electrically connected in parallel by the second command of the control circuit, except for the mutual communication system between communal telephones. Nuclear contact? An intercommunication system for communal telephones, which is characterized by a matched termination for all voice frequencies of subscriber circuits.
JP57116671A 1982-07-05 1982-07-05 Mutual communication system of party line telephone Granted JPS598462A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP57116671A JPS598462A (en) 1982-07-05 1982-07-05 Mutual communication system of party line telephone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP57116671A JPS598462A (en) 1982-07-05 1982-07-05 Mutual communication system of party line telephone

Publications (2)

Publication Number Publication Date
JPS598462A true JPS598462A (en) 1984-01-17
JPH0359633B2 JPH0359633B2 (en) 1991-09-11

Family

ID=14693008

Family Applications (1)

Application Number Title Priority Date Filing Date
JP57116671A Granted JPS598462A (en) 1982-07-05 1982-07-05 Mutual communication system of party line telephone

Country Status (1)

Country Link
JP (1) JPS598462A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5938252A (en) * 1996-08-22 1999-08-17 Asmo Co., Ltd. Door member locking/unlocking apparatus

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5735456A (en) * 1980-08-11 1982-02-26 Fujitsu Ltd Ring trip circuit

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5735456A (en) * 1980-08-11 1982-02-26 Fujitsu Ltd Ring trip circuit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5938252A (en) * 1996-08-22 1999-08-17 Asmo Co., Ltd. Door member locking/unlocking apparatus

Also Published As

Publication number Publication date
JPH0359633B2 (en) 1991-09-11

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