JPH04207659A - Line terminal equipment - Google Patents
Line terminal equipmentInfo
- Publication number
- JPH04207659A JPH04207659A JP33818790A JP33818790A JPH04207659A JP H04207659 A JPH04207659 A JP H04207659A JP 33818790 A JP33818790 A JP 33818790A JP 33818790 A JP33818790 A JP 33818790A JP H04207659 A JPH04207659 A JP H04207659A
- Authority
- JP
- Japan
- Prior art keywords
- line
- request signal
- ringing
- detection section
- polarity
- 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
Links
- 238000001514 detection method Methods 0.000 claims abstract description 49
- 230000005856 abnormality Effects 0.000 claims description 7
- 230000002159 abnormal effect Effects 0.000 claims 1
- 230000007257 malfunction Effects 0.000 abstract description 3
- 238000003708 edge detection Methods 0.000 description 8
- 230000005540 biological transmission Effects 0.000 description 5
- 238000011084 recovery Methods 0.000 description 5
- 244000145845 chattering Species 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 241000894007 species Species 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は電話回線に接続されノーリンギング通信サービ
スを利用することのできる回線端末装置に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a line terminal device that is connected to a telephone line and can utilize a no-ringing communication service.
従来の技術
近年、ガス、水道等の自動検針等においてノーリンギン
グ通信サービスが普及し始めている。このサービスは従
来から家庭にある電話機に回線端末装置を併設して行わ
れている。サービスの特徴は電話回線の空き時間を利用
していること、電話機の利用を優先的に扱うこと、電話
機のベルを鳴らさずに回線端末装置に着信することなど
である。2. Description of the Related Art In recent years, no-ringing communication services have become popular for automatic meter reading of gas, water, etc. This service has traditionally been provided by attaching a line terminal device to a telephone in the home. Characteristics of the service include making use of free time on telephone lines, giving priority to the use of telephones, and receiving calls at line terminals without ringing the telephone bell.
従来のこの種の回線端末装置を第３図に示す。A conventional line terminal device of this type is shown in FIG.
回線端末装置は、接続された電話回線１間の電位差を検
出し、極性反転時にノーリンギング接続開始要求信号を
発し、また次の極性復旧時にノーリンギング接続終了要
求信号を発する極性反転検出部２と、電話回線１上のイ
ンピーダンス制御を行うオフフック制御部３と、データ
の送受信を行う送受信部４と、極性反転検出部２からの
ノーリンギング接続開始要求信号を受けるとオフフック
制御部３により電話回線１を半閉結接続し、また送受信
部４を駆動することによってノーリンギング呼出信号を
検出し以後通信相手先とのリンクを確立させ、あるいは
たとえ通信中であっても極性反転検出部２からのノーリ
ンギング接続終了要求信号を受けるとオフフック制御部
３により電話回線１を開放し、ノーリンギング通信を終
了させる主制御部５とを備えている。The line terminal device includes a polarity reversal detector 2 that detects the potential difference between the connected telephone lines 1, issues a no-ringing connection start request signal when the polarity is reversed, and issues a no-ringing connection end request signal when the next polarity is restored; Off-hook control unit 3 performs impedance control on line 1, transmission/reception unit 4 performs data transmission and reception, and when receiving a no-ringing connection start request signal from polarity reversal detection unit 2, off-hook control unit 3 half-closes telephone line 1. By connecting and driving the transmitting/receiving unit 4, a no-ringing call signal is detected and a link with the communication partner is established thereafter, or even if communication is in progress, a no-ringing connection termination request signal is sent from the polarity reversal detecting unit 2. The main controller 5 is configured to open the telephone line 1 by the off-hook controller 3 and terminate the no-ringing communication when the telephone line 1 is received.
次に第４図に極性反転検出部２の構成を、第５図にその
動作を説明するタイムチャートを示す。Next, FIG. 4 shows the configuration of the polarity reversal detection section 2, and FIG. 5 shows a time chart illustrating its operation.
０点は電話回線間の電位差であり通常は４８ｖ程度を保
持している。全極性が反転または復旧すると、極反エツ
ジ検出回路２１はその変化点において（例えば回線間の
電位差がＯｖから３２ｖになる箇所で）０点に示すよう
なＨパルスを発生する。これは電話回線との接続をどち
らの方向でも可能とするために、２点間の電位差の変化
をとらえるものである。Ｔフリップフロップ２２では０
点に示すようにはじめの極性反転に対応したＨパルスの
立ち上がりから次の極性復旧に対応したＨパルスの立ち
上がりまでの期間Ｈレベルを保持する。すなわち電話回
線の極性が反転している関しゆうＨレベルを保持し、極
性が復旧している間じゆうしレベルを保持する。立ち上
がりエツジ検出部２３では、０点のＬレベルからＨレベ
ルへの変化時に０点のようなＨパルスをノーリンギング
接続要求信号として出力する。また立ち下がり工゛ツジ
検出部２４では０点のＨレベルからＬレベルへの変化時
に０点のようなＨパルスをノーリンギング接続終了要求
信号として出力する。上記構成において極性反転検出部
２は、はじめの極性反転時にノーリンギング接続開始要
求信号を発し、次の極性復旧時にノーリンギング接続終
了要求信号を発するのである。The 0 point is the potential difference between the telephone lines and is normally maintained at about 48V. When all polarities are reversed or restored, the polar edge detection circuit 21 generates an H pulse as shown at the 0 point at the point of change (for example, at a point where the potential difference between the lines changes from Ov to 32V). This detects changes in the potential difference between two points in order to enable connection to a telephone line in either direction. 0 in T flip-flop 22
As shown in the dot, the H level is maintained for a period from the rise of the H pulse corresponding to the first polarity reversal to the rise of the H pulse corresponding to the next polarity restoration. That is, when the polarity of the telephone line is reversed, the high level is held, and while the polarity is restored, the normal level is held. The rising edge detection section 23 outputs an H pulse such as that at the 0 point as a no-ringing connection request signal when changing from the L level at the 0 point to the H level. Further, the falling edge detection section 24 outputs an H pulse such as that at the 0 point as a no-ringing connection termination request signal when changing from the H level at the 0 point to the L level. In the above configuration, the polarity reversal detection section 2 issues a no-ringing connection start request signal at the first polarity inversion, and issues a no-ringing connection end request signal at the next polarity restoration.
発明が解決しようとする課題
しかしながらこのような従来の回線端末装置では、通信
中の回線電圧の瞬断・復旧に反応して極反エツジ検出部
がＨパルスを出力してしまうので、結果的に無条件に通
信を終了させなければならない。Problems to be Solved by the Invention However, in such conventional line terminal devices, the polar edge detection section outputs an H pulse in response to momentary interruption and restoration of line voltage during communication, resulting in Communication must be terminated unconditionally.
また極性反転時や極性復旧時に、チャタリング等により
極反エツジ検出部において２つのＨパルスを出力した場
合、次の極性復旧や極性反転をそれぞれ逆のものとみな
してしまう、これは電話回線上のノイズや内部回線上の
ノイズに関しても同様である。Furthermore, if two H pulses are output in the extreme edge detection section due to chattering or the like during polarity reversal or polarity recovery, the next polarity recovery or polarity reversal will be regarded as the opposite. The same applies to noise and noise on internal lines.
本発明ｔよ上記課題を解決するもので、回線電圧の瞬断
・復旧時に無条件に通信を終了することを回避し、また
電話回線の極性反転や極性復旧をそれぞれを逆のものと
みなして誤動作しない回線端末装置を提供することを目
的としている。 “課題を解決するための手段
本発明の回線端末装置は上記目的を達成するために、は
じめの極性反転時（すなわち奇数回目の回線間電位差変
化点）にも次の極性復旧時（すなわち偶数回目の回線間
電位差変化点）にもノーリンギング接続開始要求信号を
発する極性反転検出部を備えたものである。The present invention solves the above-mentioned problems, and avoids unconditionally terminating communication when the line voltage is momentarily interrupted or restored, and also treats polarity reversal and polarity recovery of the telephone line as opposites. The purpose is to provide a line terminal device that does not malfunction. “Means for Solving the Problems” In order to achieve the above object, the line terminal device of the present invention has the following features: both at the time of the first polarity reversal (i.e., at the odd-numbered line potential difference change point) and at the time of the next polarity restoration (i.e., at the even-numbered change point). The circuit is also equipped with a polarity reversal detection section that issues a no-ringing connection start request signal at a point where the potential difference between the lines changes.
また電話回線間の電位差が一定時間、所定値以下になっ
た場合、ノーリンギング接続終了要求信号を発する回線
断検出部を備えている。Furthermore, the telephone line disconnection detection section is provided which issues a no-ringing connection termination request signal when the potential difference between the telephone lines becomes less than a predetermined value for a certain period of time.
また電話回線間の電位差が一定時間、所定値以上になっ
た場合、ノーリンギング接続終了要求信号を発する回線
電圧異常検出部を備えている。The telephone line also includes a line voltage abnormality detection unit that issues a no-ringing connection termination request signal when the potential difference between the telephone lines exceeds a predetermined value for a certain period of time.
また電話回線を介した通信相手先との非通信状態が所定
時間以上経過した場合、ノーリンギング接続終了要求信
号を発する非通信状態検出部を備えている。Furthermore, if a non-communication state with a communication partner via a telephone line has elapsed for a predetermined period of time or more, a non-communication state detection section is provided that issues a no-ringing connection termination request signal.
また電源電圧が所定値以下になった場合、ノーリンギン
グ接続終了要求信号を発する電源断検出部を備えている
。The device also includes a power-off detection unit that issues a no-ringing connection termination request signal when the power supply voltage falls below a predetermined value.
また接続された装置のオフフック状態が検出された場合
、ノーリンギング接続終了要求信号を発するオフフック
制御部を備えている。Further, the off-hook control section is provided which issues a no-ringing connection termination request signal when an off-hook state of a connected device is detected.
作用
本発明は上記した構成により、はじめの極性反転時にも
次の極性復旧時にもノーリンギング接続を開始ないし継
続することになる。つまり極反検出部から出力される信
号によりノーリンギング通信を終了させてしまうことは
ない。ノーリンギング通信を終了させる要因は、（１）
回線断状態が一定時間以上継続した時、（２）回線間の
電位差が一定時間以上継続して所定値を超えた時、（３
）通信相手先からのキャリア信号断等、非通信状態が一
定時間以上継続した時、（４）内部に持つ電源電圧が所
定値以下になった時、（５）電話等接続された装置のオ
フフック状態が検出された時である。Effect of the Invention With the above-described configuration, the present invention starts or continues a no-ringing connection both at the time of initial polarity reversal and at the time of subsequent polarity restoration. In other words, no-ringing communication is not terminated due to the signal output from the polar anti-polarity detection section. The factors that cause no-ringing communication to end are (1)
(2) When the line disconnection continues for a certain period of time or more, (2) When the potential difference between the lines exceeds a predetermined value for a certain period of time or more, (3)
) When a non-communication state continues for a certain period of time, such as when the carrier signal from the communication partner is cut off, (4) When the internal power supply voltage drops below a predetermined value, (5) When a connected device such as a telephone goes off-hook. This is when the condition is detected.
よってはじめの極性反転時にも次の極性復旧時にも一旦
電話回線を半閉結接続し、ノーリンギング呼出信号を検
出できるよう、通信相手先とのリンク確立待機状態に入
るが、もし極性復旧時であったならば通信相手先からの
ノーリンギング呼出信号ないしキャリア信号は来ないの
で、一定時間経過後、非通信状態検出部からの出力によ
り電話回線を開放し、ノーリンギング通信を終了させる
よう作用する。Therefore, at the time of the first polarity reversal and the next time the polarity is restored, the telephone line is temporarily connected in a semi-closed state, and the telephone line enters a standby state for establishing a link with the communication partner so that a no-ringing call signal can be detected. In this case, no no-ringing call signal or carrier signal is received from the communication partner, so after a certain period of time has elapsed, the output from the non-communication state detection unit opens the telephone line and terminates the no-ringing communication.
実施例
以下、本発明の一実施例を添付図面にもとづいて説明す
る。第１図において、第３図の従来例で示した機能と同
一の機能を持つブロックは同一の符号を付与する。従来
例同様、電話回線１上のインピーダンス制御を行うオフ
フック制御部３と、データの送受信を行う送受信部４と
、ノーリンギング接続開始要求信号またはノーリンギン
グ接続終了要求信号に対応してオフフック制御部３の接
続制御を行い、送受信部４を駆動する主制御部５を備え
ている。極性反転検出部６は電話回線１に接続され、は
じめの極性反転時にはしめの極性反転時（すなわち奇数
回目の回線電位差変化点）にも次の極性反転時（すなわ
ち偶数回目の回線電位差変化点）にもノーリンギング接
続開始要求信号を発するもので、第４図の従来例で示し
た極性エツジ検出回路２１と等価な構成である。第２図
にその動作を説明するタイムチャートを示す。０点は電
話回線間の電位差であり通常は４８Ｖ程度を保持してい
る。金種性が反転または復旧すると、極反エツジ検出回
路２１はその変化点において（例えば回線間の電位差が
Ｏｖから３２ｖになる箇所で）０点に示すようなＨパル
スを発生する。このＨパルスはそのままノーリンギング
接続開始要求として出力される。Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. In FIG. 1, blocks having the same functions as those shown in the conventional example of FIG. 3 are given the same reference numerals. Similar to the conventional example, the off-hook control section 3 performs impedance control on the telephone line 1, the transmission/reception section 4 performs data transmission and reception, and the off-hook control section 3 is connected in response to a no-ringing connection start request signal or a no-ringing connection end request signal. It includes a main control section 5 that performs control and drives the transmitter/receiver section 4 . The polarity reversal detection section 6 is connected to the telephone line 1, and detects the polarity at the first polarity reversal, at the final polarity reversal (i.e., at the odd-numbered line potential difference change point), and at the next polarity reversal (i.e., at the even-numbered line potential difference change point). It also issues a no-ringing connection start request signal, and has a configuration equivalent to the polarity edge detection circuit 21 shown in the conventional example of FIG. FIG. 2 shows a time chart explaining the operation. The 0 point is the potential difference between the telephone lines and is normally maintained at about 48V. When the denomination is reversed or restored, the polar edge detection circuit 21 generates an H pulse as shown at the 0 point at the point of change (for example, at a point where the potential difference between the lines changes from Ov to 32V). This H pulse is output as it is as a no-ringing connection start request.
さらに電話回線間の電位差が一定時間所定値以下になっ
た場合、Ｈパルスのノーリンギング接続終了要求信号を
発する回線断検出部７、電話回線間の電位差が一定時開
所定値以上になった場合、Ｈパルスのノーリンギング接
続終了要求信号を発する回線電圧異常検出部８、電話回
線を介した通信相手先との非通信状態が所定時間以上経
過した場合、Ｈパルスのノーリンギング接続終了要求信
号を発する非通信状態検出部９、電′ａｔ圧が所定値以
下になった場合、Ｈパルスのノーリンギング接続終了要
求信号を発する電源断検出部１０、接続された装置のオ
フフック状態が検出された場合、Ｈパルスのノーリンギ
ング接続終了要求信号を発するオフフック検出部１１を
備えている。回線断検出部７、回線電圧異常検出部８、
非通信状態検出部９、電源断検出部１０、オフフック検
出部１１はそれぞれの状態が検出された場合Ｈパルスの
ノーリンギング接続終了要求信号を送出するが、これら
すべてを正論理のＯＲゲート１２で結び、少なくとも１
つ以上の事象発生があれば、ノーリンギング接続終了要
求信号を主制御部５に伝え、ノーリンギング通信を終了
させるものである。Furthermore, if the potential difference between the telephone lines is below a predetermined value for a certain period of time, a line disconnection detection section 7 issues an H pulse no-ringing connection termination request signal; A line voltage abnormality detection unit 8 that issues a pulse no-ringing connection termination request signal, and a non-communication state that issues an H-pulse no-ringing connection termination request signal when a non-communication state with the communication partner via the telephone line has elapsed for a predetermined period of time or more. Detection unit 9, when the voltage at voltage falls below a predetermined value, outputs an H-pulse no-ringing connection termination request signal Power-off detection unit 10, when an off-hook state of the connected device is detected, an H-pulse no-ringing It includes an off-hook detection section 11 that issues a connection termination request signal. line disconnection detection unit 7, line voltage abnormality detection unit 8,
The non-communication state detection section 9, power-off detection section 10, and off-hook detection section 11 send out an H-pulse no-ringing connection termination request signal when their respective states are detected, but all of these are connected by a positive logic OR gate 12. , at least 1
If three or more events occur, a no-ringing connection termination request signal is transmitted to the main control unit 5, and the no-ringing communication is terminated.
上記構成において極性反転検出部６の機能により、ノー
リンギング通信の開始は電話回線間電位の変化点で必ず
行なわれるので、発生した回線間電位の変化がはじめの
極性反転なのか次の極性復旧なのかを区別する必要がな
い。また極性反転時や極性復旧時に発生するチャタリン
グや瞬断、電話回線上のノイズや内部回路上のノイズ等
によってノーリンギング接続開始要求信号が誤った箇所
で出力されても、もし非通信中であれば一旦接続後タイ
ムアウトで切断できるし通信中であれば無視して通信状
態を継続できるため極性反転に伴うあらゆる誤動作を回
避できる。In the above configuration, due to the function of the polarity reversal detection section 6, the start of no-ringing communication is always performed at a change point in the potential between the telephone lines, so whether the change in the potential between the lines that occurs is the first polarity reversal or the next polarity restoration. There is no need to distinguish. In addition, even if the no-ringing connection start request signal is output at the wrong location due to chattering or instantaneous interruptions that occur during polarity reversal or polarity recovery, noise on the telephone line, noise on the internal circuit, etc., if the no-ringing connection start request signal is output at the wrong location, Once connected, it can be disconnected when a timeout occurs, and if communication is in progress, it can be ignored and the communication state can be continued, so any malfunctions caused by polarity reversal can be avoided.
またノーリンギング通信終了に関しては、電話回線間電
位の変化点（極性復旧）だけで判断するのではなく、前
記した非通信状態タイムアウトの他、回線断、回線電圧
異常、本回線端末装置の電源断、本回線端末装置に接続
された装置のオフフック検出等のいずれかの事象発生で
終了させるものであるからノーリンギング通信の接続制
御に関し、システム全体としての動作はより確実に実現
される。Regarding the termination of no-ringing communication, it is determined not only by the point of change in the potential between telephone lines (polarity recovery), but also by the above-mentioned non-communication state timeout, line disconnection, line voltage abnormality, power outage of the line terminal equipment, etc. Since the process is terminated upon the occurrence of any event such as off-hook detection of a device connected to the line terminal device, the operation of the entire system can be realized more reliably with respect to connection control of no-ringing communication.
発明の効果
以上の実施例から明らかなように、本発明によればノー
リンギング通信開始の判定を電話回線間電位の変化の都
度行なうので、万一ノイズ・瞬断等でノーリンギング通
信の中断を余儀なくされても、次回必ず最初の極性反転
を検出し損なうことはなくなり、システム全体としての
信輔性が向上する。Effects of the Invention As is clear from the embodiments described above, according to the present invention, the determination to start no-ringing communication is made every time there is a change in the potential between the telephone lines, so in the unlikely event that no-ringing communication is forced to be interrupted due to noise, instantaneous interruption, etc. However, the first polarity reversal will never be missed next time, improving the reliability of the system as a whole.
またノーリンギング通信終了に関し、複合要因を検出し
条件判定するため、ノーリンギング通信の接続制御に関
しより効率性が向上する。Furthermore, since complex factors are detected and conditions are determined regarding the termination of no-ringing communication, the efficiency of connection control for no-ringing communication is further improved.
第１図は本発明の一実施例の回線端末装置の構成を示す
ブロック図、第２図は同装置における極性判定検出部の
動作を説明するタイムチャート、第３図は従来の回線端
末装置の構成を示すブロック図、第４図は従来の回線端
末装置における極性判定検出部の構成を示すブロック図
、第５図は従来の回線端末装置における極性判定検出部
の動作を説明するタイムチャートである。
１・・・・・・電話回線、３・・・・・・オフフック制
御部、４・・・・・・送受信部、５・・・・・・主制御
部、６・・・・・・極性反転検出部、７・・・・・・回
線断検出部、８・・・・・・回線電圧異常検出部、９・
・・・・・非通信状態検出部、１０・・・・・・電源断
検出部、１１・・・・・・オフフック検出部２１・・・
・・・種属エツジ検出回路。
代理人の氏名 弁理士 小鍜治 明 ほか２名ｍ１図FIG. 1 is a block diagram showing the configuration of a line terminal device according to an embodiment of the present invention, FIG. 2 is a time chart explaining the operation of the polarity judgment detection section in the same device, and FIG. FIG. 4 is a block diagram showing the configuration of a polarity determination detection section in a conventional line terminal device, and FIG. 5 is a time chart illustrating the operation of the polarity determination detection section in a conventional line terminal device. . 1...Telephone line, 3...Off-hook control section, 4...Transmission/reception section, 5...Main control section, 6...Polarity Reversal detection section, 7... Line disconnection detection section, 8... Line voltage abnormality detection section, 9.
...Non-communication state detection unit, 10...Power cut-off detection unit, 11...Off-hook detection unit 21...
...Species edge detection circuit. Name of agent: Patent attorney Akira Okaji and 2 others
Claims (6)
時にノーリンギング接続開始要求信号を発する極性反転
検出部と、前記電話回線上のインピーダンス制御を行う
オフフック制御部と、データの送受信を行う送受信部と
、前記極性反転検出部からのノーリンギング接続開始要
求信号に対し前記オフフック制御部の制御を行い、前記
送受信部を駆動する主制御部とを備えた回線端末装置。(1) A polarity reversal detection unit that detects the polarity of the telephone line and issues a no-ringing connection start request signal when the polarity is reversed or restored, and an off-hook control unit that controls the impedance on the telephone line, transmitting and receiving data. A line terminal device comprising: a transmitter/receiver; and a main controller that controls the off-hook controller in response to a no-ringing connection start request signal from the polarity reversal detector and drives the transmitter/receiver.
なった場合、ノーリンギング接続終了要求信号を発する
回線断検出部と、前記回線断検出部からのノーリンギン
グ接続終了要求信号に対し前記オフフック制御部の制御
を行い、回線を開放する主制御部とを備えた回線端末装
置。(2) a line disconnection detection unit that issues a no-ringing connection termination request signal when the potential difference between the telephone lines remains disconnected for a certain period of time; and the off-hook in response to the no-ringing connection termination request signal from the line disconnection detection unit. A line terminal device that includes a main control unit that controls the control unit and opens the line.
超える異常電圧を検出した場合、ノーリンギング接続終
了要求信号を発する回線電圧異常検出部と、前記回線電
圧異常検出部からのノーリンギング接続終了要求信号に
対し前記オフフック制御部の制御を行い、回線を開放す
る主制御部とを備えた回線端末装置。(3) A line voltage abnormality detection unit that issues a no-ringing connection termination request signal when an abnormal voltage exceeding a predetermined value is detected for which the potential difference between the telephone lines continues for a certain period of time; and a no-ringing connection termination from the line voltage abnormality detection unit. A line terminal device comprising a main control unit that controls the off-hook control unit in response to a request signal and releases the line.
定時間以上経過した場合、ノーリンギング接続終了要求
信号を発する非通信状態検出部と、前記非通信状態検出
部からのノーリンギング接続終了要求信号に対し前記オ
フフック制御部の制御を行い、回線を開放する主制御部
とを備えた回線端末装置。(4) A non-communication state detection section that issues a no-ringing connection termination request signal when a non-communication state with the communication partner via the telephone line has elapsed for a predetermined period of time or more; and a no-ringing connection termination request from the non-communication state detection section. A line terminal device comprising a main control unit that controls the off-hook control unit in response to a signal and opens the line.
ング接続終了要求信号を発する電源断検出部と、前記電
源断検出部からのノーリンギング接続終了要求信号に対
し前記オフフック制御部の制御を行い、回線を開放する
主制御部とを備えた回線端末装置。(5) When the power supply voltage drops below a predetermined value, a power-off detection section that issues a no-ringing connection termination request signal, and the off-hook control section is controlled in response to the no-ringing connection termination request signal from the power-off detection section, and the line A line terminal device equipped with a main control unit that opens the line.
場合、ノーリンギング接続終了要求信号を発するオフフ
ック検出部と、前記オフフック制御部からのノーリンギ
ング接続終了要求信号に対し前記オフフック制御部の制
御を行い、回線を開放する主制御部とを備えた回線端末
装置。(6) When an off-hook state of another connected device is detected, an off-hook detection section that issues a no-ringing connection termination request signal and a control of the off-hook control section in response to a no-ringing connection termination request signal from the off-hook control section; , and a main control unit that opens the line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2338187A JP3006087B2 (en) | 1990-11-30 | 1990-11-30 | Line terminal equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2338187A JP3006087B2 (en) | 1990-11-30 | 1990-11-30 | Line terminal equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04207659A true JPH04207659A (en) | 1992-07-29 |
| JP3006087B2 JP3006087B2 (en) | 2000-02-07 |
Family
ID=18315744
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2338187A Expired - Lifetime JP3006087B2 (en) | 1990-11-30 | 1990-11-30 | Line terminal equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3006087B2 (en) |
-
1990
- 1990-11-30 JP JP2338187A patent/JP3006087B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JP3006087B2 (en) | 2000-02-07 |
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