JPS63164736A - Data transmission system - Google Patents
Data transmission systemInfo
- Publication number
- JPS63164736A JPS63164736A JP31310186A JP31310186A JPS63164736A JP S63164736 A JPS63164736 A JP S63164736A JP 31310186 A JP31310186 A JP 31310186A JP 31310186 A JP31310186 A JP 31310186A JP S63164736 A JPS63164736 A JP S63164736A
- Authority
- JP
- Japan
- Prior art keywords
- data
- transmission
- central processing
- processing unit
- data transmission
- 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.)
- Pending
Links
- 230000005540 biological transmission Effects 0.000 title claims abstract description 105
- 238000000034 method Methods 0.000 claims description 5
- 238000004891 communication Methods 0.000 abstract description 14
- 238000010586 diagram Methods 0.000 description 7
- 238000000926 separation method Methods 0.000 description 5
- 125000004122 cyclic group Chemical group 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 1
Landscapes
- Small-Scale Networks (AREA)
Abstract
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、ループ式データ伝送方式に関する。[Detailed description of the invention] [Industrial application field] The present invention relates to a loop data transmission system.
特に、１台の中央処理装置と複数の端末装置との間でｌ
対Ｎの全二重データ通信を行う手段に関する。In particular, between one central processing unit and multiple terminal devices,
The present invention relates to means for performing N-to-N full-duplex data communication.
本発明は、１台の中央処理装置とこれにループ伝送路を
介して接続された複数の端末装置との間のデータ通信手
段において、
ループ伝送路に下りと上りの専用のチャネルを設け、ま
た上りチャネルでのデータ衝突を防止することにより、
中央処理装置と端末装置間で全二重データ通信を行うこ
とができるようにしたものである。The present invention provides a means for data communication between one central processing unit and a plurality of terminal devices connected to the central processing unit via a loop transmission line, in which dedicated downlink and uplink channels are provided in the loop transmission line, and By preventing data collisions on the upstream channel, it is possible to perform full-duplex data communication between the central processing unit and the terminal equipment.
従来、この種のループ式データ伝送方式は、上りと下り
とで独立のデータ回線に分けずに同一のデータ回線でデ
ータ送受信を行っていた。Conventionally, in this type of loop data transmission system, data was sent and received over the same data line without separating upstream and downstream data lines into independent data lines.
このような従来のループ式データ伝送方式は、同一のデ
ータ回線でデータ送受信を行っているので、１対Ｎのデ
ータ通信を行う場合に、中央処理装置から端末装置へデ
ータ転送中はすべての端末装置は受信動作のみ行い、中
央処理装置からのデータ送信が終結後に中央処理装置が
選択した端末装置が送信動作し、端末装置がデータを送
信終了後に中央処理装置が次の端末装置を選択してこの
端末装置がデータを送信し、これを繰り返す半二重通信
動作であり、全二重通信動作の伝送制御手順を持つ中央
処理装置および端末装置を接続することができない欠点
がある。In such a conventional loop data transmission method, data is sent and received over the same data line, so when performing 1-to-N data communication, all terminals are transferred from the central processing unit to the terminal device. The device only performs the receiving operation, and after the data transmission from the central processing unit is completed, the terminal device selected by the central processing unit performs the transmitting operation, and after the terminal device has finished transmitting the data, the central processing unit selects the next terminal device. This terminal device transmits data and repeats it in a half-duplex communication operation, and has the disadvantage that it is not possible to connect the central processing unit and the terminal device, which have a transmission control procedure for full-duplex communication operation.
本発明はこのような欠点を除去するもので、１対Ｎのデ
ータ通信を全二重通信動作で行えるデータ伝送方式を提
供することを目的とする。The present invention aims to eliminate such drawbacks, and aims to provide a data transmission system that can perform 1-to-N data communication in full-duplex communication operation.
本発明は、中央処理装置に接続されたひとつの第一デー
タ伝送装置と、複数の端末装置にそれぞれ接続された第
二データ伝送装置と、上記第一および第二データ伝送装
置が挿入されたループ伝送路とを備えたデータ伝送方式
において、上記ループ伝送路は、上記第一データ伝送装
置の送信部から送出され上記第二データ伝送装置の受信
部が受信するデータ信号が通過する第一回線および上記
第二データ伝送装置の送信部から送出され上記第一デー
タ伝送装置の受信部が受信するデータ信号が通過する第
二回線とを別に備え、上記第二伝送装置は、データ信号
の送出時にキャリア識別信号を上記第二回線に送出する
送出手段、上記第二回線上のキャリア識別信号の有無を
判別する判別手段およびこの自装置の判別手段の判別結
果に基づき自装置の送信部からのデータ送出を許可また
は禁止する制御手段を備えたことを特徴とする。The present invention includes a first data transmission device connected to a central processing unit, a second data transmission device connected to a plurality of terminal devices, and a loop into which the first and second data transmission devices are inserted. In the data transmission method, the loop transmission path includes a first line through which a data signal transmitted from the transmitting section of the first data transmitting device and received by the receiving section of the second data transmitting device passes; A second line is separately provided, through which a data signal transmitted from the transmitting section of the second data transmitting device and received by the receiving section of the first data transmitting device passes; A transmitting means for transmitting an identification signal to the second line, a determining means for determining the presence or absence of a carrier identification signal on the second line, and data transmission from the transmitting section of the own apparatus based on the determination result of the determining means of the own apparatus. The invention is characterized by comprising a control means for permitting or prohibiting.
すなわち、本発明のデータ伝送方式は、中央処理装置と
複数の端末装置とを接続する複数のデータ伝送装置をル
ープ状伝送路で構成したループ式サイクリック・ディジ
タル・データ伝送路で、前記データ伝送装置が前記中央
処理装置から前記端末装置への下り専用データ回線と前
記端末装置から前記中央処理装置への上り専用データ回
線とを持ち所定のタイムスロットで送受信する手段と、
前記データ伝送装置がデータ送信中を表すキャリア識別
信号を制御信号として送信する手段と、前記下り専用デ
ータ回線で前記中央処理装置を接続する前記データ伝送
装置が常時データを送信し、前記端末装置を接続する複
数の前記データ伝送装置が常時受信動作し、さらに受信
データを折り返し送信する手段と、前記上り専用データ
回線で前記端末装置を接続する前記データ伝送装置が前
記端末装置からの送信要求時に前記上り専用データ回線
上の前記キャリア識別信号を受信判定し、他の前記デー
タ伝送装置が送信動作中でない場合に前記端末装置から
の送信データを前記上り専用データ回線上に送信し、前
記端末装置からの送信要求が無いかまたは他の前記デー
タ伝送装置が送信動作中の場合に前記上り専用データ回
線上で回線を折り返し送信し、前記中央処理装置を接続
する前記データ伝送装置が常時受信動作し、さらに受信
データを折り返し出力する手段とを有していることを特
徴とする。That is, the data transmission method of the present invention is a loop-type cyclic digital data transmission path in which a plurality of data transmission devices connecting a central processing unit and a plurality of terminal devices are configured as a loop-shaped transmission path. means for the device to have a dedicated downlink data line from the central processing unit to the terminal device and a dedicated uplink data line from the terminal device to the central processing unit, and to transmit and receive data in predetermined time slots;
means for transmitting a carrier identification signal indicating that the data transmission device is transmitting data as a control signal; and a means for connecting the central processing unit through the downlink dedicated data line to constantly transmit data and control the terminal device. A plurality of connected data transmission devices always receive data, and a means for returning received data, and a data transmission device connected to the terminal device via the uplink dedicated data line receives the data at the time of a transmission request from the terminal device. Determines reception of the carrier identification signal on the uplink dedicated data line, and transmits transmission data from the terminal device onto the uplink dedicated data line if the other data transmission device is not in transmission operation, If there is no transmission request or if the other data transmission device is in a transmission operation, the data transmission device returns transmission on the uplink dedicated data line, and the data transmission device connected to the central processing unit always performs a reception operation; It is characterized in that it further includes means for returning and outputting the received data.
中央処理装置からの送信データは下り専用データ回線を
介して端末装置が常時受信できる。端末装置が送信する
データは上り専用データ回線を介して中央処理装置が受
信できるから、全二重通信を行うことができる。また、
中央処理装置が選択した端末装置からの送信は、上り専
用データ回線上にキャリア識別信号が存在しない場合に
実行され、キャリア識別信号とともに中央処理装置にデ
ータが送出される。Transmission data from the central processing unit can be constantly received by the terminal device via the downlink dedicated data line. Since the central processing unit can receive the data transmitted by the terminal device via the uplink data line, full-duplex communication can be performed. Also,
Transmission from the terminal device selected by the central processing unit is performed when there is no carrier identification signal on the uplink dedicated data line, and the data is sent to the central processing unit together with the carrier identification signal.
以下、本発明の一実施例を図面に基づき説明する。 Hereinafter, one embodiment of the present invention will be described based on the drawings.
第１図はこの実施例の構成を示すブロック構成図である
。データ伝送装置１〜４が挿入されたループ式サイクリ
ック・ディジタル・データ伝送路は、中央処理装置５を
接続するデータ伝送装置の送信部１−ａと端末装置６〜
８を接続するデータ伝送装置の受信部２−ｂ〜４−ｂと
が挿入された下り専用データ回線（以下、第１チヤネル
という、）２０と、中央処理装置５を接続するデータ伝
送装置の受信部１−ｂと端末装置６〜８を接続するデー
タ伝送装置の送信部２−ａ〜４−ａとが挿入された上り
専用データ回線（以下、第２チヤネルという。）２５と
で構成される。FIG. 1 is a block diagram showing the configuration of this embodiment. A loop type cyclic digital data transmission path into which the data transmission devices 1 to 4 are inserted connects the transmitting section 1-a of the data transmission device connecting the central processing unit 5 and the terminal devices 6 to 4.
A downlink dedicated data line (hereinafter referred to as the first channel) 20 into which the receiving units 2-b to 4-b of the data transmission device connecting the central processing unit 5 and the central processing unit 5 are connected. It is composed of an uplink dedicated data line (hereinafter referred to as a second channel) 25 into which transmitting units 2-a to 4-a of a data transmission device connecting the unit 1-b and the terminal devices 6 to 8 are inserted. .
第１チヤネル２０では、中央処理装置５からの送信デー
タを端末装置６〜８が常時受信する。第２チヤネル２５
では、端末装置６〜８の内中央処理装置５が選択した端
末装置（第１図ｔは端末装置７）が送信要求をデータ伝
送装置の送信部２−ａ〜４−ａ（第１図では送信部３−
ａ）に出力し、第２チヤネル２５上に先にキャリア識別
信号が存在しない場合に、端末装置からの送信要求を受
は付けたデータ伝送装置が端末装置からの送信データと
共にキャリア識別信号を送信し、中央処理装置５に対し
て応答する。In the first channel 20, the terminal devices 6 to 8 constantly receive transmission data from the central processing unit 5. 2nd channel 25
Then, the terminal device selected by the central processing unit 5 among the terminal devices 6 to 8 (terminal device 7 in FIG. 1) sends a transmission request to the transmitting units 2-a to 4-a (in FIG. Transmitter 3-
a), and when there is no carrier identification signal on the second channel 25, the data transmission device that has accepted the transmission request from the terminal device transmits the carrier identification signal together with the transmission data from the terminal device. and responds to the central processing unit 5.
第２図は中央処理装置５を接続するデータ伝送装置の送
信部１−ａおよび受信部１−ｂの構成を示すブロック構
成図である。送信部１−ａはデータ多重化部９とループ
伝送路制御部１１の一部とで構成され、受信部１−ｂは
データ分離化部１０とループ伝送路制御部１１の一部と
で構成される。FIG. 2 is a block diagram showing the configuration of a transmitting section 1-a and a receiving section 1-b of a data transmission device to which the central processing unit 5 is connected. The transmitter 1-a consists of a data multiplexer 9 and a part of the loop transmission line controller 11, and the receiver 1-b consists of the data demultiplexer 10 and a part of the loop transmission line controller 11. be done.
送信部１−ａでは、中央処理袋ｗ５からの送信データａ
と送信要求信号Ｃを送信キャリア識別信号としてデータ
多重化部９で多重変換しチャネル１送信データｇを生成
し、ループ伝送路制御部１１でループ伝送路中の第１チ
ヤネル２０に送信する。In the transmitter 1-a, the transmit data a from the central processing bag w5
The data multiplexer 9 multiplexes and transmits the transmission request signal C as a transmission carrier identification signal to generate channel 1 transmission data g, and the loop transmission path control section 11 transmits it to the first channel 20 in the loop transmission path.
受信部１−ｂでは、ループ伝送路中の第２チヤネル２５
上のチャネル２受信データｊをループ伝送路制御部１１
で分岐し、さらにデータ分離化部１０で受信データｂと
受信キャリア識別信号ｌに分離して中央処理装置５に受
は渡す。In the receiving section 1-b, the second channel 25 in the loop transmission path
The upper channel 2 received data j is sent to the loop transmission path control unit 11.
The data is further separated into received data b and received carrier identification signal l by a data separation unit 10, and the received data is passed to the central processing unit 5.
第３図は端末装置６〜８を接続するデータ伝送装置の送
信部’ｌ−ａ〜４−ａおよび受信部２−ｂ〜４−ｂの構
成を示すブロック構成図である。第１チヤネル２０の受
信部２−ｂ〜４−ｂはデータ分離化部１０とループ伝送
路制御部１１の一部とで構成される。また、第２チヤネ
ル２５の送信部２−ａ〜４−ａはデータ多重化部９と、
フリップフロップ回路１２と、信号選択回路１３と、ア
ンド回路１４と、反転回路１５と、データ分離化部１０
と、ループ伝送路制御部１１の一部とで構成される。FIG. 3 is a block configuration diagram showing the configurations of the transmitting sections 'l-a to 4-a and the receiving sections 2-b to 4-b of the data transmission device connecting the terminal devices 6 to 8. The receiving sections 2-b to 4-b of the first channel 20 are composed of a data demultiplexing section 10 and a part of a loop transmission path control section 11. Further, the transmitting units 2-a to 4-a of the second channel 25 include a data multiplexing unit 9,
Flip-flop circuit 12, signal selection circuit 13, AND circuit 14, inversion circuit 15, and data separation unit 10
and a part of the loop transmission path control section 11.
第１チヤネル２０の受信部２−ｂ〜４−ｂでは、ループ
伝送路中の第１チヤネル２０からのチャネル１受信デー
タｈをループ伝送路制御部１１で分岐し、さらにデータ
分離化部１０で受信データｂと受信キャリア第１識別信
号ｍに分離して多重化装置６．７および８に受は渡す、
第２チヤネル２５の送信部２−ａ〜２−ｂでは、ループ
伝送路中の第２チヤネル２５からのチャネル２送信デー
タｉをループ伝送路制御部１１で分岐し、データ分離化
部１０でチャネル２受信データｊから受信キャリア第２
識別信号ｎを取り出し、反転回路１５を経てアンド回路
１４で受信キャリア第２識別信号が存在しない場合にフ
リップフロップ回路１２に対してクロックｄを出力し、
フリップフロップ回路１２は端末装置からの送信要求が
存在する場合に回路をイネーブルにし、クロックが入力
すると送信キャリア識別信号ｋを出力し、端末装置６．
７および８からの送信要求信号Ｃが存在しない場合に回
路をリセットし、送信キャリア識別信号ｋを出力しない
。一方、端末装置６．７および８からの送信データａと
の送信キャリア識別信号にとをデータ多重化部９で多重
交換し、信号選択回路１３で送信キャリア識別信号が存
在するときにデータ多重化部９からの出力データを選択
出力し、送信キャリア識別信号が存在しないときにチャ
ネル２受信データｊを選択出力し、ループ伝送路制御部
１１でループ伝送路中の第２チヤネル２５に送信する。In the receiving sections 2-b to 4-b of the first channel 20, the channel 1 received data h from the first channel 20 in the loop transmission path is branched by the loop transmission path control section 11, and further by the data separation section 10. Separates into received data b and received carrier first identification signal m and passes to multiplexers 6, 7 and 8,
In the transmitting sections 2-a to 2-b of the second channel 25, the channel 2 transmission data i from the second channel 25 in the loop transmission path is branched by the loop transmission path control section 11, and the data separation section 10 branches the channel 2 transmission data i from the second channel 25 in the loop transmission path. 2 Receive carrier second from received data j
The identification signal n is taken out, passed through the inverting circuit 15, and outputted to the flip-flop circuit 12 by the clock d when the received carrier second identification signal is not present in the AND circuit 14;
The flip-flop circuit 12 enables the circuit when there is a transmission request from the terminal device, outputs a transmission carrier identification signal k when a clock is input, and outputs a transmission carrier identification signal k to the terminal device 6.
When the transmission request signal C from 7 and 8 does not exist, the circuit is reset and the transmission carrier identification signal k is not output. On the other hand, the data multiplexer 9 multiplexes and exchanges the transmission data a from the terminal devices 6.7 and 8 with the transmission carrier identification signal, and the signal selection circuit 13 performs data multiplexing when the transmission carrier identification signal is present. The output data from section 9 is selectively output, and when the transmission carrier identification signal is not present, channel 2 reception data j is selectively output, and the loop transmission path control section 11 transmits it to the second channel 25 in the loop transmission path.
（発明の効果〕
本発明は、以上説明したように、ループ式サイクリック
・ディジタル・データ伝送路に下り専用データ回線と上
り専用データ回線とを持ち、各データ伝送装置が上り専
用データ回線上のキャリア識別信号を受信判定し、他の
データ伝送装置からのキャリア識別信号が存在しない場
合に端末装置からのデータを送信するので、１対Ｎの全
二重通信を実現することができる効果がある。(Effects of the Invention) As explained above, the present invention has a loop-type cyclic digital data transmission line having a downlink-only data line and an uplink-only data line, and each data transmission device has a downlink-only data line and an uplink-only data line. Since the reception of the carrier identification signal is determined and the data from the terminal device is transmitted when there is no carrier identification signal from another data transmission device, it is effective in realizing 1-to-N full-duplex communication. .
第１図は本発明実施例の構成を示すブロック構成図。
第２図は第１図の中央処理装置を接続するデータ伝送装
置の送信部および受信部のブロック構成図。
第３図は端末装置を接続するデータ伝送装置の送信部お
よび受信部のブロック構成図。
１〜４・・・データ伝送装置、５・・・中央処理装置、
６〜８・・・端末装置、９・・・データ多重化部、１０
・・・データ分離化部、１１・・・ループ伝送路制御部
、１２・・・フリップフロップ回路、１３・・・信号選
択回路、１４・・・アンド回路、１５・・・反転回路、
２０・・・下り専用データ回線、２５・・・上り専用デ
ータ回線、ａ・・・送信データ、ｂ・・・受信データ、
Ｃ・・・送信要求信号、ｄ・・・クロック、ｅ・・・ル
ープ伝送路入力データ、ｆ・・・ループ伝送路出力デー
タ、ｇ・・・チャネル１送信データ、ｈ・・・チャネル
ｌ受信データ、ｉ・・・チャネル２送信データ、ｊ・・
・チャネル２受信データ、ｋ・・・送信キャリア識別信
号、ｌ・・・受信キャリア識別信号、ｍ・・・受信キャ
リア第１識別信号、ｎ・・・受信キャリア第２識別信号
。
代理人 弁理士 井 出 直 孝
尖見＋９’ｌの全体講凰
肩 １ 口
実施例の部分購入
Ｍ ２ 図FIG. 1 is a block configuration diagram showing the configuration of an embodiment of the present invention. FIG. 2 is a block configuration diagram of a transmitting section and a receiving section of a data transmission device that connects the central processing unit of FIG. 1. FIG. 3 is a block configuration diagram of a transmitting section and a receiving section of a data transmission device that connects a terminal device. 1 to 4... data transmission device, 5... central processing unit,
6-8...Terminal device, 9...Data multiplexing unit, 10
...Data separation unit, 11...Loop transmission line control unit, 12...Flip-flop circuit, 13...Signal selection circuit, 14...AND circuit, 15...Inversion circuit,
20... Downlink data line, 25... Uplink data line, a... Transmission data, b... Reception data,
C...Transmission request signal, d...Clock, e...Loop transmission line input data, f...Loop transmission line output data, g...Channel 1 transmission data, h...Channel 1 reception data, i...channel 2 transmission data, j...
- Channel 2 received data, k...Transmission carrier identification signal, l...Reception carrier identification signal, m...Reception carrier first identification signal, n...Reception carrier second identification signal. Agent Patent Attorney Nao Ide Takami + 9'l's entire lecture 1 Partial purchase of example M 2 Diagram
Claims (1)
送装置（１）と、 複数の端末装置にそれぞれ接続された第二データ伝送装
置（２、３、４）と、 上記第一および第二データ伝送装置が挿入されたループ
伝送路と を備えたデータ伝送方式において、 上記ループ伝送路は、上記第一データ伝送装置の送信部
から送出され上記第二データ伝送装置の受信部が受信す
るデータ信号が通過する第一回線（２０）および上記第
二データ伝送装置の送信部から送出され上記第一データ
伝送装置の受信部が受信するデータ信号が通過する第二
回線（２５）とを別に備え、 上記第二伝送装置は、データ信号の送出時にキャリア識
別信号を上記第二回線に送出する送出手段、上記第二回
線上のキャリア識別信号の有無を判別する判別手段およ
びこの自装置の判別手段の判別結果に基づき自装置の送
信部からのデータ送出を許可または禁止する制御手段 を備えたことを特徴とするデータ伝送方式。(1) One first data transmission device (1) connected to the central processing unit, second data transmission devices (2, 3, 4) each connected to a plurality of terminal devices, and the first and In a data transmission system comprising a loop transmission path into which a second data transmission device is inserted, the loop transmission path is transmitted from the transmitter of the first data transmission device and received by the receiver of the second data transmission device. Separately from a first line (20) through which data signals pass and a second line (25) through which data signals sent from the transmitter of the second data transmission device and received by the receiver of the first data transmission device pass. The second transmission device comprises a sending means for sending a carrier identification signal to the second line when transmitting a data signal, a determining means for determining the presence or absence of a carrier identification signal on the second line, and a determining device for the own device. A data transmission method characterized by comprising a control means for permitting or prohibiting data transmission from a transmitter of its own device based on a determination result of the means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31310186A JPS63164736A (en) | 1986-12-26 | 1986-12-26 | Data transmission system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31310186A JPS63164736A (en) | 1986-12-26 | 1986-12-26 | Data transmission system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63164736A true JPS63164736A (en) | 1988-07-08 |
Family
ID=18037169
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP31310186A Pending JPS63164736A (en) | 1986-12-26 | 1986-12-26 | Data transmission system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63164736A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02128539A (en) * | 1988-11-09 | 1990-05-16 | Alpine Electron Inc | Method and system for data communication |
-
1986
- 1986-12-26 JP JP31310186A patent/JPS63164736A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02128539A (en) * | 1988-11-09 | 1990-05-16 | Alpine Electron Inc | Method and system for data communication |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPS6041341A (en) | Time division bidirectional transmission system | |
| JPS63164736A (en) | Data transmission system | |
| JPS63208336A (en) | Data transmission system | |
| JPS61228799A (en) | Signal channel communication system | |
| JP2675208B2 (en) | Broadcast communication control method | |
| JPH0338134A (en) | Information transmission equipment for loop type transmission line | |
| JPH03108989A (en) | Data branching trunk | |
| JPS59141849A (en) | Bidirectional catv system | |
| KR0182643B1 (en) | Uni global bus compatible apparatus | |
| JP3028068B2 (en) | Circuit control method for satellite communication system | |
| JP3570899B2 (en) | Data transfer device | |
| JPH08130548A (en) | System and method for time-division multiplex transmission | |
| JPS6316735A (en) | Packet multiple access communication system | |
| JPS60187157A (en) | Information transmission system | |
| JPH04258043A (en) | Common use system for demultiplex and generative relay sections for terminal station equipment | |
| JPH0344140A (en) | Control system for self-routing switch | |
| JPH0117625B2 (en) | ||
| JPS63149932A (en) | Multiplex transmission system | |
| JPH08242298A (en) | Batch multi-address communication system | |
| JPH0451616A (en) | Digital transmission system and repeater | |
| JPH04133542A (en) | Nt1 star connection circuit | |
| JPS60147A (en) | Communication system of control signal | |
| JPS63107345A (en) | Testing system for digital subscriber line | |
| JPH0563762A (en) | Path check system in communication equipment | |
| JPS6031337A (en) | Full duplex communication systen in loop form data transmission system |