JPH03220834A - Multi-drop data transmission system - Google Patents

Multi-drop data transmission system

Info

Publication number
JPH03220834A
JPH03220834A JP2016814A JP1681490A JPH03220834A JP H03220834 A JPH03220834 A JP H03220834A JP 2016814 A JP2016814 A JP 2016814A JP 1681490 A JP1681490 A JP 1681490A JP H03220834 A JPH03220834 A JP H03220834A
Authority
JP
Japan
Prior art keywords
station
transmission
center station
slave
data
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
Application number
JP2016814A
Other languages
Japanese (ja)
Inventor
Hiroshi Aso
麻生　寛
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.)
NEC Corp
Original Assignee
NEC Corp
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 NEC Corp filed Critical NEC Corp
Priority to JP2016814A priority Critical patent/JPH03220834A/en
Publication of JPH03220834A publication Critical patent/JPH03220834A/en
Pending legal-status Critical Current

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  • Small-Scale Networks (AREA)
  • Synchronisation In Digital Transmission Systems (AREA)

Abstract

PURPOSE:To attain data transmission with an HDLC protocol between a center and a slave station through the use of a multi-drop transmission line by separating an input and output of a token and the HDLC control. CONSTITUTION:In order to give a token for a prescribed time to a slave station 40, a token output circuit 12 of a center station 30 applies multi-drop processing of a token to a slave station 40 and when a token reception circuit 19 of the slave station 40 receives a token for its own station, the token reception circuit 19 outputs a transmission enable signal to an HDLC control circuit 13, an operating mode control circuit 16 and a transmission/reception control circuit 17 to apply data transmission between the center station 30 and the slave station 40 according to the HDLC protocol. When the data transmission for a prescribed time is finished, the slave station 40 uses the token output circuit 12 to returns the token to the center station 30.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明はデータ伝送方式に利用する。[Detailed description of the invention] [Industrial application field] INDUSTRIAL APPLICATION This invention is utilized for a data transmission system.

本発明は、４線式のマルチドロップの伝送路においてセ
ンタ局と複数の子局間のデータ伝送を行うマルチドロッ
プデータ伝送方式に利用する。INDUSTRIAL APPLICATION This invention is utilized for the multi-drop data transmission system which performs data transmission between a center station and a plurality of slave stations on a four-wire multi-drop transmission path.

Ｅ概要〕 本発明は、センタ局とこのセンタ局に同一伝送路を介し
て接続された複数の子局とから構成され、データ伝送を
行うマルチドロップデータ伝送方式データ伝送が行われ
ていないときに、センタ局または特定の子局から「１」
と「０」とを交互にならべた同期パターンを伝送し、そ
れにより受信クロックを抽出し、ＨＤＬＣ手順を用いて
データ伝送を行うようにすることにより、 子局数やデータ量の増加に対してシステムの処理が十分
対応できるようにしたものである。E Overview] The present invention is a multi-drop data transmission system that consists of a center station and a plurality of slave stations connected to the center station via the same transmission path, and that transmits data when data transmission is not being performed. , "1" from the center station or a specific slave station
By transmitting a synchronization pattern consisting of alternating numbers and "0", extracting the reception clock from the synchronization pattern, and transmitting data using the HDLC procedure, it is possible to cope with an increase in the number of slave stations and the amount of data. The system is designed to handle the processing sufficiently.

〔従来の技術〕[Conventional technology]

第２図の本発明の実施例のシステム構成図に示すように
、センタ局３０と複数の子局４０とが共通の伝送路５０
を介して接続され、データ伝送を行う従来のマルチドロ
ップデータ伝送方式として、センタ局３０が子局４０を
ポーリングして、ポーリングされた子局４０がデータを
送信する方式がある。この方式においては、調歩同期方
式をとり、ポーリングデータとユーザデータをソフトウ
ェアで管理している。As shown in the system configuration diagram of the embodiment of the present invention in FIG.
As a conventional multi-drop data transmission system in which the center station 30 polls the slave stations 40 and the polled slave stations 40 transmit data, there is a conventional multi-drop data transmission system in which the center station 30 polls the slave stations 40 and the polled slave stations 40 transmit data. This method uses an asynchronous method, and polling data and user data are managed by software.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

前述したポーリング方式によるマルチドロップデータ伝
送方式では、８ビット単位の調歩同期方式を用いている
ため、伝送効率がＨＤＬＣ（ハイレベルデータリンク）
方式に比べて劣り、端末数およびデータ量の増大に対し
てシステムの要求する処理量を満足できなくなる欠点が
ある。The multi-drop data transmission method using the polling method described above uses an 8-bit start-stop synchronization method, so the transmission efficiency is comparable to that of HDLC (High Level Data Link).
This method has the disadvantage that it cannot satisfy the processing amount required by the system as the number of terminals and amount of data increases.

本発明の目的は、前記の欠点を除去することにより、Ｈ
ＤＬＣ手順によりデータ伝送を可能とし、子局数やデー
タ量の増加に対してシステムの処理が十分に対応できる
マルチドロップデータ伝送方式を提供することにある。The object of the present invention is to eliminate the above-mentioned drawbacks by
It is an object of the present invention to provide a multi-drop data transmission method that enables data transmission using the DLC procedure and allows system processing to sufficiently cope with an increase in the number of slave stations and the amount of data.

〔課題を解決するための手段〕[Means to solve the problem]

本発明は、センタ局と、このセンタ局に同一伝送路を介
して接続された複数の子局とから構成され、データ伝送
を行うマルチドロップデータ伝送方式において、前記セ
ンタ局または特定の子局は、前記子局間または前記セン
タ局と前記子局間で伝送が行われていないときに、「１
」と「０」とを交互にならべた同期パターンを伝送し、
前記子局または前記センタ局は前記同期パターンの変化
点から受信クロックを抽出することを特徴とする。The present invention provides a multi-drop data transmission system that transmits data by comprising a center station and a plurality of slave stations connected to the center station via the same transmission path, in which the center station or a specific slave station , when no transmission is taking place between the slave stations or between the center station and the slave stations, "1"
” and “0” alternately are transmitted,
The slave station or the center station is characterized in that the received clock is extracted from a change point of the synchronization pattern.

また、本発明は、前記センタ局は、子局間伝送を実施す
る場合は送信権を送信し、この送信権を受信した前記子
局は定められた時間内でＨＤＬＣ手順で前記センタ局と
データ送信し、前記子局はデータ伝送終了により送信権
を返却し、前記センタ局は再び前記同期パターンを伝送
することが好ましい。Further, in the present invention, the center station transmits a transmission right when performing inter-slave station transmission, and the slave station that receives the transmission right communicates data with the center station using an HDLC procedure within a predetermined time. It is preferable that the slave station returns the transmission right upon completion of data transmission, and that the center station transmits the synchronization pattern again.

また、本発明は、センタ局と、このセンタ局に同一伝送
路を介して接続された複数の子局とを備えたマルチドロ
ップデータ伝送方式において、前記センタ局および少な
くとも一つの前記子局は、「１」と「０」とを交互にな
らべた同期パターンを発生送信する同期パターン発生手
段と、前記同期パターンを受信し受信クロックを抽出す
る受信クロック抽出手段と、送信権の送信または受信を
行う送信権送受信手段と、ＨＤＬＣ手順にてデータ伝送
を行うデータ伝送手段と、動作モードを選択制御する動
作モード選択制御手段とを含むことを特徴とする。Further, the present invention provides a multi-drop data transmission system including a center station and a plurality of slave stations connected to the center station via the same transmission path, in which the center station and at least one slave station are configured to A synchronization pattern generating means for generating and transmitting a synchronization pattern in which "1" and "0" are arranged alternately, a reception clock extraction means for receiving the synchronization pattern and extracting a reception clock, and transmitting or receiving a transmission right. The present invention is characterized in that it includes a transmission right transmitting/receiving means, a data transmitting means for transmitting data using an HDLC procedure, and an operation mode selection control means for selectively controlling an operation mode.

〔作用〕[Effect]

センタ局と子局とのデータ伝送のための同期は、データ
伝送が行われていないときに伝送される「１」と「０」
とを交互にならべた同期パターンによりその「１」と「
０」との変化により受信クロックを抽出することにより
行われる。そして、データ伝送は送信権を受信した子局
とセンタ局との間でＨＤＬＣ手順に従って行われる。Synchronization for data transmission between the center station and slave stations is performed using "1" and "0" that are transmitted when data is not being transmitted.
"1" and "
This is done by extracting the reception clock based on the change from 0 to 0. Then, data transmission is performed between the slave station that has received the transmission right and the center station according to the HDLC procedure.

すなわち、送信権の入出力とＨＤＬＣ制御とを分離する
ことにより、マルチドロップ伝送路を用いてセンタ局と
子局間でＨＤＬＣ手順でデータ伝送が可能となる。That is, by separating the input/output of transmission rights and HDLC control, it becomes possible to transmit data using the HDLC procedure between the center station and the slave stations using a multi-drop transmission path.

〔実施例〕 以下、本発明の実施例について、図面を参照して説明す
る。[Examples] Examples of the present invention will be described below with reference to the drawings.

第１図は本発明の実施例によるセンタ局および少なくと
も一つの子局（特定の子局）の−例を示すブロック構成
図、および第２図はそのシステムを示すブロック構成国
である。FIG. 1 is a block diagram showing an example of a center station and at least one slave station (specific slave station) according to an embodiment of the present invention, and FIG. 2 is a block diagram showing the country of the system.

本実施例は、センタ局３０と、このセンタ局３０にマル
チドロップ方式の伝送路５０を介して接続された複数の
子局４０とを備えたマルチドロップデータ伝送方式にお
いて、 本発明の特徴とするところの、 センタ局３０および少なくとも一つの子局４０は、「１
」と「０」とを交互にならべた同期パターンを発生送信
する同期パターン発生手段としての１゜０パタ一ン発生
回路１１と、前記同期パターンを受信し受信クロックを
抽出する受信クロック抽出手段としてのりタイミング回
路２１および発振器２２と、送信権の送信または受信を
行う送信権送受信手段としての送信権出力回路１２、送
信権受信回路１９およびスイッチ２０と、ＨＤＬＣ手順
にてデータ伝送を行うデータ伝送手段としてのＨＤＬＣ
制御回路１３と、動作モードを選択制御する動作モード
選択制御手段としてのセレクタ１４、動作モード制御回
路１６およびスイッチ１８とを含んでいる。なお、第１
図において、１５はユーザデータ入出力回路、１７は送
受信制御回路である。This embodiment is a multi-drop data transmission system including a center station 30 and a plurality of slave stations 40 connected to the center station 30 via a multi-drop transmission line 50. However, the center station 30 and at least one slave station 40 are
1°0 pattern generation circuit 11 as a synchronization pattern generating means for generating and transmitting a synchronization pattern in which "0" and "0" are arranged alternately, and a reception clock extraction means for receiving the synchronization pattern and extracting a reception clock. a timing circuit 21 and an oscillator 22; a transmission right output circuit 12 as a transmission right transmitting/receiving means for transmitting or receiving a transmission right; a transmission right receiving circuit 19 and a switch 20; and a data transmission means for transmitting data using an HDLC procedure. HDLC as
It includes a control circuit 13, a selector 14 as an operation mode selection control means for selecting and controlling an operation mode, an operation mode control circuit 16, and a switch 18. In addition, the first
In the figure, 15 is a user data input/output circuit, and 17 is a transmission/reception control circuit.

次に、本実施例の動作について説明する。Next, the operation of this embodiment will be explained.

センタ局３０は、子局４０とデータ伝送をしない場合、
１．０パタ一ン発生回路１１から「１」と「０」とのデ
ータを交互にならべた同期パターンを発生送出し、子局
４゛０ではこの同期パターンでデータの受信クロックを
リタイミング回路２１で抽出する。When the center station 30 does not transmit data with the slave station 40,
1.0 The pattern generation circuit 11 generates and sends out a synchronization pattern in which "1" and "0" data are arranged alternately, and the slave station 4'0 uses this synchronization pattern to control the data reception clock using the retiming circuit. Extract with 21.

センタ局３０は一定時間の送信権を子局４０へ渡すため
、送信権出力回路１２から送信権を子局４０ヘマルチド
ロツプして、子局４０では、送信権受信回路１９により
自局向けの送信権を受信した場合、送信権受信回路１９
から送信可信号がＨＤＬＣ制御回路１３、動作モード制
御回路１６および送受信制御回路１７に対して出力され
て、センタ局３０と子局４０間でＨＤＬＣ手順によるデ
ータ伝送を行う。一定時間のデータ伝送が終了すると、
子局４０は、センタ局３０に送信権出力回路１２により
送信権を返却する。In order to transfer the transmission right for a certain period of time to the slave station 40, the center station 30 multi-drops the transmission right from the transmission right output circuit 12 to the slave station 40, and in the slave station 40, the transmission right receiving circuit 19 receives the transmission right for its own station. , the transmission right receiving circuit 19
A transmission enable signal is output from the HDLC control circuit 13, the operation mode control circuit 16, and the transmission/reception control circuit 17, and data transmission is performed between the center station 30 and the slave stations 40 according to the HDLC procedure. When data transmission ends for a certain period of time,
The slave station 40 returns the transmission right to the center station 30 through the transmission right output circuit 12 .

また、ネットワーク上に定められた特定の子局４０がセ
ンタ局３０と子局４０間の通信を監視してセンタ局３０
と子局４０間でデータ伝送が実施されないとき、その１
．０パタ一ン発生回路１１より「１」、「０２のデータ
を交互にならべた同期パターンを発生送出する。センタ
局３０は、この同期パターンにより子局４０からの受信
データがない場合もデータの受信クロックを抽出する。In addition, a specific slave station 40 defined on the network monitors communication between the center station 30 and slave stations 40, and
When data transmission is not carried out between the terminal and the slave station 40, case 1
．． The 0 pattern generation circuit 11 generates and sends out a synchronization pattern in which "1" and "02" data are arranged alternately.The center station 30 uses this synchronization pattern to generate data even when there is no data received from the slave station 40. Extract the receive clock.

以上の動作において、セレクタ１４、動作モード制御回
路１６およびスイッチ１８は、送信データとして、１．
０同期パターン、送信権、またはデータのいずれを送信
するかの選択制御を行う。In the above operation, the selector 14, the operation mode control circuit 16, and the switch 18 select 1.
Controls selection of which to transmit: 0 synchronization pattern, transmission right, or data.

〔発明の効果〕〔Effect of the invention〕

以上、説明したように、本発明は、送信権の入出力とＨ
ＤＬＣ制御を分離することにより、マルチドロップ伝送
路を用いてセンタと子局間でＨＤＬＣ手順でデータ伝送
が可能となり、子局数やデータ量の増加に対してシステ
ムの処理が十分対応できる効果がある。As explained above, the present invention provides input/output of transmission rights and H
By separating the DLC control, it is possible to transmit data using the HDLC procedure between the center and slave stations using a multi-drop transmission path, and the system has the effect of being able to handle increases in the number of slave stations and the amount of data. be.

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

第１図は本発明の一実施例によるセンタ局および特定の
子局の要部を示すブロックａ戊図。 第２図は本発明の一実施例によるシステムを示すブロッ
ク構成国。 １１・・・１．０パタ一ン発生回路、１２・・・送信権
出力回路、１３・・・ＨＤＬＣ制御回路、１４・・・セ
レクタ、１５・・・ユーザデータ入出力回路、１６・・
・動作モード制御回路、１７・・・送受信制御回路、１
８．２０・・・スイッチ、１９・・・送信権受信回路、
２１・・・リタイミング回路、２２・・・発振器、３０
・・・センタ局、４０・・・子局、５０・・・伝送路。 実施例 （構成ＵｊＪ） 頁、ｔ！例（システム構成） 弔２図FIG. 1 is a block diagram showing essential parts of a center station and a specific slave station according to an embodiment of the present invention. FIG. 2 is a block diagram showing a system according to an embodiment of the present invention. 11... 1.0 pattern generation circuit, 12... Transmission right output circuit, 13... HDLC control circuit, 14... Selector, 15... User data input/output circuit, 16...
・Operation mode control circuit, 17...transmission/reception control circuit, 1
8.20...Switch, 19...Transmission right receiving circuit,
21... Retiming circuit, 22... Oscillator, 30
...Center station, 40...Slave station, 50...Transmission path. Example (configuration UjJ) Page, t! Example (system configuration) Diagram 2

Claims (1)

【特許請求の範囲】 １、センタ局と、このセンタ局に同一伝送路を介して接
続された複数の子局とから構成され、データ伝送を行う
マルチドロップデータ伝送方式において、 前記センタ局または特定の子局は、前記子局間または前
記センタ局と前記子局間で伝送が行われていないときに
、「１」と「０」とを交互にならべた同期パターンを伝
送し、前記子局または前記センタ局は前記同期パターン
の変化点から受信クロックを抽出する ことを特徴とするマルチドロップデータ伝送方式。 ２、前記センタ局は、子局間伝送を実施する場合は送信
権を送信し、この送信権を受信した前記子局は定められ
た時間内でＨＤＬＣ手順で前記センタ局とデータ伝送し
、前記子局はデータ伝送終了により送信権を返却し、前
記センタ局は再び前記同期パターンを伝送する請求項１
記載のマルチドロップデータ伝送方式。 ３、センタ局と、このセンタ局に同一伝送路を介して接
続された複数の子局とを備えたマルチドロップデータ伝
送方式において、 前記センタ局および少なくとも一つの前記子局は、「１
」と「０」とを交互にならべた同期パターンを発生送信
する同期パターン発生手段と、前記同期パターンを受信
し受信クロックを抽出する受信クロック抽出手段と、 送信権の送信または受信を行う送信権送受信手段と、 ＨＤＬＣ手順にてデータ伝送を行うデータ伝送手段と、 動作モードを選択制御する動作モード選択制御手段とを
含む ことを特徴とするマルチドロップデータ伝送方式。[Claims] 1. In a multi-drop data transmission system that transmits data and is composed of a center station and a plurality of slave stations connected to the center station via the same transmission path, the center station or a specific When no transmission is being performed between the slave stations or between the center station and the slave station, the slave station transmits a synchronization pattern in which "1" and "0" are arranged alternately, and the slave station Alternatively, the multi-drop data transmission system is characterized in that the center station extracts a reception clock from a change point of the synchronization pattern. 2. When carrying out inter-slave station transmission, the center station transmits a transmission right, and the slave station that has received this transmission right transmits data with the center station using the HDLC procedure within a predetermined time, and Claim 1: The slave station returns the transmission right upon completion of data transmission, and the center station transmits the synchronization pattern again.
Multidrop data transmission method described. 3. In a multi-drop data transmission system comprising a center station and a plurality of slave stations connected to the center station via the same transmission path, the center station and at least one slave station are
A synchronization pattern generating means for generating and transmitting a synchronization pattern in which "" and "0" are arranged alternately, a reception clock extraction means for receiving the synchronization pattern and extracting a reception clock, and a transmission right for transmitting or receiving a transmission right. A multi-drop data transmission method comprising: a transmitting/receiving means; a data transmitting means for transmitting data using an HDLC procedure; and an operation mode selection control means for selecting and controlling an operation mode.
JP2016814A 1990-01-25 1990-01-25 Multi-drop data transmission system Pending JPH03220834A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2016814A JPH03220834A (en) 1990-01-25 1990-01-25 Multi-drop data transmission system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2016814A JPH03220834A (en) 1990-01-25 1990-01-25 Multi-drop data transmission system

Publications (1)

Publication Number Publication Date
JPH03220834A true JPH03220834A (en) 1991-09-30

Family

ID=11926639

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2016814A Pending JPH03220834A (en) 1990-01-25 1990-01-25 Multi-drop data transmission system

Country Status (1)

Country Link
JP (1) JPH03220834A (en)

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