JPS60170353A - Data transmitting system - Google Patents
Data transmitting systemInfo
- Publication number
- JPS60170353A JPS60170353A JP2499984A JP2499984A JPS60170353A JP S60170353 A JPS60170353 A JP S60170353A JP 2499984 A JP2499984 A JP 2499984A JP 2499984 A JP2499984 A JP 2499984A JP S60170353 A JPS60170353 A JP S60170353A
- Authority
- JP
- Japan
- Prior art keywords
- communication device
- transmission
- communication
- data
- priority
- 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
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/42—Loop networks
- H04L12/427—Loop networks with decentralised control
- H04L12/433—Loop networks with decentralised control with asynchronous transmission, e.g. token ring, register insertion
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Small-Scale Networks (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の技術分野〕
本発明は、複数の通信装置を伝送路によりループ状に接
続し、一定方向へデータの伝送を行なうデータ通信方式
に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a data communication system in which a plurality of communication devices are connected in a loop through a transmission path and data is transmitted in a fixed direction.
第1図は従来例を示すブロック図でちゃ、各々が送信端
Sおよび受信端Rを有する複数の通信装置CEム〜CH
Dが設けられ、これらの間は伝送路L1〜L4により、
互に隣接する通信装置の送信端Sと受信端Rとが接続さ
れており、全般的に通信装置CEム〜CEDが直列とし
てループ状に接続され、矢印により示す一定方向へデー
タの伝送が行なわれるものとなっている。FIG. 1 is a block diagram showing a conventional example, in which a plurality of communication devices CE to CH each have a transmitting end S and a receiving end R.
D is provided, and transmission lines L1 to L4 are provided between them.
The transmitting end S and the receiving end R of adjacent communication devices are connected, and generally the communication devices CE~CED are connected in series in a loop, and data is transmitted in a fixed direction indicated by the arrow. It has become something that can be done.
しかし、この場合は、例えば通信装置CEAとCEcと
の間においてデータの送受信を行なうものとすれば、通
信装置cEnとCEDとにおいて、各々受信データを自
己宛のものでないと判断のうえ送信する中継動作が行な
われるため、通信装置CIAとCEcとの間におけるデ
ータ伝送に遅延を生じ、総合的な通信所要時間が大とな
る欠点を生ずる。However, in this case, if data is to be sent and received between the communication devices CEA and CEc, the communication devices cEn and CED each determine that the received data is not addressed to them, and then transmit the data. This operation causes a delay in data transmission between the communication devices CIA and CEc, resulting in a drawback that the total communication time becomes long.
本発明は、従来のかかる欠点を根本的に解決する目的を
有し、各通信装置毎に切替器を設け、自己が送信権を有
するときには切替器により送信端を送信側伝送路へ接続
し、送信権を有しないときには切替器により受信側伝送
路を直接送信側伝送路へ接続し、通信に関与しない通信
装置は伝送路中から排除するものとし、更には、送信権
の有無を判断する際、自己の送信優先度と受信した他の
送信優先度とを比較し、自己の送(i優先度が他の送信
優先度に比し同等以下でないときに自己が送信権有りと
判断するものとし、優先度の付与により重要な通信の遅
滞を阻止した極めて効果的な、データ通信方式を提供す
るものである。The present invention has an object of fundamentally solving such drawbacks of the conventional technology, and includes providing a switching device for each communication device, and connecting the transmitting end to the transmitting side transmission path by the switching device when the communication device has the transmission right. When it does not have the right to transmit, the receiving side transmission line shall be directly connected to the transmitting side transmission line by a switch, and communication devices that are not involved in communication shall be excluded from the transmission line. , compares its own transmission priority with the transmission priority of other received transmissions, and determines that it has the right to transmit when its own transmission (i priority) is not equal to or lower than other transmission priorities. , provides an extremely effective data communication method that prevents delays in important communications by assigning priorities.
以下、実施例を示す第2図以降により本発明の詳細な説
明する。Hereinafter, the present invention will be explained in detail with reference to FIG. 2 and subsequent figures showing embodiments.
第2図は、通信装置毎の構成を示すブロック図であシ、
通信装置CFの受信端Rには、光ファイバによる受信側
伝送路LRが光電変換器0/Eを介して接続され、これ
と、電光変換器E10を介する光ファイバの送信側伝送
路L8との間には、切替器SWが挿入されており、通信
装置CEの判断に基づく制御に応じ、自己に送信権が有
るときは通信装置CEの送信端Sを選択し、送信権を有
しないときには受信側伝送路LR側を選択し、送信側伝
送路L8へ接続するものとなっている。FIG. 2 is a block diagram showing the configuration of each communication device.
An optical fiber receiving transmission line LR is connected to the receiving end R of the communication device CF via a photoelectric converter 0/E. A switch SW is inserted in between, and according to the control based on the judgment of the communication device CE, it selects the transmitting end S of the communication device CE when it has the right to transmit, and selects the transmitting end S of the communication device CE when it does not have the right to transmit. The side transmission line LR side is selected and connected to the transmission side transmission line L8.
したがって、切替器SWが受信端R側を選択していれば
、通信装置CEは受信のみが可能となり、伝送路中から
排除され、受信側伝送路LRからの信号がそのiま送信
側伝送路L8へ送信され、通信装置CEの介在による伝
送上の遅延が全く生じないものとなる。Therefore, if the switch SW selects the receiving end R side, the communication device CE is enabled only for reception, is excluded from the transmission path, and the signal from the receiving side transmission path LR is transferred to the transmitting side transmission path. It is transmitted to L8, and there is no transmission delay due to the intervention of the communication device CE.
また、切替器SWが渚信端S側を選択すれば、画伝送路
L R+ L s間が分離され、通信装置CEは送信お
よび受信が自在となる。Furthermore, if the switch SW selects the shore terminal S side, the image transmission paths L R + L s are separated, and the communication device CE becomes free to transmit and receive.
第3図は、第2図の構成に基づく全体のブロック図であ
り、各変換器0/E 、E/’Ot−省略すると共に、
通信状況の推移に応じた切替器SWA〜SW。FIG. 3 is an overall block diagram based on the configuration of FIG. 2, in which each converter 0/E, E/'Ot is omitted, and
Switching devices SWA to SW according to changes in communication status.
の選択状況を(5)〜(E)にわたって示しており、第
4図には、第2図の各段階と対応する各種信号の送受信
状況を示しておる。The selection status is shown in (5) to (E), and FIG. 4 shows the transmission/reception status of various signals corresponding to each stage of FIG. 2.
ここにおいて、まず、第3図(4)および第4図のとお
り、通信装置CEAが送信権を有し、データ信号DT^
を送信端Sから通信装置CEC宛に送信する一方、これ
を受信端Rから受信した通信装置CEcが応答信号AS
cを送信すれば、これが通信装置CIAの受信端Rへ与
えられ、通信装置CEAとCEcとの間においてデータ
通信が行なわれる。Here, first, as shown in FIG. 3 (4) and FIG. 4, the communication device CEA has the transmission right, and the data signal DT^
is sent from the sending end S to the communication device CEC, while the communication device CEc, which received it from the receiving end R, sends a response signal AS.
When c is transmitted, it is given to the receiving end R of the communication device CIA, and data communication is performed between the communication devices CEA and CEc.
ついで、通信装置CIAがデータ信号DTAの送信およ
びデータ信号ASCの受信を終了すると、通信装置CE
Aへ終了信号CDcを送信するだめ、通信装置CEcは
、終了信号CDcの受信に応じ確認信号CUcを送信し
、その直後、切替器SWcを受信端R側とすることによ
り、第3図(B)のとおりになり、通信装置CBs〜C
EDがすべて受信のみの受信モードとなる。Then, when the communication device CIA finishes transmitting the data signal DTA and receiving the data signal ASC, the communication device CE
Instead of transmitting the end signal CDc to A, the communication device CEc transmits a confirmation signal CUc in response to receiving the end signal CDc, and immediately after that, sets the switch SWc to the receiving end R side. ), and the communication devices CBs to C
All EDs are in reception mode, where only reception is possible.
通信装置CIAは、確認信号CUcを受信した後、通信
装置CEcが切替器SWcを(B)の状態とするまでの
所定時間を経てから、第4図のとおり送信権を引継がせ
る旨を示す引継信号CPを送信するため、これが他の通
信装置CEs ” CEo において受信され、通信装
置CEBが送信すべきデータを有するものとすれば、自
己の切替器SWBを制御して送信端S側とし、第3図(
C)の送信モードとなって待機する。After the communication device CIA receives the confirmation signal CUc, after a predetermined period of time has elapsed until the communication device CEc sets the switch SWc to the state (B), the communication device CIA sends a takeover signal indicating that the transmission right is to be taken over as shown in FIG. In order to transmit a signal CP, if this is received by another communication device CEs'' CEo and the communication device CEB has data to be transmitted, it controls its own switch SWB to switch to the sending end S side and Figure 3 (
It enters the transmission mode of C) and waits.
ついで、通信装置CIAは、送信データを有する他の通
信装置が切替器を(C)の状態とするまでの所要時間を
経た後、更に通信装置CEAが送信データを有する場合
は、送信権の要求を示す要求信号CTAに対し、送信デ
ータの優先度を示す優先度コード(1)を付加のうえ、
これらを要求信号CTA (II)として第4図のとお
り送信する。Next, after the time required for another communication device that has the transmission data to set the switch to the state (C), if the communication device CEA also has the transmission data, the communication device CIA requests the transmission right. A priority code (1) indicating the priority of the transmission data is added to the request signal CTA indicating the
These are transmitted as a request signal CTA (II) as shown in FIG.
すると、これが通信装置CEHにおいて受信され、自己
の有する送信データの優先度が(1)であれば、これと
の比較により自己が優先的に送信権を占有すべきものと
判断し、通信装置CEsが優先度コード(1)を付加の
うえ要求信号CTB(1)を第4図のとおり送信するた
め、これが通信装置CEAにおいて受信される。Then, if this is received by the communication device CEH and the priority of the transmission data it owns is (1), it is determined that it should preferentially occupy the transmission right by comparison with this, and the communication device CEs The priority code (1) is added and the request signal CTB (1) is transmitted as shown in FIG. 4, so that it is received by the communication device CEA.
通信装置CEAは、受信した要求信号CTB(1)と自
己の優先度(II)との比較により、送信権を通信装置
CEBへ引継ぐべきものと判断し、要求信号CTB(1
)を第4図のとおりそのまま送信してから、切替器SW
Aを受信端R側とし、第3図(D)の状態とする。The communication device CEA compares the received request signal CTB(1) with its own priority (II), determines that the transmission right should be handed over to the communication device CEB, and transmits the request signal CTB(1).
) as shown in Figure 4, and then switch the switch SW.
A is set to the receiving end R side, and the state shown in FIG. 3(D) is established.
通信装置CEAから転送された要求信号CTB(1)を
通信装置CEBが受信すると、ここにおいて自己に送信
権が付与されたものとの判断がなされ、第4図のとおり
通信装置CEBから宛先アドレスおよび自己アドレスの
コードを付加した応答要求信号Cooが送信されるため
、宛先コードによ多通信装置CEDが指定されれば、こ
れに応じて同装置CEnが切替器SWuを送信端S側と
し、第3図(6)の状態となシ、通信装置CEDが確認
信号CUDを送信するため、通信装置CEaは、この確
認信号を受信してからデータ信号DTaを送信し、デー
タ信号DTBの受信に応じ応答信号ASDの送信を開始
する。When the communication device CEB receives the request signal CTB(1) transferred from the communication device CEA, it is determined that the transmission right has been granted to itself, and as shown in FIG. 4, the communication device CEB sends the destination address and Since the response request signal Coo with its own address code added is transmitted, if the multi-communication device CED is specified by the destination code, the device CEn accordingly sets the switch SWu to the sending end S side and In the state shown in FIG. 3 (6), the communication device CED transmits the confirmation signal CUD, so the communication device CEa transmits the data signal DTa after receiving this confirmation signal, and responds to the reception of the data signal DTB. The transmission of the response signal ASD is started.
したがって、通信装置CEB I CEoとの間におい
て、データ通信が行なわれ、これの終了に応じて以上の
各動作が反復されるものとなり、各通信装置CEA〜C
EDにおいて、高優先度のデータから逐次送信がなされ
るため、重要なデータの送信に遅滞を生じ々いものとな
る。Therefore, data communication is performed with the communication device CEB I CEo, and each of the above operations is repeated in response to the end of the data communication, and each communication device CEA to C
In ED, since data is transmitted sequentially starting from high priority data, delays in transmitting important data are likely to occur.
第5図は、引継信号CTを受信してから以降の通信装置
CEA −CEDによる判断および動作状況を示すフロ
ーチャートであり、プロセッサおよびメモリ等からなる
制御部を備えることにより、これらを実現することがで
きる。FIG. 5 is a flowchart showing the judgment and operation status of the communication device CEA-CED after receiving the takeover signal CT, and these can be realized by providing a control section consisting of a processor, memory, etc. can.
すなわち、引継信号”cp受信? ” 101がYES
と々れば、自己に“送信データあり? ” 102を判
断し、これのYESに応じて切替器SWを制御し“送信
モード設定”103を打力い、要求信号“CT受信?”
104がYESとなれば”自己優先度≦受信優先度?”
105を判断のうえ、これのYESに応じて6受信CT
転送”10@を行なってから切替器SWを制御し、”受
信モード設定°“107を行なう。In other words, the takeover signal "CP reception?" 101 is YES
If so, it determines ``Is there data to be transmitted?'' 102, and in response to YES, controls the switch SW, presses ``Set Transmission Mode'' 103, and issues a request signal ``CT Reception?''
If 104 is YES, “self priority ≦ reception priority?”
After determining 105, if YES to this, 6 reception CT
After performing "transfer" 10@, the switch SW is controlled and "receiving mode setting °" 107 is performed.
一方、ステップ105がNOであれば、自己の優先度が
他の優先度に比し同等以下でなく、自己に送信権が有る
ため、”自己CT送信”111を行ない、要求信号”C
T受佃?°′112のYESに応じ、これが”自己CT
?”113を判断し、これのYESにしたがって”デ
ータ送信”114へ移行する。On the other hand, if step 105 is NO, its own priority is not equal to or lower than other priorities and it has the right to transmit, so it performs "Self CT Send" 111 and sends a request signal "C".
T uke Tsukuda? In response to YES at °'112, this is the "self-CT"
? ``113'' is determined, and in accordance with YES, the process moves to ``data transmission'' 114.
なお、優先度は、各送信データ毎に重要度を示すコード
を付加するものとすればよく、これの等級は(1) 、
(If)のみならず、条件に応じて定めればよい0
このほか、ステップ103まだは111についでタイマ
ーを起動し、これがタイムアツプするまでの一定時間中
にステップ104または112がYESとならなければ
、強制的にステップ107へ移行するものとしてもよく
、データ信号DTの宛先アドレスにより、送信権を有す
る通信装置以外のすべてが同時に指定されたときは、指
定された各通信装置が受信モードを維持するものとして
もよい。Note that the priority may be determined by adding a code indicating the importance to each transmitted data, and the rank of this is (1),
In addition to (If), it can be determined according to the conditions. In addition, a timer is started after step 103 or 111, and if step 104 or 112 does not become YES within a certain period of time until the timer expires. , the process may be forcibly shifted to step 107, and when all communication devices other than those having transmission rights are simultaneously specified by the destination address of the data signal DT, each specified communication device maintains the reception mode. It may also be something to do.
また、第2図においては、切替器SWを光スィッチとし
、各変換器07E、I10を通信装置CE内へ設けても
よく、各伝送路L R+ L 8が電気信号を通ずるも
のであれば、各変換器0/E、E10を省略し、切替器
SWに一般のスイッチを用いればよい等、本発明は種々
の変形が自在である。In addition, in FIG. 2, the switch SW may be an optical switch, and each converter 07E, I10 may be provided in the communication device CE, and if each transmission line L R+ L 8 is one that passes an electric signal, The present invention can be modified in various ways, such as omitting the converters 0/E and E10 and using a general switch as the switch SW.
以上の説明により明らかなとおり本発明によれば、デー
タ伝送上総合的な通信所要時間が短縮される一方、重要
なデータの送信に遅滞を生ぜず、ビル管理設備の各端末
間データ通信等、多数の通信装置がループ状に接続され
る各種のデータ通信において顕著な効果が得られる。As is clear from the above explanation, according to the present invention, the overall communication time required for data transmission is shortened, and there is no delay in transmitting important data, and data communication between terminals of building management equipment, etc. Remarkable effects can be obtained in various data communications in which a large number of communication devices are connected in a loop.
第1図は従来例を示すブロック図、第2図以降は本発明
の実施例を示し、第2図は通信装置毎の構成を示すブロ
ック図、第3図は全体のブロック図、第4図は各種信号
の送受信状況を示す図、第5図は判断および動作状況を
示すフローチャートである。
CE、CE^〜CED ・・・−通信装置、S−・・・
送信端、R11e *−受信端、SW、swA〜swD
・・・・切替器、LR・・自・受信側伝送路、L8・・
・・送信側伝送路、L1〜L4・・e・伝送路。
特許出願人 山武ハネウェル株式会社
代理人 山川数構(ほか2名)
第1図
第2図
第3図
(A)
第3図
(B)
(C)
第3図
(D)
(E)Fig. 1 is a block diagram showing a conventional example, Fig. 2 and subsequent figures show embodiments of the present invention, Fig. 2 is a block diagram showing the configuration of each communication device, Fig. 3 is an overall block diagram, and Fig. 4 5 is a diagram showing the transmission/reception status of various signals, and FIG. 5 is a flowchart showing the judgment and operation status. CE, CE^~CED...-Communication equipment, S-...
Transmission end, R11e *-Reception end, SW, swA to swD
...Switcher, LR...Local/receiving side transmission line, L8...
...Transmission side transmission line, L1 to L4...e transmission line. Patent applicant: Yamatake Honeywell Co., Ltd. Agent: Kazuha Yamakawa (and 2 others) Figure 1 Figure 2 Figure 3 (A) Figure 3 (B) (C) Figure 3 (D) (E)
Claims (2)
状に接続し、一定方向へデータの伝送を行なうデータ伝
送方式において、前記通信装置の受信端へ接続された受
信側伝送路と前記通信装置の送信端とを選択し送信側伝
送路へ接続する切替器を前記各通信装置毎に設け、自己
の通信装置が送@権を有するときに前記切替器により前
記送信端を選択し、前記自己の通信装置が前記送信権を
宿しないときには前記切替器により前記受信側伝送路を
選択することを特徴としたデータ通信方式。(1) In a data transmission method in which a plurality of communication devices are connected in series in a loop through a transmission path and data is transmitted in a fixed direction, a receiving side transmission path connected to a receiving end of the communication device and the communication device A switching device is provided for each of the communication devices to select the sending end and connect it to the sending side transmission line, and when the own communication device has the transmission right, the switching device selects the sending end and connects the sending end to the sending side transmission path. A data communication system characterized in that when the communication device does not have the transmission right, the receiving side transmission path is selected by the switching device.
状に接続し、一定方向へデータの伝送を行なうデータ伝
送方式において、前記通信装置の受信端へ接続された受
信側伝送路と前d己通信装置の送信端とを選択し送信側
伝送路へ接続する切替器を設け、自己の送信優先度と受
信した他の送信優先度とを比較し、前記自己の送信優先
度が前記他の送信優先度に比し同等以下でないときに自
己の、通信装置が送信権布シと判断して前記切替器によ
り前記送信端を選択し、前記比較により前記自己の通信
装置が送信権を有しないと判断したときには前記切替器
により前記受信側伝送路を選択することを特徴としたデ
ータ通信方式。(2) In a data transmission method in which a plurality of communication devices are connected in series in a loop through transmission paths and data is transmitted in a fixed direction, the receiving side transmission path connected to the receiving end of the communication device and the front d A switch is provided to select the transmitting end of the communication device and connect it to the transmitting side transmission path, and compares its own transmission priority with the other received transmission priority, and determines whether the self transmission priority is the same as the other transmission priority. If the priority is not equal to or lower than the priority, the own communication device determines that the transmission right has been granted and selects the transmission end by the switching device, and the comparison determines that the own communication device does not have the transmission right. A data communication system characterized in that when a determination is made, the receiving side transmission path is selected by the switching device.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2499984A JPS60170353A (en) | 1984-02-15 | 1984-02-15 | Data transmitting system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2499984A JPS60170353A (en) | 1984-02-15 | 1984-02-15 | Data transmitting system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS60170353A true JPS60170353A (en) | 1985-09-03 |
Family
ID=12153667
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2499984A Pending JPS60170353A (en) | 1984-02-15 | 1984-02-15 | Data transmitting system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS60170353A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63236438A (en) * | 1987-03-25 | 1988-10-03 | Toshiba Corp | Modem |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5523629A (en) * | 1978-08-07 | 1980-02-20 | Mitsubishi Electric Corp | Loop transmission system |
JPS5559536A (en) * | 1978-10-30 | 1980-05-06 | Hitachi Ltd | Bus priority control system in loop bus network system |
JPS5632854A (en) * | 1979-08-24 | 1981-04-02 | Hitachi Zosen Corp | Control method for occupying right of data highway |
JPS57201353A (en) * | 1981-06-03 | 1982-12-09 | Toshiba Corp | Data transmission system |
JPS58212244A (en) * | 1982-06-03 | 1983-12-09 | Fuji Electric Co Ltd | Controlling system of loop transmission |
-
1984
- 1984-02-15 JP JP2499984A patent/JPS60170353A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5523629A (en) * | 1978-08-07 | 1980-02-20 | Mitsubishi Electric Corp | Loop transmission system |
JPS5559536A (en) * | 1978-10-30 | 1980-05-06 | Hitachi Ltd | Bus priority control system in loop bus network system |
JPS5632854A (en) * | 1979-08-24 | 1981-04-02 | Hitachi Zosen Corp | Control method for occupying right of data highway |
JPS57201353A (en) * | 1981-06-03 | 1982-12-09 | Toshiba Corp | Data transmission system |
JPS58212244A (en) * | 1982-06-03 | 1983-12-09 | Fuji Electric Co Ltd | Controlling system of loop transmission |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63236438A (en) * | 1987-03-25 | 1988-10-03 | Toshiba Corp | Modem |
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