JPH04207329A - Terminating resistor loading detecting system for communication network - Google Patents
Terminating resistor loading detecting system for communication networkInfo
- Publication number
- JPH04207329A JPH04207329A JP2329048A JP32904890A JPH04207329A JP H04207329 A JPH04207329 A JP H04207329A JP 2329048 A JP2329048 A JP 2329048A JP 32904890 A JP32904890 A JP 32904890A JP H04207329 A JPH04207329 A JP H04207329A
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- terminating resistor
- communication network
- communication
- terminating
- 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
- 238000004891 communication Methods 0.000 title claims abstract description 48
- 230000005540 biological transmission Effects 0.000 claims abstract description 40
- 238000009434 installation Methods 0.000 claims description 3
- 238000001514 detection method Methods 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 241001024304 Mino Species 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Monitoring And Testing Of Transmission In General (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は通信の際に伝送線路を使用する装置に係り、特
に伝送線路で通信網を形成してその両端な伝送線路の特
性インピーダンスと等しい抵抗値を持つ終端抵抗で終端
する場合の終端抵抗装着検知方式に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device that uses a transmission line for communication, and in particular, the present invention relates to a device that uses a transmission line for communication, and in particular, the present invention relates to a device that uses a transmission line for communication. This invention relates to a terminating resistor installation detection method when terminating with a terminating resistor having a resistance value.
ワードプロセッサやパーソナルコンピュータ等が普及す
るにつれて、これらの装置に通信機能を設は伝送線路で
通信縮髪形成して相互に通信を行う機会が多くなってき
た。そこで、通信網も従来のワークステーションのよう
な敷設工事によって設置された幹線から分岐線を引き出
してそれぞれの装置へ接続する方式ではなく、装置の移
動や新設に伴って一般ユーザーが簡単に伝送線路の引き
回しを自由に行える伝送線路接続方式が望まれる。As word processors, personal computers, and the like have become widespread, opportunities have increased for these devices to be equipped with communication functions and communicate with each other using transmission lines. Therefore, instead of using the conventional workstation system, in which branch lines are drawn out from the main line installed through construction work and connected to each device, general users can easily connect transmission lines when moving or installing new equipment. A transmission line connection method that allows for free routing of lines is desired.
この方式として装置に伝送線路を接続するためのコネク
タを２個設けて、いもづる式に装置間を伝送線路で接続
する方式がある。しかし、電気的反射による波形歪みを
防いで高伝送品質 〆つためには、通信網の両端は伝送
線路の特性インピーダンスと等しい抵抗値を持つ終端抵
抗で終端する必要がある。このとき、専門の保守貝が敷
設工事を行う場合は終端抵抗は確実に装着されるが、一
般ユーザーが伝送線路の引き回し２を行う場合は終端抵
抗の装着を忘才（で装置されないことが多い３仮に、終
端抵抗を装着しなかった時は、電気的反射による波形歪
みが発生し、て高伝送品質を保つことができないため、
通信エラーとなる。７しかし、通信エラーには、送信側
の装置の故障、受信側の装置の故障、伝送線路の短終や
断線及び未接続等要因が多いため、終端抵抗未装着のよ
うな中純であるが頻繁１．：発生しエラなものはユーザ
ーにも判別できることが望まし、い。これによってユー
ザーは通信エラーの要因のうち終端抵抗未装着１．−よ
るものを簡Ｗに対策できる。As this method, there is a method in which two connectors are provided for connecting the transmission lines to the devices, and the devices are connected by the transmission lines in a similar manner. However, in order to prevent waveform distortion due to electrical reflections and achieve high transmission quality, both ends of the communication network must be terminated with a terminating resistor with a resistance value equal to the characteristic impedance of the transmission line. At this time, if a professional maintenance worker performs the installation work, the terminating resistor will be installed reliably, but if a general user is doing the wiring of the transmission line 2, he or she will often forget to install the terminating resistor and will not install the terminating resistor. 3. If a terminating resistor is not installed, waveform distortion will occur due to electrical reflection and high transmission quality cannot be maintained.
A communication error will occur. 7 However, communication errors can be caused by many factors, such as failure of the transmitting side equipment, failure of the receiving side equipment, short termination, disconnection, or disconnection of the transmission line. Frequently 1. :It is desirable that the user can also identify errors that occur. This allows the user to identify one of the causes of communication errors: 1. Not installing a terminating resistor. - It is possible to easily deal with the problem caused by W.
これを解決するため、実願昭６３−６１０８５月では、
伝送線路を接続するだめのコネクタの箇所１こ伝送線路
の接続有無を検知する一ｆ段を設けて接続有の場合は終
端抵抗を装置せず接続叛、の場合は終端抵抗を装着する
ことによって、伝送線路が２本接続し丁いる装ｒでは終
端抵抗が装着さ才Ｉ″４″′伝送線路か１本接続し、て
いる装置ではｙ！：端抵抗が装りさ才（イ１、ため、−
・般コ−ぜ−の千巻類わ喝ことなく白！目的に終端処理
な行う１７式が論しら才１ている。In order to solve this problem, in 1985-61085,
Connector location 1 where the transmission line is connected This is a 1F stage that detects whether or not the transmission line is connected, and if it is connected, no terminating resistor is installed and the connection is changed, and if it is, a terminating resistor is installed. For equipment with two transmission lines connected, a terminating resistor is installed.In equipment with one transmission line connected, a terminating resistor is installed. ：The end resistance is the pretense (I1, Tame, -
・White without making a thousand volumes of general Koze! 17 formulas whose purpose is termination processing are obvious.
［発明か解法り、ようどマる課題〕
しか［、」−記従来技術ては、二１ネクタの箇所に伝送
線路の接続有声：を検知する１段′及び終端抵抗で終端
する手段を名装置勿に２個数けな１．づ才（ばｔ−１゛
、ず、コスト高となる間層があ１〕た。[Problem to be solved by invention or solution] However, in the prior art, a means for terminating with a terminating resistor and a first stage for detecting the presence of connection of a transmission line at the location of the 21 connector has been proposed. Of course there are only two devices.1. There was one interlayer that resulted in high costs.
本発明の目的は、コネクタの箇所に伝送線路の接続有無
を検知する手段及び終端抵抗で終端ずイ・手段を設）づ
ることなく、終端抵抗の装着を確実ｌ−行う方式を提供
することにある１、
し課題をＮ法するための一丁段」
」−２目的を達成Ｊるため番、゛、装置内において、通
信送イ８部の電圧を検出し、て基４：電Ｉ「と比較する
電圧比較ユニッｌ−と、その基準電Ｈ゛と、その比較結
果なユーザーに知らせる表示ユーツ［〜を設Ｎづだ十）
のである１゜
〔代用〕
通仁網内番こ終端抵抗を２個と先、装置ｉし、た時より
も終端抵抗巻１個のみ［Ｉ・）るいは２個とも装着１８
ない時のほうが電圧が高い、上記ミノ＋−」六転二ニッ
トには、一方にこの送信ミルを人力し、他力に終端抵抗
を２個装着り、た時の送信ミルより老干高く設定した基
準電Ｊ十を人力し５、こわにより上記電圧比較ユニット
１４送信電圧と基ｅ電圧の比較を行い比較結果を出力す
る。この比較結果をもとに上記表示ユニットは終端抵抗
装着の有無を・表示する。An object of the present invention is to provide a method for reliably attaching a terminating resistor without installing a means for detecting whether or not a transmission line is connected to a connector and terminating with a terminating resistor. 1. In order to achieve the objective, we detect the voltage of the communication transmission part 8 in the device, and base 4. The voltage comparison unit to be compared with, its reference voltage H, and a display tool that informs the user of the comparison results.
1゜ [Substitute] If you install two terminal resistors in the network, you can install only one terminal resistor winding [I・) or both 18
The voltage is higher when there is no power, so for the above-mentioned Mino+-" six-turn two knit, this transmitting mill is manually operated on one side, and two terminal resistors are installed on the other side, and the voltage is set much higher than the transmitting mill when it is. The reference voltage J0 thus obtained is manually generated, and the voltage comparison unit 14 compares the transmitted voltage with the base e voltage, and outputs the comparison result. Based on this comparison result, the display unit displays whether or not a terminating resistor is installed.
ユーザーはこの表示で終端抵抗が装着さ才１、ていない
ことが確認できるので、終端抵抗の装着忘れが無くなる
。This display allows the user to confirm whether the terminating resistor is attached or not, so there is no chance of forgetting to attach the terminating resistor.
以下本発明の一実施例な第］図、第２図、第３図により
説明する１、第２図は複数台の装置を伝送線路でいもづ
る式に接続してｉｉＩ信網を形成し、た時の図である。The following is an embodiment of the present invention, which will be explained with reference to Figures 1, 2, and 3. In Figures 1 and 2, a plurality of devices are connected in a cascading manner through transmission lines to form an iii communication network. This is a diagram.
１それぞれの装置にはコネクタが２個あり］対の伝送線
路が２本接続されている。但し、通信網の両端の装置【
−は、−力のコネクタには伝送線路が接続され他方のコ
ネクタには終端抵抗が装置される。終端抵抗は伝送線路
の特性インピーダンスと宿しい抵抗値を持ち、こ、ｔｌ
により、電気的反射による波形歪を防いで赴伝送、！ｌ
ｉ＋ ！Ｆｌを保て〕、通信ＩＶｄ、は半２重で、時分
割で受力に送４ｍと個装を♀）う。通信網内の複数の装
置のゝ〕もの１台には本実施例を実現するため手段が内
蔵さ才１ている、この手段は通信網内で１台の装置Ｖ内
蔵されていれば十分であって他の装【に内蔵する必要は
ない。1 Each device has two connectors] Two pairs of transmission lines are connected. However, devices at both ends of the communication network [
-, a transmission line is connected to the - power connector, and a terminating resistor is installed to the other connector. The terminating resistor has the characteristic impedance of the transmission line and the inherent resistance value.
This prevents waveform distortion caused by electrical reflections during transmission. l
i+! [Keep Fl], communication IVd is half-duplex, time-sharing, transmits 4m to the receiving power, and is individually packaged ♀). One of the plurality of devices in the communication network has a built-in means for realizing this embodiment, and it is sufficient that this means is built in one device in the communication network. There is no need to incorporate it into other equipment.
第１図はこの手段を内蔵しまた装置の内部の一部を示し
た図である。通信制御ユニット１は他の装置間との通信
を制御するものである。通（６制御ユニツト１には、自
己の通信データを送信する送信部と他の装置からの通信
データな受信する受信部がある。コネクタ５は伝送線路
な接続するだめのもので装置には２．個ある。通信制御
ユニット１の送信部とコネクタ５とは１対の線て接続さ
才Ｌ ＴＴおり、もう一方のコネクタ５はこの線に並列
に接続さ才ｔており、通信制御ユニット１の受信部もこ
の線に並列に接続、されている。電圧比較ユニット２の
入力部Ａもこの線に並列に接続さねでおり、主用比較ユ
ニット２の入力部Ｆ：は基ｆ？主電圧に接続されており
、電圧比較ユニット２目
入力部への電圧〉入力部Ｂの＠圧
の式か成立し７たならば結契出力部に真の値を出力ｉ
２． 、、表示ユニット３は電圧比較ユニツ）へ２の結
果出力部が真の値ならばＰ端抵抗が未装着の旨の表示を
する。ユーザーはこの表示で終端抵抗が装着さｉｌでい
ないことを確認したならば終端抵抗を装着する６基準電
圧４の電圧は−Ｖｃｅ電圧を抵抗Ｒ１と抵抗Ｒ２で分１
．Ｅするため、
基準電１１４の電圧＝Ｖｃｃ・Ｒ２／（Ｒ，１→Ｒ２）
となり、この電圧を、終端抵抗を２個とも装看シ２ない
時の送信電圧よりは若１−高くなるように抵抗Ｒ１及び
抵抗Ｒ２の飴を設定する。FIG. 1 is a diagram showing a part of the inside of the device incorporating this means. The communication control unit 1 controls communication between other devices. (6) The control unit 1 has a transmitting section that transmits its own communication data and a receiving section that receives communication data from other devices.The connector 5 is for connecting to a transmission line, and the device has two The transmission section of the communication control unit 1 and the connector 5 are connected by a pair of wires, and the other connector 5 is connected in parallel to this wire. The receiving section of the main comparison unit 2 is also connected in parallel to this line.The input section A of the voltage comparison unit 2 is also connected in parallel to this line. It is connected to the voltage, and if the formula of voltage to the second input part of the voltage comparison unit>@pressure of input part B is established and 7, the true value is output to the output part i
2. ,, the display unit 3 displays to the voltage comparison unit (voltage comparison unit) that the P-end resistor is not installed if the result output section 2 is a true value. If the user confirms that the terminating resistor is not installed in this display, attach the terminating resistor.6 The voltage of reference voltage 4 is -Vce voltage divided by resistor R1 and resistor R2.
．． In order to do E, voltage of reference voltage 114 = Vcc・R2/(R,1→R2)
The resistors R1 and R2 are set so that this voltage is 1-1 higher than the transmission voltage when both terminal resistors are not installed.
次に電圧比較ユニット２の人力部Ａの電圧が、終端抵抗
を２個とも装楽し、た時よりも終端抵抗を１個のみ装着
あるいは２個とも装着しない時のほうが電圧が高くなる
ことについて説明する。１第３図は通信制御ユニット］
の送信部の駈動回路を示した図である。１出力■〕と出
力Ｎは差動信号でま５す。Next, it will be explained that the voltage of the human power section A of the voltage comparison unit 2 is higher when only one terminating resistor is installed or when both terminating resistors are installed than when both terminating resistors are installed. do. 1 Figure 3 shows the communication control unit]
FIG. 2 is a diagram showing a cantering circuit of a transmitter. 1 output ■] and output N are differential signals.
出力Ｐの電圧が１Ｉｉｌｈ１７ヘルの時目出力Ｎの電１
「は１、、、、ｏ ｙ、・レベルどなり、出力■）の電
圧がり、ｏＩＩＬ−ヘルの鴎は出力Ｎの電圧はｌｌ ｉ
ｇ ｈレベルとなる、Ｖｃｃ電ＥＥど１〜ランジスタ
Ａ及びトランジスタＣ間の抵抗値を１＜Ｉ・とオる。終
端抵抗の抵抗値（即ち伝送線路の特性インピーダンス値
）をＥノとする。通信データがＨユｇｈ （出力■〕が
ｔｈｉｇｈ）の場合は、トランジスタＡはＯＮ、トラン
ジスタＢはＯＦＦ、トランジスタ（゛はＯＦ Ｆ’、ト
ランジスタＤはＯＮとなる、なお、以下の説明ではトラ
ンジスタＡ−ＤがＯＮ時の電圧降下は無視し２、ＯＦ
Ｆ時の抵抗値は無限大とする。また、通信制御ユニット
１の受信部の入力インピーダンスは無限大、電圧比較ユ
ニット２の人力部Ａおよび入力部Ｂの入力インピーダン
スも無限大とする。通信データがｔ（ｉ ｇ ？で、通
ζ網内に終端抵抗を２個とも装着しまた時の出力Ｐと出
力Ｎ間の電位差Ｖ ｐ ｎ ２は、
Ｖ’ｐ ＋１２＝Ｖｅｅ・Ｉマｚ／（２Ｒｒ＋Ｒｚ）終
端抵抗を１個のみ装着した時の出力Ｉ）と出力Ｎ間の電
位差ｖ ｐ、丁１１は、
Ｖｐｒ＋ １＝Ｖｃｃ−Ｒｚ／ （Ｒｒ＋Ｒ７）終端抵
抗を２個とも装着しない時の出力■）と出力Ｎ間の電位
差Ｖｐｒ＋Ｏは。When the voltage of output P is 1Iilh17hers, the voltage of output N is 1
"is 1,,,,o y, level roars, output ■) voltage increases, oIIL-Hel's seagull output N voltage is ll i
The resistance value between the Vcc voltage EE1, the transistor A, and the transistor C, which is at the gh level, is 1<I. Let E be the resistance value of the terminating resistor (that is, the characteristic impedance value of the transmission line). When the communication data is H (output ■) is high, transistor A is ON, transistor B is OFF, transistor (゛ is OFF F', and transistor D is ON. In the following explanation, transistor A is - Ignoring the voltage drop when D is ON, 2, OF
The resistance value at F is assumed to be infinite. Further, it is assumed that the input impedance of the receiving section of the communication control unit 1 is infinite, and the input impedance of the human power section A and the input section B of the voltage comparison unit 2 is also infinite. When the communication data is t(i g ?) and both terminal resistors are installed in the communication network, the potential difference V p n 2 between the output P and the output N is V'p +12=Vee・I /(2Rr+Rz) The potential difference v p between output I) and output N when only one terminating resistor is installed is Vpr+ 1=Vcc-Rz/ (Rr+R7) When both terminating resistors are not installed The potential difference between output (■) and output N is Vpr+O.
ＶｐｎＯ＝Ｖｅｒ
となり、Ｖ ｐ ｎ Ｏ＞ Ｖ ｐ ｎ １ 〉Ｖｐ
ｎ ２の関係が成１ハ′１ぢ、電圧比較ユニット２の入
力部Ａの電圧ｌｊ：、ｌ端抵抗を２個とも装着した時よ
りも終端抵抗を１個のみ装着おるいは２個とも装着しな
い時のほうが電圧が高くなる。さらに、終端抵抗を１個
のみ装着した時は、装着していない側で電気的反射を発
生し、波形が歪みこれが送信部まで伝搬しすると実際の
出力Ｐと出力Ｎ間の電位差Ｖ ｐ ｎは１−記Ｖ ｐ
ｎ １よりさらに高くなる。終端抵抗な２個とも装着し
７ない時も、通信網の両端で電気的反射が発生し波形が
歪むため実際の出力Ｐと出力Ｎ間の電位差Ｖｐｎは」−
記ＶｐｎＯよりさらに高くなる。また１通信網内のどこ
かで伝送線路が断線または未接続であった場合も終端抵
抗未装着と同様に、出力Ｐと出力Ｎ間の電位差Ｖ ｐ
ｒｉはＶｐｎ２よりも高くなる。上記の基準電圧４はＶ
ｐ ｎ ２． 、よ１）は電圧を若干高く設定す
ればよい、本実施例によれば、実願昭６３−６１０８５
号のような＝１ネクタの箇所に伝送線路の接続有無を検
知する手段及び終端抵抗で終端する手段を通信網内の装
置のコネクタ部毎に設けることなく終端抵抗未装着が簡
単に検知できるため、ユーザーは通信エラーの要因のう
ち終端抵抗未装着によるものを筒型に対策できる効果が
ある。また、伝送線路の断線及び未接続も同様に検知で
きるため、ユーザーは通信エラーの要因のうち伝送線路
の断線及び未接続によるものも簡単に対策できる効果が
ある。VpnO=Ver, and VpnO>Vpn1>Vp
If the relationship of n 2 is satisfied, the voltage lj at input part A of voltage comparison unit 2 is lower than when both l-terminal resistors are installed, or both terminal resistors are installed. The voltage will be higher when not installed. Furthermore, when only one terminating resistor is installed, electrical reflection occurs on the side where it is not installed, distorting the waveform and propagating to the transmitter, the actual potential difference V p n between output P and output N becomes 1-V p
It becomes even higher than n1. Even when both terminating resistors are not installed, electrical reflection occurs at both ends of the communication network and the waveform is distorted, so the actual potential difference Vpn between output P and output N is
It becomes even higher than VpnO. Also, if the transmission line is disconnected or disconnected somewhere within one communication network, the potential difference between output P and output N, V p
ri becomes higher than Vpn2. The reference voltage 4 above is V
p n 2. , 1), the voltage may be set slightly higher.According to this embodiment, Utility Model Application No. 63-61085
This is because it is possible to easily detect whether a terminating resistor is not installed without providing a means for detecting whether a transmission line is connected or not and a means for terminating with a terminating resistor at each connector of the equipment in the communication network at the =1 connector location as shown in the figure. This has the effect of allowing the user to take countermeasures against communication errors caused by not installing a terminating resistor. Furthermore, since disconnection and disconnection of the transmission line can be detected in the same way, the user can easily take measures against communication errors caused by disconnection and disconnection of the transmission line.
本発明によれば、終端抵抗未装着が簡単に検知できるた
め、ユーザーは通信エラーの要因のうちｐ：端抵抗未装
着によるものを簡単に対策できる効果がある。また、伝
送線路の断線及び未接続も同様に検知できるため、ユー
ザーは通信エラーの要因のうち伝送線路の断線及び未接
続によるものも筒部に対策できる効果がある。According to the present invention, since it is possible to easily detect whether a terminal resistor is not installed, the user can easily take countermeasures against communication errors caused by the p: terminal resistor not being installed. In addition, since disconnection and disconnection of the transmission line can be detected in the same way, the user can take countermeasures against communication errors caused by disconnection and disconnection of the transmission line by using the cylinder part.
第１図は本発明の一実施例で装置の内部の一部を示した
図、第２図は複数台の装【を伝送線路でいもづる式に接
続して通信網を形成した峙の図、第３図は第１図におけ
る通信制御ユニット１の送信部の１動回路を示した図で
ある。
１・・・通信制御ユニット、２・・電圧比較ユニット、
３・・・表示ユニット、４・・・基準電圧、５・・コネ
クタ。FIG. 1 is a diagram showing a part of the inside of a device according to an embodiment of the present invention, FIG. FIG. 3 is a diagram showing a one-acting circuit of the transmitting section of the communication control unit 1 in FIG. 1. 1... Communication control unit, 2... Voltage comparison unit,
3...Display unit, 4...Reference voltage, 5...Connector.
Claims (1)
通信網の両端に終端抵抗を装着する通信網において、そ
の装置のうちの１台に通信送信部の電圧を検出して基準
電圧と比較する電圧比較ユニットと、その比較結果をユ
ーザーに知らせる表示ユニットを設け、通信網に終端抵
抗を２個とも装着した時の通信送信部の電圧よりも若干
高めに基準電圧を設定し、通信送信部の電圧が基準電圧
より高いときその結果を表示ユニットに表示することを
特徴とする通信網の終端抵抗装着検知方式。1. In a communication network in which a communication network is formed by connecting devices with a transmission line, and a terminating resistor is installed at both ends of the communication network, one of the devices detects the voltage of the communication transmitter and establishes a standard. A voltage comparison unit that compares the voltage with the voltage and a display unit that informs the user of the comparison results are provided, and the reference voltage is set slightly higher than the voltage of the communication transmitter when both terminating resistors are installed in the communication network. A terminal resistor installation detection method for a communication network characterized by displaying the result on a display unit when the voltage of a communication transmitter is higher than a reference voltage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2329048A JPH04207329A (en) | 1990-11-30 | 1990-11-30 | Terminating resistor loading detecting system for communication network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2329048A JPH04207329A (en) | 1990-11-30 | 1990-11-30 | Terminating resistor loading detecting system for communication network |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04207329A true JPH04207329A (en) | 1992-07-29 |
Family
ID=18217031
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2329048A Pending JPH04207329A (en) | 1990-11-30 | 1990-11-30 | Terminating resistor loading detecting system for communication network |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04207329A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013160763A (en) * | 2012-02-03 | 2013-08-19 | Dr Johannes Heidenhain Gmbh | Position measuring device |
-
1990
- 1990-11-30 JP JP2329048A patent/JPH04207329A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013160763A (en) * | 2012-02-03 | 2013-08-19 | Dr Johannes Heidenhain Gmbh | Position measuring device |
| US10215792B2 (en) | 2012-02-03 | 2019-02-26 | Dr. Johannes Heidenhain Gmbh | Position-measuring device, connectable via a data-transmission channel to transmit data, including a detection unit adapted to detect presence, or non-presence of a pair of lines |
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