CN100343683C - Method and apparatus for detecting line signal disappearance - Google Patents
Method and apparatus for detecting line signal disappearance Download PDFInfo
- Publication number
- CN100343683C CN100343683C CNB2004100580484A CN200410058048A CN100343683C CN 100343683 C CN100343683 C CN 100343683C CN B2004100580484 A CNB2004100580484 A CN B2004100580484A CN 200410058048 A CN200410058048 A CN 200410058048A CN 100343683 C CN100343683 C CN 100343683C
- Authority
- CN
- China
- Prior art keywords
- signal
- level
- idle
- circuit
- line
- 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.)
- Expired - Fee Related
Links
Images
Abstract
The present invention relates to a method and a device for detecting the disappearance of line signals. The received line signals are detected in a detecting period. When the detected and received line signals are always idle level signals, idle level indicating signals are generated. When the detected and received line signals are non-idle level or level variation signals, the idle level indicating signals are not generated. Before each detecting period is finished, the device detects whether the idle level indicating signals exist. When the idle level indicating signals exist, control signals are output; otherwise the control signals are not output. When the control signals are received, line signal disappearing and indicating signals are not generated. The line signal disappearance detecting device comprises a level converting circuit, a line signal disappearance detecting circuit, a plurality of idle level detecting circuits, a plurality of latch circuits, a concurrent idle detecting circuit and a filtering circuit. The present invention is used for detecting whether the line signals are normally received and whether a detecting line channel is used.
Description
Technical field
The present invention relates to data communication technology field, particularly relate to the detection method and the device of line signal.
Background technology
In data communication network, there are various transmission equipments, each transmission equipment connects by signal line.In order to carry out network management, each transmission equipment all detects at first whether signal is arranged when receiving the signal of other transmission equipment; Testing circuit does not produce the blackout alarm when having signal, so that in time check circuit.
The blackout testing circuit is based on following principle:
One, data were all passed through encoding process before transmission.In order to guarantee that generation sends signal through coding when sending data in signal receiving end correct recovered clock from signal, guaranteeing to send signal by coding constantly has the high-low level variation.
Two, signal through level-conversion circuit, guaranteed that the signal in the cable had enough level amplitudes before being sent to cable, and receiving end can be adjudicated normally.Correspondingly at receiving end level-conversion circuit is arranged also, the level signal that the amplitude that receives is higher is converted to the discernible level signal of device interior.When blackout, level-conversion circuit output fixed level.
Three, whether the blackout testing circuit of signal receiving end comes judgment signal to disappear according to the variation whether high-low level is arranged in the received signal.When in a period of time (for example 10 milliseconds), not finding that level just changes, think that then signal disappears.
In communication facilities is produced, realize the serial equipment of different capabilities different model usually with a jumbo circuit transport module (generally being integrated circuit).When integrated circuit transmittability and actual use are inconsistent, when for example realizing the equipment of transmission 8 road signals with an integrated circuit that can transmit 16 road signals, untapped 8 the tunnel produce blackout alarm because of not receiving signal, it is glittering to produce alarm sound or stand by lamp, can the jamming equipment user to the supervision of these road signals of coming into operation.
Existing solution is as follows:
One, load signal on obsolete path.This method shortcoming is that line is more, the circuit board complexity, especially in device fabrication, in order to reduce production costs and maintenance cost, the general equipment that as far as possible makes a kind of circuit board be applicable to the different capabilities different model relies on to be welded device or to increase the equipment that the method that is provided with realizes the different capabilities different model.So just need on circuit board, increase a lot of switches and line, cause adverse effect for equipment dependability and stability.
Two, the signal encoding of path is not used in cancellation.Because could guarantee that by coding signal constantly has high-low level to change, normally generation blackout alarm, so line signal disappearance testing circuit is stop signal disappearance measuring ability when the cancellation coding all.But along with the function that communication facilities is supported is more and more, the pin resource of integrated circuit and the switch resource on the communication device panel are all more and more nervous, and this method is seldom used now.
Summary of the invention:
In order to solve the above problems, the present invention proposes a kind of method of improved detection line blackout, by detecting the accurate detection of idle level realization to line status.
An object of the present invention is to detect whether normally receive line signal, disappear, then produce line signal disappearance indicator signal, otherwise do not produce line signal disappearance indicator signal if detect line signal.
Another object of the present invention is whether the detection line passage uses, if this passage does not use, does not then produce line signal disappearance indicator signal.
A kind of line signal disappearance detection method of the present invention may further comprise the steps:
When a sense cycle begins, send idle level indicator signal;
In a sense cycle, detect the signal that receives;
Whether the signal of judging this reception busy level or level variation occur, if busy level or level change, just removes idle level indicator signal, otherwise keeps idle level indicator signal.
Judge then whether this sense cycle finishes,, then return the step that judges whether to occur busy level or level variation, finish until this sense cycle if this sense cycle does not finish;
When sense cycle finishes, judged whether idle level indicator signal and turned back to sense cycle to begin;
If judging has idle level indicator signal, then output filtering control signal, otherwise not output filtering control signal directly enter next sense cycle, repeat the step of judging whether this sense cycle finishes;
Judged whether filtered control signal, short of filtered control signal does not just filter the blackout alarm, otherwise carries out trap signal disappearance alarm operation, turns back to then and has judged whether filtered control signal, and repeat its step subsequently.
The present invention also provides a kind of device of detection line blackout, comprises the level-conversion circuit that is used for the conversion line signal, is used to detect the line signal disappearance testing circuit of the output signal of this level-conversion circuit, it is characterized in that also comprising:
A plurality of pull-up resistors, the one end connects direct supply Vcc;
A plurality of idle level sensitive circuits, the input end of each idle level sensitive circuit links to each other with the output terminal of the other end of corresponding pull-up resistor and this level-conversion circuit, is used for the signal and the idle level indicator signal of output of incoming level translation circuit output;
A plurality of latch cicuits, each latch cicuit are connected to corresponding idle level sensitive circuit, are used to receive this free time level indicator signal;
Simultaneously the idle-detection circuit is connected to a plurality of latch cicuits, be used to produce filtered control signal and
Filtering circuit is connected to this while idle-detection circuit and this line signal disappearance testing circuit, is used to produce the blackout alarm after the filtration.
The method and apparatus of detection line blackout of the present invention increases the measuring ability to the line idle level signal on circuit blackout testing circuit, thereby accurately distinguish the user mode and the running status of circuit, whether the circuit that comes into operation can be disappeared by detection signal, can not produce the blackout alarm to the circuit that does not come into operation, make equipment user can not produce maloperation because of the puppet alarm.This method also brings great convenience to device fabrication, because need not consider to the circuit load signal that does not come into operation again or a yard type is set, not only can reduce components and parts and line on the circuit board, reduce the complexity of circuit board, improve reliability, and the circuit board of same category of device different capabilities different model is can be fully compatible, reduces production costs and maintenance cost.
Description of drawings
Fig. 1 is the structural principle synoptic diagram of detection line blackout device of the present invention.
Fig. 2 is the workflow diagram of idle level sensitive circuit in the detection line blackout device of the present invention.
Fig. 3 is the workflow diagram of latch cicuit in the detection line blackout device of the present invention.
Fig. 4 is the workflow diagram of filtering circuit in the detection line blackout device of the present invention.
Fig. 5 is the synoptic diagram of an embodiment of detection line blackout device of the present invention.
Embodiment
Fig. 1 is the structural principle synoptic diagram of detection line blackout device of the present invention.According to the principle of blackout testing circuit, when circuit just often, level-conversion circuit is given testing circuit is the signal that level constantly changes; When line interruption, what level-conversion circuit was given testing circuit is the fixed level signal, and what this moment, general level-conversion circuit was given testing circuit all fixedly is low level.Like this, a kind of state is just arranged, promptly fixedly high level is not utilized, and is called idle level.Suppose that in the present invention idle level is a high level, adopt pull-up resistor to produce.This resistance one termination power Vcc, level-conversion circuit output links to each other with the other end and the idle level sensitive circuit input end of this resistance.When not connecting level-conversion circuit, power Vcc is exported high level by pull-up resistor, promptly idle level.
Under the situation that signalling channel comes into operation, the input end of level-conversion circuit is connected to cable, and output terminal is connected to blackout testing circuit and idle level sensitive circuit.When circuit just often, by the level signal that cable input constantly changes, this signal is through behind level-conversion circuit, its output sends line signal disappearance testing circuit and idle level sensitive circuit simultaneously to.Because line signal disappearance testing circuit receives the level signal of continuous variation, line signal disappearance testing circuit does not produce the blackout alarm; Constantly change because of level signal simultaneously, can not occur idle level all the time in a sense cycle, idle level sensitive circuit does not produce idle level indicator signal yet, and latch cicuit is not received idle level indicator signal, therefore do not produce filtered control signal, do not produce any alarm this moment.Counter is used to produce the sense cycle indicator signal, offers idle level sensitive circuit and latch cicuit respectively.This counter can be provided with separately and also can be arranged in the line signal disappearance testing circuit.
When line interruption, line signal disappears, and level-conversion circuit is sent busy level, generally is low level.Because the signal that does not have level to change, line signal disappearance testing circuit produce the blackout alarm; And idle level sensitive circuit does not detect idle level, do not produce idle level indicator signal, latch cicuit does not produce filtered control signal yet, and the blackout alarm will can not be filtered, thereby export this blackout alarm, offer webmaster or control module (not shown).
When a certain road signalling channel is not used, will disconnect the level-conversion circuit of this passage, the idle level that this moment, pull-up resistor produced sends blackout testing circuit and idle level sensitive circuit simultaneously to.Because this level does not change, line signal disappearance testing circuit produces the blackout alarm; And idle level sensitive circuit detects idle level signal, produce idle level indicator signal and send latch cicuit to, latch cicuit produces filtered control signal, this filtered control signal input filtering circuit is also controlled this filtering circuit the blackout alarm filter of blackout testing circuit output is fallen, i.e. the not output signal alarm that disappears.Like this, detection line coded signal disappearance device just can not produce alarm.This filtering circuit is actually under the control of filtered control signal and plays a part switch.When this paths need use, connect the level-conversion circuit of this paths, then no matter whether circuit has fault, all idle level can not occur, and only this device just produces line signal disappearance alarm when detecting the line signal disappearance.
Fig. 2 is the workflow diagram of idle level sensitive circuit in the detection line blackout device of the present invention.When each sense cycle begins, at first send idle level indicator signal.In sense cycle, detect the signal that receives, judge whether to occur busy level or level and change, if busy level or level change, just remove idle level indicator signal, otherwise keep idle level indicator signal.Judge then whether this sense cycle finishes,, then turn back to sense cycle and begin, otherwise repeat to judge whether to occur busy level or level variation and step subsequently, finish until this sense cycle if this sense cycle finishes.
Fig. 3 is the workflow diagram of latch cicuit in the detection line blackout device of the present invention.According to workflow shown in Figure 2, in a sense cycle, whether there is idle level only when sense cycle finishes, could determine all the time, so judges whether this sense cycle finishes earlier in the workflow of latch cicuit.When sense cycle finishes, check whether idle level indication is arranged.If idle level indication is arranged this moment, then produces filtered control signal; Otherwise do not produce filtered control signal, directly enter next sense cycle, repeat above-mentioned detection step.
Fig. 4 is the workflow diagram of filtering circuit in the detection line blackout device of the present invention.Filtering circuit has at first judged whether filtered control signal, short of filtered control signal, the just not blackout alarm of controlled filter circuit filtering circuit blackout testing circuit generation, otherwise execution filter operation, the blackout alarm that filtering circuit blackout testing circuit produces, i.e. not output signal disappearance alarm.Turn back to then and judged whether filtered control signal, and repeat step subsequently.
Fig. 5 is the synoptic diagram of an embodiment of detection line blackout device of the present invention.The circuit part of dotted line is in the inner realization of integrated circuit RC7017 among the figure.The E1 line signal adopts the HDB3 coding, and idle level is a high level.
The level-conversion circuit of this detection line blackout device is used for the conversion line signal, when the E1 passage come into operation and circuit just often, line signal E1 by cable transmission produces the signal that two level constantly change through this level-conversion circuit, is respectively " level signal 1 after the conversion " and " level signal 2 after the conversion ".When line interruption, line signal E1 disappears, two fixing low levels of this level-conversion circuit output, promptly busy level.
Level signal after two conversions inputs to two idle level sensitive circuits and line signal disappearance testing circuit respectively.Whether the line signal that this line signal disappearance testing circuit is used to detect this level-conversion circuit conversion disappears, when detecting busy level, be line signal and disappear, produce the blackout alarm signal, when detecting the signal of level variation, then do not produce the blackout alarm signal.
One end of two pull-up resistors connects direct supply Vcc, and the other end is connected to this line signal disappearance testing circuit and corresponding idle level sensitive circuit.When the E1 passage does not come into operation, level-conversion circuit is not installed when producing.In this case, two pull-up resistors are exported corresponding two fixed voltages, and promptly idle level after this line signal disappearance testing circuit is received this free time level, will produce the blackout alarm signal.Two idle level sensitive circuits produce idle level indicator signal after receiving this free time level.Two latch cicuits are connected to corresponding idle level sensitive circuit, are used to receive this free time level indicator signal.Simultaneously the idle-detection circuit is connected to the output terminal of two latch cicuits, when two latch cicuits receive idle level indicator signal simultaneously, through producing filtered control signal after the idle-detection processing of circuit simultaneously, otherwise does not produce filtered control signal.Filtering circuit is connected to this while idle-detection circuit and this line signal disappearance testing circuit.This control signal controlled filter circuit filters the blackout alarm signal that this line signal disappearance testing circuit produces.Have only when this line signal disappearance testing circuit and produce the blackout alarm signal and when this while, the idle-detection circuit did not have the output filtering control signal, the line signal disappearance alarm signal after the output filtering, and when receiving this filtered control signal outlet line blackout alarm signal not.
Counter is arranged in the line signal disappearance testing circuit in the present embodiment, and it produces the sense cycle indicator signal and offers idle level sensitive circuit, latch cicuit and line signal disappearance testing circuit.Different line speeds adopts suitable sense cycle.Also can produce idle level in the line signal disappearance pick-up unit of the present invention with pull down resistor.
According to the abovementioned embodiments of the present invention, those skilled in the art can carry out various modifications or variation, and to adapt to the different coding mode, different rates can be provided with different idle level, and these all do not break away from the scope of technical scheme protection of the present invention.
Claims (5)
1. line signal disappearance detection method may further comprise the steps:
When a sense cycle begins, send idle level indicator signal;
In a sense cycle, detect the signal that receives;
Whether the signal of judging this reception busy level or level variation occur, if busy level or level change, just removes idle level indicator signal, otherwise keeps idle level indicator signal;
Judge then whether this sense cycle finishes,, then return the step that judges whether to occur busy level or level variation, finish until this sense cycle if this sense cycle does not finish;
When sense cycle finishes, judged whether that idle level indicator signal and step turn back to sense cycle and begin;
If judging has idle level indicator signal, then output filtering control signal, otherwise not output filtering control signal directly enter next sense cycle, repeat the step of judging whether this sense cycle finishes;
Judged whether filtered control signal, short of filtered control signal does not just filter the blackout alarm, otherwise carries out trap signal disappearance alarm operation, turns back to then and has judged whether filtered control signal, and repeat its step subsequently.
2. according to the line signal disappearance detection method of claim 1, wherein idle level signal is a high level signal, and busy level signal is a low level signal.
3. according to the line signal disappearance detection method of claim 1 or 2, produce the step of sense cycle indicator signal when wherein also being included in beginning.
4. a detection line blackout device comprises the level-conversion circuit that is used for the conversion line signal, is used to detect the line signal disappearance testing circuit of the output signal of this level-conversion circuit, it is characterized in that also comprising:
A plurality of pull-up resistors, the one end connects direct supply Vcc;
A plurality of idle level sensitive circuits, the input end of each idle level sensitive circuit links to each other with the output terminal of the other end of corresponding pull-up resistor and this level-conversion circuit, is used for the signal and the idle level indicator signal of output of incoming level translation circuit output;
A plurality of latch cicuits, each latch cicuit are connected to corresponding idle level sensitive circuit, are used to receive this free time level indicator signal;
Simultaneously the idle-detection circuit is connected to a plurality of latch cicuits, be used to produce filtered control signal and
Filtering circuit is connected to this while idle-detection circuit and this line signal disappearance testing circuit, is used to produce the blackout alarm after the filtration.
5. according to the detection line blackout device of claim 4, it is characterized in that also comprising a counter, be used to produce the sense cycle indicator signal and export to a plurality of idle level sensitive circuits and a plurality of latch cicuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100580484A CN100343683C (en) | 2004-08-11 | 2004-08-11 | Method and apparatus for detecting line signal disappearance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100580484A CN100343683C (en) | 2004-08-11 | 2004-08-11 | Method and apparatus for detecting line signal disappearance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1734274A CN1734274A (en) | 2006-02-15 |
| CN100343683C true CN100343683C (en) | 2007-10-17 |
Family
ID=36076784
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100580484A Expired - Fee Related CN100343683C (en) | 2004-08-11 | 2004-08-11 | Method and apparatus for detecting line signal disappearance |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100343683C (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8607106B2 (en) * | 2010-10-25 | 2013-12-10 | Himax Analogic, Inc. | Channel detection device |
| CN106444485B (en) * | 2016-08-31 | 2020-06-16 | 中车青岛四方机车车辆股份有限公司 | Apparatus for detecting line and method for detecting line |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5563893A (en) * | 1994-02-14 | 1996-10-08 | Hewlett-Packard Company | Integrated level detector |
| CN1302047A (en) * | 1999-12-29 | 2001-07-04 | 上海贝尔有限公司 | Clock signal pulse missing detecting circuit |
| US6377082B1 (en) * | 2000-08-17 | 2002-04-23 | Agere Systems Guardian Corp. | Loss-of-signal detector for clock/data recovery circuits |
| US20020070766A1 (en) * | 2000-12-11 | 2002-06-13 | Therisod Stefano G. | Signal detection scheme for data communication links |
| CN1412961A (en) * | 2001-10-11 | 2003-04-23 | 华为技术有限公司 | Warning circuit for losing real time detection signal and its implement method |
| US6713749B2 (en) * | 2000-10-11 | 2004-03-30 | Vitesse Semiconductor Corporation | Monolithic loss-of-signal detect circuitry |
-
2004
- 2004-08-11 CN CNB2004100580484A patent/CN100343683C/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5563893A (en) * | 1994-02-14 | 1996-10-08 | Hewlett-Packard Company | Integrated level detector |
| CN1302047A (en) * | 1999-12-29 | 2001-07-04 | 上海贝尔有限公司 | Clock signal pulse missing detecting circuit |
| US6377082B1 (en) * | 2000-08-17 | 2002-04-23 | Agere Systems Guardian Corp. | Loss-of-signal detector for clock/data recovery circuits |
| US6713749B2 (en) * | 2000-10-11 | 2004-03-30 | Vitesse Semiconductor Corporation | Monolithic loss-of-signal detect circuitry |
| US20020070766A1 (en) * | 2000-12-11 | 2002-06-13 | Therisod Stefano G. | Signal detection scheme for data communication links |
| CN1412961A (en) * | 2001-10-11 | 2003-04-23 | 华为技术有限公司 | Warning circuit for losing real time detection signal and its implement method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1734274A (en) | 2006-02-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1171398C (en) | Serial data communication between integrated circuits | |
| CN1268096C (en) | Redundant serial bus and method for operating thereof | |
| CN200959622Y (en) | Difference signal transmission line detecting system | |
| CN100343683C (en) | Method and apparatus for detecting line signal disappearance | |
| KR970011839B1 (en) | Data collision detection circuit of lan | |
| CN111049576B (en) | LOS (LOSs of line) alarm method for optical module | |
| CN1713480A (en) | Synchronized switching controller and its control for parallel uninterrupted power supply | |
| CN1505289A (en) | Data signal detection apparatus | |
| CN1148874C (en) | Clock signal pulse missing detecting circuit | |
| CN1859150A (en) | Communication link system and its method with protective function | |
| US4750179A (en) | Selective prevention of bipolar violation detection | |
| US7546518B2 (en) | Received data compensating device | |
| US5285459A (en) | HDB3 code violation detector | |
| US20050025226A1 (en) | Data transmission apparatus and data transmission system | |
| CN210839573U (en) | Optical module LOS alarm system | |
| US6567487B1 (en) | Method for the sampling of biphase coded digital signals | |
| CN1173797A (en) | Bit synchronization circuit and method | |
| CN1184742C (en) | Noise protection circuits | |
| CN114064332A (en) | Clock detection method and device and clock safety system | |
| CN1206824C (en) | Optical-fibre signal interface circuit | |
| CN207382325U (en) | A kind of optical transceiver system | |
| CN219214921U (en) | Signal indication circuit and vehicle | |
| CN101572567B (en) | Auto switching method based on circuit high resistant monitoring | |
| CN114648867B (en) | Remote control signal processing system of propeller, propeller and water-borne carrier | |
| CN116203367A (en) | V2X antenna detection circuit and method and radio frequency communication equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20071017 Termination date: 20170811 |