CN203722657U

CN203722657U - Loop inspection circuit applicable to EOC system

Info

Publication number: CN203722657U
Application number: CN201320852630.2U
Authority: CN
Inventors: 黄凯; 张帆; 张国建; 姚科亮
Original assignee: Wuhan FiberHome Networks Co Ltd
Current assignee: Fiberhome Telecommunication Technologies Co Ltd
Priority date: 2013-12-23
Filing date: 2013-12-23
Publication date: 2014-07-16
Anticipated expiration: 2023-12-23

Abstract

The utility model discloses a loop inspection circuit applicable to an EOC system. The circuit comprises a watchdog chip. The watchdog chip is connected with a switch chip. The switch chip outputs a periodic pulse loop inspection signal or a fixed level signal to the watchdog chip, and the watchdog chip converts the periodic pulse loop inspection signal or the fixed level signal into a high level signal or a low level signal and transmits the difference level signal to an EOC chip for controlling the loop isolation of an EOC terminal. The utility model provides the loop inspection circuit applicable to the EOC system, and the circuit is capable of realizing the loop inspection and release through hardware and achieving the rapid inspection and isolation functions during the terminal looping process, thereby improving the network system reliability and preventing the network faults.

Description

A kind of loop detection circuit that is applicable to EOC system

Technical field

The utility model relates to EOC communication system, is specifically related to a kind of loop detection circuit of the EOC of being applicable to system.

Background technology

Loop detection technique is applied in Ethernet system, conventional all support loop measuring abilities of exchange chip at present, the specific implementation method of loop detection is as follows: exchange chip periodically sends a broadcasting packet for detection of Cheng Huan, and monitor exchange chip all of the port, according to receiving to such an extent that message information judges whether Cheng Huan of system, if there is Cheng Huan, exchange chip will be by interrupting or adopting special signal to report control unit, and cut off the port breaking down, avoid into ring apparatus whole network is impacted.This technology is applicable equally in EOC system.

Transmit Ethernet data system referred to as EOC system by coaxial cable.This system is transmitted by frequency division multiplexing rear ethernet signal modulation and TV signal at same coaxial cable.This technology is simple, and cost is low.Network rebuilding speed is fast.In broadcasting and television network bilateral network retrofit work, be widely used, there is very strong vitality.

EOC system is made up of local side and user terminal, an EOC local side can connect can connect at most 32 or 64 EOC terminal equipments, and at present conventional EOC terminal loop detecting method checks that by the each EOC terminal of local side CPU poll terminal switch chip register determines whether this terminal exists loop.As there is loop, close and have the port of loop or force this terminal deactivation system loop that rolls off the production line issuing configuration.Because network exists uncertainly, in EOC system, just likely occur from ring phenomenon when user misoperation EOC terminal or network failure, can not remove fast as certainly encircled phenomenon, can cause following two class problems:

1, occur that broadcast storm makes network occur congestion collapse, by having influence on all terminals of EOC local side connection, make other user also cannot normally use network, occur communication failure;

2, opened loop detection function as the first line of a couplet device port of EOC system, this Port detecting can be closed this port to loop existence, causes all users under this port normally to surf the Net.

Utility model content

For problems of the prior art, the utility model provides a kind of loop detection circuit of the EOC of being applicable to system, realizes loop detection and releasing by hardware, fast detecting and isolation features while realizing terminal one-tenth ring, and then improve Network System Reliability.

The utility model provides a kind of loop detection circuit of the EOC of being applicable to system, comprise watchdog chip, described watchdog chip connects exchange chip, described exchange chip is to recurrent pulses loop detection signal or the fixed level signal of watchdog chip output, and recurrent pulses loop detection signal or fixed level signal are converted to difference level signal by described watchdog chip, and described difference level signal is outputed in EOC chip, described EOC chip connects exchange chip.

Further, in the time that described exchange chip is exported recurrent pulses loop detection signal to described watchdog chip, described difference level signal is high level signal; In the time that described exchange chip is exported fixed level signal to described watchdog chip, described difference level signal is low level signal.

Further, described high level signal is the level signal of voltage higher than 2V.

Further, described low level signal is the level signal of voltage lower than 0.8V.

Further, described watchdog chip is SGM706, CAT706 or MAX706 model chip.

Further, described exchange chip is RTL8306E model chip.

Further, described EOC chip is AR7411 or AR6400 model chip.

Further, the dog input pin WDI that feeds of described watchdog chip is connected with the output pin LOOPLED of described exchange chip.

Further, the MRX_ERR pin of the output pin WDO of described watchdog chip and the MII interface of described EOC chip is connected.

Further, the reset output pin of described watchdog chip is all connected with the reset input pin of described exchange chip, EOC chip.

The advantage the utlity model has is:

The utility model provides a kind of loop detection circuit of the EOC of being applicable to system, can realize loop detection and releasing by hardware, fast detecting and isolation features while realizing terminal one-tenth ring, and then improve Network System Reliability, avoid occurring network failure.

Brief description of the drawings

Fig. 1 is the structural representation of the loop detection circuit of the EOC system that is applicable to that provides of the utility model.

Embodiment

Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail, so that those skilled in the art can better understand the utility model being implemented, but illustrated embodiment is not as to restriction of the present utility model.

The utility model provides a kind of loop detection circuit of the EOC of being applicable to system, as shown in Figure 1, realize loop detection function by watchdog chip 2 and peripheral circuit thereof as realization body, by exchange chip 1, the recurrent pulses loop detection signal reporting or fixed level signal are sent to watchdog chip 2, described watchdog chip 2 is converted to above-mentioned signal the difference level signal of difference to some extent and is sent to EOC chip 3, and then realizes the level conversion function in loop detection signal process by watchdog chip 2.

The loop detection output pin of described exchange chip 1 connects hello the dog input pin of watchdog chip 2, but, the signal that exchange chip 1 may be exported is two kinds of signals, be recurrent pulses loop detection signal or fixed level signal, that is to say in the time that described network does not become to encircle, the loop detection pin of described exchange chip 1 is output as fixed level signal, and now described watchdog chip 2 judges and does not obtain feeding-dog signal, and now watchdog chip 2 need to be converted into low level signal and export EOC chip 3 to.In the time that described exchange chip 1 detects that network becomes ring, the loop detection pin of described exchange chip 1 is by the recurrent pulses loop detection signal of output fixed cycle, this recurrent pulses loop detection signal meets the requirement of feeding dog pin of watchdog chip 2, watchdog chip 2 gets after feeding-dog signal in judgement, exports high level signal to EOC chip 3.Described high level signal refers generally to the level signal of voltage higher than 2V, and described low level signal refers generally to the level signal of voltage lower than 0.8V.

The difference level signal of house dog output is connected to the MRX_ERR pin of EOC chip 3MII interface, in the time that exchange chip 1 user port becomes ring, what watchdog chip 2 was exported is high level signal, EOC chip 3 will think that the signal receiving from the MRX_ERR pin of MII interface exists mistake, upstream data upwards can not forwarded, cut off upstream data and removed system loop by MII interface to the forwarding of EOC chip 3, isolation is from ring terminal.Meanwhile, local side apparatus still can be inquired about exchange chip 1 state producing from ring terminal by polling mode, and location is Zi encircling terminal alarm to NM server.Staff can be according to this warning information location from ring terminal, and notifies this terminal use to check that terminal network interface connects and remove terminal and recover normal online from ring.In the time that exchange chip 1 user port does not become to encircle, what watchdog chip 2 was exported is low level signal, and EOC chip 3 will think that the signal receiving from the MRX_ERR pin of MII interface does not exist mistake, and upstream data is normally forwarded to EOC chip 3.Between described EOC chip 3 and exchange chip 1, mutually forward upstream data and downlink data by MII interface, in the utility model, only whether become ring to cut off the forwarding of upstream data by loop detection circuit judges, and the forward process of nonintervention downlink data.

Compared with prior art, the loop detection circuit of EOC system that what the utility model provided be applicable to, adopts watchdog chip 2 to realize hardware loop and detects and control, and its circuit is realized simple, becomes written or printed documents low, and productibility is strong.Because carrying out loop detection and completing turn-offs action and time does not need to control by local side CPU, therefore, the utility model in shielding system fast certainly encircle terminal in, also can realize from the location of ring terminal and the problem of ring certainly of final this terminal of releasing.

Exchange chip 1 in the utility model is for having the exchange chip RTL8306E that supports into ring detection output pin; Described EOC chip 3 is AR7411 or AR6400; The microcontroller monitoring chip SGM706 that described watchdog chip 2 is integrated reset, power fail warning and watchdog function.

Described exchange chip 1(RTL8306E) the dog input pin WDI that feeds of loop detection output pin LOOPLED and SGM706 chip be connected, SGM706 chips W DO output pin and EOC chip 3(AR7411 or AR6400) MRX_ERR input pin be connected and realize loop detection function.Meanwhile, by the reset output pin RESET of SGM706 chip is all connected with RTL8306E, AR7411 or AR6400 reset input pin RESET IN, and then realize system power-on reset function.

In the time that the LAN of Ethernet switching chip 1 mouth side does not become to encircle, exchange chip 1(RTL8306E) loop detection pin LOOPLED be output as fixing low level, hello the dog input pin WDI of SGM706 chip is without feeding-dog signal, the output pin WDO of watchdog chip 2 is output as low level, the MII interface energy proper communication that exchange chip 1 is connected with EOC chip 3.In the time there is loop in the LAN of Ethernet switching chip 1 mouth side, exchange chip 1(RTL8306E) loop detection pin LOOPLED output be generally the recurrent pulses loop detection signal of 800ms, the dog input pin WDI that feeds that this signal is output as SGM706 chip provides feeding-dog signal, the output pin WDO of watchdog chip 2 output high level is to AR7411 or AR6400 chip MRX_ERR pin, the MII interface of AR7411 or AR6400 chip will think that the signal receiving is wrong, abandon the upstream data packet that the exchange chip 1 that receives sends, be broken into the function of communicating by letter between ring exchange chip 1 and system thereby realize, avoid out ready-made ring and affect communication service.

Meanwhile, local side apparatus still can be inquired about by polling mode the loop circuit state register of the exchange chip 1 of each terminal, and location is Zi encircling terminal alarm to NM server.Staff can be according to this warning information location from ring terminal, and notifies this terminal use to check that terminal network interface connects and remove terminal and recover normal online from ring.

The above embodiment is only the preferred embodiment for absolutely proving that the utility model is lifted, and protection range of the present utility model is not limited to this.What those skilled in the art did on the utility model basis is equal to alternative or conversion, all within protection range of the present utility model.Protection range of the present utility model is as the criterion with claims.

Claims

1. one kind is applicable to the loop detection circuit of EOC system, it is characterized in that, comprise watchdog chip, described watchdog chip connects exchange chip, described exchange chip is to recurrent pulses loop detection signal or the fixed level signal of watchdog chip output, and recurrent pulses loop detection signal or fixed level signal are converted to difference level signal by described watchdog chip, and described difference level signal is outputed in EOC chip, described EOC chip connects exchange chip.

2. the loop detection circuit that is applicable to EOC system according to claim 1, is characterized in that, in the time that described exchange chip is exported recurrent pulses loop detection signal to described watchdog chip, described difference level signal is high level signal; In the time that described exchange chip is exported fixed level signal to described watchdog chip, described difference level signal is low level signal.

3. the loop detection circuit that is applicable to EOC system according to claim 2, is characterized in that, described high level signal is the level signal of voltage higher than 2V.

4. the loop detection circuit that is applicable to EOC system according to claim 2, is characterized in that, described low level signal is the level signal of voltage lower than 0.8V.

5. according to the loop detection circuit of the EOC system that is applicable to described in claim 3 or 4, it is characterized in that, described watchdog chip is SGM706, CAT706 or MAX706 model chip.

6. the loop detection circuit that is applicable to EOC system according to claim 5, is characterized in that, described exchange chip is RTL8306E model chip.

7. the loop detection circuit that is applicable to EOC system according to claim 6, is characterized in that, described EOC chip is AR7411 or AR6400 model chip.

8. the loop detection circuit that is applicable to EOC system according to claim 7, is characterized in that, the dog input pin WDI that feeds of described watchdog chip is connected with the output pin LOOPLED of described exchange chip.

9. the loop detection circuit that is applicable to EOC system according to claim 8, is characterized in that, the output pin WDO of described watchdog chip is connected with the MRX_ERR pin of the MII interface of described EOC chip.

10. the loop detection circuit that is applicable to EOC system according to claim 9, is characterized in that, the reset output pin of described watchdog chip is all connected with the reset input pin of described exchange chip, EOC chip.