CN114337734B

CN114337734B - Detection circuit, detection method and chip

Info

Publication number: CN114337734B
Application number: CN202210255143.1A
Authority: CN
Inventors: 房亮; 魏江龙; 应子罡; 曹正; 刘银栋; 张雄波; 于万斌
Original assignee: Beijing Tasson Science and Technology Co Ltd
Current assignee: Beijing Tasson Science and Technology Co Ltd
Priority date: 2022-03-16
Filing date: 2022-03-16
Publication date: 2022-07-29
Anticipated expiration: 2042-03-16
Also published as: CN114337734A

Abstract

The application relates to a detection circuit, a detection method and a chip. The detection circuit includes: the receiving and transmitting circuit comprises a transmitting circuit, an echo cancellation circuit, a switch circuit and a receiving circuit, a first output end of the transmitting circuit and a first input end of the echo cancellation circuit form a first path, a second output end of the transmitting circuit, the switch circuit and a second input end of the echo cancellation circuit form a second path, and the receiving circuit is used for determining whether the differential port is abnormal or not according to an output signal of the echo cancellation circuit when the switch circuit is used for switching on the second path. The detection circuit can avoid adding an additional analog circuit to realize the state detection of the differential port, and can determine whether the differential port is abnormal or not only by controlling the working state of the echo cancellation circuit through the switch circuit, thereby reducing the scale of the detection circuit on the basis of ensuring the state detection function of the differential port.

Description

Detection circuit, detection method and chip

Technical Field

The present application relates to the field of network technologies, and in particular, to a detection circuit, a detection method, and a chip.

Background

Due to the fact that electronic devices in automobiles are more and more at present, the challenge on bandwidth is higher and higher, and calculation and communication of different devices in automobiles can be met by adopting the vehicle-mounted Ethernet technology. In order to ensure that the calculation and communication processes are kept smooth, the interface state of the vehicle-mounted Ethernet needs to be detected in real time, so that the problem of interface connection faults is solved in time according to the detection result, and the interface of the vehicle-mounted Ethernet is kept in a normal connection state.

In the conventional technology, an analog detection circuit is added in an ethernet physical layer interface circuit to detect the interface state of the vehicle-mounted ethernet in real time. However, performing interface state detection in a conventional manner increases the scale of the circuit.

Disclosure of Invention

In view of the above, it is desirable to provide a detection circuit, a detection method and a chip.

In a first aspect, a detection circuit includes: the differential ports between the two transceiver circuits are mutually connected; the receiving and transmitting circuit comprises a transmitting circuit, an echo eliminating circuit, a switching circuit and a receiving circuit; a first channel is formed by a first output end of the transmitting circuit and a first input end of the echo cancellation circuit, and a second channel is formed by a second output end of the transmitting circuit, the switch circuit and a second input end of the echo cancellation circuit;

And the receiving circuit is used for determining whether the differential port is abnormal or not according to the output signal of the echo cancellation circuit when the switch circuit conducts the second channel.

In one embodiment, the receiving circuit is configured to determine whether the differential port is abnormal according to an output signal of the echo cancellation circuit and an output signal of the transmitting circuit when the switching circuit turns on the second path.

In one embodiment, the receiving circuit is configured to determine that one of the differential ports is short when the switching circuit turns on the second path and if it is detected that an output signal of the echo cancellation circuit is equal to a first preset signal; or if the output signal of the echo cancellation circuit is detected to be equal to the second preset signal or the third preset signal, determining that the differential port is abnormal;

the second preset signal is a signal determined according to the first value and the output signal of the transmitting circuit; the third predetermined signal is equal to a first predetermined number of signals comprising the output signal of the transmitting circuit.

In one embodiment, the receiving circuit is further configured to determine an abnormal type of the differential port according to the number of levels included in the output signal of the echo cancellation circuit when the switching circuit opens the second path; the second path is opened by the switching circuit in the case where it is determined that the differential port is abnormal.

In one embodiment, the receiving circuit is specifically configured to determine that the abnormal type of the differential port is that the differential port is short in two paths if the number of detected levels is smaller than the number of levels included in the output signal of the transmitting circuit when the switching circuit disconnects the second path; or if the number of the detected levels is equal to the number of the levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to the fourth preset signal, determining that the abnormal type of the differential port is that the differential port is opened into two paths; or if the number of the detected levels is larger than the number of the levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to a third preset signal, determining that the abnormal type of the differential port is a short normal path in the differential port; or if the number of the detected levels is larger than the number of the levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to a fifth preset signal, determining that the abnormal type of the differential port is a normal one of the differential ports;

wherein the fourth predetermined signal is equal to a signal determined from the second value and the output signal of the transmitting circuit; the fifth preset signal is a second preset number of signals including a sixth preset signal equal to a signal determined according to the third value and the output signal of the transmitting circuit.

In one embodiment, the receiving circuit is further configured to determine that the differential port is normal if it is detected that the output signal of the echo cancellation circuit is equal to a third preset number of signals including the first preset signal when the switching circuit turns on the second path.

In one embodiment, the two transceiver circuits include a first transceiver circuit and a second transceiver circuit, the first transceiver circuit includes a first transmitting circuit, a first echo cancellation circuit, a first receiving circuit and a first switch circuit, and the second transceiver circuit includes a second transmitting circuit, a second echo cancellation circuit, a second receiving circuit and a second switch circuit;

the signal transceiving end of the first transmitting circuit is connected with the first differential port and the first input end of the first echo cancellation circuit, the output end of the first transmitting circuit is connected with the input end of the first switch circuit, the output end of the first switch circuit is connected with the second input end of the first echo cancellation circuit, the output end of the first echo cancellation circuit is connected with the input end of the first receiving circuit, the signal transceiving end of the second transmitting circuit is connected with the second differential port and the first input end of the second echo cancellation circuit, the output end of the second transmitting circuit is connected with the input end of the second switch circuit, the output end of the second switch circuit is connected with the second input end of the second echo cancellation circuit, the output end of the second echo cancellation circuit is connected with the input end of the second receiving circuit, and the first differential port is connected with the second differential port.

In one embodiment, the first transceiver circuit further comprises a first dc blocking circuit, and the second transceiver circuit further comprises a second dc blocking circuit;

the input end of the first blocking circuit is connected with the output end of the first transmitting circuit, and the input end of the second blocking circuit is connected with the output end of the second transmitting circuit.

In one embodiment, the signal transceiving terminal of the first transmitting circuit forms a third path with the first input terminal of the first echo cancellation circuit, the output terminal of the first transmitting circuit, the first switch circuit and the second input terminal of the first echo cancellation circuit form a fourth path, the signal transceiving terminal of the second transmitting circuit forms a fifth path with the first input terminal of the second echo cancellation circuit, and the output terminal of the second transmitting circuit, the second switch circuit and the second input terminal of the second echo cancellation circuit form a sixth path;

the first receiving circuit is used for determining whether the first differential port is abnormal or not according to an output signal of the first echo cancellation circuit when the fifth path is conducted by the first switch circuit;

and the second receiving circuit is used for determining whether the second differential port is abnormal or not according to the output signal of the second echo cancellation circuit when the sixth channel is conducted by the second switching circuit.

In a second aspect, a method of detection, the method comprising:

acquiring a first output signal of a transmitting circuit;

controlling the conducting state of the switch circuit;

and if the switch circuit is conducted, determining whether the differential port is abnormal or not according to the first output signal and the second output signal of the echo cancellation circuit.

In one embodiment, if the switch circuit is turned on, determining whether the differential port is abnormal according to the first output signal and the second output signal of the echo cancellation circuit includes:

if the conducting state of the switch circuit is a high level state, judging whether a second output signal of the echo cancellation circuit is the same as a first preset signal or not;

if the second output signal of the echo cancellation circuit is the same as the first preset signal, determining that one of the differential ports is short;

if the second output signal of the echo cancellation circuit is different from the first preset signal, judging whether the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal;

if the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal, determining that the differential port is abnormal;

the second preset signal is a signal determined according to the first value and the first output signal of the transmitting circuit; the third predetermined signal is equal to a first predetermined number of signals comprising the first output signal of the transmitting circuit.

In one embodiment, if the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal, determining that the differential port is abnormal includes:

if the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal, controlling the conduction state of the switch circuit to be a low level state;

and determining the abnormal type of the differential port according to the level number included in the first output signal and the level number included in the second output signal.

In one embodiment, determining the anomaly type of the differential port according to the number of levels included in the first output signal and the number of levels included in the second output signal includes:

if the number of the levels included in the second output signal is smaller than the number of the levels included in the first output signal, determining that the abnormal type of the differential port is that the differential port is short in two paths;

if the number of levels included in the second output signal is equal to the number of levels included in the first output signal and the output signal of the echo cancellation circuit is equal to a fourth preset signal, determining that the abnormal type of the differential port is that the differential port is opened in two ways;

if the number of levels included in the second output signal is larger than that included in the first output signal and the second output signal is equal to a third preset signal, determining that the abnormal type of the differential port is a short normal path in the differential port;

If the number of levels included in the second output signal is larger than that included in the first output signal and the second output signal is equal to a fifth preset signal, determining that the abnormal type of the differential port is a normal one of the differential ports;

The detection circuit, the detection method and the chip comprise: the receiving and transmitting circuit comprises a transmitting circuit, an echo cancellation circuit, a switch circuit and a receiving circuit, wherein a first output end of the transmitting circuit and a first input end of the echo cancellation circuit form a first path, a second output end of the transmitting circuit, the switch circuit and a second input end of the echo cancellation circuit form a second path, and the receiving circuit is used for determining whether the differential port is abnormal or not according to an output signal of the echo cancellation circuit when the switch circuit conducts the second path; the detection circuit can avoid adding an additional analog circuit to realize the state detection of the differential port, and can determine whether the differential port is abnormal or not only by controlling the working state of the echo cancellation circuit through the switch circuit, thereby reducing the scale of the detection circuit on the basis of ensuring the state detection function of the differential port.

Drawings

FIG. 1 is a schematic diagram of an embodiment of a detection circuit;

FIG. 2 is a schematic diagram of a detection circuit according to another embodiment;

FIG. 3 is a schematic diagram of a specific structure of the detection circuit in the embodiment of FIG. 1;

FIG. 4 is a schematic diagram of a specific structure of the detection circuit in the embodiment of FIG. 2;

fig. 5 is a diagram illustrating a structure of 6 status detection results corresponding to a first differential port 1 and a first differential port 2 in a first transceiver circuit in an embodiment;

FIG. 6 is a schematic flow chart of a detection method in one embodiment;

FIG. 7 is a flow chart illustrating the process of determining whether a differential port is abnormal according to another embodiment;

FIG. 8 is a flow diagram illustrating a process for determining differential port anomalies in accordance with another embodiment;

FIG. 9 is a flowchart illustrating a method for determining an exception type for a differential port according to another embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

The detection circuit provided by the application can be applied to a chip, a field programmable gate array chip or other hardware circuit devices for detecting the state of the Ethernet port. In this embodiment, the detection circuit and the detection method are described by taking the vehicle-mounted ethernet port as an example, and therefore, in this embodiment, the chip may be a vehicle-mounted ethernet chip.

Fig. 1 is a schematic structural diagram of a detection circuit according to an embodiment, where the detection circuit includes: the differential ports between the two transceiver circuits are connected with each other; the receiving and transmitting circuit comprises a transmitting circuit, an echo eliminating circuit, a switching circuit and a receiving circuit; a first path is formed by a first output end of the transmitting circuit and a first input end of the echo cancellation circuit, and a second path is formed by a second output end of the transmitting circuit, an output end of the switch circuit and a second input end of the echo cancellation circuit;

Specifically, the detection circuit may include two transceiver circuits, each of which may detect the state of its respective differential port, and only one transceiver circuit is shown in fig. 1. In order to reduce the number of external cables, in the detection circuit, the differential ports between the two transceiver circuits can be connected with each other through the differential twisted pair, that is, the differential twisted pair has the function of sending and receiving signals at the same time, and meanwhile, the echo cancellation circuit in the transceiver circuits prevents the echo of the transmission signal from interfering the output signal of the other transceiver circuit to cause error codes.

It should be noted that the transmitting circuit in the transceiver circuit may include a plurality of input terminals and a plurality of output terminals, and the functions of each input terminal and each output terminal may be different. The echo cancellation circuitry in the transceiver circuitry may comprise a plurality of inputs and an output, and the functions of the inputs and outputs may be different. The first output terminal of the transmitting circuit and the first input terminal of the echo cancellation circuit form a first path, that is, the output signal of the transmitting circuit can be transmitted to the echo cancellation circuit through the first path. The signals output by the first output terminal and the second output terminal of the transmission signal may be the same. The output signal of the transmitting circuit can be two paths of differential signals, and the phase difference between the two paths of differential signals is 180 degrees. Meanwhile, the output signal of the echo cancellation circuit is also two paths of differential signals.

Meanwhile, the switching circuit in the transceiver circuit may include an input terminal and an output terminal, and functions of the input terminal and the output terminal may be different. The receiving circuit in the transceiving circuit may comprise an input. The second output end of the transmitting circuit, the switch circuit and the second input end of the echo cancellation circuit form a second path, that is, when the switch circuit is switched on, the output signal of the transmitting circuit can be transmitted to the echo cancellation circuit from the second path through the switch circuit; when the switch circuit is not conducted, the output signal of the transmitting circuit cannot be transmitted to the echo cancellation circuit from the second path through the switch circuit, and at the moment, the echo cancellation circuit can only receive the output signal of the transmitting circuit transmitted from the first path. The output signal output by the first output terminal of the transmitting circuit may be the same as the output signal output by the second output terminal of the transmitting circuit, that is, the signals received by the first input terminal and the second input terminal of the echo cancellation circuit may be equal when the switch circuit is turned on. Switching on of the switching circuit may be understood as switching off of the switching circuit, in which case the switching circuit may correspond to a high state; a non-conducting of the switching circuit may be understood as a non-closed switching circuit, in which case the switching circuit may correspond to a low state.

It will be appreciated that the conductive state of the switching circuit may control the operating state of the echo cancellation circuit. When the switching circuit is switched on, the echo cancellation circuit works; when the switch circuit is not conducted, the echo cancellation circuit does not work, and at the moment, the echo cancellation circuit only receives and transmits signals and does not perform other processing.

In this embodiment, when the switch circuit turns on the second path, the receiving circuit may determine whether the differential port is abnormal according to the output signal of the echo cancellation circuit. Meanwhile, when the switch circuit is conducted to the second channel, the receiving circuit can also determine that the differential port is in a normal state according to the output signal of the echo cancellation circuit. The abnormal state of the differential port can be states of a short two-way differential port, an open two-way differential port, a short one-way open one-way differential port, a normal one-way short one-way differential port, a normal one-way open one-way differential port and the like. The detection circuit can avoid adding an additional analog circuit to realize the state detection of the differential port, and only adjusts the working state of the echo cancellation circuit through the switch circuit, so that signals received by the receiving circuit of the differential port in different states have level uniqueness, and the state detection of the Ethernet differential port is realized.

The detection circuit comprises two transceiver circuits, wherein differential ports between the two transceiver circuits are connected with each other, the transceiver circuits comprise a transmitting circuit, an echo cancellation circuit, a switch circuit and a receiving circuit, a first output end of the transmitting circuit and a first input end of the echo cancellation circuit form a first path, a second output end of the transmitting circuit, the switch circuit and a second input end of the echo cancellation circuit form a second path, and the receiving circuit is used for determining whether the differential ports are abnormal or not according to output signals of the echo cancellation circuit when the switch circuit conducts the second path; the detection circuit can avoid adding an additional analog circuit to realize the state detection of the differential port, only controls the working state of the echo cancellation circuit through the switch circuit to control the echo cancellation circuit to process the received signal so as to obtain the output signal of the echo cancellation circuit, and further determines whether the differential port is abnormal according to the output signal of the echo cancellation circuit, thereby reducing the scale of the detection circuit on the basis of ensuring the detection function of the state of the differential port, saving the cost of the detection circuit, reducing the complexity of the detection circuit and simplifying the detection mode.

As one embodiment, the receiving circuit in the detection circuit is configured to determine whether the differential port is abnormal according to an output signal of the echo cancellation circuit and an output signal of the transmitting circuit when the switch circuit turns on the second path.

Specifically, the switch circuit in the detection circuit is closed, the switch circuit conducts the second path, so that the echo cancellation circuit operates, at this time, the echo cancellation circuit may receive an output signal of the transmission circuit, an output signal of the switch circuit, and an output signal of another transceiver circuit, and process these signals to obtain an output signal RX of the echo cancellation circuit, that is, RX may be equal to TRX-TX, where TRX represents a mixed signal of the output signal of the transmission circuit and an output signal of another transceiver circuit, and TX represents an output signal of the switch circuit. The receiving circuit in the detection circuit may receive the output signal of the echo cancellation circuit, and perform operation processing, comparison processing, analysis processing, and/or conversion processing on the output signal of the echo cancellation circuit and the output signal of the transmitting circuit, and so on, to determine whether the differential port is abnormal.

The receiving circuit in the detection circuit is used for determining that one path is short in the differential port if the output signal of the echo cancellation circuit is detected to be equal to a first preset signal when the second path is conducted by the switch circuit; or if the output signal of the echo cancellation circuit is detected to be equal to a second preset signal or a third preset signal, determining that the differential port is abnormal, wherein the second preset signal is a signal determined according to the first value and the output signal of the transmitting circuit; the third predetermined signal is equal to a first predetermined number of signals comprising the output signal of the transmitting circuit.

It should be noted that, when the switch circuit turns on the second path to operate the echo cancellation circuit, the echo cancellation circuit may receive the output signal of the transmitting circuit, the output signal of the switch circuit, and the output signal of the other transceiver circuit, and process these signals to obtain an output signal RX of the echo cancellation circuit, that is, RX may be equal to TRX-TX, where TRX represents a mixed signal of the output signal of the transmitting circuit and the output signal of the other transceiver circuit, and TX represents the output signal of the switch circuit. In this case, the receiving circuit in the detection circuit may receive an output signal of the echo cancellation circuit, and when it is detected that the output signal of the echo cancellation circuit is equal to the first preset signal, it may be determined that one short is opened in the differential port; alternatively, when it is detected that the output signal of the echo cancellation circuit is equal to the second preset signal or equal to the third preset signal, it may be determined that the differential port is abnormal. The first preset signal may be a single-level signal, that is, a high-level signal 1 or a low-level signal 0, and in this embodiment, the first preset signal is a low-level signal 0. Alternatively, if the output signal of the transmitting circuit is (-1.5, 1.5), the second predetermined signal may be equal to a signal determined according to the first value and the output signal of the transmitting circuit; the first value may be any constant other than 0, but in the present embodiment, the first value may be equal to 2, that is, the second preset signal may be equal to (-3, 3). Optionally, the first preset number may be any constant other than 0, but is not equal to the first value, and in this embodiment, the first preset number may be equal to 6, so that the third preset signal may be equal to 6 signals including the output signal (-1.5, 1.5) of the transmitting circuit, and it is also understood that the remaining 4 signals other than-1.5 and 1.5 in the third preset signal may be level signals.

Meanwhile, the receiving circuit in the detection circuit is also used for determining the abnormal type of the differential port according to the level number included in the output signal of the echo cancellation circuit when the switch circuit disconnects the second path; the second path is opened by the switching circuit in the event that the differential port is determined to be abnormal. When the switch circuit turns on the second path, the output signal RX of the echo cancellation circuit may be equal to TRX-TX, where TRX represents a mixed signal of the output signals TX of the two transmitting circuits in the two transceiver circuits, and at this time, the output signal RX of the echo cancellation circuit may be understood as a received output signal of the other transmitting circuit. When the switching circuit is conducting the second path, the output signal RX of the echo cancellation circuit may be equal to TRX-TX, at which time the output signal TX of the transmitting circuit in the transceiver circuit is currently 0, which indicates that the echo cancellation circuit is not operating and only has signal receiving and transmitting functions.

Optionally, when the switch circuit turns on the second path to operate the echo cancellation circuit, the echo cancellation circuit may receive an output signal of the transmitting circuit, an output signal of the switch circuit, and an output signal of the transceiver circuit, and process these signals to obtain an output signal RX of the echo cancellation circuit, where RX may be equal to TRX-TX, where TRX represents a mixed signal of the output signal of the transmitting circuit and an output signal of another transceiver circuit, and TX represents the output signal of the switch circuit. In this case, the receiving circuit in the detection circuit may receive the number of levels included in the output signal of the echo cancellation circuit, and determine the abnormality type of the differential port. Illustratively, if the output signal of the echo cancellation circuit is 0, the number of levels included in the output signal of the echo cancellation circuit is 1; if the output signal of the echo cancellation circuit is (-1.5, 1.5), the number of levels included in the output signal of the echo cancellation circuit is 2; if the output signal of the echo cancellation circuit is (-1.5, 0, 1.5), the output signal of the echo cancellation circuit includes-1.5, 0, and 1.5 of three different levels, in which case the number of levels included in the output signal of the echo cancellation circuit is 3.

The detection circuit can control the working state of the echo cancellation circuit through the switch circuit to control the echo cancellation circuit to process the received signal so as to obtain the output signal of the echo cancellation circuit, and further the receiving circuit determines whether the differential port is abnormal according to the output signal of the echo cancellation circuit and the output signal of the transmitting circuit.

As one embodiment, the receiving circuit in the detection circuit is specifically configured to determine that the abnormal type of the differential port is two short paths of the differential port if the detected number of levels is smaller than the number of levels included in the output signal of the transmitting circuit when the switching circuit disconnects the second path; or if the number of the detected levels is equal to the number of the levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to the fourth preset signal, determining that the abnormal type of the differential port is that the differential port is opened into two paths; or if the number of the detected levels is larger than the number of the levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to a third preset signal, determining that the abnormal type of the differential port is a short normal path in the differential port; or if the number of the detected levels is larger than the number of the levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to a fifth preset signal, determining that the abnormal type of the differential port is a normal one of the differential ports;

Specifically, after the receiving circuit in the detection circuit detects that the differential port is abnormal, the switching circuit in the detection circuit may be turned off, that is, the switching circuit turns off the second path, so that the echo cancellation circuit does not operate, and the receiving circuit continues to detect the abnormal type of the differential port. The switch circuit in the open detection circuit may be understood as the switch circuit not being closed.

It should be noted that, after the switch circuit in the detection circuit is turned off, the echo cancellation circuit may receive the output signal of the transmitting circuit and the output signal of the transceiver circuit, and process these signals to obtain an output signal RX of the echo cancellation circuit, where RX may be equal to TRX-TX, where TRX represents a mixed signal of the output signal of the transmitting circuit and the output signal of another transceiver circuit, and TX represents the output signal of the switch circuit. In this embodiment, RX may also be equal to RXP1-RXn 1.

Further, the receiving circuit continues to determine whether the number of levels included in the output signal of the echo cancellation circuit is smaller than the number of levels included in the output signal of the transmitting circuit, and if it is determined that the number of levels included in the output signal of the echo cancellation circuit is smaller than the number of levels included in the output signal of the transmitting circuit, it may be determined that the abnormal type of the differential port is that the differential port is short in two ways.

Or, the receiving circuit may determine that the differential port is opened in two ways if it is determined that the number of levels included in the output signal of the echo cancellation circuit is equal to the number of levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to the fourth preset signal. Optionally, the fourth preset signal is equal to a signal determined according to the second value and an output signal of the transmitting circuit; the second value may be any constant other than 0, but in this embodiment the first value may be equal to 4, i.e. the second predetermined signal may be equal to (-6, 6).

Or, the receiving circuit continues to determine whether the number of levels included in the output signal of the echo cancellation circuit is greater than the number of levels included in the output signal of the transmitting circuit, and determines whether the output signal of the echo cancellation circuit is equal to a third preset signal, and if it is determined that the number of levels is greater than the number of levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to the third preset signal, it may be determined that the abnormal type of the differential port is the normal one of the short path in the differential port. Alternatively, the third preset signal may be equal to a first preset number of signals comprising the output signal of the transmitting circuit. The first preset number may be any constant other than 0, but is not equal to the first value, and in this embodiment, the first preset number may be equal to 6, so that the third preset signal may be equal to 6 signals including the output signal (-1.5, 1.5) of the transmitting circuit, and it is also understood that the remaining 4 signals other than-1.5 and 1.5 in the third preset signal may be level signals.

Or, the receiving circuit continues to determine whether the number of levels included in the output signal of the echo cancellation circuit is greater than the number of levels included in the output signal of the transmitting circuit, and determines whether the output signal of the echo cancellation circuit is equal to a fifth preset signal, and if it is determined that the number of levels included in the output signal of the echo cancellation circuit is greater than the number of levels included in the output signal of the transmitting circuit and whether the output signal of the echo cancellation circuit is equal to the fifth preset signal, it may be determined that the abnormal type of the differential port is a normal one of the differential ports.

Meanwhile, the receiving circuit in the detection circuit is further configured to determine that the differential port is normal if it is detected that the output signal of the echo cancellation circuit is equal to a third preset number of signals including the first preset signal when the switching circuit turns on the second path.

Further, as shown in fig. 2, a circuit structure of another detection circuit is shown, and the detection circuit includes: the differential ports between the two transceiver circuits are connected with each other; the receiving and transmitting circuit comprises a transmitting circuit, a blocking capacitor, an echo eliminating circuit, a switching circuit and a receiving circuit; a first output end of the transmitting circuit and a first input end of the echo cancellation circuit form a first path, a second output end of the transmitting circuit, an output end of the switch circuit and a second input end of the echo cancellation circuit form a second path, and the blocking capacitor is connected with the output end of the transmitting circuit and the first input end of the echo cancellation circuit;

the receiving circuit is used for determining whether the differential port is abnormal or not according to the output signal of the echo cancellation circuit when the switch circuit conducts the second channel; and the DC blocking capacitor is used for preventing the static operating point of the differential port of the transmitting circuit from shifting so as to generate signal distortion.

The detection circuit can control the echo cancellation circuit to be out of operation through the switch circuit, so that the receiving circuit determines the abnormal type of the differential port according to the received output signal of the echo cancellation circuit and the output signal of the transmitting circuit, the detection circuit does not need to be additionally provided with an analog circuit, the function of detecting the state of the differential port can be realized only through the switch circuit, the scale of the detection circuit can be reduced, the cost of the detection circuit is saved, the complexity of the detection circuit is reduced, and the detection mode is simplified.

As one embodiment, as shown in fig. 3, two transceiver circuits in the detection circuit include a first transceiver circuit and a second transceiver circuit, the first transceiver circuit includes a first transmitting circuit, a first echo cancellation circuit, a first receiving circuit and a first switch circuit, and the second transceiver circuit includes a second transmitting circuit, a second echo cancellation circuit, a second receiving circuit and a second switch circuit;

Specifically, the structures of the transceiver circuits in the detection circuit may be the same, and the differential ports of the two transceiver circuits are connected by a differential twisted pair. If the detection circuit includes two transceiver circuits, the two transceiver circuits are respectively a first transceiver circuit and a second transceiver circuit, the first transceiver circuit may include a first transmitting circuit, a first echo cancellation circuit, a first receiving circuit and a first switch circuit, and the second transceiver circuit may include a second transmitting circuit, a second echo cancellation circuit, a second receiving circuit and a second switch circuit. The first transmitting circuit and the second transmitting circuit may have the same internal structure and function, the first echo cancellation circuit and the second echo cancellation circuit may have the same internal structure and function, the first receiving circuit and the second receiving circuit may have the same internal structure and function, and the first switching circuit and the second switching circuit may have the same internal structure and function. The output signal of the first transmitting circuit may be two differential signals, and the output signal of the second transmitting circuit may also be two differential signals.

It should be noted that the signal transceiving end of the first transmitting circuit has both a signal transmitting function and a signal receiving function, that is, the first transmitting circuit may transmit the output signal of the first transmitting circuit to the first echo cancellation circuit through the signal transceiving end of the first transmitting circuit, may also transmit the output signal of the first transmitting circuit to the second transmitting circuit through the first differential port and the second differential port through the signal transceiving end of the first transmitting circuit, and may also receive the output signal of the second transmitting circuit through the signal transceiving end of the first transmitting circuit. The signal transceiving end of the second transmitting circuit has both a signal transmitting function and a signal receiving function, that is, the second transmitting circuit may transmit the output signal of the second transmitting circuit to the second echo cancellation circuit through the signal transceiving end of the second transmitting circuit, may transmit the output signal of the second transmitting circuit to the first transmitting circuit through the second differential port and the first differential port through the signal transceiving end of the second transmitting circuit, and may receive the output signal of the first transmitting circuit through the signal transceiving end of the second transmitting circuit.

In addition, the first transceiver circuit in the detection circuit further comprises a first blocking circuit, and the second transceiver circuit further comprises a second blocking circuit; the input end of the first blocking circuit is connected with the output end of the first transmitting circuit, and the input end of the second blocking circuit is connected with the output end of the second transmitting circuit.

It is to be understood that, with continued reference to fig. 2, the first dc blocking circuit in the first transceiver circuit may be two dc blocking capacitors, which are C1 and C2, respectively, and the second dc blocking circuit in the second transceiver circuit may also be two dc blocking capacitors, which are C3 and C4, respectively. The first blocking circuit can prevent the static operating point of the first transmitting circuit from shifting, the second blocking circuit can prevent the static operating point of the second transmitting circuit from shifting, for example, the blocking capacitor C1 prevents the static operating point of the p end of the first transmitting circuit from shifting, the blocking capacitor C2 prevents the static operating point of the n end of the first transmitting circuit from shifting, the blocking capacitor C3 prevents the static operating point of the p end of the second transmitting circuit from shifting, and the blocking capacitor C4 prevents the static operating point of the n end of the second transmitting circuit from shifting.

Further, as shown in fig. 4, two transceiver circuits in the detection circuit include a first transceiver circuit and a second transceiver circuit, the first transceiver circuit includes a first transmitting circuit, a first echo cancellation circuit, a first receiving circuit, a first switch circuit, a first dc blocking capacitor C1 and a second dc blocking capacitor C2, and the second transceiver circuit includes a second transmitting circuit, a second echo cancellation circuit, a second receiving circuit, a second switch circuit, a third dc blocking capacitor C3 and a fourth dc blocking capacitor C4;

Wherein, the signal transceiving end of the first transmitting circuit is simultaneously connected with the first stopping capacitor C1, the second stopping capacitor C2 and the first input end of the first echo cancellation circuit, the first stopping capacitor C1 and the second stopping capacitor C2 are respectively connected with different differential ports in the first differential port, the output end of the first transmitting circuit is connected with the input end of the first switch circuit, the output end of the first switch circuit is connected with the second input end of the first echo cancellation circuit, the output end of the first echo cancellation circuit is connected with the input end of the first receiving circuit,

the signal transceiving end of the second transmitting circuit is simultaneously connected with a third stopping capacitor C3, a fourth stopping capacitor C4 and a first input end of a second echo cancellation circuit, the third stopping capacitor C3 and the fourth stopping capacitor C4 are respectively connected with different differential ports in the second differential port, the output end of the second transmitting circuit is connected with the input end of a second switch circuit, the output end of the second switch circuit is connected with a second input end of the second echo cancellation circuit, the output end of the second echo cancellation circuit is connected with the input end of a second receiving circuit, and the first differential port is correspondingly connected with the second differential port.

Optionally, based on the detection circuit in fig. 4, the first dc blocking capacitor C1 in the detection circuit may prevent the static operating point of the first differential port 1 of the first transmitting circuit from shifting; the second blocking capacitor C2 can prevent the static operating point of the first differential port 2 of the first transmitting circuit from shifting; the third dc blocking capacitor C3 in the detection circuit can prevent the static operating point of the second differential port 3 of the second transmission circuit from shifting; the fourth dc blocking capacitor C4 may prevent the static operating point of the second differential port 4 of the second transmitting circuit from shifting.

The detection circuit can detect the abnormal state of the differential port in each transceiver circuit by the conduction of the switch circuit; the detection circuit does not need to add an additional analog circuit, and can realize the state detection function of the differential port only through the switch circuit, thereby reducing the scale of the detection circuit, saving the cost of the detection circuit, reducing the complexity of the detection circuit and simplifying the detection mode.

As an embodiment, in the detection circuit, the signal transceiving terminal of the first transmitting circuit and the first input terminal of the first echo cancellation circuit form a third path, the output terminal of the first transmitting circuit, the first switch circuit and the second input terminal of the first echo cancellation circuit form a fourth path, the signal transceiving terminal of the second transmitting circuit and the first input terminal of the second echo cancellation circuit form a fifth path, and the output terminal of the second transmitting circuit, the second switch circuit and the second input terminal of the second echo cancellation circuit form a sixth path; the first receiving circuit is used for determining whether the first differential port is abnormal or not according to the output signal of the first echo eliminating circuit when the fourth path is conducted by the first switch circuit; and the second receiving circuit is used for determining whether the second differential port is abnormal or not according to the output signal of the second echo cancellation circuit when the sixth channel is conducted by the second switching circuit.

Specifically, when the first switch circuit turns on the fourth path, the first receiving circuit may determine whether the first differential port is abnormal according to an output signal of the first echo cancellation circuit. Meanwhile, when the fourth path is conducted by the first switch circuit, the first receiving circuit can also determine that the first differential port is in a normal state according to the output signal of the first echo cancellation circuit; meanwhile, when the second switch circuit turns on the sixth path, the second receiving circuit may determine whether the second differential port is abnormal according to an output signal of the second echo cancellation circuit. Meanwhile, when the second switch circuit is turned on to the sixth path, the second receiving circuit may further determine that the second differential port is in a normal state according to an output signal of the second echo cancellation circuit. The abnormal state of the first differential port and the abnormal state of the second differential port may be the same or different. The abnormal state of the first differential port and the abnormal state of the second differential port can be both states of a first differential port short two-way, a first differential port open one-way short one-way, a first differential port short one-way normal one-way, a first differential port open one-way normal one-way and the like. Or both the first differential port and the second differential port can be in a normal state. The first transceiver circuit may include two first switch circuits, and the second transceiver circuit may include two second switch circuits. The output signals of the first echo cancellation circuit and the second echo cancellation circuit can be two differential signals.

It should be noted that the first differential port in the first transceiver circuit is connected to the second differential port in the second transceiver circuit through a differential twisted pair. The first transceiver circuit may include two first switch circuits, wherein the first transmitter circuit and the second transmitter circuit may receive signals transmitted by other circuits and process the respective received signals to obtain two differential signals, the two differential signals output by the first transmitter circuit may be denoted as TXp1 and TXn1, the two differential signals output by the first transmitter circuit may be denoted as TXp1 and TXn1, the two differential signals have the same amplitude and are 180 degrees apart from each other, the two differential signals output by the corresponding first echo cancellation circuit may be denoted as RXp1 and RXn1, the RXp1 and RXn1 are differentially complementary, the RXp1 and RXn1 are differentially complementary, and the two differential signals have the same amplitude and are 180 degrees apart from each other. The second transceiver circuit may include two second switch circuits, the two differential signals output by the second transmitting circuit may be denoted as TXp2 and TXn2, TXp2 may be equal to-TXn 2, the two differential signals output by the corresponding second echo cancellation circuit may be denoted as RXp2 and RXn2, and RXp2 may be equal to-RXn 2. Wherein the output signal of the first switching circuit may be equal to TXP1-TXn1, and RX may be equal to the output signal of the first transceiving circuit minus the output signals (TXP 1-TXn 1) of the first switching circuit; when the first echo cancellation circuit is not operating, the output signal of the first transceiver circuit may be equal to 0, and at this time, RX may be equal to the output signal of the first transceiver circuit. In the detection circuit, a first transceiver circuit and a second transceiver circuit both comprise two differential ports, the first transceiver circuit comprises a first differential port 1 and a first differential port 2, the second transceiver circuit comprises a second differential port 3 and a second differential port 4, the first differential port 1 and the second differential port 3 are connected through a differential twisted pair, and the first differential port 2 and the second differential port 4 are connected through a differential twisted pair. In this embodiment, the state detection may be performed on the first differential port 1 and the first differential port 2 in the first transceiver circuit, and the state detection may be performed on the second differential port 3 and the second differential port 4 in the second transceiver circuit, and meanwhile, the first differential port 1, the first differential port 2, the second differential port 3, and the second differential port 4 may be periodically performed according to a preset interval time.

Illustratively, the output signal of the first transmitting circuit in the first transceiver circuit is TX1 (including TXp1+ TXn 1), the output signal of the first echo cancellation circuit is RX1 (including RXp1+ RXn 1), the output signal of the second transmitting circuit in the second transceiver circuit is TX2 (including TXp2+ TXn 2), the output signal of the second echo cancellation circuit is RX2 (including RXp2+ RXn 2), and the first receiving circuit determines a status detection result of the first differential port according to the output signal RX1 of the first echo cancellation circuit, where the status detection result is shown in table 1, where a represents a link attenuation coefficient, and a may be greater than 1. Fig. 5 is a structural diagram illustrating 6 state detection results corresponding to the first

differential ports

1 and 2 in the first transceiver circuit.

TABLE 1

In this embodiment, when the first transceiver circuit is short-circuited, TXp1= TXn1 in the output signals of the first transceiver circuit, the output signals of the first transceiver circuit when the first transceiver circuit is open are 2TXp1 and 2TXn1, respectively, and the output signals of the first transceiver circuit when the first transceiver circuit is normal are TXp1 and TXn 1. When the first echo cancellation circuit works, the output signal RX of the first echo cancellation circuit is equal to the output signal of the first transceiver circuit minus the output signal (TXp 1-TXn 1) of the first switch circuit, and may also be equal to (TXp 1-TXn 1) + (TXp 2-TXn 2)/a- (TXp 1-TXn 1) = (TXp 2-TXn 2)/a = TX2/a, where TX2/a represents that the output signal of the second transceiver circuit reaches the value of RX received by the first transceiver circuit after being attenuated by a times by the link, and in this case, it may be determined that the first differential port is normal; when the first echo cancellation circuit works, the output signal RX of the first echo cancellation circuit is equal to the output signal of the first transceiver circuit minus the output signal (TXP 1-TXn 1) of the first switch circuit, and can also be equal to-TX 1, -TX1 represents that the output signal of the first transceiver circuit reaches the value of the receiving RX of the first transceiver circuit after being inverted, and in this case, the first differential port can be determined to be short-circuited; when the first echo cancellation circuit does not work, the output signal RX of the first echo cancellation circuit is equal to the output signal of the first transceiver circuit, and may also be equal to a direct current level, in which case it may be determined that the first differential port is short-circuited; when the first echo cancellation circuit does not work, the output signal RX of the first echo cancellation circuit is equal to the output signal TX of the first transceiver circuit minus the output signal (TXp 1-TXn 1) of the first switch circuit, and may also be equal to 2TXp1-TXn1-TXn2/a- (TXp 1-TXn 1) = TXp1-TXn2/a, and when the TXp1-TXn2/a represents one path in the first differential port (here, set as the p-side), the output signal RX of the first transceiver circuit minus the normal end (here, set as the n-side) of the second differential port passes through the link attenuation a times to reach the value of the receiving RX of the first transceiver circuit, in which case it may be determined that one path is opened in the first differential port, and the p-side is opened; when the first echo cancellation circuit is operated, the output signal RX of the first echo cancellation circuit is equal to the output signal TX of the first transceiving circuit minus the output signal (TXp 1-TXn 1) of the first switch circuit, and may also be equal to 2TXp1-2TXn1- (TXp 1-TXn 1) = TXp1-TXn1= TX1, TX1 indicates that the output signal of the first transceiving circuit reaches the value of RX received by the first transceiving circuit, in this case, two open paths in the first differential port may be determined, and when the first echo cancellation circuit does not operate, the output signal RX of the first echo cancellation circuit may be equal to the output signal TX of the first transceiver circuit, and may also be equal to 2TXp1-2TXn1=2TX1, where 2 × TX1 indicates that the amplitude of the output signal of the first transceiver circuit multiplied by 2 reaches the value of the first transceiver circuit receiving RX.

Continuing to make the detection circuit, TX1= TXp1-TXn1, TX2= TXp2-TXn2, TXp1= -TXn1, and TXp2= -TXn2, wherein the normal standard signal TXp2 takes three levels of (-1, 0, 1), and the distance between the three levels is 1. In order to better distinguish the level value of the first transceiver circuit, the level value of the first transceiver circuit is higher than the standard signal level value in the second transceiver circuit by 0.5 level interval, i.e. 1.5 is the optimal resolution value. Therefore, in order to eliminate the interference of the standard signal in the second transceiver circuit on the output signal of the first transmitter circuit in the first transceiver circuit, the two-level value of TXp1 in the output signal of the first transmitter circuit is (-1.5, 1.5), and the normal attenuation of the link is a times (a may be greater than or equal to 1), so that the detection result of the state of the second differential port determined by the first receiver circuit according to the output signal RX1 of the first echo cancellation circuit is shown in table 2 on the basis of table 1. The link may be a first dc blocking capacitor C1, a second dc blocking capacitor C2, a third dc blocking capacitor C3, a fourth dc blocking capacitor C4 and a differential twisted pair in the detection circuit of fig. 4.

TABLE 2

In addition, the output signal TXp1 of the first transmitting circuit is equal to-TXn 1= (-1.5, 1.5), the period is T, a square wave test signal with a duty ratio of 1:1 is input to the detecting circuit, and on the basis of the operation of the first echo cancellation circuit (i.e. the conduction of the first switch circuit): (1) if the receiving signal RX of the first receiving circuit is 1 level (0), it may be determined that "one open circuit and one short circuit" are in the first differential port 1 and the first differential port 2; (2) if the reception signal RX of the first reception circuit includes 3 levels including 0 level, it may be determined that "two paths are normal" in the first differential port 1 and the first differential port 2; (3) if the receiving signal RX of the first receiving circuit includes 6 levels including the standard signal (-1.5, 1.5), the first echo cancellation circuit can be switched to the inactive state; (4) if the reception signal RX of the first reception circuit includes only (-3, 3), the first echo cancellation circuit may be switched to the inactive state. Meanwhile, on the basis that the first echo cancellation circuit is not operated (i.e., the first switch circuit is not turned on): (1) if the receiving signal RX of the first receiving circuit is 1 level (0), it may be determined that the first differential port 1 and the first differential port 2 are "short two paths"; (2) if the reception signal RX of the first reception circuit includes only (-6, 6), it may be determined that the first differential port 1 and the first differential port 2 are "open two ways"; (3) if the receiving signal RX of the first receiving circuit includes 6 levels including the standard signal (-1.5, 1.5), it can be determined that the "short normal path" is included in the first differential port 1 and the first differential port 2; (3) if the reception signal RX of the first reception circuit includes 6 levels of the standard signal (-4.5, 4.5), it can be determined that "the first differential port 1 is open and the first differential port 2 is normal.

If the output signal RX1 of the first echo cancellation circuit is (-3, 3), (-1.5, 1.5), (-6, 6) and (0), these signals are not a function of a and are obviously different from the standard signal in the second transceiver circuit, so as to ensure that the state detection result is not affected by the value of the link attenuation a, and each transceiver circuit is not affected by whether the other transceiver circuit transmits a signal or not.

In this embodiment, in order to avoid loss of generality, port 1 and port 2 in the first differential port may be detected, and port 3 and port 4 in the second differential port may be detected. Compared with the prior art, the first switch circuit is added in the first echo elimination circuit, the output signal RX of the first echo elimination circuit, namely the level value of the receiving signal (RXP 1-RXn 1), is changed by whether echo elimination is carried out or not (wherein the first echo elimination circuit works when the first switch circuit is conducted, and the first echo elimination circuit does not work when the first switch circuit is not conducted), and meanwhile, the amplitude (-1.5, 1.5) of the output signal (TXP 1 and TXn 1) of the first transmitting circuit is different from the amplitude (-1, 0, 1) of the normally used standard signal (TXP 2 and TXn 2), so that one side of the detection circuit can be ensured not to be influenced by the signals (TXP 2 and TXn 2) of the other side circuit.

Fig. 6 is a schematic flow chart of the detection method provided in this embodiment, and as shown in fig. 6, the method may be implemented by the following steps:

s100, acquiring a first output signal of the transmitting circuit.

Specifically, the echo cancellation circuit in the detection circuit may receive the first output signal output by the transmission circuit. The first output signal of the transmitting circuit may be two differential signals, and the phase difference between the two differential signals is 180 degrees.

And S200, controlling the conduction state of the switch circuit.

It should be noted that the detection circuit may receive a control command, and then control the conducting state of the switch circuit in the detection circuit in response to the control command, where the conducting state may be conducting or non-conducting. That is, the switching circuit is controlled to be closed or opened. The control instruction can be an instruction generated by an input control signal, and the input mode can be a mode that a user presses a control function button, or a mode that the user inputs voice information, and the like; the control function button can be a closing button or an opening button of the switch circuit, and the voice message can be related information of closing or opening of the switch circuit.

And S300, if the switch circuit is conducted, determining whether the differential port is abnormal or not according to the first output signal and a second output signal of the echo cancellation circuit.

Specifically, if the control switch circuit is turned on, the receiving circuit in the detection circuit may perform operation, comparison, analysis, and/or conversion on the first output signal of the transmitting circuit and the second output signal of the echo cancellation circuit, so as to determine whether the differential port is abnormal. The abnormal state of the differential port can be states of a short two-way differential port, an open two-way differential port, a short one-way open one-way differential port, a normal one-way short one-way differential port, a normal one-way open one-way differential port and the like. The second output signal of the echo cancellation circuit may also be two differential signals.

The detection method can acquire a first output signal of the transmitting circuit, control the conduction state of the switch circuit, and determine whether the differential port is abnormal or not according to the first output signal and a second output signal of the echo cancellation circuit if the switch circuit is conducted; the method can control the echo cancellation circuit to process the received signal by controlling the conduction state of the switch circuit so as to obtain a second output signal of the echo cancellation circuit, and further determine whether the differential port is abnormal according to the first output signal of the transmitting circuit and the second output signal of the echo cancellation circuit.

As an embodiment, as shown in fig. 7, when the switch circuit is turned on in S300, the step of determining whether the differential port is abnormal according to the first output signal and the second output signal of the echo cancellation circuit may include:

and S310, if the conducting state of the switch circuit is a high level state, judging whether a second output signal of the echo cancellation circuit is the same as a first preset signal or not.

Specifically, if the on state of the switch circuit is a high level state, the receiving circuit in the detection circuit may determine whether the second output signal of the echo cancellation circuit is the same as the first preset signal. The on state of the switch circuit being a high state may be understood as a switch circuit closed state. The second output signal may be a single-level signal, a two-level signal, a three-level signal, a four-level signal, and so on. The first output signal of the transmitting circuit is different from the second output signal of the echo cancellation circuit, which may be understood as that the number of levels included in the first output signal is different from the number of levels included in the second output signal, and/or that the values of the corresponding levels in the first output signal and the second output signal are different.

And S320, if the second output signal of the echo cancellation circuit is the same as the first preset signal, opening one path in the differential port to be a short path.

It should be noted that, if the receiving circuit in the detection circuit determines that the second output signal of the echo cancellation circuit is the same as the first preset signal, it is determined that one of the differential ports is a short. The first preset signal may be a single-level signal, that is, a high-level signal 1 or a low-level signal 0, and in this embodiment, the first preset signal is a low-level signal 0. The first output signal of the transmitting circuit is the same as the second output signal of the echo cancellation circuit, which means that the number of levels included in the first output signal is the same as the number of levels included in the second output signal, and the values of the corresponding levels in the first output signal and the second output signal are also the same.

S330, if the second output signal of the echo cancellation circuit is different from the first preset signal, judging whether the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal.

It can be understood that, if the receiving circuit in the detection circuit determines that the second output signal of the echo cancellation circuit is different from the first preset signal, it may be further determined whether the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal. The second output signal of the echo cancellation circuit may be equal to or different from the second preset signal or the third preset signal.

S340, if a second output signal of the echo cancellation circuit is the same as a second preset signal or a third preset signal, determining that the differential port is abnormal, wherein the second preset signal is a signal determined according to the first numerical value and the first output signal of the transmitting circuit; the third preset signal is equal to a first preset number of signals comprising the first output signal of the transmitting circuit.

Specifically, if the receiving circuit in the detection circuit determines that the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal, it may be determined that the differential port is abnormal. Alternatively, if the output signal of the transmitting circuit is (-1.5, 1.5), the second predetermined signal may be equal to a signal determined according to the first value and the output signal of the transmitting circuit; the first value may be any constant other than 0, but in the present embodiment, the first value may be equal to 2, that is, the second preset signal may be equal to (-3, 3). Optionally, the first preset number may be any constant other than 0, but is not equal to the first value, and in this embodiment, the first preset number may be equal to 6, so that the third preset signal may be equal to 6 signals including the output signal (-1.5, 1.5) of the transmitting circuit, and it is also understood that the remaining 4 signals other than-1.5 and 1.5 in the third preset signal may be level signals.

According to the detection method, when the switch circuit is switched on, the abnormity of the differential port can be determined according to the first output signal of the transmitting signal and the second output signal of the echo cancellation circuit; the method can control the echo cancellation circuit to process the received signal by controlling the conduction state of the switch circuit so as to obtain a second output signal of the echo cancellation circuit, then the receiving circuit determines that the differential port is abnormal according to the first output signal of the transmitting circuit and the second output signal of the echo cancellation circuit, an additional analog circuit is not needed in the process to realize the detection method, the scale of the detection circuit can be reduced on the basis of ensuring the detection function of the differential port state, the cost of the detection circuit is saved, the complexity of the detection circuit is reduced, and the detection mode is simplified.

As an embodiment, as shown in fig. 8, if the second output signal of the echo cancellation circuit in S340 is the same as the second preset signal or the third preset signal, the step of determining that the differential port is abnormal may be implemented by:

s341, if the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal, controlling the on state of the switch circuit to be a low level state.

Specifically, if the receiving circuit in the detection circuit determines that the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal, the on state of the switch circuit may be controlled to be the low level state, that is, the switch circuit is switched from the high level state to the low level state. The on state of the switch circuit being a low state may be understood as a state that closes the switch circuit.

And S342, determining the abnormal type of the differential port according to the level number included in the first output signal and the level number included in the second output signal.

It is to be understood that the receiving circuit in the detection circuit may determine the abnormality type of the differential port by performing comparison processing, arithmetic processing, conversion processing, and/or analysis processing, and the like, on the number of levels included in the first output signal and the number of levels included in the second output signal.

As shown in fig. 9, the step of determining the abnormal type of the differential port according to the number of levels included in the first output signal and the number of levels included in the second output signal in S342 may include:

s3421, if the number of levels included in the second output signal is smaller than the number of levels included in the first output signal, determining that the abnormal type of the differential port is that the differential port is short.

S3422, if the number of levels included in the second output signal is equal to the number of levels included in the first output signal and the output signal of the echo cancellation circuit is equal to the fourth preset signal, determining that the abnormal type of the differential port is that the differential port has two paths.

S3423, if the number of levels included in the second output signal is greater than the number of levels included in the first output signal and the second output signal is equal to the third preset signal, determining that the abnormal type of the differential port is the short normal path in the differential port.

S3424, if the number of levels included in the second output signal is greater than the number of levels included in the first output signal and the second output signal is equal to the fifth preset signal, determining that the abnormal type of the differential port is a normal one of the differential ports.

Specifically, the receiving circuit may determine whether the number of levels included in the output signal of the echo cancellation circuit is smaller than the number of levels included in the output signal of the transmitting circuit, and may determine that the abnormal type of the differential port is two paths short of the differential port if it is determined that the number of levels included in the output signal of the echo cancellation circuit is smaller than the number of levels included in the output signal of the transmitting circuit.

Or, the receiving circuit may determine whether the number of levels included in the output signal of the echo cancellation circuit is equal to the number of levels included in the output signal of the transmitting circuit, and determine whether the output signal of the echo cancellation circuit is equal to a fourth preset signal, and if it is determined that the number of levels included in the output signal of the echo cancellation circuit is equal to the number of levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to the fourth preset signal, it may be determined that the abnormal type of the differential port is that the differential port is opened in two ways. Optionally, the fourth preset signal is equal to a signal determined according to the second value and an output signal of the transmitting circuit; the second value may be any constant other than 0, but in this embodiment the first value may be equal to 4, i.e. the second predetermined signal may be equal to (-6, 6).

Or, the receiving circuit may determine whether the number of levels included in the output signal of the echo cancellation circuit is greater than the number of levels included in the output signal of the transmitting circuit, and determine whether the output signal of the echo cancellation circuit is equal to a third preset signal, and if it is determined that the number of levels is greater than the number of levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to the third preset signal, it may be determined that the abnormal type of the differential port is the normal one of the short path in the differential port. Alternatively, the third preset signal may be equal to a first preset number of signals comprising the output signal of the transmitting circuit. The first predetermined number may be any constant other than 0, but is not equal to the first value, and in this embodiment, the first predetermined number may be equal to 6, so that the third predetermined signal may be equal to 6 signals including the output signal (-1.5, 1.5) of the transmitting circuit, and it is also understood that the remaining 4 signals other than-1.5 and 1.5 in the third predetermined signal may be level signals.

Or, the receiving circuit may determine whether the number of levels included in the output signal of the echo cancellation circuit is greater than the number of levels included in the output signal of the transmitting circuit, and determine whether the output signal of the echo cancellation circuit is equal to a fifth preset signal, and if it is determined that the number of levels included in the output signal of the echo cancellation circuit is greater than the number of levels included in the output signal of the transmitting circuit and whether the output signal of the echo cancellation circuit is equal to the fifth preset signal, may determine that the abnormal type of the differential port is one of the normal paths in the differential port.

When the detection method determines that the differential port is abnormal, the switch circuit can be continuously controlled to be opened, and the abnormal type of the differential port is further determined according to the level number included in the first output signal of the transmitting signal and the second output signal of the echo cancellation circuit; the method can determine the abnormal type of the differential port by controlling the conduction state of the switch circuit, the detection method is realized without an additional analog circuit in the process, the scale of the detection circuit can be reduced on the basis of ensuring the detection function of the differential port state, the cost of the detection circuit is saved, the complexity of the detection circuit is reduced, and the detection mode is simplified.

In order to facilitate understanding of those skilled in the art, the detection method provided in the present application is described by taking an implementation subject as a detection circuit as an example, and specifically, the method includes:

(1) a first output signal of a transmit circuit is obtained.

(2) The conducting state of the switch circuit is controlled.

(3) And if the conducting state of the switch circuit is a high level state, judging whether the second output signal of the echo cancellation circuit is the same as the first preset signal.

(4) And if the second output signal of the echo cancellation circuit is the same as the first preset signal, determining that one of the differential ports is short.

(5) And if the second output signal of the echo cancellation circuit is different from the first preset signal, judging whether the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal.

(6) If the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal, determining that the differential port is abnormal; the second preset signal is a signal determined according to the first value and the first output signal of the transmitting circuit; the third predetermined signal is equal to a first predetermined number of signals comprising the first output signal of the transmitting circuit.

(7) And if the second output signal of the echo cancellation circuit is the same as the second preset signal or the third preset signal, controlling the conduction state of the switch circuit to be in a low level state.

(8) And if the number of the levels included in the second output signal is smaller than that of the levels included in the first output signal, determining that the abnormal type of the differential port is that the differential port is short in two paths.

(9) And if the number of the levels included in the second output signal is equal to the number of the levels included in the first output signal and the output signal of the echo cancellation circuit is equal to the fourth preset signal, determining that the abnormal type of the differential port is that the differential port is opened in two ways.

(10) And if the number of levels included in the second output signal is greater than that included in the first output signal and the second output signal is equal to a third preset signal, determining that the abnormal type of the differential port is a short normal path in the differential port.

(11) If the number of levels included in the second output signal is larger than that included in the first output signal and the second output signal is equal to a fifth preset signal, determining that the abnormal type of the differential port is a normal one of the differential ports;

For the implementation processes of (1) to (11), reference may be specifically made to the description of the above embodiments, and the implementation principle and the technical effect are similar, which are not described herein again.

It should be understood that although the various steps in the flow charts of fig. 6-9 are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Also, at least some of the steps in fig. 6-9 may include multiple steps or multiple stages, which are not necessarily performed at the same time, but may be performed at different times, which are not necessarily performed in sequence, but may be performed in turn or alternately with other steps or at least some of the other steps.

In one embodiment, a chip is provided, which includes the detection circuit in any of the embodiments corresponding to fig. 1-4 described above, and the detection circuit is configured to perform the method in any of the embodiments corresponding to fig. 1-4 described above.

It should be noted that, for simplicity of description, the foregoing method embodiments are described as a series of circuit combinations, but those skilled in the art should understand that the present application is not limited by the described circuit combinations, because some circuits may be implemented in other ways or structures according to the present application. Further, those skilled in the art should also appreciate that the embodiments described in the specification are all alternative embodiments, and that the devices and modules referred to are not necessarily required for this application.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to the related descriptions of other embodiments.

The above examples only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present application. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A detection circuit, characterized in that the detection circuit comprises: the differential ports between the two transceiver circuits are mutually connected; the receiving and transmitting circuit comprises a transmitting circuit, a blocking capacitor, an echo eliminating circuit, a switching circuit and a receiving circuit; a first path is formed by a first output end of the transmitting circuit and a first input end of the echo cancellation circuit, and a second path is formed by a second output end of the transmitting circuit, an output end of the switch circuit and a second input end of the echo cancellation circuit; one end of the blocking capacitor is respectively connected with the first output end of the transmitting circuit and the first input end of the echo cancellation circuit; the blocking capacitor is used for preventing the static working point of the differential port of the transmitting circuit from shifting to generate signal distortion; the two transceiver circuits comprise a first transceiver circuit and a second transceiver circuit; the level value of the first transceiver circuit is higher than the level value of the standard signal in the second transceiver circuit by 0.5 level interval;

the receiving circuit is configured to, when the switch circuit turns on the second path, determine that one of the differential ports is short if it is detected that an output signal of the echo cancellation circuit is equal to a first preset signal, or turn off the second path through the switch circuit if it is detected that the output signal of the echo cancellation circuit is equal to a second preset signal or equal to a third preset signal, and determine an abnormal type of the differential port according to a level number included in the output signal of the echo cancellation circuit; the second preset signal is a signal determined according to the first value and the output signal of the transmitting circuit; the third preset signal is equal to a first preset number of signals including the output signal of the transmitting circuit; the abnormal type of the differential port comprises two short paths of the differential port, two open paths of the differential port, a normal one path of the short path in the differential port or a normal one path of the open path in the differential port; the output signal of the transmitting circuit is.

2. The detection circuit of claim 1, wherein the receiving circuit is configured to determine whether the differential port is abnormal according to an output signal of the echo cancellation circuit and an output signal of the transmitting circuit when the switch circuit turns on the second path.

3. The detection circuit of claim 2, wherein the second path is opened by the switching circuit if the differential port is determined to be abnormal.

4. The detection circuit according to claim 3, wherein the receiving circuit is specifically configured to, when the switch circuit disconnects the second path, determine that the abnormal type of the differential port is that the differential port is short in two paths if it is detected that the number of levels is smaller than the number of levels included in the output signal of the transmitting circuit; or if the number of the detected levels is equal to the number of the levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to a fourth preset signal, determining that the abnormal type of the differential port is that the differential port is opened by two paths; or if it is detected that the number of levels is greater than the number of levels included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is equal to the third preset signal, determining that the abnormal type of the differential port is a normal short path in the differential port; or if the level number is detected to be larger than the level number included in the output signal of the transmitting circuit and the output signal of the echo cancellation circuit is detected to be equal to a fifth preset signal, determining that the abnormal type of the differential port is one normal path of the differential port.

5. The detection circuit according to claim 4, characterized in that said fourth preset signal is equal to a signal determined according to a second value and an output signal of said transmission circuit; the fifth preset signal is a second preset number of signals including a sixth preset signal, and the sixth preset signal is equal to a signal determined according to a third value and an output signal of the transmitting circuit.

6. The detection circuit of claim 1, wherein the receiving circuit is further configured to determine that the differential port is normal if the output signal of the echo cancellation circuit is detected to be equal to a third predetermined number of signals including the first predetermined signal when the switching circuit turns on the second path.

7. The detection circuit according to any one of claims 1-6, wherein the first transceiver circuit comprises a first transmit circuit, a first echo cancellation circuit, a first receive circuit, and a first switch circuit, wherein the second transceiver circuit comprises a second transmit circuit, a second echo cancellation circuit, a second receive circuit, and a second switch circuit, and wherein the differential port comprises a first differential port and a second differential port;

Wherein, the signal transceiving end of the first transmitting circuit is connected with the first differential port and the first input end of the first echo cancellation circuit, the output end of the first transmitting circuit is connected with the input end of the first switch circuit, the output end of the first switch circuit is connected with the second input end of the first echo cancellation circuit, the output end of the first echo cancellation circuit is connected with the input end of the first receiving circuit, the signal transceiving end of the second transmitting circuit is connected with the second differential port and the first input end of the second echo cancellation circuit, the output end of the second transmitting circuit is connected with the input end of the second switch circuit, the output end of the second switch circuit is connected with the second input end of the second echo cancellation circuit, the output end of the second echo cancellation circuit is connected with the input end of the second receiving circuit, and the first differential port is connected with the second differential port.

8. The detection circuit of claim 7, wherein the signal transceiving terminal of the first transmitting circuit forms a third path with the first input terminal of the first echo cancellation circuit, the output terminal of the first transmitting circuit and the first switch circuit form a fourth path with the second input terminal of the first echo cancellation circuit, the signal transceiving terminal of the second transmitting circuit forms a fifth path with the first input terminal of the second echo cancellation circuit, and the output terminal of the second transmitting circuit and the second switch circuit form a sixth path with the second input terminal of the second echo cancellation circuit;

The first receiving circuit is configured to determine whether the first differential port is abnormal according to an output signal of the first echo cancellation circuit when the fourth path is turned on by the first switching circuit;

the second receiving circuit is configured to determine whether the second differential port is abnormal according to an output signal of the second echo cancellation circuit when the sixth path is turned on by the second switch circuit.

9. A method of detection, the method comprising:

acquiring a first output signal of a transmitting circuit;

controlling the conduction state of the switch circuit;

if the switch circuit is switched on and a second output signal of the echo cancellation circuit is detected to be equal to a first preset signal, determining that one of the differential ports is short;

if the switch circuit is switched on and a second output signal of the echo cancellation circuit is detected to be equal to a second preset signal or a third preset signal, the switch circuit is switched off, then a current output signal of the echo cancellation circuit is obtained, and the abnormal type of the differential port is determined according to the level number included in the current output signal of the echo cancellation circuit;

the second preset signal is a signal determined according to a first value and a first output signal of the transmitting circuit; the third preset signal is equal to a first preset number of signals including the first output signal of the transmitting circuit; the abnormal type of the differential port comprises the states of two short paths of the differential port, two open paths of the differential port, a normal one path of the short path in the differential port or a normal one path of the open path in the differential port;

The transmitting circuit and the echo cancellation circuit are respectively connected with one end of a blocking capacitor, and the blocking capacitor is used for preventing a static working point of a differential port of the transmitting circuit from shifting to generate signal distortion;

the steps in the detection method are performed by a detection circuit as described in claim 1 above; the detection circuit comprises a first transceiving circuit and a second transceiving circuit; the level value of the first transceiver circuit is higher than the level value of the standard signal in the second transceiver circuit by 0.5 level interval.

10. A chip, characterized in that it comprises a detection circuit according to any one of claims 1 to 8;

the detection circuit for performing the steps of the method as claimed in claim 9.