CN109962865B

CN109962865B - Display module and display system for realizing network loop transmission

Info

Publication number: CN109962865B
Application number: CN201711408278.2A
Authority: CN
Inventors: 李卫刚; 王�华; 秦海华
Original assignee: Shenzhen Huasheng Software Technology Co ltd; TCL Commercial Information Technology Huizhou Co Ltd
Current assignee: Shenzhen Huasheng Software Technology Co.,Ltd.; TCL Commercial Information Technology Huizhou Co Ltd
Priority date: 2017-12-22
Filing date: 2017-12-22
Publication date: 2021-07-06
Anticipated expiration: 2037-12-22
Also published as: CN109962865A

Abstract

The invention discloses a display module and a display system for realizing network loop transmission, wherein the display system comprises a control host, a network switch and a plurality of display modules; the plurality of display modules are connected in series through a network cable; the control host outputs a corresponding network signal according to the network video to be displayed, and the network switch outputs the network signal to a display module connected with the network switch; the display module converts the network signal into a network protocol signal and transmits the network protocol signal to the display screen for display, and the display module also outputs the network signal to a subordinate display module connected with the display module. The network signal can be displayed on the current display module, and can also be transmitted to other display screens in a loop-through mode for display, a plurality of converters are not needed, the occupied space is small, and the cost is saved; meanwhile, the plurality of display modules are connected in series through the network cable, so that the wiring is very simple and the operation is convenient; thereby the problem that the cost is higher and the wiring is troublesome is shown to current many screens has been solved.

Description

Display module and display system for realizing network loop transmission

Technical Field

The invention relates to the technical field of display, in particular to a display module and a display system for realizing network loop transmission.

Background

In a conventional monitor or display unit, interfaces such as cvbs (composite Video Broadcast signal), vga (Video Graphics array), HDMI (High Definition Multimedia Interface), dvi (digital Visual Interface), dp (display port) are mostly used as input of signals. When multi-screen display is required, each display unit (display unit No. 1 to display unit No. N) needs to be respectively configured with a converter, as shown in FIG. 1, a control host generates a plurality of IP streams through a network switch and transmits the IP streams to the corresponding converters; each converter converts the received IP stream into a network protocol signal recognizable by the display screen, and outputs the network protocol signal to the corresponding display unit through a corresponding interface (fig. 1 takes an HDMI interface as an example) for display.

However, with the development of the internet and the application of a large amount of streaming media, the input and transmission of network signals are increasingly applied to display systems in various industries. The network signal is input into the display system as a display signal, and particularly in some special application scenarios, such as rail transit, the required content is displayed through network transmission. If the existing multi-screen display mode is still adopted, a plurality of converters are needed, the occupied space is large, and the cost is high; meanwhile, the parallel control mode of a plurality of display units requires a network switch to lead out a plurality of transmission lines, and the wiring is troublesome.

Accordingly, the prior art is yet to be improved and developed.

Disclosure of Invention

In view of the foregoing disadvantages of the prior art, an object of the present invention is to provide a display module and a display system for implementing network loop transmission, which aim to solve the problems of high cost and troublesome wiring of the existing multi-screen display.

The technical scheme adopted by the invention for solving the technical problem is as follows:

a display module for realizing network loop transmission is connected with a display screen and comprises a loop unit, a network switching unit, a processing unit and an LVDS interface;

the loop-through unit receives the network signal, outputs the network signal to a lower-level display module connected with the loop-through unit when an internal passage of the loop-through unit is cut off, and outputs the network signal to the network switching unit when the internal passage is switched on; the network switching unit encodes the network signal and converts the network signal into a network protocol signal, and the network switching unit transmits the network protocol signal to the processing unit for signal processing and then outputs the signal to the display screen for display through the LVDS interface; the network switching unit also outputs the input network signal to the lower display module through the loop-through unit.

In the display module for realizing network loop transmission, the loop unit comprises a first DB-9 interface, a second DB-9 interface and a signal relay circuit;

when the display module is a first display module, the first DB-9 interface is connected with the network switch, and the second DB-9 interface is connected with the lower display module; the first DB-9 interfaces of other display modules are connected with the upper display module, and the second DB-9 interfaces are connected with the lower display module;

the first DB-9 interface receives network signals and transmits the network signals to the signal relay circuit; when the signal relay circuit is powered off, the internal path is cut off, and the output network signal is output to a first DB-9 interface of a lower-level display module connected with the output network signal through a second DB-9 interface; and the signal relay circuit is conducted when being electrified, namely the internal path is conducted, the network signal is output to the network switching unit, and the network signal output by the network switching unit is also transmitted to the first DB-9 interface of the lower-level display module.

In the display module for realizing network loop transmission, the network switching unit comprises a network transformer circuit and a PHY chip;

the network transformer circuit performs enhancement processing on the input network signal; the PHY chip encodes the processed signals and converts the encoded signals into network protocol signals which can be identified by the display screen, and transmits the processed signals back to the network transformer circuit to be fed back to the signal relay circuit.

In the display module for realizing network loop-through transmission, the loop-through unit further comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor and an eighth resistor;

the 1 st pin of the first DB-9 interface is connected with the signal relay circuit through a first resistor, the 6 th pin of the first DB-9 interface is connected with the signal relay circuit through a second resistor, the 2 nd pin of the first DB-9 interface is connected with the signal relay circuit through a third resistor, the 3 rd pin of the first DB-9 interface is connected with the signal relay circuit through a fourth resistor, the 1 st pin of the second DB-9 interface is connected with the signal relay circuit through a fifth resistor, the 6 th pin of the second DB-9 interface is connected with the signal relay circuit through a sixth resistor, the 2 nd pin of the second DB-9 interface is connected with the signal relay circuit through a seventh resistor, and the 3 rd pin of the second DB-9 interface is connected with the signal relay circuit through an eighth resistor.

In the display module for realizing network loop transmission, the signal relay circuit comprises a first relay, a second relay, a third relay, a fourth relay, a first capacitor, a second capacitor, a third capacitor and a fourth capacitor;

the 1 st pin of the first relay is connected with a power supply end IN _5V and is grounded through a first capacitor; a pin 2 of the first relay is connected with a pin 1 of the second DB-9 interface through a fifth resistor, a pin 3 of the first relay is connected with a pin 1 of the first DB-9 interface through a first resistor, a pin 4 and a pin 5 of the first relay are both connected with a network transformer circuit, a pin 6 of the first relay is connected with a pin 2 of the first DB-9 interface through a third resistor, and a pin 7 of the first relay is connected with a pin 2 of the second DB-9 interface through a seventh resistor;

the 1 st pin of the second relay is connected with the power supply end and is grounded through a second capacitor; a pin 2 of the second relay is connected with a pin 3 of the second DB-9 interface through an eighth resistor, the pin 3 of the second relay is connected with a pin 3 of the first DB-9 interface through a fourth resistor,

pins

4 and 5 of the second relay are both connected with a network transformer circuit, a pin 6 of the second relay is connected with a pin 6 of the first DB-9 interface through a second resistor, and a pin 7 of the second relay is connected with a pin 6 of the second DB-9 interface through a sixth resistor;

the 1 st pin of the third relay is connected with the power supply end and is grounded through a third capacitor; a pin 3 of the third relay is connected with a pin 1 of the second DB-9 interface through a fifth resistor, a pin 4 and a pin 5 of the third relay are both connected with the network transformer circuit, and a pin 6 of the third relay is connected with a pin 2 of the second DB-9 interface through a seventh resistor;

the 1 st pin of the fourth relay is connected with the power supply end and is grounded through a fourth capacitor; and the 3 rd pin of the fourth relay is connected with the 3 rd pin of the second DB-9 interface through an eighth resistor, the 4 th pin and the 5 th pin of the fourth relay are both connected with the network transformer circuit, and the 6 th pin of the fourth relay is connected with the 6 th pin of the second DB-9 interface through a sixth resistor.

In the display module for realizing network loop-through transmission, the network transformer circuit comprises a first transformer, a second transformer, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor and a tenth capacitor;

the No. 1 pin of the first transformer is connected with the No. 4 pin of the PHY chip, and the No. 2 pin of the first transformer is connected with a power supply end and is grounded through a fifth capacitor; a pin 3 of the first transformer is connected with a pin 3 of the PHY chip, a pin 6 of the first transformer is connected with a pin 128 of the PHY chip, and a pin 7 of the first transformer is connected with a power supply end and is also grounded through a sixth capacitor; the 8 th pin of the first transformer is connected with the 127 th pin of the PHY chip, the 9 th pin of the first transformer is connected with the 4 th pin of the first relay, the 10 th pin of the first transformer is connected with one end of a tenth resistor, the 11 th pin of the first transformer is connected with the 5 th pin of the first relay, the 14 th pin of the first transformer is connected with the 4 th pin of the second relay, the 15 th pin of the first transformer is connected with the other end of the tenth resistor and one end of a seventh capacitor through a ninth resistor, the other end of the seventh capacitor is grounded, and the 16 th pin of the first transformer is connected with the 5 th pin of the second relay; the 4 th pin, the 5 th pin, the 12 th pin and the 13 th pin of the first transformer are all suspended;

the No. 1 pin of the second transformer is connected with the No. 9 pin of the PHY chip, and the No. 2 pin of the second transformer is connected with a power supply end and is grounded through an eighth capacitor; a pin 3 of the second transformer is connected with a pin 8 of the PHY chip, a pin 6 of the second transformer is connected with a pin 12 of the PHY chip, and a pin 7 of the second transformer is connected with a power supply end and is also grounded through a ninth capacitor; a pin 8 of the second transformer is connected with a pin 11 of the PHY chip, a pin 9 of the second transformer is connected with a pin 4 of the third relay, a pin 10 of the second transformer is connected with one end of the twelfth resistor, a pin 11 of the second transformer is connected with a pin 5 of the third relay, a pin 14 of the second transformer is connected with a pin 4 of the fourth relay, a pin 15 of the second transformer is connected with the other end of the twelfth resistor and one end of the tenth capacitor through the eleventh resistor, the other end of the tenth capacitor is grounded, and a pin 16 of the second transformer is connected with a pin 5 of the fourth relay; the 4 th pin, the 5 th pin, the 12 th pin and the 13 th pin of the second transformer are all suspended.

A display system for realizing network loop transmission comprises a control host, a network switch and a plurality of display modules, wherein the display modules are connected in series through a network cable;

the control host outputs a corresponding network signal according to the network video to be displayed, and the network switch outputs the network signal to a display module connected with the network switch; the display module converts the network signal into a network protocol signal and transmits the network protocol signal to the display screen for display, and the display module also outputs the network signal to a subordinate display module connected with the display module.

Compared with the prior art, the display module and the display system for realizing network loop transmission provided by the invention have the advantages that the number of the display modules is multiple, and the display modules are connected in series through the network cable; the control host outputs a corresponding network signal according to the network video to be displayed, and the network switch outputs the network signal to a display module connected with the network switch; the display module converts the network signal into a network protocol signal and transmits the network protocol signal to the display screen for display, and the display module also outputs the network signal to a subordinate display module connected with the display module. The network signal can be displayed on the current display module, and can also be transmitted to other display screens in a loop-through mode for display, a plurality of converters are not needed, the occupied space is small, and the cost is saved; meanwhile, the plurality of display modules are connected in series through the network cable, so that the wiring is very simple and the operation is convenient; thereby the problem that the cost is higher and the wiring is troublesome is shown to current many screens has been solved.

Drawings

Fig. 1 is a block diagram of a conventional multi-screen display system.

Fig. 2 is a block diagram of a display system for implementing network loop transmission according to the present invention.

Fig. 3 is a block diagram of a display module for implementing network loop transmission according to the present invention.

Fig. 4 is a circuit diagram of a first DB-9 interface in a display module provided by the present invention.

Fig. 5 is a circuit diagram of a second DB-9 interface in the display module provided by the present invention.

Fig. 6 is a circuit diagram of a signal relay circuit in a display module provided by the present invention.

Fig. 7 is a circuit diagram of a portion of a network transformer circuit in a display module provided by the present invention.

Fig. 8 is a circuit diagram of another portion of the network transformer circuit in the display module provided by the present invention.

Fig. 9 is a circuit diagram of a PHY chip in a display module according to the present invention.

Detailed Description

The invention provides a display module and a display system for realizing network loop transmission, which are suitable for the condition of multi-screen display. In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 2, the display system for implementing network loop transmission according to the present invention includes a control host 10, a network switch 20, and a plurality of display modules 30 (i.e., a first display module to an nth display module, where N is a positive integer); the control host 10 is connected to the network switch 20 through a network cable, the network switch 20 is connected to a display module through a network cable, and the display modules are connected in series through the network cable. The control host 10 outputs a corresponding network signal according to the network video to be displayed, and the network switch 20 outputs the network signal to the display module connected thereto. The display module converts the network signal into a network protocol signal which can be identified by the display screen and transmits the network protocol signal to the display screen for display, and the network signal is output to a subordinate display module connected with the display module. Therefore, the network signal can be displayed on the current display module, and the network signal can be transmitted to other display screens to be displayed in a loop-through mode. A plurality of converters are not needed, so that the occupied space is small and the cost is saved; meanwhile, the plurality of display modules are connected in series through the network cable, so that the wiring is very simple and the operation is convenient; thereby the problem that the cost is higher and the wiring is troublesome is shown to current many screens has been solved.

In this embodiment, the control host 10 can also set parameters such as an IP address and time of the display module 30, and load the parameters to a network signal in the form of a control signal and transmit the parameters to the corresponding display module through a network cable. The network address can be distributed to the display modules in a centralized manner through the control host, the network signals can be displayed in different display units, the network signals can be completely displayed in each display unit through the network wire loop, the wiring is simple, the operation is convenient, and the cost is reduced.

Referring to fig. 3, the display module 30 includes a loop-through unit 310, a network switching unit 320, a processing unit 330 and an LVDS interface 340; the ring unit 310, the network switching unit 320, the processing unit 330, and the LVDS interface 340 are sequentially connected, and the LVDS interface 340 is externally connected to a display screen. If the display module 30 is the first display module, the loop-through unit 310 is connected to the network switch 20 and the lower display module; if the display module 30 is another display module (any one of the second to nth display modules), the loop unit 310 is connected to the upper display module and the lower display module.

The loop-through unit 310 receives the network signal, outputs the network signal to a lower display module connected thereto when an internal path thereof is cut off, and outputs the network signal to the network switching unit 320 when the internal path thereof is turned on; the network switching unit 320 encodes the network signal and converts the network signal into a network protocol signal which can be identified by the display screen; the network switching unit 320 transmits the network protocol signal to the processing unit 330 for signal processing (including processing of brightness, size, and sharpness of an image, which is a conventional technique), and outputs the signal to the display screen through the LVDS interface 340. The network switching unit 320 also transmits the received network signal to the lower display module through the loop-through unit 310. In this way, no matter whether the internal path of the loop-through unit 310 is on or not, a network signal is output to the lower display module, thereby implementing loop-through input and output of the network signal.

It should be understood that the display module 30 also includes other units, such as a power supply unit, which is a prior art, and the present embodiment only describes the units related to the network loop transmission.

In this embodiment, the loop-through unit 310 includes a first DB-9 interface 311, a second DB-9 interface 312, and a signal relay circuit 313; the signal relay circuit 313 connects the first DB-9 interface 311, the second DB-9 interface 312, and the network switching unit 320. If the display module 30 is a first display module, the first DB-9 interface 311 is connected to a network switch, and the second DB-9 interface 312 is connected to a lower display module; if the display module 30 is another display module (any one of the second to nth display modules), the first DB-9 interface 311 is connected to the upper display module, and the second DB-9 interface 312 is still connected to the lower display module.

The first DB-9 interface 311 receives a network signal and transmits the network signal to the signal relay circuit 313; the signal relay circuit 313 is turned off (corresponding to the internal path being turned off) when power is off, and the output network signal is transmitted to the first DB-9 interface of the lower display module connected thereto through the second DB-9 interface 312, thereby passing the network signal loop. The signal relay circuit 313 is turned on (corresponding to the internal path being turned on) when it is powered on, outputs a network signal to the network switching unit 320, and also transmits the network signal output from the network switching unit to the first DB-9 interface of the lower display module.

It should be understood that each display module has only two DB-9 interfaces, and thus two external network cables are connected correspondingly. In this embodiment, the labels (i.e., the first to nth) of the display modules are only used to describe the connection sequence of the display modules, and the actual position relationship of the display modules is not limited. In specific implementation, if the second display module is connected to the network switch through the network cable, based on the serial relation of the display modules, the second display module is regarded as the first display module, and the first display module is regarded as the last display module and is connected behind the nth display module; or the first display module is directly connected to the network switch. In the loop communication, each unit is connected in series in terms of hardware, and network signals are transmitted and communicated in sequence as long as the units are connected in series. For example, if an office has 10 computers, 10 computers in the prior art need to be connected to a network switch by 1 network cable respectively, so that each computer can surf the internet; if the loop-through of this embodiment is adopted, 10 computers are connected in series by network cables, and only the first or last computer (because the two computers have one network port not connected) needs to be connected to the network switch, so that the internet access function can be realized.

The network switching unit 320 includes a network transformer circuit 321 and a PHY chip 322 (preferably model IP 175C/D); the network transformer circuit 321 is connected to the PHY chip 322 and the signal relay circuit 313, and the PHY chip 322 is connected to the processing unit 330. When the internal path is turned on, the network transformer circuit 321 performs enhancement processing on the input network signal, and the PHY chip 322, on one hand, encodes and converts the processed signal into a network protocol signal that can be recognized by the display screen, and, on the other hand, transmits the processed signal back to the network transformer circuit 321 to be fed back to the signal relay circuit. Specifically, the network transformer circuit 321 functions as: firstly, data is transmitted, differential signals sent by the PHY chip 322 are coupled and filtered by using coils coupled in a differential mode to enhance signals, and the signals are coupled to the other end of the connecting network wire with different levels through conversion of electromagnetic fields; and secondly, isolating different levels among different network equipment connected by the network cable so as to prevent different voltages from transmitting and damaging the equipment through the network cable.

The processing unit 330 is provided with a MAC device and an SCLAER image processing device, and the MAC device and the SCLAER image processing device are integrated together in the embodiment. The PHY chip and the MAC device are contents in the network part. Typically, a PHY is a physical layer, being a physical interface transceiver; the MAC device is a media access controller. The PHY chip encodes and converts the network signal and outputs a network protocol signal, and the network protocol signal is sent to the MAC device through an RMII (standard media independent interface of Ethernet). The network protocol signal is processed by the MAC device and the SCLAER image processing device and then output to the display screen through the LVDS interface 340 for display.

Referring to fig. 4 and 5, the ring-through unit 310 further includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8; the 1 st pin of the first DB-9 interface 311 is connected with the signal relay circuit 313 through a first resistor R1, the 6 th pin of the first DB-9 interface 311 is connected with the signal relay circuit 313 through a second resistor R2, the 2 nd pin of the first DB-9 interface 311 is connected with the signal relay circuit 313 through a third resistor R3, the 3 rd pin of the first DB-9 interface 311 is connected with the signal relay circuit 313 through a fourth resistor R4, the 1 st pin of the second DB-9 interface 312 is connected with the signal relay circuit 313 through a fifth resistor R5, the 6 th pin of the second DB-9 interface 312 is connected with the signal relay circuit 313 through a sixth resistor R6, the 2 nd pin of the second DB-9 interface 312 is connected with the signal relay circuit 313 through a seventh resistor R7, and the 3 rd pin of the second DB-9 interface 312 is connected with the signal relay circuit 313 through an eighth resistor R8. Each signal transmitted by the first DB-9 interface 311 and the second DB-9 interface 312 is denoised by a corresponding resistance current limiting to improve the stability of the signal.

In specific implementation, other pins of the first DB-9 interface 311 and the second DB-9 interface 312 may also be grounded through a resistor, respectively, so as to prevent other pins from being suspended and affecting the stability of the transmitted signal.

Referring to fig. 6, the signal relay circuit 313 includes a first relay U1, a second relay U2, a third relay U3, a fourth relay U4, a first capacitor C1, a second capacitor C2, a third capacitor C3, and a fourth capacitor C4; the model of each relay is G6J-2P-Y-5VDC, and the capacitance values of the first capacitor C1 to the fourth capacitor C4 are all 100 nF.

The 1 st pin of the first relay U1 is connected with a power supply end IN _5V and is also grounded through a first capacitor C1; the 2 nd pin of the first relay U1 is connected with the 1 st pin of the second DB-9 interface 312 through a fifth resistor R5, the 3 rd pin of the first relay U1 is connected with the 1 st pin of the first DB-9 interface 311 through a first resistor R1, the 4 th pin and the 5 th pin of the first relay U1 are both connected with the network transformer circuit 321, the 6 th pin of the first relay U1 is connected with the 2 nd pin of the first DB-9 interface 311 through a third resistor R3, and the 7 th pin of the first relay U1 is connected with the 2 nd pin of the second DB-9 interface 312 through a seventh resistor R7.

The 1 st pin of the second relay U2 is connected with a power supply end IN _5V and is also grounded through a second capacitor C2; the 2 nd pin of the second relay U2 is connected with the 3 rd pin of the second DB-9 interface 312 through an eighth resistor R8, the 3 rd pin of the second relay U2 is connected with the 3 rd pin of the first DB-9 interface 311 through a fourth resistor R4, the 4 th pin and the 5 th pin of the second relay U2 are both connected with the network transformer circuit 321, the 6 th pin of the second relay U2 is connected with the 6 th pin of the first DB-9 interface 311 through a second resistor R2, and the 7 th pin of the second relay U2 is connected with the 6 th pin of the second DB-9 interface 312 through a sixth resistor R6.

The 1 st pin of the third relay U3 is connected with a power supply end IN _5V and is also grounded through a third capacitor C3; the 3 rd pin of the third relay U3 is connected with the 1 st pin of the second DB-9 interface 312 through a fifth resistor R5, the 4 th pin and the 5 th pin of the third relay U3 are both connected with the network transformer circuit 321, and the 6 th pin of the third relay U3 is connected with the 2 nd pin of the second DB-9 interface 312 through a seventh resistor R7.

The 1 st pin of the fourth relay U4 is connected with a power supply end IN _5V and is also grounded through a fourth capacitor C4; the 3 rd pin of the fourth relay U4 is connected with the 3 rd pin of the second DB-9 interface 312 through an eighth resistor R8, the 4 th pin and the 5 th pin of the fourth relay U4 are both connected with the network transformer circuit 321, and the 6 th pin of the fourth relay U4 is connected with the 6 th pin of the second DB-9 interface 312 through a sixth resistor R6.

Referring to fig. 7, 8 and 9, the network transformer circuit 321 includes a first transformer T1, a second transformer T2, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9 and a tenth capacitor C10; the types of the first transformer T1 and the second transformer T2 are both CO-TS8121CLF, the resistances of a ninth resistor R9 to a twelfth resistor R12 are both 75R omega, and the capacitance values of a fifth capacitor C5, a sixth capacitor C6, an eighth capacitor C8 and a ninth capacitor C9 are all 0.1 uF. The capacitance values of the seventh capacitor C7 and the tenth capacitor C10 are both 1 nF.

The 1 st pin of the first transformer T1 is connected to the 4 th pin of the PHY chip 322, and the 2 nd pin of the first transformer T1 is connected to the power supply terminal AVCC and also grounded through a fifth capacitor C5; the 3 rd pin of the first transformer T1 is connected to the 3 rd pin of the PHY chip 322, the 6 th pin of the first transformer T1 is connected to the 128 th pin of the PHY chip 322, the 7 th pin of the first transformer T1 is connected to the power supply terminal AVCC and is also grounded through the sixth capacitor C6; the 8 th pin of the first transformer T1 is connected to the 127 th pin of the PHY chip 322, the 9 th pin of the first transformer T1 is connected to the 4 th pin of the first relay U1, the 10 th pin of the first transformer T1 is connected to one end of a tenth resistor R10, the 11 th pin of the first transformer T1 is connected to the 5 th pin of the first relay U1, the 14 th pin of the first transformer T1 is connected to the 4 th pin of the second relay U2, the 15 th pin of the first transformer T1 is connected to the other end of the tenth resistor R10 and one end of a seventh capacitor C7 through a ninth resistor R9, the other end of the seventh capacitor C7 is grounded, and the 16 th pin of the first transformer T1 is connected to the 5 th pin of the second relay U2; the 4 th, 5 th, 12 th and 13 th legs of the first transformer T1 are all floating.

The 1 st pin of the second transformer T2 is connected to the 9 th pin of the PHY chip 322, and the 2 nd pin of the second transformer T2 is connected to the power supply terminal AVCC and also grounded through the eighth capacitor C8; the 3 rd pin of the second transformer T2 is connected to the 8 th pin of the PHY chip 322, the 6 th pin of the second transformer T2 is connected to the 12 th pin of the PHY chip 322, and the 7 th pin of the second transformer T2 is connected to the power supply terminal AVCC and is also grounded through the ninth capacitor C9; the 8 th pin of the second transformer T2 is connected to the 11 th pin of the PHY chip 322, the 9 th pin of the second transformer T2 is connected to the 4 th pin of the third relay U3, the 10 th pin of the second transformer T2 is connected to one end of the twelfth resistor R12, the 11 th pin of the second transformer T2 is connected to the 5 th pin of the third relay U3, the 14 th pin of the second transformer T2 is connected to the 4 th pin of the fourth relay U4, the 15 th pin of the second transformer T2 is connected to the other end of the twelfth resistor R12 and one end of the tenth capacitor C10 through the eleventh resistor R11, the other end of the tenth capacitor C10 is grounded, and the 16 th pin of the second transformer T2 is connected to the 5 th pin of the fourth relay U4; the 4 th, 5 th, 12 th and 13 th legs of the second transformer T2 are all floating.

Referring to fig. 4 to 9, when the relays (U1-U4) are not turned on (i.e., no voltage is input to the power supply terminal IN _5V from the existing power unit IN the display module 30), the 2 nd pin is connected to the 3 rd pin, and the 6 th pin is connected to the 7 th pin. The network signal is input from the first DB-9 interface 311, passes through the second relay U2, and is output from the second DB-9 interface 312. The signal trend is TX0P/TX0N → TX0+/TX0- → TX1+/TX1- → TX1P/TX1N, RX0P/RX0N → RX0+/RX0- → RX1+/RX1- → RX1P/RX 1N. Wherein, TX0P/TX0N or RX0P/RX0N represents network signals, and the sources are differentiated by T and R.

When each relay (U1-U4) is turned on (power-on, i.e. the power supply terminal IN _5V has a voltage input from the existing power supply unit IN the display module 30), the 3 rd pin is connected with the 4 th pin, and the 5 th pin is connected with the 6 th pin. Taking the network signal TX0P/TX0N as an example, the network signal is input from the first DB-9 interface 311, passes through the second relay U2, is input to the first transformer T1 for enhancement, and is input to the PHY chip 322 (now, it becomes TXOP0/TXOM 0). On one hand, the PHY chip 322 encodes the TXOP0/TXOM0, converts the encoded signal into a network protocol signal which can be identified by a display screen, and outputs the network protocol signal to the processing unit; on the other hand, TXOP0/TXOM0 is named as TXOP1/TXOM1 to be output to a second transformer T2, converted into TXO1+/TXO1 to be output to a fourth relay U4, and then converted into TX1+/TX1 to be output from a second DB-9 interface 312. The signal trend is TX0P/TX0N → TX0+/TX0- → TXO0+/TXO0- → TXOP0/TXOM0 → TXOP1/TXOM1 → TXO1+/TXO1- → TX1+/TX1- → TX1P/TX 1N. RX0P/RX0N can obtain signals going to RX0P/RX0N → RX0+/RX0- → RXI0+/RXI0- → RXIP0/RXIM0 → RXIP1/RXIM1 → RXI1 +/RXII 1- → RX1+/RX1- → RX1P/RX1N in the same way.

When the relay is conducted, RX/TX in the two DB-9 interfaces passes through the relay, the transformer, the PHY chip, the transformer and the relay, and is output from the other DB-9 interface. When the relay is cut off (power is cut off), RX/TX in the two DP-9 interfaces are connected in parallel, and the signals are not transmitted to the transformer after passing through the relay. Through the design of the loop-through (application of the relay), even if some display modules are not electrified or do not work, network signals can be transmitted between the display modules in sequence, and the normal use of other display modules connected with the display modules is not influenced.

In summary, according to the display module and the display system for implementing network loop-through transmission provided by the invention, each display module is connected in series through the DB-9 interface by using the network cable, and the network signals are sequentially transmitted in the series order, so that not only can the network signals be displayed on the current display unit be implemented, but also the network signals can be displayed on other display units through the loop, so that the loop-through of the network signals is implemented, which has no direct relation with whether the current display module is working normally, and the network signals output by the network loop-through can be output to the next display module through the loop-through, thereby truly implementing the passive loop-through function of the network signals. The whole design is practical, the wiring is simple, the operation is convenient, and the application function of the network signal in the display unit is realized. And each display module is not arranged in sequence and can be flexibly connected, and then different display modules are controlled at any time and any place by the control host through a network control mode.

It is to be understood that the invention is not limited to the examples described above, but that modifications and variations may be effected thereto by those of ordinary skill in the art in light of the foregoing description, and that all such modifications and variations are intended to be within the scope of the invention as defined by the appended claims.

Claims

1. A display module for realizing network loop transmission is connected with a display screen and is characterized by comprising a loop unit, a network switching unit, a processing unit and an LVDS interface;

the loop-through unit receives the network signal, outputs the network signal to a lower-level display module connected with the loop-through unit when an internal passage of the loop-through unit is cut off, and outputs the network signal to the network switching unit when the internal passage is switched on; the network switching unit encodes the network signal and converts the network signal into a network protocol signal, and the network switching unit transmits the network protocol signal to the processing unit for signal processing and then outputs the signal to the display screen for display through the LVDS interface; the network switching unit also outputs the input network signal to a lower display module through the loop-through unit;

the loop-through unit comprises a first DB-9 interface, a second DB-9 interface and a signal relay circuit;

2. The display module for realizing network loop transmission according to claim 1, wherein the network switching unit comprises a network transformer circuit and a PHY chip;

3. The display module for realizing network loop-through transmission according to claim 2, wherein the loop-through unit further comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor and an eighth resistor;

4. The display module for realizing network loop-through transmission according to claim 3, wherein the signal relay circuit comprises a first relay, a second relay, a third relay, a fourth relay, a first capacitor, a second capacitor, a third capacitor and a fourth capacitor;

the 1 st pin of the second relay is connected with the power supply end and is grounded through a second capacitor; a pin 2 of the second relay is connected with a pin 3 of the second DB-9 interface through an eighth resistor, the pin 3 of the second relay is connected with a pin 3 of the first DB-9 interface through a fourth resistor, pins 4 and 5 of the second relay are both connected with a network transformer circuit, a pin 6 of the second relay is connected with a pin 6 of the first DB-9 interface through a second resistor, and a pin 7 of the second relay is connected with a pin 6 of the second DB-9 interface through a sixth resistor;

5. The display module for realizing network loop-through transmission according to claim 4, wherein the network transformer circuit comprises a first transformer, a second transformer, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor and a tenth capacitor;

6. A display system for realizing network loop transmission, which comprises a control host and a network switch, and is characterized by further comprising a plurality of display modules according to any one of claims 1 to 5, wherein the plurality of display modules are connected in series through a network cable;