Tmds-arinc818 video conversion device

Abstract

The utility model discloses a TMDS - ARINC818 video conversion device contains connector, TMDS video signal channel, RGB - ARINC818 mutual unit, ARINC818 video signal channel and optical module, wherein, TMDS video signal channel contains four -channel high -speed differential switch, TMDS decoding unit, TMDS coding unit, and four -channel high -speed differential switch switches the input mode of DVI / HDMI video signal interface on the connector and then is coded and decoded by TMDS decoding unit, TMDS coding unit, and each way ARINC818 video signal channel contains single -channel high -speed differential switch, and single -channel high -speed differential switch switches ARINC818 video telecommunication signal input output mode. The transmission direction of video signal in the utility model can change freely according to the application scene, can adapt to the application demand of 16 kinds of scenes, and the application scene is extensive.

Description

Technical Field

[0001] This utility model belongs to the field of electronic engineering and relates to the use of TMDS signals and ARINC818 signals. Background Technology

[0002] In April 1999, to meet the demands of high-quality graphics and images in the digital age, the Digital Display Working Group (DDWG) launched an interface called DVI (Digital Visual Interface) based on patented technology from Silicon Image, Inc. This aimed to unify the standards for digital display interfaces in the new era. This technology received widespread support from major IT companies such as Intel, Dell, HP, IBM, and Microsoft, leading to its rapid adoption in computer display output. However, with the development of digital high-definition audio-visual technology, the DVI interface began to reveal various problems, failing to meet the industry's needs. For example, the DVI interface could only transmit image signals and did not support audio signal transmission; it was also bulky and inefficient. Therefore, the High Definition Multimedia Interface (HDMI) was developed. HDMI is a fully digital video and audio transmission interface capable of transmitting uncompressed video and audio signals.

[0003] TMDS (Transition Minimized Differential Signal), also known as minimized transmission differential signal, refers to a signal that is converted into 10 bits using XOR and XOR NOT logic encoding algorithms. The first 8 bits are obtained from the original signal after processing, the 9th bit indicates the processing method, and the 10th bit corresponds to DC-balanced signal transmission. The converted data is transmitted differentially. This encoding algorithm reduces the overshoot and undershoot during the signal transition, making the transmitted data closer to DC balance, reducing electromagnetic interference to the transmission line, and improving signal transmission speed and reliability. TMDS signals have 4 channels: the first 3 channels are for RGB signal transmission, and the 4th channel is for clock signal transmission, ensuring the uniform timing required for RGB signal transmission. Both DVI and HDMI video interfaces use TMDS signals for data transmission.

[0004] Fiber optic transmission, which uses optical fibers as a medium for data and signal transmission, has been increasingly widely used in various fields in recent years, from military equipment to home broadband, from automotive electronics to mobile communications. Its popularity is increasing, and optical signals are becoming more and more favored due to their high bandwidth and good anti-interference capabilities. The ARINC818 signal is a fiber optic digital video signal used in the aerospace field for real-time high-definition video transmission between aerospace equipment. It adopts high-speed serial communication technology to meet the video transmission needs of complex aerospace systems.

[0005] In aerospace equipment, there are many scenarios where TMDS signals and ARINC818 signals coexist. For example, on the C919 large passenger aircraft, the DVI video signal output by the HUD head-up display needs to be converted into an ARINC818 video signal before transmission. On the AG600 rescue aircraft, the ARINC818 video signal output by the WXR weather radar needs to be converted into a DVI video signal before decoding and overlay processing. Therefore, in the aerospace field, there will inevitably be a need for mutual conversion between TMDS signals and ARINC818 signals.

[0006] like Figure 1 The diagram shows three common TMDS-ARINC818 video converters. The first type can convert 4 DVI / HDMI video signals into 4 ARINC818 video signals. The second type can convert 4 ARINC818 video signals into 4 DVI / HDMI video signals. The third type can convert 2 DVI / HDMI video signals into 2 ARINC818 video signals and simultaneously convert 2 ARINC818 video signals into 2 DVI / HDMI video signals.

[0007] While the above three conversion devices can achieve mutual conversion between TMDS signals and ARINC818 signals, they have the following drawbacks:

[0008] 1. The first and second types of devices can only achieve unidirectional signal conversion, which is limited in function and cannot meet the application needs of various different scenarios.

[0009] 2. Although the third method can achieve bidirectional signal conversion, the number of channels is limited, which cannot meet the application needs of various different scenarios.

[0010] 3. Each device has a fixed function. In order to meet specific target requirements, it is often necessary to combine multiple devices. For example, if it is necessary to convert 3 DVI to ARINC818 signals and 1 ARINC818 to DVI signals, then a combination of two conversion devices is required.

[0011] 4. The use of multiple devices in combination often leads to redundant waste of resources, increased costs, increased power consumption, and increased space requirements, which inevitably increases the design difficulty of the system and reduces its reliability. Utility Model Content

[0012] The purpose of this invention is to provide a TMDS-ARINC818 video converter, in which the transmission direction of the video signal can be freely changed according to the application scenario, and can adapt to the application needs of 16 different scenarios.

[0013] The objective of this invention is achieved through the following technical solution:

[0014] A TMDS-ARINC818 video converter includes a connector, four TMDS video signal channels, an RGB-ARINC818 conversion unit, four ARINC818 video signal channels, and an optical module.

[0015] The connector includes four DVI / HDMI video signal interfaces, each of which is configured with one TMDS video signal channel;

[0016] Each TMDS video signal channel includes a four-channel high-speed differential switch, a TMDS decoding unit, and a TMDS encoding unit. The four-channel high-speed differential switch switches the input and output modes of the DVI / HDMI video signal interface. When the DVI / HDMI video signal interface is in input mode, the TMDS decoding unit decodes the input TMDS signal and outputs the digital RGB video to the RGB-ARINC818 converter unit. When the DVI / HDMI video signal interface is in output mode, the TMDS encoding unit encodes the digital RGB video input to the RGB-ARINC818 converter unit and outputs the TMDS signal to the DVI / HDMI video signal interface.

[0017] The RGB-ARINC818 conversion unit completes the conversion between digital RGB video and high-speed serial ARINC818 video electrical signals;

[0018] Each ARINC818 video signal channel includes a single-channel high-speed differential switch, which switches between the ARINC818 video electrical signal input and output modes.

[0019] The optical module completes the conversion between optical and electrical signals of the ARINC818 video signal.

[0020] The beneficial effects of this utility model are as follows:

[0021] 1. The transmission direction of the video signal in this utility model can be freely changed according to the application scenario, and it can adapt to the application needs of 16 scenarios, with a wide range of applications.

[0022] 2. The flexible configuration of video signals in this utility model enables a single device to meet the application needs of multiple scenarios without the need for a combination of multiple devices, thus saving costs, reducing power consumption, lightening weight, and shrinking size.

[0023] 3. This utility model has a simple design, is easy to implement, and has good engineering applicability. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of three common TMDS-ARINC818 video converters.

[0025] Figure 2 This is a structural diagram of a TMDS-ARINC818 video conversion device according to the present invention.

[0026] Figure 3 This is a schematic diagram illustrating the implementation principle of a TMDS-ARINC818 video converter according to this utility model.

[0027] Figure 4 This is the schematic diagram of the HD3SS3412 four-channel high-speed differential switch.

[0028] Figure 5 This is the schematic diagram of the HD3SS3411 single-channel high-speed differential switch. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0030] The video conversion unit (VCM) is an essential component of the integrated display unit (IDU) in civil aircraft, responsible for converting between DVI video signals and ARINC818 optical video signals. Figure 2 As shown in the figure, the TMDS-ARINC818 video converter shown in this embodiment includes a connector, four TMDS video signal channels, an RGB-ARINC818 conversion unit, four ARINC818 video signal channels, and an optical module.

[0031] The connector contains four DVI / HDMI video signal interfaces, each of which is configured with one TMDS video signal channel.

[0032] Each TMDS video signal channel includes a four-channel high-speed differential switch, a TMDS decoding unit, and a TMDS encoding unit. The four-channel high-speed differential switch switches the input and output modes of the DVI / HDMI video signal interface. When the DVI / HDMI video signal interface is in input mode, the TMDS decoding unit decodes the input TMDS signal and outputs the digital RGB video to the RGB-ARINC818 converter unit. When the DVI / HDMI video signal interface is in output mode, the TMDS encoding unit encodes the digital RGB video input from the RGB-ARINC818 converter unit and outputs the TMDS signal to the DVI / HDMI video signal interface.

[0033] The RGB-ARINC818 conversion unit is the core of this device, which completes the conversion between digital RGB video and high-speed serial ARINC818 video electrical signals.

[0034] Each ARINC818 video signal channel includes a single-channel high-speed differential switch, which switches between the ARINC818 video electrical signal input and output modes.

[0035] The optical module completes the conversion between optical and electrical signals of the ARINC818 video signal.

[0036] The TMDS-ARINC818 video converter shown in this embodiment has four DVI video signal channels and four ARINC818 video optical signal channels. The signal direction "DVI / HDMI → ARINC818" or "DVI / HDMI ← ARINC818" can be arbitrarily set according to project requirements. Therefore, for example... Figure 3 As shown, the video conversion device (VCM) can be divided into five functional units: TMDS input / output switching, TMDS encoding / decoding, RGB-ARINC818 mutual conversion, ARINC818 input / output switching, and photoelectric / electro-optical conversion.

[0037] a) TMDS input / output switching

[0038] The TMDS input / output switching function enables input / output switching between DVI / HDMI video. Since each DVI / HDMI video stream contains four sets of TMDS differential pairs, we use TI's "HD3SS3412" chip to implement the TMDS input / output switching function. Figure 4As shown, it is a four-channel high-speed differential switch that supports data transmission at a rate of 12Gbps. Table 1 shows the function truth table of the "HD3SS3412" chip. The connection relationship of the four differential channels is selected simultaneously according to the high and low levels of "SEL_VI". Therefore, one "HD3SS3412" chip can realize the input and output switching of one DVI / HDMI video.

[0039] Table 1 Truth Table of HD3SS3412 Functions

[0040]

[0041] The TMDS input / output switching unit contains four independent "HD3SS3412" chips, enabling arbitrary switching of input and output for four DVI / HDMI video channels.

[0042] b) TMDS encoding and decoding

[0043] The DVI / HDMI decoding chip uses TI's "TFP401", which is a receiver chip that supports the DVI 1.0 standard. It can convert differential TMDS signals into digital RGB signals for output, with a 24-bit RGB pixel format and a maximum pixel rate of 165MHz.

[0044] The DVI / HDMI encoding chip uses TI's "TFP410", which is a transmitter chip that supports the DVI 1.0 standard. It can convert input digital RGB signals into differential TMDS signals for output. The input pixel format is 24-bit RGB, and the maximum pixel rate supports 165MHz.

[0045] c) RGB-ARINC818 conversion

[0046] The RGB-ARINC818 conversion is implemented using an FPGA. The FPGA is Microsemi's "MPF300T-1FCG484IAV99", which is a PolarFire series FPGA manufactured by Microsemi. It belongs to the fifth generation of Microchip FPGA family and is manufactured using a 28nm process. It has good cost performance and low power consumption among mid-scale FPGAs. It integrates a low-power 12.7Gbps high-speed SerDes port to meet the requirements of 8 inputs and 8 outputs. The FPGA contains 244 available I / O pins to meet the input and output requirements of general digital signals.

[0047] A 24-bit RGB signal (plus a 1-bit clock CLK signal, a 1-bit horizontal synchronization HS signal, a 1-bit vertical synchronization VS signal, and a 1-bit data enable DE signal) is introduced into the FPGA's I / O pins, and the ARINC818 signal is introduced into the FPGA's high-speed Serdes port. The RGB-ARINC818 mutual conversion can be realized through the FPGA logic.

[0048] The channel selection control of the high-speed differential switch is also completed by the FPGA. The FPGA outputs discrete signals to the four-channel high-speed differential switch to control the TMDS input-output switching, and the FPGA outputs discrete signals to the single-channel high-speed differential switch to control the ARINC818 input-output switching.

[0049] d) ARINC818 Input / Output Switch

[0050] This implementation uses the ARINC818 input / output switch to switch the input and output of ARINC818 video signals. Since each ARINC818 video signal contains one differential pair, we use TI's HD3SS3411 chip to implement the ARINC818 input / output switching function. Figure 5 As shown, it is a single-channel high-speed differential switch that supports data transmission at a rate of 10Gbps. Table 2 shows the function truth table of the "HD3SS3411" chip. The connection relationship of a single differential channel is selected according to the high and low levels of "SEL_A818". Therefore, one "HD3SS3411" chip can realize the input and output switching of one ARINC818 video.

[0051] Table 2 HD3SS3411 Function Truth Table

[0052]

[0053] The ARINC818 input / output switching unit contains four independent "HD3SS3411" chips, enabling arbitrary switching of input and output for four ARINC818 video channels.

[0054] e) Photoelectric / electro-optical conversion

[0055] The differential ARINC818 video signal is an electrical signal, while the video conversion device (VCM) outputs an ARINC818 optical video signal. Therefore, photoelectric / electro-optical conversion of the ARINC818 signal is required. The COTSWORKS "RCP-5G-SX" chip is used to achieve this conversion. This chip supports data transmission at a rate of 5Gbps and uses an ARINC801 fiber optic interface, allowing for easy and quick installation and removal from the matching mounting base (the mounting base is soldered onto the PCB, and the "RCP-5G-SX" chip has a built-in connector for docking with the mounting base). As shown in Table 3, xx represents the suffix, and the three different suffixes correspond to three working modes of optical signal transmission: 2 transmit / 2 receive, 4 transmit, and 4 receive.

[0056] Table 3. RCP-5G-SX-xx Function Overview

[0057] 1 DX ARINC818 signal: 2-channel transmit, 2-channel receive 2 TX ARINC818 signal 4-channel transmission 3 RX ARINC818 4-channel signal receiver

[0058] Therefore, by conveniently and flexibly replacing the “RCP-5G-SX” chip with different suffixes, three different functions can be achieved.

[0059] It is understood that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of this utility model, and all such substitutions or changes should fall within the protection scope of the appended claims of this utility model.

Claims

1. A TMDS-ARINC818 video converter, comprising a connector, four TMDS video signal channels, an RGB-ARINC818 conversion unit, four ARINC818 video signal channels, and an optical module, characterized in that: The connector includes four DVI / HDMI video signal interfaces, each of which is configured with one TMDS video signal channel; Each TMDS video signal channel includes a four-channel high-speed differential switch, a TMDS decoding unit, and a TMDS encoding unit; the four-channel high-speed differential switch switches the input and output modes of the DVI / HDMI video signal interface; the TMDS decoding unit decodes the input TMDS signal when the DVI / HDMI video signal interface is in input mode and outputs the digital RGB video to the RGB-ARINC818 conversion unit. When the DVI / HDMI video signal interface is in output mode, the TMDS encoding unit encodes the digital RGB video input from the RGB-ARINC818 conversion unit and outputs the TMDS signal to the DVI / HDMI video signal interface. The RGB-ARINC818 conversion unit completes the conversion between digital RGB video and high-speed serial ARINC818 video electrical signals; Each ARINC818 video signal channel includes a single-channel high-speed differential switch, which switches between the ARINC818 video electrical signal input and output modes. The optical module completes the conversion between optical and electrical signals of the ARINC818 video signal.

2. The TMDS-ARINC818 video conversion device according to claim 1, characterized in that... The four-channel high-speed differential switch uses TI's "HD3SS3412" chip.

3. The TMDS-ARINC818 video conversion device according to claim 1, characterized in that... The TMDS decoding unit uses TI's "TFP401" chip, and the TMDS encoding unit uses TI's "TFP410" chip.

4. The TMDS-ARINC818 video conversion device according to claim 1, characterized in that... The RGB-ARINC818 conversion unit is implemented using an FPGA, specifically Microsemi's "MPF300T-1FCG484IAV99". The input / output modes of the single-channel high-speed differential switch and the four-channel high-speed differential switch are also controlled via the FPGA.

5. The TMDS-ARINC818 video conversion device according to claim 1, characterized in that... The single-channel high-speed differential switch uses TI's "HD3SS3411" chip.

6. The TMDS-ARINC818 video conversion device according to claim 1, characterized in that... The optical module uses COTSWORKS' "RCP-5G-SX" chip.

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