4K ultra-high-definition audio and video application solution based on T630 high-speed interface chip

summary

With the wave of domestic chip replacement and the recent soaring prices of imported FPGA chips, the market is increasingly in need of a domestic USB3.0+FPGA solution to meet the needs of business balance and special function development. The T630 domestic USB3.0 high-speed interface chip independently developed by Fangcun Microelectronics has the characteristics of rich functions, strong performance, and strong scalability. It can perfectly adapt to many electronic products such as video capture cards and video conferencing cameras. In particular, it provides source code-level solution support for audio and video acquisition, which can help customers shorten product development cycles, reduce overall development costs, and enhance product market competitiveness.

0. Background

In the past few years, the USB3.0 audio and video capture card solutions were basically implemented with foreign main control chips such as CYUSB3014. With the popularity of the live broadcast industry in recent years, the performance and function requirements are increasing. At the same time, with the wave of domestic chip replacement and the recent soaring prices of imported FPGA chips, the market is increasingly in need of a domestically produced USB3.0+FPGA solution to meet the needs of business balance and special function development.

1. Introduction of T630 domestic USB3.0 high-speed interface chip

1.1 Basic information of the chip

Machine vision requires real-time transmission of massive amounts of data, so the development of the industry cannot be separated from the support of high-speed interface controllers. The T630 chip is a purely domestically produced USB3.0 ultra-high-speed controller independently developed by Fangcun Microelectronics. It has the characteristics of rich functions, strong performance, and strong scalability. It can be widely used in video capture cards, industrial capture cards, printers, scanners, digital cameras, measurement and acquisition equipment and many other electronic products.

The chip integrates a domestically produced 32-bit high-performance RISC CPU, supports multiple interfaces such as USB3.0, MUXIO, I2C, SPI, UART, etc., can quickly communicate with FPGA/CPU on the embedded motherboard, and can be used as a USB3.0 expansion chip to achieve data transmission with PC or server. It is worth mentioning that the transmission performance of the T630 high-speed interface chip is 20% higher than the industry benchmark, and the cost performance is 30% better than the industry benchmark, breaking the market monopoly of European and American manufacturers for ten years.

T630 chip appearance

(10mmx10mm, BGA package, industrial grade)

1.2 Chip Internal Architecture

1.3 T630 core value:

Independent and controllable pure localization breaks the long-term monopoly of Europe and the United States

Industrial temperature range, large-scale commercial production

Localized and efficient support, customized services for major customers

Continuous cost optimization and reliable supply guarantee

1.4 Chip Product Features

System resources

Integrated 32-bit domestic CPU CK803S; maximum operating frequency 200MHz

CK803S has built-in 16KB I/D Cache and 32KB DTCM

32KB ROM; 256KB SRAM; 8KB SRAM (system dedicated) 512KB/1MB on-chip Flash

Communication interface

Supports 1 USB3.0 Device, interface rate 5Gbps, backward compatible with USB2.0/USB1.1, supports control/batch/interrupt/isochronous transmission types

The MUXIO interface supports a maximum data width of 32 bits, a maximum interface frequency of 120MHz, and supports four working modes: FIFO Slave, FIFO Master, SRAM Master, and ADMUX Master.

The I2C interface supports Standard, Fast and Fast+ modes; supports HS-mode; supports master-slave mode

UART interface is fully compatible with high-speed NS 16C550A UART; maximum baud rate is 3Mbit/s; integrated 32bytes TX/RX FIFO

SPI interface supports master-slave mode; supports interrupt and query mode

Additional Resources

Built-in hardware DMA

Built-in POR (Power on Reset) circuit

Built-in 8 timers

Built-in interrupt controller

Built-in 1 watchdog

Package type: BGA121

Package size: 10.0mm*10.0mm*0.8mm

T630 Development and Evaluation Board

(Welcome to apply for a trial through Fangcun's official website and WeChat account)

2. T630 high-speed interface chip

4K Ultra High Definition Audio and Video Capture Application Solution

2.1 Basic information of the solution

This solution is a USB3.0 developed by Fangcun Microelectronics, integrating 4KP30 video, audio input acquisition + audio output and other functions, and is an independent and controllable domestic chip replacement solution. It consists of Fangcun T630 (USB3), domestic FPGA, HDMI RX, sound Codec and other chips. The overall block diagram is shown in the figure below.

Codec: Convert digital to analog sound signals

RX: HDMI input video format converted to TTL signal

FPGA: collects audio and video signals output by RX, and sends them to T630 as UVC/UAC packets

T630: responsible for UVC/UAC protocol data transmission, device enumeration and handshake control

Basic functions:

USB3.0/2.0 Device Dual Mode

Compliant with UVC1.0+UAC1.0 protocol

HDMI 1.4b standard input, UVC video equipment supports up to 3840*2160@30Hz output

Device enumeration supports 24 different resolutions in formats such as YUY2, RGB24, and NV12, and supports adding and deleting

Audio 2-way input (RX+MIC) + 1-way output (Headphone), 48000 16-bit sampling

Compatible with Windows, Android, Linux, MacOS and other systems, and adapted to system cameras, skype, DingTalk and other APPs

The host computer can upgrade the device firmware online

2.2 Data processing flow

As shown in the figure above, the USB Device in this data path is the T630 front end, which establishes a physical connection with the Host and mainly completes the interactive processing of the UVC protocol and the uplink and downlink data transmission; Muxio is responsible for receiving and sending data on the FPGA side, a 32-bit parallel bus with a maximum operating frequency of 120 MHz, similar to the GPIF bus, with the main difference being the different ep channel expressions, and the T630 DMA mode is divided into high-speed and low-speed modes. The low-speed mode data is buffered in SRAM, while the high-speed mode buffers in DTCM, which are suitable for transmitting audio and video data respectively.

If you want to complete the transmission of 4KP30 audio and video data, the bandwidth requirement for MUXIO is very high. The actual verification fully meets the requirements of NV12 4KP3. The following is the throughput test of T630 4-channel batch transmission mode:

As can be seen from the above figure, the highest transfer rate per second is 411.55MB/S, the average transfer rate per second is 410.88MB/S, and the lowest transfer rate per second is 405.13MB/S. The above has passed the 7*24 hours stability test.

2.3 Demonstration Overview

After the USB cable is plugged into the host, the device manager will enumerate and identify 1 camera device + 3 audio devices as above.

The supported video formats and resolutions are listed in the camera device format column of potplayer.

The video and audio capture settings column in OBS will also display the video format and resolution supported by the device.

3. Conclusion

This article mainly introduces the application of T630 high-speed USB3.0 interface chip in 4K ultra-high-definition audio and video acquisition and its data processing flow, etc., to meet the market demand for domestic USB3.0+FPGA solutions. Fangcun Microelectronics will always adhere to the market as the leader, talent as the foundation, and the development of integrated circuit chips with independent intellectual property rights as the basis, continue to innovate, rely on technological advantages, continuously improve product quality, create more value for customers, and promote the rapid development of machine vision and automation industries.