Preface

USB interface plays an irreplaceable role in short-distance hardware communication and hardware power supply, and our quality of life has also been improved in the new technology. Coupled with the popularity of USB Type-C technology, USB has once again stood on the forefront of the wind and waves.

For this reason, this paper mainly analyzes and explains the development process of USB, the line sequence diagram of USB 4.0, the advantages of USB4.0 and so on.

Development of USB technology

USB 1.0

The transmission speed of USB1.0 is only 1.5Mb/s. Through the efforts of technicians for hundreds of days and nights, the version of USB1.0 was upgraded to USB1.1 in 1998, and the speed is also greatly increased to 12Mbps, that is, the transmission rate is 1.5MB/s.

USB 2.0

The transmission speed of USB2.0 reaches 480Mbps, that is, the driver of 60MB Universe USB 2.0 can drive USB1.1 and is compatible with USB1.1.

For our R & D engineers, in the process of designing and developing USB2.0 hardware interface products, the main difficulty lies in: need to master the complex USB2.0 protocol, develop their own USB device driver, and also need to know the corresponding ARM, FPGA, Linux and other programming.

USB 3.0

Under perfect conditions, the limit transmission rate of USB3.0 is 5.0Gbps, but it can only reach 80% of the limit state value in daily life, which is equivalent to 10 times the limit transmission rate of USB 2.0. The transmission rate increases significantly.

USB3.0 uses 8b/10b coding in the physical layer, so the ultimate transmission rate calculated is 4Gbps, which is even less than the transmission rate in the real environment.

USB 4.0

The USB4.0 protocol was released in 2019. In terms of hardware interface, the latest generation of USB4.0 adopts the hardware interface of Type-C. In essence, it uses Intel’s Lightning 3 (Thunderbolt3) technology, also supports the USB standard, and is compatible with Thunderbolt3, USB3.2, USB3.1 and USB2.0 protocols.

With the development of all kinds of mobile devices to lightweight and portable, plus USB4. 0 also uses the Type-C interface, and the future device interface selection direction will uniformly adopt the Type-C interface of USB4.0 protocol.

After more than 20 years of development, USB has been promoted from the original 1.5Mbps of USB1.0 to the 40Gbps of today’s USB4.0.

The future hardware device interface will use the current Type-C interface, which has rich interface resources to meet the needs of our various application scenarios.

Advantages of USB4.0

Fast transmission speed.

Small in size.

Stronger power supply capacity.

More scalable and richer interfaces.

Conclusion

In the days of rapid progress in science and technology, USB has been seen everywhere in our lives. It brings us great convenience. Whether it is USB3.0, which is still in use, or USB2.0 is being phased out, they all carry the changing needs of people.

In the data transmitted through USB, whether it is generating data at work or recording video clips and photos of life, all truly witness the development of the times.