There are many kinds of mobile phone charging cables that are not universal on the market now. The end of the charging cable connected to the mobile phone mainly has three interfaces, Android mobile phone, Apple mobile phone and old mobile phone. Their names are USB-Micro, USB-C and USB-lightning. At the end of the charging head, the interface is divided into USB-C and USB Type-A. It has a square shape and cannot be inserted forward and backward.
The video interface on the projector is mainly divided into HDMI and old-fashioned VGA; on the computer monitor, there is also a video signal interface called DP (Display Port).
In September this year, the European Commission announced a new legislative proposal, hoping to unify the charging interface types of portable electronic devices such as smartphones and tablet computers within two years, and the USB-C interface will become a common standard for electronic devices in the EU. In October, Greg Joswiak, Apple’s vice president of worldwide marketing, said in an interview that Apple would “have to” use the USB-C port on the iPhone.
At this stage, when all interfaces are unified into USB-C, we may face an problem-the standard of USB interface is too messy!
In 2017, the USB interface standard was upgraded to USB 3.2, and the latest version of the USB interface can transmit data at a rate of 20 Gbps-this is a good thing, but
l Rename USB 3.1 Gen 1 (that is, USB 3.0) to USB 3.2 Gen 1, with a maximum rate of 5 Gbps;
l Renamed USB 3.1 Gen 2 to USB 3.2 Gen 2, with a maximum rate of 10 Gbps, and added USB-C support for this mode;
l The newly added transmission mode is named USB 3.2 Gen 2×2, with a maximum rate of 20 Gbps. This mode only supports USB-C and does not support the traditional USB Type-A interface.
Later, the engineers who formulated the USB standard felt that most people could not understand the USB naming standard, and added the naming of the transmission mode.
l USB 1.0 (1.5 Mbps) is called Low Speed;
l USB 1.0 (12 Mbps) called Full Speed;
l USB 2.0 (480 Mbps) called High Speed;
l USB 3.2 Gen 1 (5 Gbps, formerly known as USB 3.1 Gen 1, formerly known as USB 3.0) is called Super Speed;
l USB 3.2 Gen 2 (10 Gbps, formerly known as USB 3.1 Gen 2) is called Super Speed+;
l USB 3.2 Gen 2×2 (20 Gbps) has the same name as Super Speed+.
Although the name of the USB interface is very confusing, its interface speed has been improved. USB-IF has plans to allow USB to transmit video signals, and they plan to integrate Display Port interface (DP interface) into USB-C. Let the USB data cable truly realize one line to transmit all signals.
But USB-C is just a physical interface, and it is not certain what signal transmission protocol is running on it. There are several versions of each protocol that can be transmitted on USB-C, and each version has more or less differences:
DP has DP 1.2, DP 1.4 and DP 2.0 (now DP 2.0 has been renamed DP 2.1);
MHL has MHL 1.0, MHL 2.0, MHL 3.0 and superMHL 1.0;
Thunderbolt has Thunderbolt 3 and Thunderbolt 4 (data bandwidth of 40 Gbps);
HDMI only has HDMI 1.4b (the HDMI interface itself is also very confusing);
VirtualLink also only has VirtualLink 1.0.
Moreover, USB-C cables do not necessarily support all of these protocols, and the standards supported by computer peripherals vary.
On October 18 this year, USB-IF finally simplifies the way USB is named this time.
USB 3.2 Gen 1 is renamed to USB 5Gbps, with a bandwidth of 5 Gbps;
USB 3.2 Gen 2 is renamed to USB 10Gbps, with a bandwidth of 10 Gbps;
USB 3.2 Gen 2×2 is renamed to USB 20Gbps, with a bandwidth of 20 Gbps;
The original USB4 was renamed USB 40Gbps, with a bandwidth of 40 Gbps;
The newly introduced standard is called USB 80Gbps and has a bandwidth of 80 Gbps.
USB unifies all interfaces, which is a beautiful vision, but it also brings an unprecedented problem – the same interface has different functions. One USB-C cable, The protocol running on it may be Thunderbolt 4, which was launched only 2 years ago, or it may be USB 2.0 more than 20 years ago. Different USB-C cables may have different internal structures, but their appearance is almost the same.
Therefore, even if we unify the shape of all computer peripheral interfaces into USB-C, the Babel Tower of computer interfaces may not be truly established.
Post time: Dec-17-2022
