A rather serious problem is that when a technology reaches a performance that allows us to use it normally on a daily basis and without complications, then it becomes acceptable to the public and any progressive improvement ends up being abandoned. The clearest case is that of USB 2.0, a port which over time has become completely obsolete, but which continues to hold its own.
Why should USB 2.0 disappear?
The number of external ports that we use if we have a desktop computer or a laptop does not vary, since we generally call those that we use to connect peripherals to it that way. The problem comes when you see a large number of USB ports on many motherboards, so much so that it’s huge. Where does it come from? Many are derivatives of the D+ and D- pins of USB 3rd generation and up. However, if we remove the mouse and keyboard, we will find that a number of devices do not work well with the slow speed of USB 2.0.
What are we referring to?
- External web cameras.
- SSD and USB hard drives.
- Video capture for streaming.
- Video cameras for video editing.
In fact, of all that we connect to our PC, the USB 2.0 port is only enough for mouse, keyboard, gamepads and headphones. And the paradox is that it far exceeds what is needed for this type of device in terms of bandwidth, but it is deficient in elements such as latency that said interface adds. Obviously 1 millisecond is negligible, but in some applications it is not and a variant of said port with the lowest possible latency is needed, it may not be that we continue with an interface from 20 years ago years without changes.
A possible replacement: optical interfaces
A mouse requires at most, and we exaggerate, about 10 Kbps to operate, since it is its internal circuit that calculates the position and then sends the coordinates to the PC. However, the latency is 1 millisecond. The reason? Well, the resistance made by the wiring adds delay. This is due to a phenomenon called RC Delay, which could be translated as Electrical Resistance and Capacitance Delay, and both can be defined as follows:
- Resistance is the difficulty with which an electrical signal travels through a certain material.
- Capacitance is the ability of a material to hold an electrical charge.
So the problem is not the interface, but the wiring and that’s why it would be much better to use a version in which the USB data pin will use fiber optics. However, this was not done and was never considered. In any case, this was not done because, for example, the optical or SP/DIF port only emits in one direction. Which would make it ideal for a mouse and keyboard, but not for speaker controls and not for headphones with a microphone. This without excluding the need to power the same device from the same interface. Therefore, a very low latency interface is required for some devices.
How would this affect apps?
The benefit would be mostly in games, especially those that require high bitrates, to reduce the time input data is obtained from peripherals, i.e. when pressing on a key, moving or clicking the mouse, etc. If we are talking about games running at 30 FPS, 1ms is a very small percentage of the 33ms needed to generate a frame, but if we are playing at 120Hz and with the same frame rate, 1ms of 8ms is a time much higher.
While our daily use wouldn’t affect it, in games we would see a slight performance boost by eliminating the RC Delay issue that plagues USB 2.0 interfaces. So much so that there are radio frequency adapters for wireless mice and keyboards that have less latency than wired devices.