What Is a USB Host Controller Driver?

Helen Akers

A USB host controller driver controls the way that peripheral devices communicate with a computer's main system. The driver establishes contact between a USB device, such as a keyboard or printer, and ensures that the computer's operating system recognizes it. Many operating systems communicate directly with a USB host controller driver to ensure that computer users do not have to install individual drivers for each device.

A USB cable.
A USB cable.

Universal serial bus (USB) devices all communicate with a computer's operating system through a standard programming language. The majority of the time, a USB host controller driver will interact with C++ or ANSI programming. When a computer user plugs a USB device, such as a cable modem, into one of the ports, the operating system automatically recognizes the device. Depending upon the system, it may automatically install device drivers, enabling operation.

USB cables are used to connect devices -- such as printers, keyboards and music players -- to computers.
USB cables are used to connect devices -- such as printers, keyboards and music players -- to computers.

Standard USB devices, such as a mouse and keyboard, will typically be automatically recognized by a computer's USB host controller driver. Some USB control protocol will combine or bundle the communication process of several standard devices. This helps create efficiency when data needs to be simultaneously transferred. For example, computer users often input data from a keyboard and mouse within a word processing program at the same time.

With bundling, the USB host controller driver may get the computer to communicate with several devices through one communication port. The reality is that each of these devices appears to be plugged into different ports on the hardware's interface. Within the programming language is the direction for the computer to recognize both inputs as belonging to the same port. The driver may also be responsible for redirecting power from the main system through the USB cables that run to each separate device.

In the majority of cases, the USB host will determine how each device receives its power. Some USB protocol allows devices to be connected and disconnected while the computer is on. Other programming interfaces require that the computer be powered off and then rebooted before it will recognize a USB device. The SCSI interface is one protocol that will not allow users to simply "plug and play."

Data transmission speeds and bandwidth are also controlled by a USB host driver. Some drivers support hi-speed transmissions while others only work in a low-speed environment. There are some USB host controller drivers that work exclusively with video and audio devices that need the guarantee of a certain bandwidth.

Many controllers are backward compatible, so a USB 3.0 device can be used in a USB 2.0 port.
Many controllers are backward compatible, so a USB 3.0 device can be used in a USB 2.0 port.

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Discussion Comments


@hamje32 - I’d like to offer up a word of caution about drivers since you mentioned downloading them from the Internet.

There are some websites I’ve found online that purport to offer drivers for Windows XP (or other flavors of Windows I suppose). These are third party websites.

Personally, I wouldn’t recommend that you download drivers from these sites. Yes, they may work, but these are not official sites, so unwittingly you may find yourself downloading a virus as well.

If you need an official driver, go to the Microsoft website – assuming it’s a Microsoft driver – or go to the original manufacturer’s website. They will usually have pages where you can download the drivers that you need.


@hamje32 - The new standard now is USB 3.0; supposedly it’s very fast from what I understand.

In that case you would need the USB 3.0 host controller driver. I don’t have USB 3.0 myself but I understand that it’s found on the newer notebooks and is backward compatible with USB 2.0.


@miriam98 - Yeah, I’ve been there. What’s good about the USB devices however is that once you plug them in, they should immediately try to initialize and load the driver for the device.

Sometimes the driver exists in your operating system; at other times it needs to be downloaded from the Internet or installed from a CD.


If you ever run into problems using a USB host controller, I would check your Windows Device Manager. There you will see a listing of USB devices.

If your list includes a lot of icons that show up as question marks, you know that is where your problem is. You should right click each one of these icons and select uninstall USB device.

Do it until they are all gone. Then you should reboot your computer and reinstall your hi speed USB host controller driver for the device that you want to use.

I’ve done this several times myself. Sometimes you need to go through the process more than once for the computer to clear its cache, but once you do, you should be good to go.

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