A virtual machine must have a USB controller to use USB devices and smart card readers. To use a smart card reader, a virtual machine must have a USB controller regardless of whether the smart card reader is actually a USB device.

Workstation provides a USB controller to support the following types of USB devices.

USB 1.1 UHCI (Universal Host Controller Interface) is supported for all virtual machine hardware versions.

USB 2.0 EHCI (Enhanced Host Controller Interface) controllers are supported if the virtual machine hardware is compatible with Workstation 6 and later virtual machines.

USB 3.0 xHCI (Extensible Host Controller Interface) support is available for Linux guests running kernel version 2.6.35 or later and for Windows 8 guests. The virtual machine hardware must be compatible with Workstation 8 or later virtual machines.

For USB 2.0 or 3.0 support, you must select USB 2.0 or 3.0 compatibility by configuring virtual machine settings for the USB controller. USB 2.0 and 3.0 devices are high-speed devices that include the latest models of USB flash drives, USB hard drives, iPods, and iPhone.

If you select USB 2.0 compatibility, when a USB 2.0 device connects to a USB port on the host system, the device connects to the EHCI controller and operates in USB 2.0 mode. A USB 1.1 device connects to the UHCI controller and operates in USB 1.1 mode. If you enable USB 3.0, the xHCI controller can support all USB devices, including USB 1.1, 2.0, and 3.0 devices.

Although the host operating system must support USB, you do not need to install device-specific drivers for USB devices in the host operating system to use those devices only in the virtual machine. Windows NT and Linux kernels earlier than 2.2.17 do not support USB.

VMware has tested a variety of USB devices. If the guest operating system has the appropriate drivers, you can use many different USB devices, including PDAs, Smart phones, printers, storage devices, scanners, MP3 players, digital cameras, memory card readers, and isochronous transfer devices, such as webcams, speakers, and microphones.

You can connect USB human interface devices (HIDs), such as the keyboard and mouse, to a virtual machine by enabling the Show all USB input devices option. If you do not select this option, these devices do not appear in the Removable Devices menu and are not available to connect to the virtual machine, even though they are plugged in to USB ports on the host system.

See Connect USB HIDs to a Virtual Machine for information on connecting HIDs.