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USB

io (2) ehci (1) hci (1) ohci (1) uhci (1) xhci (1) usb (1)
Luka Dorotic

USB

USB devices are controlled through a Host Controller Interface (HCI). There are four types of HCIs for the different versions of USB. USB 1 has the UHCI (by Intel) and OHCI (by Microsoft, Semiconductor and others). USB 2 has the EHCI and USB 3 got the xHCI.

The different HCIs are found on the [PCI] Bus. They share the Class 0x0C and SubClass 0x03, their Interface Values are as follows:

  • UHCI: 0x00
  • OHCI: 0x10
  • EHCI: 0x20
  • xHCI: 0x30

Host Controller Interface (HCI)