Open host controller interface
Open Host Controller Interface ( OHCI ) is an open standard that allows a computer to communicate with FireWire and USB devices.
With regard to FireWire cards and controller chips, OHCI means that the card / chip supports a PCI -based standard interface that can be used by OHCI Firewire drivers as offered by all modern operating systems. Thanks to the standard interface, the operating system does not need to know any details of the controller, but can address it with a set of well-defined commands.
See also
Universal Host Controller Interface (UHCI) and Enhanced Host Controller Interface (EHCI) , see The Different Host Controllers