Extensible Host Controller Interface: Difference between revisions

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{{Redirect|XHCI|the radio station|XHCI-FM}}openai chboi{{short description|Computer interface specification}}

{{short description|Computer interface specification}}

{{More footnotes|date=April 2014}}

'''The eXtensible Host Controller Interface''' ('''xHCI''') is a computer interfacetechnical specification that definesprovides a register-leveldetailed framework for the descriptionfunctioning of a [[computer's host controller]] for [[Universal Serial Bus]] (USB),. whichKnown isalternately capableas of interfacing withthe USB 1.x, 23.0 host controller specification, andxHCI 3.xis designed to be backward compatible, devices.supporting Thea specificationwide isrange alsoof referredUSB todevices asfrom theolder [[USB 31.0]]x hostto controllerthe specificationmore recent USB 3.x versions.

xHCIDistinct improvesfrom onits predecessors, the pre-existing [[Open Host Controller Interface]] (OHCI) and the [[Universal Host Controller Interface]] (UHCI), architecturesxHCI mostoffers prominentlyseveral intechnological handlingimprovements. aSpecifically, widerit rangeis ofdesigned to handle multiple data transfer speeds (low, full, high, and SuperSpeed) within a single unified standard,. This makes it more efficient in managing resourcescomputational moreand efficientlypower forresources, thea benefitfeature ofparticularly beneficial for mobile hostsdevices with limited power resources (suchcapabilities aslike tablets and cellsmartphones. phones)Additionally, andxHCI insimplifies simplifyingthe architecture needed to support fora mixingmixture of low-speed and high-speed devices., which streamlines the development of drivers and system software.

xHCI marks a significant improvement over its predecessors, the Open Host Controller Interface (OHCI) and the Universal Host Controller Interface (UHCI), in several key ways:

# '''Multi-Speed Support''': Unlike OHCI and UHCI, which were limited to specific USB speeds, xHCI is capable of managing multiple data transfer speeds—low, full, high, and SuperSpeed—under a single standard. This eliminates the need for multiple host controllers or complex switching mechanisms when dealing with various types of USB devices, thereby improving efficiency.

# '''Power Management''': xHCI includes advanced power management features that allow for selective suspension of USB devices and more granular power distribution. This is especially beneficial for mobile devices with limited battery life, such as tablets and smartphones, as it helps to maximize power utilization and extend battery life.

# '''Streamlined Architecture''': xHCI's architecture is designed to be simpler and more straightforward, reducing the complexity of driver development. In older architectures like OHCI and UHCI, supporting a mix of low-speed and high-speed devices required complicated algorithms and multiple transaction translators. xHCI simplifies this by integrating these functions into the host controller itself, thus easing the burden on system software and driver developers.

By enhancing support for multiple speeds, optimizing power management, and simplifying the underlying architecture, xHCI serves as a more efficient and unified standard for USB host controllers.

== Architectural goals ==