Search results
Results from the WOW.Com Content Network
For example, a USB 2 PCIe host controller card that presents 4 USB "Standard A" connectors typically presents one 4-port EHCI and two 2-port OHCI controllers to system software. When a high-speed USB device is attached to any of the 4 connectors, the device is managed through one of the 4 root hub ports of the EHCI controller.
The hub built into the host controller is called the root hub. A USB device may consist of several logical sub-devices that are referred to as device functions . A composite device may provide several functions, for example, a webcam (video device function) with a built-in microphone (audio device function).
A four-port "long cable" "external box" USB hub A four-port "compact design" USB hub: upstream and downstream ports shown. A USB hub is a device that expands a single Universal Serial Bus (USB) port into several so that there are more ports available to connect devices to a host system, similar to a power strip. All devices connected through a ...
Initially, all packets are sent from the host via the root hub, and possibly more hubs, to devices. Some of those packets direct a device to send some packets in reply. After the sync field, all packets are made of 8-bit bytes, transmitted least-significant bit first. The first byte is a packet identifier (PID) byte.
Rooting [1] is the process by which users of Android devices can attain privileged control (known as root access) over various subsystems of the device, usually smartphones and tablets. Because Android is based on a modified version of the Linux kernel , rooting an Android device gives similar access to administrative ( superuser ) permissions ...
USB device controller, supporting both high and full speeds; Fourth controller to switch the OTG root port between host and device controllers; Also, most gadgets must be either a host or a device. OTG hardware design merges all of the controllers into one dual-role controller that is somewhat more complex than an individual device controller.
Open Host Controller Interface (OHCI) [1] is an open standard.. Die shot of a VIA VT6307 Integrated Host Controller used for IEEE 1394A communication. When applied to an IEEE 1394 (also known as FireWire; i.LINK or Lynx) card, OHCI means that the card supports a standard interface to the PC and can be used by the OHCI IEEE 1394 drivers that come with all modern operating systems.
USB 3.0 SuperSpeed – host controller (xHCI) hardware support, no software overhead for out-of-order commands; USB 2.0 High-speed – enables command queuing in USB 2.0 drives; Streams were added to the USB 3.0 SuperSpeed protocol for supporting UAS out-of-order completions USB 3.0 host controller (xHCI) provides hardware support for streams