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NRZI (Non Return to Zero Invert) encoding scheme used to send data with a sync field to synchronise the host and receiver clocks. It uses 4 shielded wires: two for power (+5v & GND) and two for differential data signals (labelled as D+ and D- in pinout). The additional pin is used as an attached device presence indicator. Mini-USB pinout and Micro-USB pinout are slightly different: standard USB uses 4 pins while Mini-USB and Micro-USB uses 5 pins in connector. Nowdays there are 7 USB connectors known: Standard-A, Standard-B, Mini-A, Mini-B, Micro-A, Micro-AB, Micro-B, Type-C. The original USB specification detailed Standard-A and Standard-B plugs and receptacles. The connector mounted on the host or device is called the receptacle, and the connector attached to the cable is called the plug. There are several types of USB connectors.
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USB interface aimed to remove the need for adding expansion cards into the computer's PCI or PCI-Express bus, and improve plug-and-play capabilities by allowing devices to be hot swapped or added to the system without rebooting the computer. For many of those devices, USB has become the standard connection method. USB can connect computer peripherals such as mice, keyboards, digital cameras, PDA, mobile phones, printers, personal media players, Media Transfer Protocol (MTP) devices, flash drives, GPS, Network Adapters, and external hard drives. Additional USB hubs may be included allowing branching into a tree structure with up to five tier levels.
#OCP USB TO SERIAL CONNECTOR PORTABLE#
Due to the ability to supply power to the preipheral devices USB is often used as a power charger for portable devices.Īn USB system architecture consists of a host controller, a USB ports, and multiple connected devices. Nowdays USB has replaced a variety of earlier PC interfaces (such as RS-232 serial, parallel port, and even FireWire).
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Universal Serial Bus (USB) is an interface to establish communication between devices and a host controller (usually personal computer).
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