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USB (Universal Serial Bus)

USB is a device that can be attached, configured and used, reset, reconfigured and used, share the bandwidth with other devices, detached (while others are in operation) and reattached
  • Developed by Intel, Microsoft and Philips in 1998.Initial model was USB 1.0.
  • The latest version is USB 2.0.
  • Currently supported versions are USB 1.1 and 2.0
  • The Speed of USB 1.1 is(1.5Mbps or 12 Mbps)
  • The speed of USB 2.0 is 480Mbps.
  • USBs are bus powered or self powered.
  • USBs are hot pluggable (once they are installed, there is no need for rebooting the system).
  • USBs share their bandwidth.
  • 127 USB devices can be connected to a single USB slot and all the devices shares the bandwidth.
  • USBs has four wires, one for +5v, one for ground and two for twisted pair cables.
  • The next version under research is USB3.0, the speed of it may be around 4.8Gbps.

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