Freescale Semiconductor TWR-MCF52259-Ethenet, User Manual, Page: 86 / 166

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Introduction to USB
• Single Host – The host controls communication with each device
• Up to 127 devices can be attached
• Devices are one of the following:
– Hubs (provide additional attachment points)
– Functions (devices) which provide capabilities to the system (e.g.,
printer, thumb drive, I-pod)
• Up to 7 tiers
– Can have up to 5 hubs deep with a max of 5 meters between each
hub
USB Spec Provides for a Flexible Tiered Star Topology
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Topology