Universal Serial Bus 3.0 Specification.pdf

Acknowledgement of USB 3.0 Technical Contribution 1 Introduction 1.1 Motivation.................................................................................................................1-1 1.2 Objective of the Specification...................................................................................1-2 1.3 Scope of the Document............................................................................................1-2 1.4 USB Product Compliance.........................................................................................1-2 1.5 Document Organization............................................................................................1-3 1.6 Design Goals............................................................................................................1-3 1.7 Related Documents..................................................................................................1-3 2 Terms and Abbreviations 3 SuperSpeed USB Architectural Overview 3.1 USB 3.0 Overview....................................................................................................3-1 3.1.1 SuperSpeed Architecture Overview........................................................3-2 3.1.1.1 Physical Layer.................................................................3-2 3.1.1.2 Link Layer........................................................................3-3 3.1.1.3 Protocol Layer.................................................................3-3 3.1.1.4 Hubs................................................................................3-4 3.1.1.5 Power Management........................................................3-5 3.2 USB 3.0 System.......................................................................................................3-5 3.2.1 Comparing SuperSpeed USB to USB 2.0 ..............................................3-5 3.2.2 System Level Topology ..........................................................................3-7 3.2.2.1 Hosts...............................................................................3-7 3.2.2.2 Hubs................................................................................3-8 3.2.2.3 Devices ...........................................................................3-8 3.2.3 Bus Protocol ...........................................................................................3-9 3.2.4 Robustness...........................................................................................3-10 3.2.4.1 Error Detection..............................................................3-10 3.2.4.2 Error Handling...............................................................3-10 3.3 USB Specification Chapter Overview.....................................................................3-11 3.3.1 Mechanical............................................................................................3-12 3.3.2 Physical Layer ......................................................................................3-14 3.3.3 Link Layer .............................................................................................3-15 3.3.4 Protocol Layer.......................................................................................3-15 3.3.5 Framework Layer..................................................................................3-16 3.3.6 Hubs .....................................................................................................3-16 3.3.6.1 Hub Architecture ...........................................................3-17 3.3.6.2 Hub Repeater/Forwarder Architecture ..........................3-18 3.3.6.3 Hubs and Transfers to Power Managed Links ..............3-18 3.3.7 Performance and Power Efficiency.......................................................3-18