USB Complete 3rdEdition下载

1. USB Basics 1 What USB Can Do 2 Benefits for Users 2 Benefits for Developers 6 Beyond the Hype 10 Evolution of an Interface 13 Original USB 14 USB 2.0 15 USB On-The-Go 16 Wireless USB 16 USB versus IEEE-1394 16 USB versus Ethernet 17 Bus Components 17 Topology 18 Defining Terms 19 Contents iv Division of Labor 22 The Host’s Duties 22 The Peripheral’s Duties 25 What about Speed? 28 Developing a Device 29 Elements in the Link 29 Tools for Developing 30 Steps in Developing a Project 30 2. Inside USB Transfers 33 Transfer Basics 34 Enumeration Communications 34 Application Communications 34 Managing Data on the Bus 35 Host Speed and Bus Speed 36 Elements of a Transfer 37 Device Endpoints: the Source and Sink of Data 38 Pipes: Connecting Endpoints to the Host 40 Types of Transfers 40 Stream and Message Pipes 42 Initiating a Transfer 43 Transactions: the Building Blocks of a Transfer 44 Transaction Phases 45 Ensuring that Transfers Are Successful 51 Handshaking 51 Reporting the Status of Control Transfers 55 Error Checking 56 3. A Transfer Type for Every Purpose 61 Control Transfers 61 Availability 62 Structure 62 Data Size 66 Speed 66 Detecting and Handling Errors 68 Bulk Transfers 68 Availability 69 Structure 69 Data Size 69 Speed 71 Detecting and Handling Errors 71 Contents v Interrupt Transfers 72 Availability 72 Structure 72 Data Size 73 Speed 73 Detecting and Handling Errors 75 Isochronous Transfers 76 Availability 76 Structure 76 Data Size 79 Speed 79 Detecting and Handling Errors 80 More about Time-critical Transfers 80 Bus Bandwidth 81 Device Capabilities 81 Host Capabilities 82 Host Latencies 83 4. Enumeration: How the Host Learns about Devices 85 The Process 86 Enumeration Steps 87 Enumerating a Hub 91 Device Removal 92 Tips for Successful Enumeration 92 Descriptors 93 Types of Descriptors 94 Device Descriptor 96 Device_qualifier Descriptor 99 Configuration Descriptor 101 Other_speed_configuration Descriptor 103 Interface Association Descriptor 103 Interface Descriptor 106 Endpoint Descriptor 108 String Descriptor 112 Other Standard Descriptors 113 The Microsoft OS Descriptor 114 Descriptors in 2.0-compliant Devices 114 Making 1.x Descriptors 2.0-compliant 114 Detecting the Speed of a Dual-Speed Device 116 Contents vi 5. Control Transfers: Structured Requests for Critical Data 117 Elements of a Control Transfer 117 Setup Stage 118 Data Stage 120 Status Stage 122 Handling Errors 124 Device Firmware 125 The Requests 127 Get_Status 129 Clear_Feature 130 Set_Feature 131 Set_Address 132 Get_Descriptor 133 Set_Descriptor 134 Get_Configuration 135 Set_Configuration 136 Get_Interface 137 Set_Interface 138 Synch_Frame 139 Other Control Requests 140 Class-specific Requests 140 Vendor-specific Requests 140 6. Chip Choices 141 Components of a USB Device 142 The USB Controller 143 Other Device Components 145 Simplifying Device Development 148 Device Requirements 149 Chip Documentation 150 Driver Choices 151 Debugging Tools 151 Controllers with Embedded CPUs 154 Microchip PIC18F4550 156 Cypress EZ-USB 157 Cypress enCoRe II 163 Freescale MC68HC908JB16 164 Freescale MCF5482 ColdFire 164 Contents vii Controllers that Interface to External CPUs 165 National Semiconductor USBN9603 165 Philips Semiconductors ISP1181B 167 Philips Semiconductors ISP1581 168 PLX Technology NET2272 169 FTDI Chip FT232BM and FT245BM 170 7. Device Classes 177 About Classes 177 Device Working Groups 178 Elements of a Class Specification 178 Defined Classes 181 Audio 181 Chip/Smart Card Interface 189 Communication Devices: Modems and Networks 191 Content Security 198 Device Firmware Upgrade 200 Human Interface 203 IrDA Bridge 206 Mass Storage 208 Printers 213 Still Image Capture: Cameras and Scanners 217 Test and Measurement 220 Video 221 Implementing Non-standard Functions 226 Standard or Custom Driver? 226 Converting from RS-232 227 Converting from the Parallel Port 229 PC-to-PC Communications 229 Using a Generic Driver 231 8. How the Host Communicates 233 Device Driver Basics 233 Insulating Applications from the Details 234 Options for USB Devices 235 User and Kernel Modes 235 WDM Drivers 237 Layered Drivers 238 Communication Flow 243 More Examples 246 Contents viii Creating a Custom Driver 247 Writing a Driver from Scratch 247 Using a Driver Toolkit 248 Using GUIDs 249 Device Setup GUIDs 250 Device Interface GUIDs 251 9. Matching a Driver to a Device 253 Using the Device Manager 253 Viewing Devices 254 Property Pages 257 Device Information in the Registry 257 The Hardware Key 258 The Class Key 259 The Driver Key 260 The Service Key 262 Inside INF Files 262 Syntax 265 Sections 266 Using Device Identification Strings 272 Finding a Match 274 Do You Need to Provide an INF File? 276 Tools and Diagnostic Aids 277 Tips for Using INF Files 277 What the User Sees 279 10. Detecting Devices 281 A Brief Guide to Calling API Functions 281 Managed and Unmanaged Code 282 Documentation 284 Using Visual C++ .NET 284 Using Visual Basic .NET 286 Finding Your Device 291 Obtaining the Device Interface GUID 292 Requesting a Pointer to a Device Information Set 293 Identifying a Device Interface 295 Requesting a Structure Containing the Device Path Name 298 Extracting the Device Path Name 301 Closing Communications 302 Contents ix Obtaining a Handle 303 Requesting a Communications Handle 303 Closing the Handle 306 Detecting Attachment and Removal 306 About Device Notifications 307 Registering for Device Notifications 307 Capturing Device Change Messages 311 Reading Device Change Messages 312 Retrieving the Device Path Name in the Message 314 Stopping Device Notifications 317 11. Human Interface Devices: Using Control and Interrupt Transfers 319 What is a HID? 320 Hardware Requirements 321 Firmware Requirements 323 Identifying a Device as a HID 323 The HID Interface 326 HID Class Descriptor 326 Report Descriptors 328 HID-specific Requests 330 Get_Report 332 Get_Idle 333 Get_Protocol 334 Set_Report 335 Set_Idle 336 Set_Protocol 337 Transferring Data 338 About the Example Code 338 Sending Reports via Interrupt Transfers 340 Receiving Reports via Interrupt Transfers 343 Sending Reports via Control Transfers 345 Receiving Reports via Control Transfers 347 12. Human Interface Devices: Reports 351 Report Structure 351 Using the HID Descriptor Tool 352 Control and Data Item Values 354 Item Types 354 Contents x The Main Item Type 355 Input, Output, and Feature Items 356 Collection and End Collection Items 360 The Global Item Type 361 Identifying the Report 361 Describing the Data’s Use 363 Converting Units 365 Converting Raw Data 366 Describing the Data’s Size and Format 369 Saving and Restoring Global Items 369 The Local Item Type 370 Physical Descriptors 373 Padding 373 13. Human Interface Devices: Host Application 375 HID API Functions 375 Requesting Information about the HID 376 Sending and Receiving Reports 376 Providing and Using Report Data 378 Managing HID Communications 379 Identifying a Device 379 Reading the Vendor and Product IDs 380 Getting a Pointer to a Buffer with Device Capabilities 384 Getting the Device’s Capabilities 385 Getting the Capabilities of the Buttons and Values 388 Sending and Receiving Reports 388 Sending an Output Report to the Device 389 Reading an Input Report from the Device 392 Writing a Feature Report to the Device 402 Reading a Feature Report from a Device 404 Closing Communications 406 14. Bulk Transfers for Any CPU 407 Two Projects 407 Asynchronous Serial Interface 408 Parallel Interface 414 Host Programming 421 Using the D2XX Direct Driver 422 Selecting a Driver 422 Contents xi Performance Tips 426 Speed Considerations 426 Minimizing Latency 427 Preventing Lost Data 428 EEPROM Programming 429 EEPROM Data 429 Editing the Data 429 15. Hubs: the Link between Devices and the Host 433 Hub Basics 434 The Hub Repeater 435 The Transaction Translator 438 The Hub Controller 444 Speed 445 Maintaing an Idle Bus 447 How Many Hubs in Series? 447 The Hub Class 448 Hub Descriptors 448 Hub-class Requests 452 Port Indicators 453 16. Managing Power 455 Powering Options 455 Voltages 456 Which Peripherals Can Use Bus Power? 457 Power Needs 458 Informing the Host 459 Hub Power 461 Power Sources 461 Over-current Protection 462 Power Switching 463 Saving Power 464 Global and Selective Suspends 464 Current Limits for Suspended Devices 464 Resuming Communications 466 Power Management under Windows 467 17. Testing and Debugging 471 Tools 471 Hardware Protocol Analyzers 472 Software Protocol Analyzers 475 Traffic Generators 477 Contents xii Testing 477 Compliance Testing 478 WHQL Testing 484 18. Signals and Encoding 489 Bus States 489 Low-speed and Full-speed Bus States 490 High-speed Bus States 492 Data Encoding 494 Staying Synchronized 496 Timing Accuracy 498 Packet Format 499 Fields 499 Inter-packet Delay 501 Test Modes 502 Entering and Exiting Test Modes 502 The Modes 502 19. The Electrical Interface 505 Transceivers and Signals 506 Cable Segments 506 Low- and Full-speed Transceivers 508 High-speed Transceivers 512 Signal Voltages 517 Low and Full Speeds 517 High Speed 518 Cables 518 Conductors 518 Connectors 520 Detachable and Captive Cables 524 Cable Length 524 Ensuring Signal Quality 525 Sources of Noise 526 Balanced Lines 527 Twisted Pairs 527 Shielding 528 Edge Rates 529 Isolated Interfaces 529 Contents xiii Wireless Links 530 Cypress WirelessUSB 530 The Wireless USB Initiative 533 Other Options 534 20. Dual-role Devices with USB On-The-Go 535 Device and Host in One 536 Capabilities and Limits 536 Requirements for an OTG Device 538 The OTG Descriptor 545 Feature Codes for HNP 545 OTG Controller Chips 545 Philips ISP1362 546 TransDimension TD242LP 547 Cypress CY7C67200 EZ-OTG 548 Philips ISP1261 Bridge Controller 549