USB Device Class Definition for Audio Devices
Release 2.0
May 31, 2006 6
Table of Contents
Scope of This Release.............................................................................................................2
Contributors............................................................................................................................2
Revision History.......................................................................................................................2
Table of Contents.....................................................................................................................6
List of Tables...........................................................................................................................9
List of Figures........................................................................................................................12
1 Introduction....................................................................................................................13
1.1 Scope.........................................................................................................................13
1.2 Purpose.....................................................................................................................13
1.3 Related Documents...................................................................................................13
1.4 Terms and Abbreviations...........................................................................................13
2 Management Overview...................................................................................................16
2.1 Overview of Key Differences between ADC v1.0 and v2.0.......................................16
3 Functional Characteristics.............................................................................................18
3.1 Introduction................................................................................................................18
3.2 Audio Interface Collection (AIC)................................................................................19
3.3 Audio Function Class.................................................................................................19
3.4 Audio Function Subclass...........................................................................................19
3.5 Audio Function Protocol............................................................................................19
3.6 Audio Interface Class................................................................................................20
3.7 Audio Interface Subclass...........................................................................................20
3.8 Audio Interface Protocol............................................................................................20
3.9 Audio Function Category...........................................................................................20
3.10 Clock Domains.......................................................................................................21
3.11 Audio Synchronization Types................................................................................21
3.11.1 Asynchronous.................................................................................................21
3.11.2 Synchronous...................................................................................................21
3.11.3 Adaptive..........................................................................................................21
3.12 Inter Channel Synchronization...............................................................................21
3.13 Audio Function Topology.......................................................................................22
3.13.1 Audio Channel Cluster....................................................................................25
3.13.2 Input Terminal.................................................................................................27
3.13.3 Output Terminal..............................................................................................28
3.13.4 Mixer Unit........................................................................................................29
3.13.5 Selector Unit...................................................................................................29
3.13.6 Feature Unit....................................................................................................30
3.13.7 Sampling Rate Converter Unit........................................................................30
3.13.8 Effect Unit.......................................................................................................31
3.13.9 Processing Unit...............................................................................................34
3.13.10 Extension Unit.................................................................................................35
USB Device Class Definition for Audio Devices
Release 2.0
May 31, 2006 7
3.13.11 Clock Entities..................................................................................................36
3.14 Encoders and Decoders........................................................................................37
3.15 Copy Protection.....................................................................................................38
3.16 Operational Model..................................................................................................38
3.16.1 AudioControl Interface....................................................................................39
3.16.2 AudioStreaming Interface...............................................................................39
3.16.3 Clock Model....................................................................................................41
3.16.4 Binding between Physical Buttons and Audio Controls.................................41
4 Descriptors.....................................................................................................................43
4.1 Audio Channel Cluster Descriptor.............................................................................43
4.2 Device Descriptor......................................................................................................45
4.3 Device_Qualifier Descriptor.......................................................................................45
4.4 Configuration Descriptor............................................................................................46
4.5 Other_Speed_Configuration Descriptor....................................................................46
4.6 Interface Association Descriptor................................................................................46
4.7 AudioControl Interface Descriptors...........................................................................47
4.7.1 Standard AC Interface Descriptor......................................................................47
4.7.2 Class-Specific AC Interface Descriptor..............................................................48
4.8 AudioControl Endpoint Descriptors...........................................................................73
4.8.1 AC Control Endpoint Descriptors.......................................................................74
4.8.2 AC Interrupt Endpoint Descriptors.....................................................................74
4.9 AudioStreaming Interface Descriptors.......................................................................75
4.9.1 Standard AS Interface Descriptor......................................................................75
4.9.2 Class-Specific AS Interface Descriptor..............................................................75
4.9.3 Class-Specific AS Format Type Descriptor........................................................77
4.9.4 Class-Specific AS Encoder Descriptor...............................................................77
4.9.5 Class-Specific AS Decoder Descriptor..............................................................78
4.10 AudioStreaming Endpoint Descriptors...................................................................85
4.10.1 AS Isochronous Audio Data Endpoint Descriptors.........................................85
4.10.2 AS Isochronous Feedback Endpoint Descriptor.............................................87
5 Requests.........................................................................................................................89
5.1 Standard Requests....................................................................................................89
5.2 Class-Specific Requests............................................................................................89
5.2.1 Control Attributes................................................................................................89
5.2.2 Control Request Layout......................................................................................90
5.2.3 Control Request Parameter Block Layout..........................................................91
5.2.4 Common Controls..............................................................................................94
5.2.5 AudioControl Requests......................................................................................97
5.2.6 AudioStreaming Requests...............................................................................116
5.2.7 Additional Requests.........................................................................................127
6 Interrupts......................................................................................................................129
6.1 Interrupt Data Message...........................................................................................129
6.2 Interrupt Sources.....................................................................................................130
USB Device Class Definition for Audio Devices
Release 2.0
May 31, 2006 8
Appendix A. Audio Device Class Codes.....................................................................131
A.1 Audio Function Class Code.....................................................................................131
A.2 Audio Function Subclass Codes.............................................................................131
A.3 Audio Function Protocol Codes...............................................................................131
A.4 Audio Interface Class Code.....................................................................................131
A.5 Audio Interface Subclass Codes.............................................................................131
A.6 Audio Interface Protocol Codes...............................................................................132
A.7 Audio Function Category Codes.............................................................................132
A.8 Audio Class-Specific Descriptor Types...................................................................132
A.9 Audio Class-Specific AC Interface Descriptor Subtypes.........................................133
A.10 Audio Class-Specific AS Interface Descriptor Subtypes.....................................133
A.11 Effect Unit Effect Types.......................................................................................134
A.12 Processing Unit Process Types...........................................................................134
A.13 Audio Class-Specific Endpoint Descriptor Subtypes...........................................134
A.14 Audio Class-Specific Request Codes..................................................................134
A.15 Encoder Type Codes...........................................................................................135
A.16 Decoder Type Codes...........................................................................................135
A.17 Control Selector Codes........................................................................................135
A.17.1 Clock Source Control Selectors....................................................................135
A.17.2 Clock Selector Control Selectors..................................................................136
A.17.3 Clock Multiplier Control Selectors.................................................................136
A.17.4 Terminal Control Selectors...........................................................................136
A.17.5 Mixer Control Selectors................................................................................136
A.17.6 Selector Control Selectors............................................................................137
A.17.7 Feature Unit Control Selectors.....................................................................137
A.17.8 Effect Unit Control Selectors........................................................................138
A.17.9 Processing Unit Control Selectors................................................................140
A.17.10 Extension Unit Control Selectors..................................................................141
A.17.11 AudioStreaming Interface Control Selectors................................................141
A.17.12 Encoder Control Selectors............................................................................142
A.17.13 Decoder Control Selectors...........................................................................142
A.17.14 Endpoint Control Selectors...........................................................................144
USB Device Class Definition for Audio Devices
Release 2.0
May 31, 2006 9
List of Tables
Table 4-1: Audio Channel Cluster Descriptor.....................................................................44
Table 4-1: Dolby Prologic Cluster Descriptor.....................................................................44
Table 4-2: Left Group Cluster Descriptor............................................................................44
Table 4-3: Standard Interface Association Descriptor.......................................................46
Table 4-4: Standard AC Interface Descriptor......................................................................47
Table 4-5: Class-Specific AC Interface Header Descriptor................................................48
Table 4-6: Clock Source Descriptor.....................................................................................49
Table 4-7: Clock Selector Descriptor...................................................................................50
Table 4-8: Clock Multiplier Descriptor.................................................................................51
Table 4-9: Input Terminal Descriptor...................................................................................53
Table 4-10: Output Terminal Descriptor..............................................................................54
Table 4-11: Mixer Unit Descriptor.........................................................................................57
Table 4-12: Selector Unit Descriptor....................................................................................58
Table 4-13: Feature Unit Descriptor.....................................................................................59
Table 4-14: Sampling Rate Converter Unit Descriptor.......................................................60
Table 4-15: Common Part of the Effect Unit Descriptor....................................................61
Table 4-16: Parametric Equalizer Section Effect Unit Descriptor.....................................62
Table 4-17: Reverberation Effect Unit Descriptor...............................................................63
Table 4-18: Modulation Delay Effect Unit Descriptor.........................................................63
Table 4-19: Dynamic Range Compressor Effect Unit Descriptor......................................64
Table 4-20: Common Part of the Processing Unit Descriptor...........................................66
Table 4-21: Up/Down-mix Processing Unit Descriptor......................................................68
Table 4-22: Dolby Prologic Processing Unit Descriptor....................................................69
Table 4-23: Stereo Extender Processing Unit Descriptor..................................................71
Table 4-24: Extension Unit Descriptor.................................................................................73
Table 4-25: Standard AC Interrupt Endpoint Descriptor....................................................74
Table 4-26: Standard AS Interface Descriptor....................................................................75
Table 4-27: Class-Specific AS Interface Descriptor...........................................................76
Table 4-28: Encoder Descriptor............................................................................................77
Table 4-29: MPEG Decoder Descriptor................................................................................79
Table 4-30: AC-3 Decoder Descriptor..................................................................................81
Table 4-31: WMA Decoder Descriptor..................................................................................83
Table 4-32: DTS Decoder Descriptor...................................................................................84
Table 4-33: Standard AS Isochronous Audio Data Endpoint Descriptor.........................85
Table 4-34: Class-Specific AS Isochronous Audio Data Endpoint Descriptor................87
USB Device Class Definition for Audio Devices
Release 2.0
May 31, 2006 10
Table 4-35: Standard AS Isochronous Feedback Endpoint Descriptor...........................87
Table 5-1: Request Layout....................................................................................................90
Table 5-2: 1-byte Control CUR Parameter Block................................................................92
Table 5-3: 1-byte Control RANGE Parameter Block...........................................................92
Table 5-4: 2-byte Control CUR Parameter Block................................................................93
Table 5-5: 2-byte Control RANGE Parameter Block...........................................................93
Table 5-6: 4-byte Control CUR Parameter Block................................................................93
Table 5-7: 4-byte Control RANGE Parameter Block...........................................................94
Table 5-8: Cluster Control CUR Parameter Block..............................................................95
Table 5-9: Error Codes..........................................................................................................96
Table 5-10: Connector Control CUR Parameter Block.....................................................100
Table 5-11: Band Numbers and Center Frequencies (ANSI S1.11-1986 Standard).......104
Table 5-12: Graphic Equalizer Control CUR Parameter Block........................................105
Table 5-13: Graphic Equalizer Control RANGE Parameter Block...................................105
Table 5-14: Valid Alternate Settings Control CUR Parameter Block..............................117
Table 5-15: High/Low Scaling Control CUR Parameter Block.........................................122
Table 5-16: High/Low Scaling Control RANGE Parameter Block...................................122
Table 5-17: High/Low Scaling Control CUR Parameter Block.........................................125
Table 5-18: High/Low Scaling Control RANGE Parameter Block...................................125
Table 5-19: Memory Request Values..................................................................................128
Table 6-1: Interrupt Data Message Format........................................................................130
Table A-1: Audio Function Class Code.............................................................................131
Table A-2: Audio Function Subclass Codes.....................................................................131
Table A-3: Audio Function Protocol Codes......................................................................131
Table A-4: Audio Interface Class Code..............................................................................131
Table A-5: Audio Interface Subclass Codes.....................................................................131
Table A-6: Audio Interface Protocol Codes.......................................................................132
Table A-7: Audio Function Category Codes.....................................................................132
Table A-8: Audio Class-specific Descriptor Types...........................................................132
Table A-9: Audio Class-Specific AC Interface Descriptor Subtypes..............................133
Table A-10: Audio Class-Specific AS Interface Descriptor Subtypes............................133
Table A-11: Effect Unit Effect Types..................................................................................134
Table A-12: Processing Unit Process Types.....................................................................134
Table A-13: Audio Class-Specific Endpoint Descriptor Subtypes..................................134
Table A-14: Audio Class-Specific Request Codes...........................................................134
Table A-15: Encoder Type Codes.......................................................................................135
最終更新：2011年05月08日 13:35
