USB Device Class Definition for Audio Data Formats
Release 1.0 March 18, 1998 iv
Table of Contents
Scope of This Release.........................................................................................................ii
Contributors.........................................................................................................................ii
Revision History ..................................................................................................................ii
Table of Contents...............................................................................................................iv
List of Tables.......................................................................................................................v
1 Introduction..................................................................................................................6
1.1 Related Documents .................................................................................................6
1.2 Terms and Abbreviations.........................................................................................6
2 Audio Data Formats......................................................................................................8
2.1 Transfer Delimiter....................................................................................................8
2.2 Type I Formats ........................................................................................................8
2.2.1 USB Packets ....................................................................................................8
2.2.2 Audio Subframe................................................................................................9
2.2.3 Audio Frame.....................................................................................................9
2.2.4 Audio Streams..................................................................................................9
2.2.5 Type I Format Type Descriptor .......................................................................10
2.2.6 Supported Formats .........................................................................................11
2.3 Type II Formats .....................................................................................................12
2.3.1 Encoded Audio Frames...................................................................................12
2.3.2 Audio Bitstreams.............................................................................................12
2.3.3 USB Packets ..................................................................................................13
2.3.4 Bandwidth Allocation.......................................................................................13
2.3.5 Timing ............................................................................................................13
2.3.6 Type II Format Type Descriptor ......................................................................13
2.3.7 Rate feedback ................................................................................................15
2.3.8 Supported Formats .........................................................................................15
2.4 Type III Formats ....................................................................................................26
2.4.1 Type III Format Type Descriptor .....................................................................26
3 Adding New Audio Data Formats ..............................................................................28
Appendix A. Additional Audio Device Class Codes .....................................................29
A.1 Audio Data Format Codes......................................................................................29
A.1.1 Audio Data Format Type I Codes....................................................................29
A.1.2 Audio Data Format Type II Codes...................................................................29
A.1.3 Audio Data Format Type III Codes..................................................................29
A.2 Format Type Codes...............................................................................................30
A.1 Format-Specific Control Selectors .........................................................................30
A.3...................................................................................................................................30
A.3.1 MPEG Control Selectors.................................................................................30
A.3.2 AC-3 Control Selectors ...................................................................................30
