SIST EN IEC 62680-1-7:2020
(Main)Universal serial bus interfaces for data and power - Part 1-7: Common components - USB Audio 3.0 device class definition data formats (IEC 62680-1-7:2019)
Universal serial bus interfaces for data and power - Part 1-7: Common components - USB Audio 3.0 device class definition data formats (IEC 62680-1-7:2019)
The intention of this document is to describe in detail all the Audio Data Formats that are supported by the
Audio Device Class. This document is considered an integral part of the Audio Device Class Specification,
although subsequent revisions of this document are independent of the revision evolution of the main USB
Audio Specification. This is to easily accommodate the addition of new Audio Data Formats without impeding
the core USB Audio Specification.
Schnittstellen des Universellen Seriellen Busses für Daten und Energie - Teil 1-7: Gemeinsame Komponenten - USB Audio 3.0 Geräteklassendefinition Datenformate (IEC 62680-1-7:2019)
Interfaces de bus universel en série pour les données et l'alimentation électrique - Partie 1-7: Composants communs - Définition de classes de dispositifs USB Audio 3.0 pour formats de données (IEC 62680-1-7:2019)
L'IEC 62680-1-7:2019 décrit en détail tous les formats de données audio pris en charge par la classe des dispositifs audio. Le présent document est vu comme faisant partie intégrante de la Spécification de classe de dispositifs audio, bien que les révisions ultérieures du présent document soient indépendantes de l'évolution des révisions de la Spécification USB audio principale. L'objectif est de faciliter la prise en compte de l'ajout de nouveaux formats de données audio sans affecter la Spécification USB audio de base.
Vmesniki univerzalnega serijskega vodila za prenos podatkov in napajanje - 1-7. del: Skupne komponente - Definicija tipa naprave USB Avdio 3.0 za podatkovne formate (IEC 62680-1-7:2019)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN IEC 62680-1-7:2020
01-julij-2020
Vmesniki univerzalnega serijskega vodila za prenos podatkov in napajanje - 1-7.
del: Skupne komponente - Definicija tipa naprave USB Avdio 3.0 za podatkovne
formate (IEC 62680-1-7:2019)
Universal serial bus interfaces for data and power - Part 1-7: Common components -
USB Audio 3.0 device class definition data formats (IEC 62680-1-7:2019)
Schnittstellen des Universellen Seriellen Busses für Daten und Energie - Teil 1-7:
Gemeinsame Komponenten - USB Audio 3.0 Geräteklassendefinition Datenformate
(IEC 62680-1-7:2019)
Interfaces de bus universel en série pour les données et l'alimentation électrique - Partie
1-7: Composants communs - Définition de classes de dispositifs USB Audio 3.0 pour
formats de données (IEC 62680-1-7:2019)
Ta slovenski standard je istoveten z: EN IEC 62680-1-7:2019
ICS:
35.200 Vmesniška in povezovalna Interface and interconnection
oprema equipment
SIST EN IEC 62680-1-7:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN IEC 62680-1-7:2020
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SIST EN IEC 62680-1-7:2020
EUROPEAN STANDARD EN IEC 62680-1-7
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2019
ICS 33.160; 35.100.20
English Version
Universal serial bus interfaces for data and power - Part 1-7:
Common components - USB Audio 3.0 device class definition
data formats
(IEC 62680-1-7:2019)
Interfaces de bus universel en série pour les données et Schnittstellen des Universellen Seriellen Busses für Daten
l'alimentation électrique - Partie 1-7: Composants communs und Energie - Teil 1-7: Gemeinsame Komponenten - USB
- Définition de classes de dispositifs USB Audio 3.0 pour Audio 3.0 Geräteklassendefinition Datenformate
formats de données (IEC 62680-1-7:2019)
(IEC 62680-1-7:2019)
This European Standard was approved by CENELEC on 2019-10-24. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62680-1-7:2019 E
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SIST EN IEC 62680-1-7:2020
EN IEC 62680-1-7:2019 (E)
European foreword
The text of document 100/3159/CDV, future edition 1 of IEC 62680-1-7, prepared by IEC/TC 100
"Audio, video and multimedia systems and equipment" was submitted to the IEC-CENELEC parallel
vote and approved by CENELEC as EN IEC 62680-1-7:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2020-07-24
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-10-24
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Endorsement notice
The text of the International Standard IEC 62680-1-7:2019 was approved by CENELEC as a
European Standard without any modification.
2
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SIST EN IEC 62680-1-7:2020
IEC 62680-1-7
®
Edition 1.0 2019-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Universal serial bus interfaces for data and power –
Part 1-7: Common components – USB Audio 3.0 device class definition data
formats
Interfaces de bus universel en série pour les données et l'alimentation
électrique –
Partie 1-7: Composants communs – Définition de classes de dispositifs USB
Audio 3.0 pour formats de données
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.160; 35.100.20 ISBN 978-2-8322-7243-5
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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SIST EN IEC 62680-1-7:2020
– 2 – IEC 62680-1-7–: 2012 – 9
© USB-IF:1997-2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
UNIVERSAL SERIAL BUS INTERFACES FOR DATA AND POWER –
Part 1-7: Common components –
USB Audio 3.0 device class definition data formats
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
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services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62680-1-7 has been prepared by technical area 18: Multimedia
home systems and applications for end-user networks, of IEC technical committee 100: Audio,
video and multimedia systems and equipment.
The text of this standard was prepared by the USB Implementers Forum (USB-IF). The
structure and editorial rules used in this publication reflect the practice of the organization
which submitted it.
The text of this International Standard is based on the following documents:
CDV Report on voting
100/3159/CDV 100/3229/RVC
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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SIST EN IEC 62680-1-7:2020
IEC– 63 268– 0-1-7:2019 – 3 –
© USB-IF:1997-2016
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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© USB-IF:1997-2016
INTRODUCTION
The IEC 62680 series is based on a series of specifications that were originally developed by the USB
Implementers Forum (USB-IF). These specifications were submitted to the IEC under the auspices of
a special agreement between the IEC and the USB-IF.
This standard is the USB-IF publication USB Device Class Definition for Audio Data Formats Release
3.0.
The USB Implementers Forum, Inc.(USB-IF) is a non-profit corporation founded by the group of
companies that developed the Universal Serial Bus specification. The USB-IF was formed to provide a
support organization and forum for the advancement and adoption of Universal Serial Bus technology.
The Forum facilitates the development of high-quality compatible USB peripherals (devices), and
promotes the benefits of USB and the quality of products that have passed compliance testing.
ANY USB SPECIFICATIONS ARE PROVIDED TO YOU "AS IS, "WITH NO WARRANTIES
WHATSOEVER, INCLUDING ANY WARRANTY OF MERCHANTABILITY, NON-INFRINGEMENT,
OR FITNESS FOR ANY PARTICULAR PURPOSE. THE USB IMPLEMENTERS FORUM AND THE
AUTHORS OF ANY USB SPECIFICATIONS DISCLAIM ALL LIABILITY, INCLUDING LIABILITY
FOR INFRINGEMENT OF ANY PROPRIETARY RIGHTS, RELATING TO USE OR
IMPLEMENTATION OR INFORMATION IN THIS SPECIFICAITON.
THE PROVISION OF ANY USB SPECIFICATIONS TO YOU DOES NOT PROVIDE YOU WITH ANY
LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL
PROPERTY RIGHTS.
Entering into USB Adopters Agreements may, however, allow a signing company to participate in a
reciprocal, RAND-Z licensing arrangement for compliant products. For more information, please see:
https://www.usb.org/documents
IEC DOES NOT TAKE ANY POSITION AS TO WHETHER IT IS ADVISABLE FOR YOU TO ENTER
INTO ANY USB ADOPTERS AGREEMENTS OR TO PARTICIPATE IN THE USB IMPLEMENTERS
FORUM.”
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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SIST EN IEC 62680-1-7:2020
IEC– 65 268– 0-1-7:2019 – 5 –
© USB-IF:1997-2016
UNIVERSAL SERIAL BUS
DEVICE CLASS DEFINITION
FOR
AUDIO DATA FORMATS
Release 3.0
September 22, 2016
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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SIST EN IEC 62680-1-7:2020
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© USB-IF:1997-2016
SCOPE OF THIS RELEASE
This document is the Release 3.0 of this device class definition.
CONTRIBUTORS
Joe Scanlon Advanced Micro Devices
Rhoads Hollowell Apple Inc.
Girault Jones Apple Inc.
Matthew X. Mora Apple Inc.
Tzung-Dar Tsai C-Media Electronics, Inc.
Brad Lambert Cirrus Logic, Inc.
Dan Bogard Conexant Systems, Inc.
Pete Burgers DisplayLink (UK), Ltd.
David Roh Dolby Laboratories, Inc.
Leng Ooi Google, Inc.
Pierre-Louis Bossart Intel Corporation
David Hines Intel Corporation
Abdul Rahman Ismail (Co-Chair) Intel Corporation
Devon Worrell Intel Corporation
Chandrashekhar Rao Logitech, Inc.
Terry Moore MCCI Corporation
Alex Lin MediaTek, Inc.
Bala Sivakumar Microsoft Corporation
Geert Knapen (Co-Chair & Editor) NXP Semiconductors
PL Mobile Audio
411 E. Plumeria drive
San Jose, CA 95134, USA
E-mail: geert.knapen@nxp.com
James Goel Qualcomm, Inc.
Andre Schevciw Qualcomm, Inc.
Jin-Sheng Wang Qualcomm, Inc.
Morten Christiansen Synopsys
REVISION HISTORY
Revision Date Filename Description
1.0 Mar. 18, 98 Frmts10.pdf Release 1.0
2.0 May. 31, 06 Frmts20 final.pdf Release 2.0
3.0 Sep. 22, 16 Frmts30.pdf Release 3.0
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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SIST EN IEC 62680-1-7:2020
IEC– 67 268– 0-1-7:2019 – 7 –
© USB-IF:1997-2016
Copyright © 1997-2016 USB Implementers Forum, Inc.
All rights reserved.
INTELLECTUAL PROPERTY DISCLAIMER
A LICENSE IS HEREBY GRANTED TO REPRODUCE THIS SPECIFICATION FOR INTERNAL USE ONLY. NO OTHER
LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, IS GRANTED OR INTENDED HEREBY.
USB-IF AND THE AUTHORS OF THIS SPECIFICATION EXPRESSLY DISCLAIM ALL LIABILITY FOR INFRINGEMENT OF
INTELLECTUAL PROPERTY RIGHTS RELATING TO IMPLEMENTATION OF INFORMATION IN THIS SPECIFICATION.
USB-IF AND THE AUTHORS OF THIS SPECIFICATION ALSO DO NOT WARRANT OR REPRESENT THAT SUCH
IMPLEMENTATION(S) WILL NOT INFRINGE THE INTELLECTUAL PROPERTY RIGHTS OF OTHERS.
THIS SPECIFICATION IS PROVIDED “AS IS” AND WITH NO WARRANTIES, EXPRESS OR IMPLIED, STATUTORY OR
OTHERWISE. ALL WARRANTIES ARE EXPRESSLY DISCLAIMED. USB-IF, ITS MEMBERS AND THE AUTHORS OF THIS
SPECIFICATION PROVIDE NO WARRANTY OF MERCHANTABILITY, NO WARRANTY OF NON-INFRINGEMENT, NO
WARRANTY OF FITNESS FOR ANY PARTICULAR PURPOSE, AND NO WARRANTY ARISING OUT OF ANY PROPOSAL,
SPECIFICATION, OR SAMPLE.
IN NO EVENT WILL USB-IF, MEMBERS OR THE AUTHORS BE LIABLE TO ANOTHER FOR THE COST OF PROCURING
SUBSTITUTE GOODS OR SERVICES, LOST PROFITS, LOSS OF USE, LOSS OF DATA OR ANY INCIDENTAL,
CONSEQUENTIAL, INDIRECT, OR SPECIAL DAMAGES, WHETHER UNDER CONTRACT, TORT, WARRANTY, OR
OTHERWISE, ARISING IN ANY WAY OUT OF THE USE OF THIS SPECIFICATION, WHETHER OR NOT SUCH PARTY
HAD ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.
NOTE: VARIOUS USB-IF MEMBERS PARTICIPATED IN THE DRAFTING OF THIS SPECIFICATION. CERTAIN OF
THESE MEMBERS MAY HAVE DECLINED TO ENTER INTO A SPECIFIC AGREEMENT LICENSING INTELLECTUAL
PROPERTY RIGHTS THAT MAY BE INFRINGED IN THE IMPLEMENTATION OF THIS SPECIFICATION. PERSONS
IMPLEMENT THIS SPECIFICATION AT THEIR OWN RISK.
Dolby™, AC-3™, Pro Logic™ and Dolby Surround™ are trademarks of Dolby Laboratories, Inc.
All other product names are trademarks, registered trademarks, or service marks of their respective owners.
Please send comments via electronic mail to audio-chair@usb.org
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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© USB-IF:1997-2016
TABLE OF CONTENTS
Scope of This Release . 6
Contributors . 6
Revision History . 6
Table of Contents . 8
List of Tables . 9
List of Figures . 10
1 Introduction . 10
1.1 Related Documents . 11
1.2 Terms and Abbreviations . 11
2 Audio Data Formats . 13
2.1 Transfer Delimiter . 14
2.2 Service Interval and Service Interval Packet Definitions . 14
2.3 Simple Audio Data Formats . 14
2.3.1 Type I Formats . 14
2.3.2 Type III Formats . 18
2.3.3 Type IV Formats . 19
2.4 Extended Audio Data Formats . 19
2.4.1 Extended Type I Formats . 20
2.4.2 Extended Type III Formats . 21
2.5 Class-specific AS Interface Descriptor . 21
3 Auxiliary Protocols . 23
3.1 HDCP Protocol . 23
4 Adding New Audio Data Formats . 24
5 Adding New Side Band Protocols . 25
Appendix A. Additional Audio Device Class Codes . 26
A.1 Audio Data Formats Bit Allocations . 26
A.2 SubHeader Codes . 27
A.3 Audio Format General Constants . 27
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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© USB-IF:1997-2016
LIST OF TABLES
Table 2-1: Packetization . 16
Table 2-2: SIPDescriptor Layout . 20
Table 2-3: Class-Specific AS Interface Descriptor . 22
Table 3-1: HDCP SubHeader Layout . 23
Table A-2: Audio Data Formats Bit Allocations in the bmFormats Field and Usage . 26
Table A-3: SubHeader Codes . 27
Table A-4: General Constants. 27
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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© USB-IF:1997-2016
LIST OF FIGURES
Figure 2-1: Type I Audio Stream . 13
Figure 2-2: Extended Type I Format . 21
Figure 2-3: Extended Type III Format . 21
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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SIST EN IEC 62680-1-7:2020
IEC– 611268 – 0-1-7:2019 – 11 –
© USB-IF:1997-2016
1 INTRODUCTION
The intention of this document is to describe in detail all the Audio Data Formats that are supported by the
Audio Device Class. This document is considered an integral part of the Audio Device Class Specification,
although subsequent revisions of this document are independent of the revision evolution of the main USB
Audio Specification. This is to easily accommodate the addition of new Audio Data Formats without impeding
the core USB Audio Specification.
1.1 RELATED DOCUMENTS
• Universal Serial Bus Specification, Revision 2.0 (referred to in this document as the USB Specification). In
particular, see Chapter 5, “USB Data Flow Model” and Chapter 9, “USB Device Framework.”
• Universal Serial Bus Device Class Definition for Audio Devices (referred to in this document as USB Audio
Device Class).
• Universal Serial Bus Device Class Definition for Terminal Types (referred to in this document as USB Audio
Terminal Types).
• ANSI S1.11-1986 standard.
• MPEG-1 standard ISO/IEC 111172-3 1993. (available from http://www.iso.ch )
• MPEG-2 standard ISO/IEC 13818-3 Feb. 20, 1997. (available from http://www.iso.ch)
• Digital Audio Compression Standard (AC-3), ATSC A/52A Aug. 20, 2001. (available from
http://www.atsc.org )
• Windows Media Audio (WMA) specification. (available from http://www.microsoft.com)
• ANSI/IEEE-754 floating-point standard.
• ISO/IEC 60958 International Standard: Digital Audio Interface and Annexes.
• ISO/IEC 61937 standard.
• ITU G.711 standard.
• ETSI Specification TS 102 114, “DTS Coherent Acoustics; Core and Extensions”. (Available from
http://webapp.etsi.org/action%5CPU/20020827/ts_102114v010101p.pdf)
1.2 TERMS AND ABBREVIATIONS
This section defines terms used throughout this document. For additional terms that pertain to the Universal
Serial Bus, see Chapter 2, “Terms and Abbreviations,” in the USB Specification.
AC-3 Audio compression standard from Dolby Labs.
Audio Slot A collection of audio subslots, each containing a PCM audio
sample of a different physical audio channel, taken at the same
moment in time.
Audio Stream A concatenation of a potentially very large number of audio
slots ordered according to ascending time.
Audio Subslot Holds a single PCM audio sample.
DTS Acronym for Digital Theater Systems.
DVD Acronym for Digital Versatile Disc.
Encoded Audio Bit Stream A concatenation of a potentially very large number of encoded
audio frames, ordered according to ascending time.
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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© USB-IF:1997-2016
Encoded Audio Frame A sequence of bits that contains an encoded representation of
audio samples from one or more physical audio channels taken
over a fixed period of time.
MPEG Acronym for Moving Pictures Expert Group.
PCM Acronym for Pulse Coded Modulation.
Service Interval A grouping of USB (micro)frames or Bus Intervals that are
related.
Service Interval Packet A packet that contains all the audio slots that are transferred
over the bus during a Service Interval.
Transfer Delimiter A unique token that indicates an interruption in an isochronous
data packet stream. Can be either a zero-length data packet or
the absence of an isochronous transfer in a certain USB frame.
WMA Acronym for Windows Media Audio.
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.
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© USB-IF:1997-2016
2 AUDIO DATA FORMATS
Audio Data formats can be divided in two main groups:
• Simple Audio Data Formats
• Extended Audio Data Formats
Simple Audio Data Formats can then be subdivided into three groups according to type.
The first group, Type I, deals with audio data streams that are transmitted over USB and are constructed on a
sample-by-sample basis. Each audio sample is represented by a single independent symbol, contained in an
audio subslot. Different compression schemes may be used to transform the audio samples into symbols.
Note: This is different from encoding. Compression is considered to take place on a per-audio-sample
base. Each audio sample generates one symbol (e.g. A-law compression where a 16-bit audio
sample is compressed into an 8-bit symbol).
If multiple physical audio channels are formatted into a single audio channel cluster, then samples at time x of
subsequent channels are first contained into audio subslots. These audio subslots are then interleaved,
according to the cluster channel ordering as described in the main USB Audio Specification, and then grouped
into an audio slot. The audio samples, taken at time x+1, are interleaved in the same fashion to generate the
next audio slot and so on. The notion of physical channels is explicitly preserved during transmission. A typical
example of Type I formats is the standard PCM audio data. The following figure illustrates the concept.
Figure 2-1: Type I Audio Stream
The second group, Type III, contains Audio Data Formats that use encapsulation as described in the ISO/IEC
61937 standard before being sent over USB. One or more non-PCM encoded audio data streams are packed
into “pseudo-stereo samples” and transmitted as if they were real stereo PCM audio samples. The sampling
frequency of these pseudo samples (transport sampling frequency, as reported by the Clock Frequency Control
of the associated Clock Source Entity) either matches the sampling frequency of the original non-encoded PCM
audio data streams (native sampling frequency) or there is an integer ratio relationship between them.
Therefore, clock recovery at the receiving end is relatively easy. The drawback is that unless multiple non-PCM
encoded streams are packed into one pseudo stereo stream, more bandwidth than necessary is consumed.
The third group, Type IV, deals with audio streams that are not transmitted over USB. Instead, they interface
with the Audio Function throu
...
SLOVENSKI STANDARD
oSIST prEN IEC 62680-1-7:2019
01-januar-2019
Vmesniki univerzalnega serijskega vodila za prenos podatkov in napajanje - 1-7.
del: Skupne komponente - USB Audio 3.0 Tip naprave za podatkovne formate
Universal serial bus interfaces for data and power - Part 1-7: Common components -
USB Audio 3.0 Device Class Definition Data Formats
Ta slovenski standard je istoveten z: prEN IEC 62680-1-7:2018
ICS:
35.200 Vmesniška in povezovalna Interface and interconnection
oprema equipment
oSIST prEN IEC 62680-1-7:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN IEC 62680-1-7:2019
---------------------- Page: 2 ----------------------
oSIST prEN IEC 62680-1-7:2019
100/3159/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 62680-1-7 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2018-11-23 2019-02-15
SUPERSEDES DOCUMENTS:
IEC TA 18 : MULTIMEDIA HOME SYSTEMS AND APPLICATIONS FOR END-USER NETWORKS
SECRETARIAT: SECRETARY:
Japan Mr Keisuke Koide
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of
which they are aware and to provide supporting documentation.
TITLE:
Universal serial bus interfaces for data and power - Part 1-7: Common components – USB Audio
3.0 Device Class Definition Data Formats
PROPOSED STABILITY DATE: 2022
NOTE FROM TC/SC OFFICERS:
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© USB-IF:1997-2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
UNIVERSAL SERIAL BUS INTERFACES FOR DATA AND POWER
Part 1-7: Common components – USB Audio 3.0 Device Class Definition
Data Formats
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62680-1-7 has been prepared by technical area 18: Multimedia
home systems and applications for end-user networks, of IEC technical committee 100: Audio,
video and multimedia systems and equipment.
The text of this standard was prepared by the USB Implementers Forum (USB-IF). The
structure and editorial rules used in this publication reflect the practice of the organization
which submitted it.
The text of this International Standard is based on the following documents:
FDIS Report on voting
XX/XX/FDIS XX/XX/RVD
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Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
The National Committees are requested to note that for this document the stability date
is .
THIS TEXT IS INCLUDED FOR THE INFORMATION OF THE NATIONAL COMMITTEES AND WILL BE
DELETED AT THE PUBLICATION STAGE.
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INTRODUCTION
The IEC 62680 series is based on a series of specifications that were originally developed by the USB
Implementers Forum (USB-IF). These specifications were submitted to the IEC under the auspices of
a special agreement between the IEC and the USB-IF.
This standard is the USB-IF publication USB Device Class Definition for Audio Data Formats Release
3.0.
The USB Implementers Forum, Inc.(USB-IF) is a non-profit corporation founded by the group of
companies that developed the Universal Serial Bus specification. The USB-IF was formed to provide a
support organization and forum for the advancement and adoption of Universal Serial Bus technology.
The Forum facilitates the development of high-quality compatible USB peripherals (devices), and
promotes the benefits of USB and the quality of products that have passed compliance testing.
ANY USB SPECIFICATIONS ARE PROVIDED TO YOU "AS IS, "WITH NO WARRANTIES
WHATSOEVER, INCLUDING ANY WARRANTY OF MERCHANTABILITY, NON-INFRINGEMENT,
OR FITNESS FOR ANY PARTICULAR PURPOSE. THE USB IMPLEMENTERS FORUM AND THE
AUTHORS OF ANY USB SPECIFICATIONS DISCLAIM ALL LIABILITY, INCLUDING LIABILITY
FOR INFRINGEMENT OF ANY PROPRIETARY RIGHTS, RELATING TO USE OR
IMPLEMENTATION OR INFORMATION IN THIS SPECIFICAITON.
THE PROVISION OF ANY USB SPECIFICATIONS TO YOU DOES NOT PROVIDE YOU WITH ANY
LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL
PROPERTY RIGHTS.
Entering into USB Adopters Agreements may, however, allow a signing company to participate in a
reciprocal, RAND-Z licensing arrangement for compliant products. For more information, please see:
https://www.usb.org/documents
IEC DOES NOT TAKE ANY POSITION AS TO WHETHER IT IS ADVISABLE FOR YOU TO ENTER
INTO ANY USB ADOPTERS AGREEMENTS OR TO PARTICIPATE IN THE USB IMPLEMENTERS
FORUM.”
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UNIVERSAL SERIAL BUS
DEVICE CLASS DEFINITION
FOR
AUDIO DATA FORMATS
Release 3.0
September 22, 2016
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1 SCOPE OF THIS RELEASE
2 This document is the Release 3.0 of this device class definition.
3 CONTRIBUTORS
4 Joe Scanlon Advanced Micro Devices
5 Rhoads Hollowell Apple Inc.
6 Girault Jones Apple Inc.
7 Matthew X. Mora Apple Inc.
8 Tzung-Dar Tsai C-Media Electronics, Inc.
9 Brad Lambert Cirrus Logic, Inc.
10 Dan Bogard Conexant Systems, Inc.
11 Pete Burgers DisplayLink (UK), Ltd.
12 David Roh Dolby Laboratories, Inc.
13 Leng Ooi Google, Inc.
14 Pierre-Louis Bossart Intel Corporation
15 David Hines Intel Corporation
16 Abdul Rahman Ismail (Co-Chair) Intel Corporation
17 Devon Worrell Intel Corporation
18 Chandrashekhar Rao Logitech, Inc.
19 Terry Moore MCCI Corporation
20 Alex Lin MediaTek, Inc.
21 Bala Sivakumar Microsoft Corporation
22 Geert Knapen (Co-Chair & Editor) NXP Semiconductors
23 PL Mobile Audio
24 411 E. Plumeria drive
25 San Jose, CA 95134, USA
26 E-mail: geert.knapen@nxp.com
27 James Goel Qualcomm, Inc.
28 Andre Schevciw Qualcomm, Inc.
29 Jin-Sheng Wang Qualcomm, Inc.
30 Morten Christiansen Synopsys
31 REVISION HISTORY
Revision Date Filename Description
1.0 Mar. 18, 98 Frmts10.pdf Release 1.0
2.0 May. 31, 06 Frmts20 final.pdf Release 2.0
3.0 Sep. 22, 16 Frmts30.pdf Release 3.0
32
33
34
35
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36 Copyright © 1997-2016 USB Implementers Forum, Inc.
37 All rights reserved.
38
39 INTELLECTUAL PROPERTY DISCLAIMER
40 A LICENSE IS HEREBY GRANTED TO REPRODUCE THIS SPECIFICATION FOR INTERNAL USE ONLY. NO OTHER
41 LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, IS GRANTED OR INTENDED HEREBY.
42 USB-IF AND THE AUTHORS OF THIS SPECIFICATION EXPRESSLY DISCLAIM ALL LIABILITY FOR INFRINGEMENT OF
43 INTELLECTUAL PROPERTY RIGHTS RELATING TO IMPLEMENTATION OF INFORMATION IN THIS SPECIFICATION.
44 USB-IF AND THE AUTHORS OF THIS SPECIFICATION ALSO DO NOT WARRANT OR REPRESENT THAT SUCH
45 IMPLEMENTATION(S) WILL NOT INFRINGE THE INTELLECTUAL PROPERTY RIGHTS OF OTHERS.
46 THIS SPECIFICATION IS PROVIDED “AS IS” AND WITH NO WARRANTIES, EXPRESS OR IMPLIED, STATUTORY OR
47 OTHERWISE. ALL WARRANTIES ARE EXPRESSLY DISCLAIMED. USB-IF, ITS MEMBERS AND THE AUTHORS OF THIS
48 SPECIFICATION PROVIDE NO WARRANTY OF MERCHANTABILITY, NO WARRANTY OF NON-INFRINGEMENT, NO
49 WARRANTY OF FITNESS FOR ANY PARTICULAR PURPOSE, AND NO WARRANTY ARISING OUT OF ANY PROPOSAL,
50 SPECIFICATION, OR SAMPLE.
51 IN NO EVENT WILL USB-IF, MEMBERS OR THE AUTHORS BE LIABLE TO ANOTHER FOR THE COST OF PROCURING
52 SUBSTITUTE GOODS OR SERVICES, LOST PROFITS, LOSS OF USE, LOSS OF DATA OR ANY INCIDENTAL,
53 CONSEQUENTIAL, INDIRECT, OR SPECIAL DAMAGES, WHETHER UNDER CONTRACT, TORT, WARRANTY, OR
54 OTHERWISE, ARISING IN ANY WAY OUT OF THE USE OF THIS SPECIFICATION, WHETHER OR NOT SUCH PARTY
55 HAD ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.
56 NOTE: VARIOUS USB-IF MEMBERS PARTICIPATED IN THE DRAFTING OF THIS SPECIFICATION. CERTAIN OF
57 THESE MEMBERS MAY HAVE DECLINED TO ENTER INTO A SPECIFIC AGREEMENT LICENSING INTELLECTUAL
58 PROPERTY RIGHTS THAT MAY BE INFRINGED IN THE IMPLEMENTATION OF THIS SPECIFICATION. PERSONS
59 IMPLEMENT THIS SPECIFICATION AT THEIR OWN RISK.
60 Dolby™, AC-3™, Pro Logic™ and Dolby Surround™ are trademarks of Dolby Laboratories, Inc.
61 All other product names are trademarks, registered trademarks, or service marks of their respective owners.
62 Please send comments via electronic mail to audio-chair@usb.org
63
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64 TABLE OF CONTENTS
65 Scope of This Release . 1
66 Contributors . 1
67 Revision History . 1
68 Table of Contents . 3
69 List of Tables . 4
70 List of Figures . 5
71 1 Introduction . 5
72 1.1 Related Documents . 6
73 1.2 Terms and Abbreviations . 6
74 2 Audio Data Formats . 8
75 2.1 Transfer Delimiter . 9
76 2.2 Service Interval and Service Interval Packet Definitions . 9
77 2.3 Simple Audio Data Formats . 9
78 2.3.1 Type I Formats . 9
79 2.3.2 Type III Formats . 13
80 2.3.3 Type IV Formats . 14
81 2.4 Extended Audio Data Formats . 14
82 2.4.1 Extended Type I Formats . 15
83 2.4.2 Extended Type III Formats . 16
84 2.5 Class-specific AS Interface Descriptor . 16
85 3 Auxiliary Protocols . 18
86 3.1 HDCP Protocol . 18
87 4 Adding New Audio Data Formats . 19
88 5 Adding New Side Band Protocols . 20
89 Appendix A. Additional Audio Device Class Codes . 21
90 Audio Data Formats Bit Allocations . 21
A.1
91 A.2 SubHeader Codes . 22
92 A.3 Audio Format General Constants . 22
93
94
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95 LIST OF TABLES
96 Table 2-1: Packetization . 11
97 Table 2-1: SIPDescriptor Layout . 15
98 Table 2-2: Class-Specific AS Interface Descriptor . 17
99 Table 3-1: HDCP SubHeader Layout . 18
100 Table A-2: Audio Data Formats Bit Allocations in the bmFormats Field and Usage . 21
101 Table A-3: SubHeader Codes . 22
102 Table A-4: General Constants. 22
103
104
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105 LIST OF FIGURES
106 Figure 2-1: Type I Audio Stream . 8
107 Figure 2-2: Extended Type I Format . 16
108 Figure 2-3: Extended Type III Format . 16
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109 1 INTRODUCTION
110 The intention of this document is to describe in detail all the Audio Data Formats that are supported by the
111 Audio Device Class. This document is considered an integral part of the Audio Device Class Specification,
112 although subsequent revisions of this document are independent of the revision evolution of the main USB
113 Audio Specification. This is to easily accommodate the addition of new Audio Data Formats without impeding
114 the core USB Audio Specification.
115 1.1 RELATED DOCUMENTS
116 • Universal Serial Bus Specification, Revision 2.0 (referred to in this document as the USB Specification). In
117 particular, see Chapter 5, “USB Data Flow Model” and Chapter 9, “USB Device Framework.”
118 • Universal Serial Bus Device Class Definition for Audio Devices (referred to in this document as USB Audio
119 Device Class).
120 • Universal Serial Bus Device Class Definition for Terminal Types (referred to in this document as USB Audio
121 Terminal Types).
122 • ANSI S1.11-1986 standard.
123 • MPEG-1 standard ISO/IEC 111172-3 1993. (available from http://www.iso.ch )
124 • MPEG-2 standard ISO/IEC 13818-3 Feb. 20, 1997. (available from http://www.iso.ch)
125 • Digital Audio Compression Standard (AC-3), ATSC A/52A Aug. 20, 2001. (available from
126 http://www.atsc.org )
127 • Windows Media Audio (WMA) specification. (available from http://www.microsoft.com)
128 • ANSI/IEEE-754 floating-point standard.
129 • ISO/IEC 60958 International Standard: Digital Audio Interface and Annexes.
130 • ISO/IEC 61937 standard.
131 • ITU G.711 standard.
132 • ETSI Specification TS 102 114, “DTS Coherent Acoustics; Core and Extensions”. (Available from
133 http://webapp.etsi.org/action%5CPU/20020827/ts_102114v010101p.pdf)
134
135 1.2 TERMS AND ABBREVIATIONS
136 This section defines terms used throughout this document. For additional terms that pertain to the Universal
137 Serial Bus, see Chapter 2, “Terms and Abbreviations,” in the USB Specification.
138 AC-3 Audio compression standard from Dolby Labs.
139 Audio Slot A collection of audio subslots, each containing a PCM audio
140 sample of a different physical audio channel, taken at the same
141 moment in time.
142 Audio Stream A concatenation of a potentially very large number of audio
143 slots ordered according to ascending time.
144 Audio Subslot Holds a single PCM audio sample.
145 DTS Acronym for Digital Theater Systems.
146 DVD Acronym for Digital Versatile Disc.
147 Encoded Audio Bit Stream A concatenation of a potentially very large number of encoded
148 audio frames, ordered according to ascending time.
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149 Encoded Audio Frame A sequence of bits that contains an encoded representation of
150 audio samples from one or more physical audio channels taken
151 over a fixed period of time.
152 MPEG Acronym for Moving Pictures Expert Group.
153 PCM Acronym for Pulse Coded Modulation.
154 Service Interval A grouping of USB (micro)frames or Bus Intervals that are
155 related.
156 Service Interval Packet A packet that contains all the audio slots that are transferred
157 over the bus during a Service Interval.
158 Transfer Delimiter A unique token that indicates an interruption in an isochronous
159 data packet stream. Can be either a zero-length data packet or
160 the absence of an isochronous transfer in a certain USB frame.
161 WMA Acronym for Windows Media Audio.
162
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163 2 AUDIO DATA FORMATS
164 Audio Data formats can be divided in two main groups:
165 • Simple Audio Data Formats
166 • Extended Audio Data Formats
167 Simple Audio Data Formats can then be subdivided into three groups according to type.
168 The first group, Type I, deals with audio data streams that are transmitted over USB and are constructed on a
169 sample-by-sample basis. Each audio sample is represented by a single independent symbol, contained in an
170 audio subslot. Different compression schemes may be used to transform the audio samples into symbols.
171 Note: This is different from encoding. Compression is considered to take place on a per-audio-sample
172 base. Each audio sample generates one symbol (e.g. A-law compression where a 16-bit audio
173 sample is compressed into an 8-bit symbol).
174 If multiple physical audio channels are formatted into a single audio channel cluster, then samples at time x of
175 subsequent channels are first contained into audio subslots. These audio subslots are then interleaved,
176 according to the cluster channel ordering as described in the main USB Audio Specification, and then grouped
177 into an audio slot. The audio samples, taken at time x+1, are interleaved in the same fashion to generate the
178 next audio slot and so on. The notion of physical channels is explicitly preserved during transmission. A typical
179 example of Type I formats is the standard PCM audio data. The following figure illustrates the concept.
180 Figure 2-1: Type I Audio Stream
181
182 The second group, Type III, contains Audio Data Formats that use encapsulation as described in the ISO/IEC
183 61937 standard before being sent over USB. One or more non-PCM encoded audio data streams are packed
184 into “pseudo-stereo samples” and transmitted as if they were real stereo PCM audio samples. The sampling
185 frequency of these pseudo samples (transport sampling frequency, as reported by the Clock Frequency Control
186 of the associated Clock Source Entity) either matches the sampling frequency of the original non-encoded PCM
187 audio data streams (native sampling frequency) or there is an integer ratio relationship between them.
188 Therefore, clock recovery at the receiving end is relatively easy. The drawback is that unless multiple non-PCM
189 encoded streams are packed into one pseudo stereo stream, more bandwidth than necessary is consumed.
190 The third group, Type IV, deals with audio streams that are not transmitted over USB. Instead, they interface
191 with the Audio Function through an AudioStreaming interface that does not contain a USB isochronous IN or
192 OUT endpoint. These streams typically connect via a digital interface like S/PDIF (or some other means of
193 connectivity) and may require interaction from the Host before they enter or leave the Audio Function. A
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194 typical example is an external S/PDIF connector that can accept an AC-3 encoded audio stream. This stream is
195 first processed by an AC-3 decoder before the (decoded) logical audio channels enter the Audio Function
196 through the Input Terminal that represents this S/PDIF connection.
197 In addition to the Simple Audio Data Formats described above, Extended Audio Data Formats are defined.
198 These are based on the Simple Audio Data Formats Type I and III definitions but they provide an optional
199 packet header and for the Extended Audio Data Format Type I, an optional synchronous (i.e. sample accurate)
200 control channel. Type IV Audio Data Formats do not have an Extended Audio Data Format definition.
201 The following sections explain the different Audio Data Formats and Format Types in more detail.
202 2.1 TRANSFER DELIMITER
203 Isochronous data streams are continuous in nature, although the actual number of bytes sent per packet may
204 vary throughout the lifetime of the stream (for rate adaptation purposes for instance). To indicate a temporary
205 stop in the isochronous data stream without closing the pipe (and thus relinquishing the USB bandwidth), an in-
206 band Transfer Delimiter needs to be defined. This specification considers two situations to be a Transfer
207 Delimiter. The first is a zero-length data packet and the second is the absence of an isochronous transfer in a
208 USB (micro)frame that would normally have an isochronous transfer. Both situations are considered equivalent
209 and the Audio Function is expected to behave the same. However, the second type consumes less isochronous
210 USB bandwidth (i.e. zero bandwidth). In both cases, this specification considers a Transfer Delimiter to be an
211 entity that can be sent over the USB.
212 2.2 SERVICE INTERVAL AND SERVICE INTERVAL PACKET DEFINITIONS
213 Note: The USB Audio 2.0 Specification used the terms Virtual Frame and Virtual Frame Packet t
...
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