IEC 62680-1-8:2019

Universal serial bus interfaces for data and power - Part 1-8: Common components - USB Audio 3.0 device class definition terminal types

IEC 62680-1-8:2019 is to describe in detail all the Terminal Types 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 Audio Device Class Specification. This is to easily accommodate the addition of new Terminal Types without impeding the core Audio Device Class Specification.
The Audio Device Class Definition applies to all devices or functions embedded in composite devices. All audio signals inside an audio function start at an Input Terminal, pass through some Units, and leave the function through an Output Terminal. Units can manipulate the signal in various ways. Terminals represent the connections of the function to the outside world.
As part of the Terminal descriptor, the wTerminalType field specifies the vendor’s suggested use of the Terminal. For example, a pair of speakers is a more suitable target for music output than a telephone line. This feature allows a vendor to ensure that applications use the device in a consistent and meaningful way.

Interfaces de bus universel en série pour les données et l'alimentation électrique - Partie 1-8: Composants communs - Définition de classes de dispositifs USB Audio 3.0 pour types de terminaux

L'IEC 62680-1-8:2019 a pour objectif de décrire en détail tous les types de terminaux 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 de classe de dispositifs audio principale. L'objectif est de faciliter la prise en compte de l'ajout de nouveaux types de terminaux sans affecter la Spécification de classe de dispositifs audio de base.
La définition de classes de dispositifs audio s'applique à tous les dispositifs ou fonctions intégrés dans des dispositifs composites. Tous les signaux audio au sein d'une fonction audio partent d'un terminal d'entrée, passent par des unités, puis quittent la fonction par un terminal de sortie. Les unités peuvent manipuler le signal de différentes façons. Les terminaux représentent les connexions de la fonction au monde extérieur.
Le champ wTerminalType, qui fait partie du descripteur de terminal, indique l'utilisation suggérée par le fournisseur du terminal. Par exemple, une paire de haut-parleurs est une cible plus appropriée pour une sortie musicale qu'une ligne téléphonique. Cette fonctionnalité permet à un fournisseur de s'assurer que les applications utilisent le dispositif de manière cohérente et pertinente.

General Information

• Status: Published
• Publication Date: 18-Sep-2019
• ICS: 33.120.20 - Wires and symmetrical cables
• ICS: 33.120.30 - RF connectors
• ICS: 35.200 - Interface and interconnection equipment
• Technical Committee: TA 18 - Multimedia home systems and applications for end-user networks
• Current Stage: PPUB - Publication issued
• Start Date: 28-Aug-2019
• Completion Date: 19-Sep-2019

Standards Content (Sample)

IEC 62680-1-8 ®
Edition 1.0 2019-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Universal serial bus interfaces for data and power –
Part 1-8: Common components – USB Audio 3.0 device class definition terminal
types
Interfaces de bus universel en série pour les données et l'alimentation
électrique –
Partie 1-8: Composants communs – Définition de classes de dispositifs USB
Audio 3.0 pour types de terminaux

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IEC 62680-1-8 ®
Edition 1.0 2019-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Universal serial bus interfaces for data and power –

Part 1-8: Common components – USB Audio 3.0 device class definition terminal

types
Interfaces de bus universel en série pour les données et l'alimentation

électrique –
Partie 1-8: Composants communs – Définition de classes de dispositifs USB

Audio 3.0 pour types de terminaux

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.120.20; 33.120.30; 35.200 ISBN 978-2-8322-7245-9

– 2 – IEC 62680-1-8:2019
© USB-IF:1997-2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
UNIVERSAL SERIAL BUS INTERFACES FOR DATA AND POWER –

Part 1-8: Common components –
USB Audio 3.0 device class definition terminal types

FOREWORD
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62680-1-8 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.
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–IE 3C – 6 2680-1-8:2019 – 3 –
© USB-IF:1997-2016
The text of this International Standard is based on the following documents:
CDV Report on voting
100/3160/CDV 100/3230/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.
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.
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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 Terminal Types 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
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INTO ANY USB ADOPTERS AGREEMENTS OR TO PARTICIPATE IN THE USB IMPLEMENTERS
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–IE 5C – 6 2680-1-8:2019 – 5 –
© USB-IF:1997-2016
UNIVERSAL SERIAL BUS
DEVICE CLASS DEFINITION
FOR
TERMINAL TYPES
Release 3.0
September 22, 2016
Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.

– 6 – IEC 62680-1-8:2019
© 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: [e-mail]
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 Termt10.pdf Release 1.0
2.0 May. 31, 06 Termt20 final.pdf Release 2.0
3.0 Sep. 22, 16 Termt30.pdf Release 3.0

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–IE 7C – 6 2680-1-8:2019 – 7 –
© USB-IF:1997-2016
Copyright © 1997-2016 USB Implementers Forum, Inc.
All rights reserved.
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SPECIFICATION PROVIDE NO WARRANTY OF MERCHANTABILITY, NO WARRANTY OF NON-INFRINGEMENT, NO
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HAD ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.
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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 [e-mail]

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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
1 Introduction . 10
1.1 Scope . 10
1.2 Related Documents . 10
1.3 Terms and Abbreviations . 10
2 Terminal Types . 11
2.1 USB Terminal Types . 11
2.2 Input Terminal Types. 11
2.3 Output Terminal Types . 12
2.4 Bi-directional Terminal Types . 12
2.5 Telephony Terminal Types . 13
2.6 External Terminal Types . 13
2.7 Embedded Function Terminal Types . 14
3 Adding New Terminal Types . 15

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–IE 9C – 6 2680-1-8:2019 – 9 –
© USB-IF:1997-2016
LIST OF TABLES
Table 2-1: USB Terminal Types. 11
Table 2-2: Input Terminal Types . 11
Table 2-3: Output Terminal Types. 12
Table 2-4: Bi-directional Terminal Types. 12
Table 2-5: Telephony Terminal Types . 13
Table 2-6: External Terminal Types . 13
Table 2-7: Embedded Terminal Types . 14

Copyright © 1997-2016 USB Implementers Forum, Inc. All rights reserved.

– 10 – IEC 62680-1-8:2019
© USB-IF:1997-2016
1 INTRODUCTION
The intention of this document is to describe in detail all the Terminal Types 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 Audio Device
Class Specification. This is to easily accommodate the addition of new Terminal Types without impeding the
core Audio Device Class Specification.
1.1 SCOPE
The Audio Device Class Definition applies to all devices or functions embedded in composite devices. All audio
signals inside an audio function start at an Input Terminal, pass through some Units, and leave the function
through an Output Terminal. Units can manipulate the signal in various ways. Terminals represent the
connections of the function to the outside world.
As part of the Terminal descriptor, the wTerminalType field specifies the vendor’s suggested use of the
Terminal. For example, a pair of speakers is a more suitable target for music output than a telephone line. This
feature allows a vendor to ensure that applications use the device in a consistent and meaningful way.
1.2 RELATED DOCUMENTS
• Universal Serial Bus Specification, 1.0 final draft revision (also referred to as the USB Specification). In
particular, see Chapter 9, “USB Device Framework”.
• Universal Serial Bus Device Class Definition for Audio Data Formats (referred to in this document as USB
Audio Data Formats).
• ANSI S1.11-1986 standard.
• AES10-2003 AES Recommended Practice for Digital Audio Engineering – Serial Multichannel Audio Digital
Interface (MADI)
• MPEG-1 standard ISO/IEC 111172-3 1993.
• MPEG-2 standard ISO/IEC 13818-3 Feb. 20, 1997.
• Digital Audio Compression Standard (AC-3), ATSC A/52 Dec. 20, 1995. (available from http://www.atsc.org)
• ANSI/IEEE-754 floating-point standard.
• ISO/IEC 958 International Standard: Digital Audio Interface and Annexes.
• ISO/IEC 1937 standard.
• ITU G.711 standard.
1.3 TERMS AND ABBREVIATIONS
None.
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–IE 11C 6 –268 0-1-8:2019 – 11 –
© USB-IF:1997-2016
2 TERMINAL TYPES
The following is a list of possible Terminal Types. This list is non-exhaustive and will only be expanded in the
future.
2.1 USB TERMINAL TYPES
These Terminal Types describe Terminals that handle signals carried over the USB, usually through isochronous
pipes. These Terminal Types are valid for both Input and Output Terminals.
Table 2-1: USB Terminal Types
Terminal Type Code I/O Description
USB Undefined 0x0100 I/O USB Terminal, undefined Type.
A Terminal dealing with a signal carried over
USB streaming 0x0101 I/O
an endpoint in an AudioStreaming interface.
The AudioStreaming interface descriptor
points to the associated Terminal through the
bTerminalLink field.
USB vendor specific 0x01FF I/O A Terminal dealing with a signal carried over a
vendor-specific interface. The vendor-specific
interface descriptor must contain a field that
references the Terminal.
2.2 INPUT TERMINAL TYPES
These Terminal Types describe Terminals that are designed to record sounds. They either are physically part of
the audio function or can be assumed to be connected to it in normal operation. These Terminal Types are
valid only for Input Terminals
Table 2-2: Input Terminal Types
Terminal Type Code I/O Description
Input Undefined 0x0200 I Input Terminal, undefined Type.
Microphone 0x0201 I A generic microphone that does not fit under
any of the other classifications.
Desktop microphone 0x0202 I A microphone normally placed on the
desktop or integrated into the monitor.
Personal microphone 0x0203 I A head-mounted or clip-on microphone.
Omni-directional microphone 0x0204 I A microphone designed to pick up voice from
more than one speaker at relatively long
ranges.
Microphone array 0x0205 I An array of microphones designed for
directional processing using host-based signal
processing algorithms.
Processing microphone array 0x0206 I An array of microphones with an embedded
signal processor.
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– 12 – IEC 62680-1-8:2019
© USB-IF:1997-2016
2.3 OUTPUT TERMINAL TYPES
These Terminal Types describe Terminals that produce audible signals that are intended to be heard by the
user of the audio function. They either are physically part of the audio function or can be assumed to be
connected to it in normal operation. These Terminal Types are only valid for Output Terminals. The distinction
between headphones, desktop speakers, and room speakers may be used by applications to select different 3D
signal processing algorithms.
Table 2-3: Output Terminal Types
Terminal Type Code I/O Description
Output Undefined 0x0300 O Output Terminal, undefined Type.
Speaker 0x0301 O A generic speaker or set of speakers that does
not fit under any of the other classifications.
Headphones 0x0302 O A head-mounted audio output device.
Head Mounted Display Audio 0x0303 O The audio part of a VR head mounted display.
The Associated Interfaces descriptor can be
used to reference the HID interface used to
report the position and orientation of the
HMD.
Desktop speaker 0x0304 O Relatively small speaker or set of speakers
normally placed on the desktop or integrated
into the monitor. These speakers are close to
the user and have limited stereo separation.
Room speaker 0x0305 O Larger speaker or set of speakers that are
heard well anywhere in the room.
Communication speaker 0x0306 O Speaker or set of speakers designed for voice
communication.
Low frequency effects speaker 0x0307 O Speaker designed for low frequencies
(subwoofer). Not capable of reproducing
speech or music.
2.4 BI-DIRECTIONAL TERMINAL TYPES
These Terminal Types describe an Input and an Output Terminal for voice communication that are closely
related. They should be used together for bi-directional voice communication. They may be used separately for
input only or output only. These types require two Terminal descriptors. Both have the same type. The two
Terminals are linked together through the bAssocTerminal fields in their respective Terminal descriptors. The
Associated Interfaces descriptor can be used to reference a HID interface for conferencing functions.
Table 2-4: Bi-directional Terminal Types
Terminal Type Code I/O Description
Bi-directional Undefined 0x0400 I/O Bi-directional Terminal, undefined Type.
Handset 0x0401 I/O Hand-held bi-directional audio device.
Headset 0x0402 I/O Head-mounted bi-directional audio device.
Speakerphone, no echo reduction 0x0403 I/O A hands-free audio device designed for host-
based echo cancellation.
Echo-suppressing speakerphone 0x0404 I/O A hands-free audio device with echo
suppression capable of half-duplex operation.
Echo-canceling speakerphone 0x0405 I/O A hands-free audio device with echo
cancellation capable of full-duplex operation.
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–IE 13C 6 –268 0-1-8:2019 – 13 –
© USB-IF:1997-2016
2.5 TELEPHONY TERMINAL TYPES
These Terminal Types describe Terminals that connect to the PSTN or PBX. Initiating calls and monitoring call
progress will be done through an associated interface which may be Communication, HID or Vendor-Specific
class. These Terminals are bi-directional and follow the rules for bi-directional Terminals.
Table 2-5: Telephony Terminal Types
Terminal Type Code I/O Description
Telephony Undefined 0x0500 I/O Telephony Terminal, undefined Type.
Phone line 0x0501 I/O May be an analog telephone line jack, an ISDN
line, a proprietary PBX interface, or a wireless
link.
Telephone 0x0502 I/O Device can be used as a telephone. When not
in use as a telephone, handset is used as a bi-
directional audio device.
Down Line Phone 0x0503 I/O A standard telephone set connected to the
device. When not in use as a telephone, it can
be used as a bi-directional audio device.
2.6 EXTERNAL TERMINAL TYPES
These Terminal Types describe external resources and connections that do not fit under the categories of Input
or Output Terminals because they do not necessarily translate acoustic signals to or from the user of the
computer. Most of them may be either Input or Output Terminals.
Table 2-6: External Terminal Types
Terminal Type Code I/O Description
External Undefined 0x0600 I/O External Terminal, undefined Type.
Analog connector 0x0601 I/O A generic analog connector.
Digital audio interface 0x0602 I/O A generic digital audio interface.
Line connector 0x0603 I/O An analog connector at standard line levels.
Usually uses 3.5mm.
An input connector assumed to be connected
Legacy audio connector 0x0604 I/O
to the lineout of the legacy audio system of
the host computer. Used for backward
compatibility.
S/PDIF interface 0x0605 I/O An S/PDIF digital audio interface. The
Associated Interface descriptor can be used
to reference an interface used for controlling
special functions of this interface.
1394 DA stream 0x0606 I/O An interface to audio streams on a 1394 bus.
1394 DV stream soundtrack 0x0607 I/O An interface to soundtrack of A/V stream on a
1394 bus.
ADAT Lightpipe 0x0608 I/O An optical connection carrying the Alesis
Digital Audio Tape stream. Contact Alesis for
technical information.
TDIF 0x0609 I/O Tascam Digital Interface. Contact Tascam for
technical information.
MADI 0x060A I/O Multi-channel Audio Digital Interface as
defined by AES.
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– 14 – IEC 62680-1-8:2019
© USB-IF:1997-2016
2.7 EMBEDDED FUNCTION TERMINAL TYPES
These Terminal Types represent connections to internal audio sources or sinks in a device. All have associated
interfaces for control. These interfaces may be HID or other classes (vendor-specific, mass storage for CD-ROM,
etc.). Devices capable of both playback and recording should follow the rules for bi-directional Terminals.
Table 2-7: Embedded Terminal Types
Terminal Type Code I/O Description
Embedded Undefined 0x0700 I/O Embedded Terminal, undefined Type.
Level Calibration Noise Source 0x0701 O Internal Noise source for level calibration
(MPEG decoding, Dolby Prologic, AC-3 etc.)
Equalization Noise 0x0702 O Internal Noise source for measurements.
CD player 0x0703 I Audio compact disc player or CD-ROM
capable of audio playback.
DAT 0x0704 I/O Digital Audio Tape.
DCC 0x0705 I/O Digital Compact Cassette.
Compressed Audio Player 0x0706 I/O Compressed Audio player.
Analog Tape 0x0707 I/O Analog Audio Tape.
Phonograph 0x0708 I Analog vinyl record player.
VCR Audio 0x0709 I Audio track of VCR.
Video Disc Audio 0x070A I Audio track of VideoDisc player.
DVD Audio 0x070B I Audio track of DVD player.
TV Tuner Audio 0x070C I Audio track of TV tuner.
Satellite Receiver Audio 0x070D I Audio track of satellite receiver.
Cable Tuner Audio 0x070E I Audio track of cable tuner.
DSS Audio 0x070F I Audio track of DSS receiver.
Radio Receiver 0x0710 I AM/FM radio receiver.
Radio Transmitter 0x0711 O AM/FM radio transmitter.
Multi-track Recorder 0x0712 I/O A multi-track recording system.
Synthesizer 0x0713 I/O Synthesizer.
Piano 0x0714 I/O Piano
Guitar 0x0715 I/O Guitar
Drums/Rhythm 0x0716 I/O Percussion Instrument
Other Musical Instrument 0x0717 I/O Undefined Musical Instrument
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–IE 15C 6 –268 0-1-8:2019 – 15 –
© USB-IF:1997-2016
3 ADDING NEW TERMINAL TYPES
Adding new Terminal Types to this specification is achieved by proposing a fully documented Terminal Type to
the Audio Device Class Working Group. Upon acceptance, the group will register the new Terminal Type
(attribute a unique Terminal Type Code) and update this document accordingly. This process will also
guarantee that new releases of generic USB audio drivers will support the newly registered Terminal Types.
It is always possible to use vendor-specific definitions if the above procedure is consid
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