IEC 60958-1:2004

IEC 60958-1 ®
Edition 2.0 2004-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Digital audio interface –
Part 1: General
Interface audionumérique –
Partie 1: Généralités
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IEC 60958-1 ®
Edition 2.0 2004-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Digital audio interface –
Part 1: General
Interface audionumérique –
Partie 1: Généralités
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX R
ICS 33.160.01 ISBN 978-2-8322-0892-2

– 2 – 60958-1  IEC:2004
CONTENTS
FOREWORD . 3

1 Scope . 5
2 Normative references. 5
3 Terms and definitions . 5
4 Interface format . 7
4.1 Structure of format . 7
4.2 Channel coding . 8
4.3 Preambles . 9
4.4 Validity bit . 10
5 Channel status . 10
5.1 General . 10
5.2 Applications . 10
5.3 General assignment of the first and second channel status bits . 11
5.4 Category code . 11
6 User data . 13
6.1 General . 13
6.2 Applications . 13
7 Electrical requirements . 13

Annex A (informative) The use of the validity bit . 14
Annex B (informative) Application documents and specifications . 15
Annex C (informative) A relationship of IEC 60958 families . 16
Annex D (informative) Transmission of CD data other than linear PCM audio . 17

Bibliography . 18

Table 1 – Preamble coding . 9
Table 2 – Channel status data format . 12
Table B1 – Application documents and specifications . 15

60958-1  IEC:2004 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIGITAL AUDIO INTERFACE –
Part 1: General
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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
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
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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.
IEC 60958-1, edition 2 has been prepared by Technical Area 4, Digital system interfaces, of
IEC technical committee 100: Audio, video and multimedia systems and equipment.
This second edition of IEC 60958-1 cancels and replaces the first edition published in 1999 and
constitutes a technical revision.
All changes introduced in this second edition of IEC 60958-1 intend to clarify the structure and
the relationship between all of IEC 60958 series families.
A brief list of changes include:
• Annex B has been added to explain the definition given in 5.3 with relation of the families of
the IEC 60958 series. Clause 5.3 is also added to this description.
• Annex C has been added to explain the relationship of the IEC 60958 series families.
• Annex D has been added as an explanation for a data transmission other than linear PCM.
• Subclause 5.4 has been added to define category code appliance.
• A Bibliography has been added.

– 4 – 60958-1  IEC:2004
This bilingual version (2013-07) corresponds to the monolingual English version, published in
2004-03.
The text of this standard is based on the following documents:
CDV Report on voting
100/552/CDV 100/755/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
The French version of this standard has not been voted upon.This publication has been drafted
in accordance with the ISO/IEC Directives, Part 2.
IEC 60958 consists of the following parts under the general title Digital audio interface:
Part 1: General
Part 3: Consumer applications
Part 4: Professional applications
The committee has decided that the contents of this publication will remain unchanged until
2006. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
60958-1  IEC:2004 – 5 –
DIGITAL AUDIO INTERFACE –
Part 1: General
1 Scope
This part of IEC 60958 describes a serial, uni-directional, self-clocking interface for the
interconnection of digital audio equipment for consumer and professional applications.
It specifies the basic structure of the interface. Separate documents define items specific to
particular applications.
The interface is primarily intended to carry monophonic or stereophonic programmes, encoded
using linear PCM and with a resolution of up to 24 bits per sample.
When used for other purposes, the interface is able to carry audio data coded other than as
linear PCM coded audio samples. Provision is also made to allow the interface to carry data
related to computer software or signals coded using non-linear PCM. The format specification
for these applications is not part of this standard.
The interface is intended for operation at audio sampling frequencies of 32 kHz and above.
Auxiliary information is transmitted along with the programme.
2 Normative references
The following referenced documents are indispensable for the application of this document. For
dated references, only the edition cited applies. For undated references, the latest edition of
the referenced document (including any amendments) applies.
IEC 60958-3, Digital audio Interface – Part 3: Consumer applications
IEC 60958-4, Digital audio Interface – Part 4: Professional applications
3 Terms and definitions
For the purpose of all parts of the IEC 60958 series, the following terms and definitions apply.
3.1
sampling frequency
frequency of the samples representing an audio signal
NOTE When more than one signal is transmitted through the same interface, the sampling frequencies are
identical.
3.2
audio sample word
value of a digital audio sample. Representation is linear in 2s complement binary form
NOTE Positive numbers correspond to positive analogue voltages at the input of the Analogue-to-Digital Converter
(ADC).
– 6 – 60958-1  IEC:2004
3.3
auxiliary sample bit
one of the four least significant bits (LSBs) that can be assigned as auxiliary sample bits and
used for auxiliary information when the number of audio sample bits in the main data field is
less than or equal to 20
3.4
validity bit
bit indicating whether the main data field bits in the sub-frame (time slots 4 to 27 or 8 to 27,
depending on the audio word length as described in 4.1.1) are reliable or not
3.5
channel status
carrier, in a fixed format, of information associated with each main data field channel which is
decodable by any interface user
NOTE Examples of information to be carried in the channel status are: length of audio sample words, pre-
emphasis, sampling frequency, time codes, alphanumeric source and destination codes.
3.6
user data
data channel provided to carry any other information
3.7
parity bit
bit provided to permit the detection of an odd number of errors resulting from malfunctions in
the interface
3.8
preamble
specific patterns used for synchronization
NOTE There are three different preambles (see 4.3).
3.9
sub-frame
fixed structure used to carry information (see 4.1.1 and 4.1.2)
3.10
frame
sequence of two successive and associated sub-frames
3.11
block
group of 192 consecutive frames
NOTE The start of a block is designated by a special sub-frame preamble (see 4.3).
3.12
channel coding
coding method by which the binary digits are represented for transmission through the interface
3.13
unit interval
UI
shortest nominal time interval in the coding scheme
NOTE There are 128 UI in a sample frame.

60958-1  IEC:2004 – 7 –
3.14
interface jitter
deviation in the timing of interface data transitions (zero crossings) when compared with an
ideal clock
3.15
intrinsic jitter
output interface jitter of a device that is either free-running or is synchronized to a jitter-free
reference
3.16
jitter gain
ratio of the amplitude of jitter components at the output, to their amplitude at the
synchronization input to the device under test
4 Interface format
4.1 Structure of format
4.1.1 Sub-frame format
Each sub-frame is divided into 32 time slots, numbered from 0 to 31 (see Figure 1).
Time slots 0 to 3 (preambles) carry one of the three permitted preambles (see 4.1.2 and 4.3;
see also Figure 2).
Time slots 4 to 27 (main data field) carry the audio sample word in linear 2's complement
representation. The most significant bit (MSB) is carried by time slot 27.
When a 24-bit coding range is used, the LSB is in time slot 4 (see Figure 1).
When a 20-bit coding range is used, time slots 8 to 27 carry the audio sample word with
the LSB in time slot 8. Time slots 4 to 7 may be used for other applications. Under
these circumstances, the bits in the time slots 4 to 7 are designated auxiliary sample bits (see
Figure 1).
If the source provides fewer bits than the interface allows (either 20 or 24), the unused LSBs
are set to a logical "0".
For a non-linear PCM audio application or a data application, the main data field may carry any
other information.
Time slot 28 (validity bit) carries the validity bit associated with the main data field (see 4.4).
Time slot 29 (user data bit) carries 1 bit of the user data channel associated with the main data
field channel transmitted in the same sub-frame.
NOTE 1 For the applications, refer to the other parts of the IEC 60958 series.
Time slot 30 (channel status bit) carries 1 bit of the channel status information associated with
the main data field channel transmitted in the same sub-frame.
NOTE 2 For details refer to the other parts of the IEC 60958 series.
Time slot 31 (parity bit) carries a parity bit such that time slots 4 to 31 inclusive carry an even
number of ones and an even number of zeros (even parity).
NOTE 3 The preambles have even parity as an explicit property.

– 8 – 60958-1  IEC:2004
0 3 4 7 8 27 28 31
L
Sync M
Aux Audio sample word V U C P
S
preamble S
B
B
Validity flag
User data
Channel status
Parity bit
IEC  1756/99
Figure 1 – Sub-frame format (linear PCM application)
4.1.2 Frame format
A frame is uniquely composed of two sub-frames (see Figure 2). For linear coded audio
applications, the rate of transmission of frames normally corresponds exactly to the source
sampling frequency.
In 2-channel operation mode, the samples taken from both channels are transmitted by time
multiplexing in consecutive sub-frames. The first sub-frame (left or "A" channel in stereophonic
operation and primary channel in monophonic operation) normally starts with preamble "M".
However, the preamble changes to preamble "B" once every 192 frames to identify the start of
the block structure used to organize the channel status information. The second sub-frame
(right or "B" channel in stereophonic operation and secondary channel in monophonic
operation) always starts with preamble "W".
In single channel operation mode in a professional application, the frame format is the same as
in the 2-channel mode. Data is carried in the first sub-frame and may be duplicated in the
second sub-frame. If the second sub-frame is not carrying duplicate data, time slot 28 (validity
flag) shall be set to logical "1".
NOTE For historical reasons, preambles "B", "M" and "W" are, for use in professional applications, referred to as
"Z", "X" and "Y", respectively.
X Y Z Y X Y X
M Channel 1 W Channel 2 B Channel 1 W Channel 2 M Channel 1 W Channel 2 M
Sub-frame Sub-frame
Frame 191 Frame 0 Frame 1
Start of block
IEC  1757/99
Figure 2 – Frame format
4.2 Channel coding
To minimize the direct current (DC) component on the transmission line, to facilitate clock
recovery from the data stream and to make the interface insensitive to the polarity of
connections, time slots 4 to 31 are encoded in biphase-mark.
Each bit to be transmitted is represented by a symbol comprising two consecutive binary states.
The first state of a symbol is always different from the second state of the previous symbol.
The second state of the symbol is identical to the first if the bit to be transmitted is logical "0".
However, it is different if the bit is logical "1" (see Figure 3).

60958-1  IEC:2004 – 9 –
Clock (twice bit rate)
Source coding
Channel coding (biphase mark)
IEC  1758/99
Figure 3 – Channel coding
4.3 Preambles
Preambles are specific patterns providing synchronization and identification of the sub-frames
and blocks.
To achieve synchronization within one sampling period and to make this process completely
reliable, these patterns violate the biphase-mark code rules, thereby avoiding the possibility of
data imitating the preambles.
A set of three preambles is used. These preambles are transmitted in the time allocated to four
time slots at the start of each sub-frame (time slots 0 to 3), and are represented by eight
successive states. The first state of the preamble is always different from the second state of
the previous symbol (representing the parity bit). Depending on this state, the preambles are as
shown in Table 1.
Table 1 – Preamble coding
Preceding state 0 1
Preamble code Channel coding
“B” or “Z” 11101000 00010111 Sub-frame 1 and
(see note to 4.1.2) the start of the block
“M” or “X” 11100010 00011101 Sub-frame 1
“W” or “Y” 11100100 00011011 Sub-frame 2

Like biphase code, these preambles are d.c. free and provide clock recovery. They differ in at
least two states from any valid biphase sequence.
Figure 4 represents preamble "M".
NOTE Owing to the even-parity bit in time slot 31, all preambles start with a transition in the same direction
(see 4.1.1). Thus, only one of these sets of preambles is, in practice, transmitted through the interface. However, it
is necessary for both sets to be decodable because either polarity is possible in a connection.

– 10 – 60958-1  IEC:2004
Clock
Parity LSB
Lack of transition at bit boundary

IEC  1759/99
Figure 4 – Preamble M (shown as 11100010)
4.4 Validity bit
The validity bit is logical "0" if the information in the main data field is reliable, and it is logical
"1" if it is not. There is no default state for the validity bit.
NOTE For transmissions not using a linear PCM coding, this bit may be set. This is intended to prevent accidental
decoding of non-audio data to analogue before a complete channel status block is received. See Annex A.
5 Channel status
5.1 General
For every sub-frame, the channel status provides information related to the data carried in the
main data field of that same sub-frame.
Channel status information is organized in a 192-bit block, subdivided into 24 bytes. The first
bit of each block is carried in the frame with preamble "B”. The channel status data format is
defined in Table 2.
The specific organization depends on the application. In the descriptions, the suffix "0"
designates the first byte or bit. Where channel status bits are combined to form non-binary
values, the least significant bit should be transmitted first, unless otherwise indicated.
5.2 Applications
The primary application is indicated by the first channel status bit (bit 0) of a block as defined
in 5.3.
For professional applications, refer to IEC 60958-4.
For consumer applications, refer to IEC 60958-3.
Secondary applications may be defined within the framework of these primary applications.
Application documents or specifications are listed in Annex B.

60958-1  IEC:2004 – 11 –
5.3 General assignment of the first and second channel status bits
The first and second channel status bits (bit 0 and bit 1) are specified as follows.
Byte 0
Bit 0 “0” Consumer use of channel status block.
“1” Professional use of channel status block.

Bit 1 “0” Main data field represents linear PCM samples.
“1” Main data field used for purposes other purposes.
5.4 Category code
Channel status including the category code is defined in IEC 60958-3 for consumer
applications; these category codes are used for other variations of the IEC 60958 series for
consumer use, such as the IEC 61937 series.
Channel status is also defined in IEC 60958-4 for professional applications, and these data are
used for other variations of the IEC 60958 series for professional use, such as SMPTE 337M.

– 12 – 60958-1  IEC:2004
Table 2 – Channel status data format

Byte
0 a b
bit 0 1 2 3 4 5 6 7
bit 8 9 10 11 12 13 14 15
bit 16 17 18 19 20 21 22 23
bit 24 25 26 27 28 29 30 31
bit 32 33 34 35 36 37 38 39
bit 40 41 42 43 44 45 46 47
bit 48 49 50 51 52 53 54 55
bit 56 57 58 59 60 61 62 63
bit 64 65 66 67 68 69 70 71
bit 72 73 74 75 76 77 78 79
bit 80 81 82 83 84 85 86 87
bit 88 89 90 91 92 93 94 95
bit 96 97 98 99 100 101 102 103
bit 104 105 106 107 108 109 110 111
bit 112 113 114 115 116 117 118 119
bit 120 121 122 123 124 125 126 127

bit 128 129 130 131 132 133 134 135

bit 136 137 138 139 140 141 142 143

bit 144 145 146 147 148 149 150 151

bit 152 153 154 155 156 157 158 159

bit 160 161 162 163 164 165 166 167
bit 168 169 170 171 172 173 174 175
bit 176 177 178 179 180 181 182 183
bit 184 185 186 187 188 189 190 191
a: use of channel status block.
b: linear PCM identification.
60958-1  IEC:2004 – 13 –
6 User data
6.1 General
The default value of the user bits is logical "0".
6.2 Applications
6.2.1 Professional use
User data may be used in any way required by the user. Application details are described in
IEC 60958-4.
6.2.2 Consumer use
The application of the user data in digital audio equipment for consumer use is in accordance
with IEC 60958-3.
7 Electrical requirements
The type of transmission line and timing accuracy of the transmitted signal waveform shall be
as defined in other parts of IEC 60958-3 and IEC 60958-4, to meet the specifically required
quality or purpose of use.
– 14 – 60958-1  IEC:2004
Annex A
(informative)
The use of the validity bit
The IEC 60958 series is based on two different industry standards: the AES/EBU digital audio
interface standard (AES3 and EBU Tech. 3250-E) and the digital interface specification by
Sony and Philips (SPDIF) introduced with the Compact Disc Digital Audio system.
Unfortunately, significant differences between the two standards exist, which can contribute in
part to the different application areas: professional and consumer. The differences have
contributed to many misunderstandings about the use and compatibility of the standards.
Originally, the definition of validity was, in both industry standards, that it indicated whether or
not the associated audio sample was "secure and error free". Although, at first glance this may
seem a clear definition, in practice it has led to important practical problems. It is unclear how
the receiver should interpret this. When the sample is signalled not to be in error, it is not clear
whether the transmitter has performed a successful concealment. If a sample is signalled in
error, it is not clear whether the sample should be passed on unchanged, concealed or muted.
As a result, the AES has adopted in the 1992 revision of the AES3 standard a different
wording: Validity indicates "whether the audio sample bits are suitable for conversion to an
analogue audio signal".
Over the years, the application of the IEC 60958 series has gained popularity, resulting in a
growing number of products conforming to its provisions. With these in use, applications other
than strictly linear PCM audio transmission started to appear as well. The same basic frame
structure is used, but the information transferred in the "audio sample word" is not encoded as
linear PCM audio. As it is not always clearly indicated what kind of signal is carried, connection
of such a transmitter to a linear PCM receiver may result in a very loud and noisy audio signal.
Therefore, it has been proposed in the revision of the IEC 60958 series to also adopt the
wording of the AES3 standard for the validity bit definition. However, especially in consumer
applications, the transmitter often has no active control of the validity bit. In many cases, this is
generated by the error correction circuitry and automatically copied in the IEC 60958 series
bitstream. A change of definition would, in theory, necessitate a redesign of circuits which have
been in use for many years.
For this reason, the definition of the validity bit remains basically unchanged in the IEC 60958
series. However, it is noted that for applications not using a linear PCM coding, the bit may be
set to "1", in which case it can prevent accidental decoding of non-audio data to analogue
before a complete channel status block is received. For future applications of the IEC 60958
series with non-linear PCM data, such a provision is highly recommended.
Additionally, in IEC 60958-4, it is specified that the validity bit shall be used to indicate whether
the audio sample is "suitable for conversion to an analogue audio signal using linear PCM
coding". This retains, for professional applications, the intention of the wording in the AES3
standard.
Although not a perfect solution to problems relating to the use of the validity bit, the definitions
as adopted in the IEC 60958 series seem to be the best achievable compromise to date.
The use described in this annex should be applied to all other IEC 60958 data conformant
formats. This applies, for example, to the IEC 60958 series conformant mode of IEC 61883-6.

60958-1  IEC:2004 – 15 –
Annex B
(informative)
Application documents and specifications

Table B.1 indicates application documents and specification based on channel status bit 0 and
bit 1, as defined in 5.3.
Table B.1 – Application documents and specifications
Byte0 of
Channel status Standards
Bit0 Bit1
0 0 IEC 60958-3
1 0 IEC 60958-4
0 1 IEC 61937, IEC 62105 and others
1 1 SMPTE 337M and others
For that part of the channel status that is not implemented, the default is logical “0”.

– 16 – 60958-1  IEC:2004
Annex C
(informative)
A relationship of the IEC 60958 series families

A relationship between IEC specifications that are based on the IEC 60958 series is illustrated
in Figure C.1.
IIEECC 60958 60958--11 IEC-PIEACS 61883- 61883-66
Digital audio interface: General A/M Protocol
Digital audio interface: A/M Protocol
G l
IEC 60958 series conformant
LiLinearnear P PCCMM A Audiudioo
IIEECC 60958 60958--33
Consumer applications
Consumer Applications
IIEECC 61937 61937--33
IIEECC 60958 60958--44
ACAC--33
PPrrofofesesssiionalonal A applppliiccaattiionsons
IIEECC 61937 61937--44
MMPEGPEG--1,1, --2 A2 audiudioo
NoNnon--LinearLinear PC PMC AMudi audio o
IIEECC 61937 61937--11 IIEECC 61937 61937--55
GGenereneralal DTDTSS
IIEECC 61937 61937--22 IIEECC 61937 61937--66
BBuursrstt--iinfnfoo MMPEGPEG2-2 AAC AAC
IEC 61937-7
IEC 61937-7
AATTRRAACC and A and ATTRRAACC2/2/33
DaDattaa
IIEECC 62105/62105 /E ENN 50255 50255
RDIRDI
Figure C.1 – A relationship of the IEC 60958 series families
As illustrated, the IEC 60958 series consists of parts and also forms the basis for other
applications. The IEC 61937 series and IEC 62105 are protocols that use the format of
IEC 60958 as a transport, and the IEC 60958 series conformant mode in IEC 61883-6 is a
variant where the data in an IEC 60958 stream is carried on the physical format of IEC 61883-6.
This means that the IEC 60958 series – with data formats transported on the IEC 60958 series
– can itself be carried on another interface format. As a result, the IEC 60958 series has
relevance across various interface formats and systems.

60958-1  IEC:2004 – 17 –
Annex D
(informative)
Transmission of CD data other than linear PCM audio

This standard allows the interface to carry data related to computer software or signals coded
using non-linear PCM and the format specification for these applications is not part of this
standard. The channel status Bit 1 of Byte 0 indicates whether the data is linear PCM or not.
However, some CD applications currently set this Bit 1=”0” as meaning linear PCM data, while
the actual data is not linear PCM but compressed audio data. Such applications do not conform
to the IEC 60958 series.
Current data processing equipment such as computers and games machines have a CD-ROM
drive and sometimes a IEC 60958 series interface, so there is a possibility of non-linear PCM
data output that is dependent on the application software.
Therefore, all equipment and applications should respect the channel status definitions in this
standard to prevent unexpected behaviour in the decoder.
Consideration is required for applications that, for historic reasons, do not behave in
accordance with IEC 60958 with respect to channel status bit 1. This is in order to avoid a high
level of noise being generated by the conversion of this signal as though is was linear PCM
data. Such noise might damage hearing or equipment.

– 18 – 60958-1  IEC:2004
Bibliography
SMPTE 337M-2000, Television – Format for Non-PCM Audio and Data in an AES3 Serial
Digital Audio Interface
IEC 61883-6:2002, Consumer audio/video equipment – Digital interface – Part 6: Audio and
music data transmission protocol
IEC 61937 (all parts), Digital audio – Interface for non-linear PCM encoded audio bitstreams
applying IEC 60958
IEC 62105:1999, Digital audio broadcast system – Specification of the receiver data interface
(RDI)
___________
– 20 – 60958-1  CEI:2004
SOMMAIRE
AVANT-PROPOS . 21

1 Domaine d’application . 23
2 Références normatives . 23
3 Termes et définitions . 23
4 Format d’interface . 25
4.1 Structure du format . 25
4.2 Codage de la voie . 27
4.3 Préambules . 27
4.4 Bit de validité . 28
5 Voie de signalisation . 29
5.1 Généralités . 29
5.2 Applications . 29
5.3 Assignation générale des premier et second bits de la voie de signalisation . 29
5.4 Code de catégorie . 29
6 Données utilisateur . 31
6.1 Généralités . 31
6.2 Applications . 31
7 Exigences électriques . 31

Annexe A (informative) Utilisation du bit de validité . 32
Annexe B (informative) Documents et spécifications d'application . 34
Annexe C (informative) Relation entre les familles de la série CEI 60958 . 35
Annexe D (informative) Transmission de données de CD autres que des données
audio codées par codage MIC linéaire . 37

Bibliographie . 38

Tableau 1 – Codage du préambule . 28
Tableau 2 – Format des données de la voie de signalisation . 30
Tableau B.1 – Documents et spécifications d'application . 34

60958-1  CEI:2004 – 21 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
INTERFACE AUDIONUMÉRIQUE –
Partie 1: Généralités
AVANT-PROPOS
1) La Commission Electrotechnique Internationale (CEI) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a
pour objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les
domaines de l'électricité et de l'électronique. A cet effet, la CEI – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
public (PAS) et des Guides (ci-après dénommés "Publication(s) de la CEI"). Leur élaboration est confiée à des
comités d'études, aux travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les
organisations internationales, gouvernementales et non gouvernementales, en liaison avec la CEI, participent
également aux travaux. La CEI collabore étroitement avec l'Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de la CEI concernant les questions techniques représentent, dans la mesure
du possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de la CEI
intéressés sont représentés dans chaque comité d’études.
3) Les Publications de la CEI se présentent sous la forme de recommandations internationales et sont agréées
comme telles par les Comités nationaux de la CEI. Tous les efforts raisonnables sont entrepris afin que la CEI
s'assure de l'exactitude du contenu technique de ses publications; la CEI ne peut pas être tenue responsable
de l'éventuelle mauvaise utilisation ou interprétation qui en est faite par un quelconque utilisateur final.
4) Dans le but d'encourager l'uniformité internationale, les Comités nationaux de la CEI s'engagent, dans toute la
mesure possible, à appliquer de façon transparente les Publications de la CEI dans leurs publications
nationales et régionales. Toutes divergences entre toutes Publications de la CEI et toutes publications
nationales ou régionales correspondantes doivent être indiquées en termes clairs dans ces dernières.
5) La CEI elle-même ne fournit aucune attestation de conformité. Des organismes de certification indépendants
fournissent des services d'évaluation de conformité et, dans certains secteurs, accèdent aux marques de
conformité de la CEI. La CEI n'est responsable d'aucun des services effectués par les organismes de
certification indépendants.
6) Tous les utilisateurs doivent s'assurer qu'ils sont en possession de la dernière édition de cette publication.
7) Aucune responsabilité ne doit être imputée à la CEI, à ses administrateurs, employés, auxiliaires ou
mandataires, y compris ses experts particuliers et les membres de ses comités d'études et des Comités
nationaux de la CEI, pour tout préjudice causé en cas de dommages corporels et matériels, ou de tout autre
dommage de quelque nature que ce soit, directe ou indirecte, ou pour supporter les coûts (y compris les frais
de justice) et les dépenses découlant de la publication ou de l'utilisation de cette Publication de la CEI ou de
toute autre Publication de la CEI, ou au crédit qui lui est accordé.
8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L’attention est attirée sur le fait que certains des éléments de la présente Publication de la CEI peuvent faire
l’objet de droits de brevet. La CEI ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits
de brevets et de ne pas avoir signalé leur existence.
La CEI 60958-1, deuxième édition, a été établie par le domaine technique 4: Interfaces de
systèmes numériques, du comité d'études 100 de la CEI: Systèmes et appareils audio, vidéo
et multimédia.
Cette deuxième édition de la CEI 60958-1 annule et remplace la première édition publiée en
1999 et constitue une révision technique.
Toutes les modifications introduites dans cette seconde édition de la CEI 60958-1 sont
destinées à clarifier la structure et la relation entre toutes les familles de la série CEI 60958.
Une brève liste des modifications comporte ce qui suit.
• Une Annexe B a été ajoutée pour expliquer la définition donnée en 5.3 en relation avec
les familles de la série CEI 60958. Un paragraphe 5.3 a également été ajouté à cette
description.
– 22 – 60958-1  CEI:2004
• Une Annexe C a été ajoutée pour expliquer la relation entre les familles de la série
CEI 60958.
• Une Annexe D a été ajoutée à titre d'explication d'une t
...