IEC 61162-1:2010

IEC 61162-1 ®
Edition 4.0 2010-11
INTERNATIONAL
STANDARD
colour
inside
Maritime navigation and radiocommunication equipment and systems – Digital
interfaces –
Part 1: Single talker and multiple listeners

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IEC 61162-1 ®
Edition 4.0 2010-11
INTERNATIONAL
STANDARD
colour
inside
Maritime navigation and radiocommunication equipment and systems – Digital
interfaces –
Part 1: Single talker and multiple listeners

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XG
ICS 47.020.70 ISBN 978-2-88912-256-1
– 2 – 61162-1 Ó IEC:2010(E)
CONTENTS
FOREW ORD . 7
INTRODUCTION . 9
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 11
4 Manufacturer's documentation . 11
5 Hardware specification . 11
5.1 General . 11
5.2 Interconnecting wire. 11
5.3 Conductor definitions . 11
5.4 Electrical connections/shield requirements . 12
5.5 Connector . 12
5.6 Electrical signal characteristics. 12
5.6.1 General. 12
5.6.2 Signal state definitions . 12
5.6.3 Talker drive circuits . 12
5.6.4 Listener receive circuits . 12
5.6.5 Electrical isolation . 13
5.6.6 Maximum voltage on bus . 13
6 Data transmission . 13
7 Data format protocol . 14
7.1 Characters . 14
7.1.1 General. 14
7.1.2 Reserved characters . 14
7.1.3 Valid characters . 14
7.1.4 Undefined characters . 14
7.1.5 Character symbols . 14
7.2 Fields . 14
7.2.1 String . 14
7.2.2 Address field . 15
7.2.3 Data fields . 15
7.2.4 Checksum field . 16
7.2.5 Sequential message identifier field . 17
7.3 Sentences . 17
7.3.1 General structure . 17
7.3.2 Description of approved sentences . 17
7.3.3 Parametric sentences . 18
7.3.4 Encapsulation sentences . 19
7.3.5 Query sentences . 21
7.3.6 Proprietary sentences . 21
7.3.7 Command sentences . 22
7.3.8 Valid sentences . 23
7.3.9 Multi-sentence messages . 23
7.3.10 Sentence transmission timing . 23
7.3.11 Additions to approved sentences . 23

61162-1 Ó IEC:2010(E) – 3 –
7.4 Error detection and handling. 24
7.5 Handling of deprecated sentences . 24
8 Data content . 24
8.1 Character definitions . 24
8.2 Field definitions . 27
8.3 Approved sentences . 29
8.3.1 General format . 29
8.3.2 AAM – Waypoint arrival alarm . 29
8.3.3 ABK – AIS addressed and binary broadcast acknowledgement . 29
8.3.4 ABM – AIS addressed binary and safety related message . 31
8.3.5 ACA – AIS channel assignment message . 31
8.3.6 ACK – Acknowledge alarm . 33
8.3.7 ACS – AIS channel management information source . 33
8.3.8 AIR – AIS interrogation request . 33
8.3.9 AKD – Acknowledge detail alarm condition . 35
8.3.10 ALA – Report detailed alarm condition . 35
8.3.11 ALR – Set alarm state . 36
8.3.12 APB – Heading/track controller (autopilot) sentence B . 37
8.3.13 BBM – AIS broadcast binary message . 37
8.3.14 BEC – Bearing and distance to waypoint – Dead reckoning . 38
8.3.15 BOD – Bearing origin to destination . 39
8.3.16 BWC – Bearing and distance to waypoint – Great circle . 39
8.3.17 BWR – Bearing and distance to waypoint – Rhumb line . 39
8.3.18 BWW – Bearing waypoint to waypoint . 40
8.3.19 CBR – Configure broadcast rates for AIS AtoN station message
command . 40
8.3.20 CUR – Water current layer – Multi-layer water current data . 41
8.3.21 DBT – Depth below transducer . 41
8.3.22 DDC – Display dimming control . 42
8.3.23 DOR – Door status detection . 42
8.3.24 DPT – Depth . 44
8.3.25 DSC – Digital selective calling information . 44
8.3.26 DSE – Expanded digital selective calling . 45
8.3.27 DTM – Datum reference . 45
8.3.28 ETL – Engine telegraph operation status . 46
8.3.29 EVE – General event message . 47
8.3.30 FIR – Fire detection . 47
8.3.31 FSI – Frequency set information . 49
8.3.32 GBS – GNSS satellite fault detection . 49
8.3.33 GEN – Generic binary information . 51
8.3.34 GFA – GNSS fix accuracy and integrity . 52
8.3.35 GGA – Global positioning system (GPS) fix data . 53
8.3.36 GLL – Geographic position – Latitude/longitude . 53
8.3.37 GNS – GNSS fix data . 54
8.3.38 GRS – GNSS range residuals . 55
8.3.39 GSA – GNSS DOP and active satellites . 57
8.3.40 GST – GNSS pseudorange noise statistics . 59
8.3.41 GSV – GNSS satellites in view . 60

– 4 – 61162-1 Ó IEC:2010(E)
8.3.42 HBT – Heartbeat supervision sentence . 61
8.3.43 HDG – Heading, deviation and variation . 62
8.3.44 HDT – Heading true . 62
8.3.45 HMR – Heading monitor receive . 63
8.3.46 HMS – Heading monitor set . 63
8.3.47 HSC – Heading steering command . 64
8.3.48 HSS – Hull stress surveillance systems . 64
8.3.49 HTC – Heading/track control command; HTD – Heading /track
control data . 64
8.3.50 LR1 – AIS long-range reply sentence 1 . 66
8.3.51 LR2 – AIS long-range reply sentence 2 . 66
8.3.52 LR3 – AIS long-range reply sentence 3 . 67
8.3.53 LRF – AIS long-range function . 67
8.3.54 LRI – AIS long-range interrogation . 68
8.3.55 MEB – Message input for broadcast command . 69
8.3.56 MSK – MSK receiver interface . 71
8.3.57 MSS – MSK receiver signal status . 71
8.3.58 MTW – Water temperature . 71
8.3.59 MWD – Wind direction and speed . 71
8.3.60 MWV – Wind speed and angle . 72
8.3.61 NAK – Negative acknowledgement . 72
8.3.62 NRM – NAVTEX receiver mask . 73
8.3.63 NRX – NAVTEX received message . 74
8.3.64 OSD – Own ship data . 75
8.3.65 POS – Device position and ship dimensions report or configuration
command . 76
8.3.66 PRC – Propulsion remote control status . 77
8.3.67 RMA – Recommended minimum specific LORAN-C data . 78
8.3.68 RMB – Recommended minimum navigation information . 79
8.3.69 RMC – Recommended minimum specific GNSS data . 79
8.3.70 ROR – Rudder order status . 81
8.3.71 ROT – Rate of turn . 81
8.3.72 RPM – Revolutions . 81
8.3.73 RSA – Rudder sensor angle . 81
8.3.74 RSD – Radar system data . 82
8.3.75 RTE – Routes . 82
8.3.76 SFI – Scanning frequency information . 83
8.3.77 SSD – AIS ship static data . 83
8.3.78 STN – Multiple data ID . 85
8.3.79 THS – True heading and status . 85
8.3.80 TLB – Target label . 85
8.3.81 TLL – Target latitude and longitude . 86
8.3.82 TRC – Thruster control data . 86
8.3.83 TRD – Thruster response data . 87
8.3.84 TTD – Tracked target data . 87
8.3.85 TTM – Tracked target message . 90
8.3.86 TUT – Transmission of multi-language text . 90
8.3.87 TXT – Text transmission . 92
8.3.88 UID – User identification code transmission . 92

61162-1 Ó IEC:2010(E) – 5 –
8.3.89 VBW – Dual ground/water speed. 93
8.3.90 VDM – AIS VHF data-link message . 93
8.3.91 VDO – AIS VHF data-link own-vessel report . 94
8.3.92 VDR – Set and drift. 94
8.3.93 VER – Version . 95
8.3.94 VHW – Water speed and heading . 96
8.3.95 VLW – Dual ground/water distance . 96
8.3.96 VPW – Speed measured parallel to wind . 96
8.3.97 VSD – AIS voyage static data . 96
8.3.98 VTG – Course over ground and ground speed . 98
8.3.99 WAT – Water level detection . 98
8.3.100 WCV – Waypoint closure velocity . 99
8.3.101 WNC – Distance waypoint to waypoint . 99
8.3.102 WPL – Waypoint location . 99
8.3.103 XDR – Transducer measurements . 100
8.3.104 XTE – Cross-track error, measured . 101
8.3.105 XTR – Cross-track error, dead reckoning . 101
8.3.106 ZDA – Time and date . 101
8.3.107 ZDL – Time and distance to variable point . 102
8.3.108 ZFO – UTC and time from origin waypoint . 102
8.3.109 ZTG – UTC and time to destination waypoint . 102
9 Applications . 102
9.1 Example parametric sentences . 102
9.1.1 General. 102
9.1.2 Example 1 – LORAN-C latitude/longitude . 102
9.1.3 Example 2 – LORAN-C arrival alarm . 103
9.1.4 Example 3 – Proprietary sentence . 103
9.1.5 Example 4 – RMA examples . 104
9.1.6 Example 5 – FSI examples . 104
9.1.7 Example 6 – MSK/MSS examples . 105
9.1.8 Example 7 – DSC and DSE sentences . 105
9.1.9 Example 8 – FIR, DOR and WAT sentences . 106
9.2 Example encapsulation sentences . 106
9.3 Examples of receiver diagrams. 106
Annex A (informative) Glossary . 108
Annex B (normative) Guidelines for methods of testing and required test results . 116
Annex C (normative) Six-bit binary field conversion . 122
Annex D (normative) Alarm system fields . 125
Annex E (informative) Example of use of FIR, DOR and WAT sentences . 135
Annex F (informative) Example encapsulation sentence . 139
Bibliography . 145

– 6 – 61162-1 Ó IEC:2010(E)
Figure 1 – Listener receive circuit . 13
Figure 2 – Data transmission format . 14
Figure 3 – Example 1, J-FET, N channel, opto-isolator based listener circuit . 106
Figure 4 – Example 2, NPN opto-isolator based listener circuit. 107
Figure C.1 – 6-bit binary code converted to valid IEC 61162-1 character . 123
Figure C.2 – Valid IEC 61162-1 character converted to 6-bit binary code . 124
Figure E.1 – Example system diagram . 136
Figure F.1 – Message data format . 140
Figure F.2 – Work sheet for decoding and interpreting encapsulated string . 144

Table 1 – Reserved characters . 24
Table 2 – Valid characters . 25
Table 3 – Character symbol . 26
Table 4 – Talker identifier mnemonics . 27
Table 5 – Field type summary . 28
Table B.1 – Example – Data string GGA sent by the EUT to the test receiver
(listener) . 119
Table B.2 – Checksum . 120
Table B.3 – Example – Data string GGA received by the EUT . 120
Table B.4 – Example – Checksum . 121
Table B.5 – Break of data line. 121
Table C.1 – Six-bit binary field conversion table . 122
Table D.1 – System alarm fields . 125
Table F.1 – Example message from ITU-R M.1371 . 143

61162-1 Ó IEC:2010(E) – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
MARITIME NAVIGATION AND RADIOCOMMUNICATION
EQUIPMENT AND SYSTEMS –
DIGITAL INTERFACES –
Part 1: Single talker and multiple listeners

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
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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
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interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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.
International Standard IEC 61162-1 has been prepared by IEC technical committee 80:
Maritime navigation and radiocommunication equipment and systems.
This fourth edition cancels and replaces the third edition published in 2007, and constitutes
a technical revision.
The main changes with respect to the previous edition are listed below:
· in Table 1 the “comment” block delimiter has been renamed “TAG” block delimiter,
· new identifiers have been added to Table 4,
· the following sentences have been removed from 8.3 as they are not used by other
standards prepared by technical committee 80: ALM and MLA which described almanac
data from satellite navigation systems, DCN which described DECCA data, DSI and DSR

– 8 – 61162-1  IEC:2010(E)
which controlled the DSC transponder, GLC and LCD which described LORAN data, and
GMP which supported land use of map projections,
 new sentences CBR, GFA, HBT, NAK, MEB, POS, TTD and VER have been added,
 corrections have been made to the following sentences: ABK, BBM, DOR, FIR, SSD, TUT,
and VTG,
 extra fields have been added to AIR to support further ITU messages,
 new fields have been added to GBS, GRS, GSA and GSV to support new satellite
navigation systems,
 a new navigational status indicator has been added to GNS and RMC,
 a new sentence status flag had been added to DDC, FSI, HSC and NRM,
 three additional tests have been added to Annex B.
The text of this standard is based on the following documents:
FDIS Report on voting
80/606/FDIS 80/609/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61162 series, published under the general title Maritime
navigation and radiocommunication equipment and systems – Digital interfaces, can be found
on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
The contents of the corrigendum of December 2013 have been included in this copy.

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 publication using a
colour printer.
61162-1 Ó IEC:2010(E) – 9 –
INTRODUCTION
International standard IEC 61162 is a four part standard which specifies four digital
interfaces for application in marine navigation, radiocommunication and system integration.
The four parts are:
IEC 61162-1 Single talker and multiple listeners;
IEC 61162-2 Single talker and multiple listeners, high speed transmission;
IEC 61162-3 Multiple talkers and multiple listeners – Serial data instrument network;
IEC 61162-4 Multiple talkers and multiple listeners – Ship systems interconnection.
IEC technical committee 80 interface standards are developed with input from
manufacturers, private and government organisations and equipment operators. The
information is intended to meet the needs of users at the time of publication, but users
should recognise that as applications and technology change, interface standards should
change as well. Users of this standard are advised to immediately inform the IEC of any
perceived inadequacies therein.
The first edition of IEC 61162-1 was published in 1995. The second edition published in
2000 removed some sentences which were no longer in use, added some new sentences
and included details of the ship equipment defined in IMO resolutions together with
appropriate sentences for communication between them. This information was subsequently
removed from the third edition when it became the practice to specify the sentence
formatters in the individual standards for equipment.
The third edition published in 2007 introduced a re-arrangement of the text and new
sentences particularly to support the Automatic Identification System and the Voyage Data
Recorder. The third edition also introduced a further type of start of sentence delimiter. The
conventional delimiter “$” was retained for the conventional sentences which are now called
parametric sentences. The new delimiter “!” identifies sentences that conform to special
purpose encapsulation.
This fourth edition removes some sentences which are not in use, adds some new
sentences for new applications and makes some corrections and additions. In particular the
sentences of relevance to satellite navigation receivers have been expanded to facilitate
the description of new satellite systems.
Liaison has been maintained with NMEA and this edition has been aligned where
appropriate with NMEA 0183 version 4.00.

– 10 – 61162-1 Ó IEC:2010(E)
MARITIME NAVIGATION AND RADIOCOMMUNICATION
EQUIPMENT AND SYSTEMS –
DIGITAL INTERFACES –
Part 1: Single talker and multiple listeners

1 Scope
This part of IEC 61162 contains the requirements for data communication between maritime
electronic instruments, navigation and radiocommunication equipment when interconnected
via an appropriate system.
This part of IEC 61162 is intended to support one-way serial data transmission from a single
talker to one or more listeners. This data is in printable ASCII form and may include
information such as position, speed, depth, frequency allocation, etc. Typical messages
may be from about 11 to a maximum of 79 characters in length and generally require
transmission no more rapidly than one message per second.
The electrical definitions in this standard are not intended to accommodate high-bandwidth
applications such as radar or video imagery, or intensive database or file transfer
applications. Since there is no provision for guaranteed delivery of messages and only
limited error checking capability, this standard should be used with caution in all safety
applications.
For applications where a faster transmission rate is necessary, reference should be made to
IEC 61162-2.
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 60945:2002, Maritime navigation and radiocommunication equipment and systems –
General requirements – Methods of testing and required test results
IEC 61162-2:1998, Maritime navigation and radiocommunication equipment and systems –
Digital interfaces – Part 2: Single talker and multiple listeners, high-speed transmission
ISO/IEC 8859-1:1998, Information technology – 8-bit single-byte coded graphic character
sets – Part 1: Latin alphabet No.1
ITU-T X.27/V.11:1996, Electrical characteristics for balanced double-current interchange
circuits operating at data signalling rates up to 10 Mbit/s

61162-1 Ó IEC:2010(E) – 11 –
3 Terms and definitions
Common terms are defined in the glossary of Annex A. Where there is a conflict, terms are
interpreted, wherever possible, in accordance with the references in Clause 2.
For the purposes of this document, the following terms and definitions apply.
3.1
talker
any device which sends data to other devices. The type of talker is identified by a 2-
character mnemonic as listed in 8.2 (see Table 4)
3.2
listener
any device which receives data from another device
4 Manufacturer's documentation
Operator manuals or other appropriate literature provided for equipment that is intended to
meet the requirements of this standard shall contain the following information:
a) identification of the A and B signal lines;
b) the output drive capability as a talker;
c) a list of approved sentences, noting unused fields, proprietary sentences transmitted as
a talker and transmission interval for each sentence;
d) the load requirements as a listener;
e) a list of sentences and associated data fields that are required as a listener;
f) the current software and hardware revision if this is relevant to the interface;
g) an electrical description or schematic of the listener/talker input/output circuits citing
actual components and devices used, including connector type and part number;
h) the version number and date of update of the standard for which compliance is sought.
5 Hardware specification
5.1 General
NOTE Guidelines on methods of testing are given in Annex B.
One talker and multiple listeners may be connected in parallel over an interconnecting wire.
The number of listeners depends on the output capability and input drive requirements of
individual devices.
5.2 Interconnecting wire
Interconnection between devices may be by means of a two-conductor, shielded, twisted-
pair wire.
5.3 Conductor definitions
The conductors referred to in this standard are the signal lines A and B, and shield.

– 12 – 61162-1 Ó IEC:2010(E)
5.4 Electrical connections/shield requirements
All signal line A connections are connected in parallel with all device A connections and all
signal line B connections are connected in parallel with all device B connections. The
shields of all listener cables should be connected to the talker chassis only and should not
be connected at each listener.
5.5 Connector
No standard connector is specified. Wherever possible readily available commercial
connectors shall be used. Manufacturers shall provide means for user identification of the
connections used.
5.6 Electrical signal characteristics
5.6.1 General
This subclause describes the electrical characteristics of transmitters and receivers.
5.6.2 Signal state definitions
The idle, marking, logical 1, OFF or stop bit states are defined by a negative voltage on line
A with respect to line B.
The active, spacing, logical 0, ON or start bit states are defined by a positive voltage on
line A with respect to line B.
It should be noted that the above A with respect to B levels are inverted from the voltage
input/output requirements of standard UARTs and that many line drivers and receivers
provide a logic inversion.
5.6.3 Talker drive circuits
No provision is made for more than a single talker to be connected to the bus. The drive
circuit used to provide the signal A and the return B shall meet, as a minimum, the
requirements of ITU-T X.27/V.11.
5.6.4 Listener receive circuits
Multiple listeners may be connected to a single talker. The listener receive circuit shall
consist of an opto-isolator and shall have protective circuits to limit current, reverse bias
and power dissipation at the opto-diode as shown in Figure 1. Reference is made to
example circuits in 9.2.
The receive circuit shall be designed for operation with a minimum differential input voltage
of 2,0 V and shall not take more than 2,0 mA from the line at that voltage.
___________
For reasons of compatibility with equipment designed to comply with earlier versions of NMEA 0183, it is noted
that the idle, marking, logical "1", OFF or stop bit state had previously been defined to be in the range –15,0 V to
+0,5 V. The active, spacing, logical "0", ON or start bit state was defined to be in the range +4,0 V to +15,0 V
while sourcing was not less than 15 mA.

61162-1 Ó IEC:2010(E) – 13 –
A
Protective
circuits
B
Opto-isolator
Listener No. 2
A A
Protective
circuits
B B
Opto-isolator
Shields
Listener No. 1
Talker
IEC  910/2000
Figure 1 – Listener receive circuit
5.6.5 Electrical isolation
Within a listener, there shall be no direct electrical connection between the signal line A,
return line B, or shield and ship’s ground or power. Isolation from ship’s ground is required.
5.6.6 Maximum voltage on bus
The maximum applied voltage between signal lines A and B and between either line and
ground shall be in accordance with ITU-T X.27/V.11.
For protection against mis-wiring and for use with earlier talker designs, all receive circuit
devices shall be capable of withstanding 15 V between signal lines A and B and between
either line and ground for an indefinite period.
6 Data transmission
Data is transmitted in serial asynchronous form in accordance with the standards referenced
in Clause 2. The first bit is a start bit and is followed by data bits, least-significant-bit first,
as illustrated by Figure 2.
The following parameters are used:
– baud rate 4 800;
– data bits 8 (D7 = 0), parity none;
– stop bits 1.
D0    D1   D2    D3    D4   D5   D6   D7

Data bits   Stop bit
Start bit
IEC  911/2000
– 14 – 61162-1 Ó IEC:2010(E)
Figure 2 – Data transmission format
7 Data format protocol
7.1 Characters
7.1.1 General
All transmitted data shall be interpreted as ASCII characters. The most significant bit of the
eight-bit character shall always be transmitted as zero (D7 = 0).
7.1.2 Reserved characters
The reserved character set consists of those ASCII characters shown in 8.1 (Table 1).
These characters are used for specific formatting purposes, such as sentence and field
delimiting, and except for code delimiting, shall not be used in data fields.
7.1.3 Valid characters
The valid character set consists of all printable ASCII characters (HEX 20 to HEX 7E)
except those defined as reserved characters. The list of the valid character set is given
in 8.1 (Table 2).
7.1.4 Undefined characters
ASCII values not specified as either “reserved characters” or “valid characters” are
excluded and shall not be transmitted at any time.
When it is necessary to communicate an 8-bit character defined by ISO/IEC 8859-1 that is a
reserved character (Table 1) or not listed in Table 2 as a valid character (e.g. in a
proprietary sentence or text sentence), three characters shall be used.
The reserved character “^“ (HEX 5E) is followed by two ASCII characters (0-9, A-F)
representing the HEX value of the character to be communicated. For example:
– to send heading as "127.5°", transmit “127.5 ^F8”;
– to send the reserved characters , transmit “^0D^0A”;
– to send the reserved character "^", transmit “^5E”.
IEC 60945 states that, as a minimum requirement, English language shall be used for
controls and displays. Other languages/characters are only supported by the TUT sentence.
7.1.5 Character symbols
When individual characters are used in this standard to define units of measurement, to
indicate the type of data field, type of sentence, etc. they shall be interpreted according
to the character symbol in 8.1 (Table 3).
7.2 Fields
7.2.1 String
A field consists of a string of valid characters, or no characters (null field), located between
two appropriate delimiter characters.

61162-1 Ó IEC:2010(E) – 15 –
7.2.2 Address field
7.2.2.1 General
An address field is the first field in a sentence and follows the "$" or “!” delimiter; it serves
to define the sentence. The "$" delimiter identifies sentences that conform to the
conventional parametric and delimited field composition rules as described in 7.3.3. The "!"
delimiter identifies sentences that conform to the special-purpose encapsulation and non-
delimited field composition rules as described in 7.3.3. Characters within the address field
are limited to digits and upper case letters. The address field shall not be a null field. Only
sentences with the following three types of address fields shall be transmitted.
7.2.2.2 Approved address field
Approved address fields consist of five digits and upper case letter characters defined by
this standard. The first two characters are the talker identifier, listed in 8.2 (Table 4). The
talker identifier serves to define the nature of the data being transmitted.
Devices that have the capabi
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