ais_msg_3.xml

<?xml version="1.0" encoding="utf-8"?>
<ais-binary-message version="1.0" xmlns:xi="http://www.w3.org/2001/XInclude">

  <xi:include href="structs-inc.xml"/>

  <!-- titlefield is what to use when a message needs to by titled (e.g. in kml) -->

  <!-- msg 1 does not have a dac, fid, or efid -->
  <message name="position" aismsgnum="3" titlefield="UserID">
    <description>Scheduled position report</description>
    <note>Need to make much of this an include-struct so that 1-3 are as simple as possible</note>
    <see-also></see-also>

    <!-- This next block of messages will get ignored... -->

    <messagesize>168</messagesize> <!-- number of bits in the message -->
    <category>F</category>
    <category>S</category>
    <priority>1</priority>
    <operationmode>AU</operationmode>
    <accessscheme>SOTDMA</accessscheme>
    <accessscheme>RATDMA</accessscheme>
    <accessscheme>ITDMA</accessscheme>
    <comstate>SOTDMA</comstate>
    <stationtype>mobile</stationtype>

    <!-- Back to tags that the compiler knows about -->

    <field name="MessageID" numberofbits="6" type="uint">
      <description>AIS message number.  Must be 1</description>
      <required>3</required>
    </field>

    <field name="RepeatIndicator" numberofbits="2" type="uint">
      <description>Indicated how many times a message has been repeated</description>
      <unavailable>0</unavailable>
      <lookuptable>
        <entry key="0">default</entry>
        <entry key="3">do not repeat any more</entry>
      </lookuptable>
      <testvalue>1</testvalue>
    </field>

    <field name="UserID" numberofbits="30" type="uint">
      <description>Unique ship identification number (MMSI)</description>
      <testvalue>1193046</testvalue> <!-- Default value for all NAUTICAST devices -->
    </field>

    <field name="NavigationStatus" numberofbits="4" type="uint">
      <description>What is the vessel doing</description>
      <unavailable>15</unavailable>
      <lookuptable>
        <entry key="0">under way using engine</entry>
        <entry key="1">at anchor</entry>
        <entry key="2">not under command</entry>
        <entry key="3">restricted maneuverability</entry>
        <entry key="4">constrained by her draught</entry>
        <entry key="5">moored</entry>
        <entry key="6">aground</entry>
        <entry key="7">engaged in fishing</entry>
        <entry key="8">under way sailing</entry>
        <entry key="9">reserved for future use (hazmat)</entry>
        <entry key="10">reserved for future use</entry>
        <entry key="11">reserved for future use</entry>
        <entry key="12">reserved for future use</entry>
        <entry key="13">reserved for future use</entry>
        <entry key="14">reserved for future use</entry>
        <entry key="15">not defined = default</entry>
      </lookuptable>
      <testvalue>3</testvalue>
    </field>

    <!-- FIX: this field is FUBAR/SNAFU -->
    <field name="ROT" numberofbits="8" type="int">
      <alias>RateOfTurn</alias>
      <description>Rate of turning.  Positive right; negative left.  BROKEN!</description>
      <note>This field is completely messed up due to the requirement to do a sqrt.  Need to fix this some day</note>
      <unavailable>-128</unavailable> <!-- FIX: kludge... this is really the raw value -->
      <units>4.733*sqrt(val) degrees/min</units>  <!-- FIX: doh! -->
      <testvalue>-2</testvalue>
      <!-- Arg... this is painful
           <encode>4.733*sqrt(value)</encode>
           <decode>(value/4.733)*(value/4.733)</decode>
           -->
    </field>

    <field name="SOG" numberofbits="10" type="udecimal">
      <description>Speed over ground</description>
      <unavailable>102.3</unavailable>
      <lookuptable>
        <entry key="102.2">102.2 knots or higher</entry>
      </lookuptable>
      <units>knots</units>
      <scale>10</scale>
      <decimalplaces>1</decimalplaces>
      <testvalue>101.9</testvalue>
    </field>


    <field name="PositionAccuracy" numberofbits="1" type="uint">
      <description>Accuracy of positioning fixes</description>
      <lookuptable>
        <entry key="0">low (greater than 10 m)</entry>
        <entry key="1">high (less than 10 m)</entry>
      </lookuptable>
      <testvalue>1</testvalue>
    </field>

    <include-struct name="Position" struct="position2d">
      <do_not_mangle_name/>
      <description>Location of the vessel</description>
    </include-struct>

    <field name="COG" numberofbits="12" type="udecimal">
      <description>Course over ground</description>
      <range min="0" max="359.9"/>
      <unavailable>360</unavailable>
      <units>degrees</units>
      <scale>10</scale>
      <decimalplaces>1</decimalplaces>
      <testvalue>34.5</testvalue>
    </field>

    <field name="TrueHeading" numberofbits="9" type="uint">
      <description>True heading (relative to true North)</description>
      <range min="0" max="359"/>
      <unavailable>511</unavailable>
      <units>degrees</units>
      <testvalue>41</testvalue>
    </field>

    <field name="TimeStamp" numberofbits="6" type="uint">
      <description>UTC second when the report was generated</description>
      <range min="0" max="59"/>
      <unavailable>60</unavailable>
      <lookuptable>
        <entry key="60">not available/default</entry>
        <entry key="61">manual input</entry>
        <entry key="62">dead reckoning</entry>
        <entry key="63">inoperative</entry>
      </lookuptable>
      <units>seconds</units>
      <testvalue>35</testvalue>
    </field>

    <!-- FIX: version 3 of ITU 1371 has this text for the regional reserved field
special
manoeuvre
indicator
2 0 = not available = default
1 = not engaged in special manoeuvre
2 = engaged in special manoeuvre
(i.e.: regional passing arrangement on Inland Waterway)

Spare then becomes 3 bits
-->

    <field name="RegionalReserved" numberofbits="4" type="uint">
      <description>Reserved for definition by a regional authority.</description>
      <required>0</required>
    </field>

    <field name="Spare" numberofbits="1" type="uint">
      <description>Not used.  Should be set to zero.</description>
      <required>0</required>
    </field>

    <field name="RAIM" numberofbits="1" type="bool">
      <description>Receiver autonomous integrity monitoring flag</description>
      <lookuptable>
        <entry key="False">not in use</entry>
        <entry key="True">in use</entry>
      </lookuptable>
      <testvalue>0</testvalue>
    </field>

    <!-- FIX: msg 3 needs to be itdma state -->
    <include-struct name="state" struct="sotdmaState">
      <description>Communications State - SOTDMA</description>
    </include-struct>


  </message> <!-- position -->

</ais-binary-message>