<?xml version="1.0" encoding="UTF-8"?>

<section xml:id="introDataServices" 
         xmlns="http://docbook.org/ns/docbook" 
         xmlns:xlink="http://www.w3.org/1999/xlink" 
         xmlns:xi="http://www.w3.org/2001/XInclude">

<info>
  <title>Data services</title>
</info>

<para>
  As DMR is a digital mode that transports digitalized speech, it is possible to transfer other
  data too. Consequently, there are some other digital services provided with DMR. First, there 
  are text messages similar to the one provided by mobile phones. It is also possible to forward 
  the own GPS position to the <glossterm>APRS</glossterm> network.
</para>


<section xml:id="introSMS">
<info><title>Textmessages (SMS)</title></info>

<para>
  With this service, you can transfer short text messages to other participants (like a private call) 
  or to a talk group (like a group call). The latter is rather uncommon and should be avoided. In 
  principle a text messages works like a private call. If the destination is reachable, the text 
  message will be routed to it.
</para>

<para> 
  There are also service numbers (free of charge). If messages are sent to them, certain 
  information can be retrieved to forwarded to other networks (e.g. to the 
  <glossterm>DAPNET</glossterm>). In Germany (and other countries) there are:
</para>

<orderedlist>
  <listitem>
    <para>262993 -- GPS and weather</para>
    <itemizedlist>
      <listitem><para>Send <token>help</token> and you will receive a list of commands.</para></listitem>
      <listitem><para>Send <token>wx</token> and you will receive the weather at the location of 
        the repeater you used.</para></listitem>
      <listitem><para>Send <token>wx CITY</token> and you will receive the weather at the specified
        city.</para></listitem>
      <listitem><para>Send <token>gps</token> and the last GPS position is returned that you have 
        sent to the DMR network.</para></listitem>
      <listitem><para>With <token>gps CALL</token> you can retrieve the last position sent by the 
        specified call.</para></listitem>
      <listitem><para>Send <token>rssi</token> and you will receive a signal report from the 
        repeater.</para></listitem>
    </itemizedlist>
  </listitem>
  <listitem>
    <para>262994 -- Repeater information &amp; pager messages</para>
    <itemizedlist>
      <listitem><para>Send <token>rpt</token> to receive a list of static an dynamic subscribed 
      talk groups at the repeater. </para></listitem>
      <listitem><para>Send <token>CALL MESSAGE</token> to send the given message to the given 
        destination call in the DAPNET. </para></listitem>
    </itemizedlist>
  </listitem>
</orderedlist>
</section>


<section xml:id="introAPRS">
<info><title>Position reporting to the APRS network</title></info>
<para>
  As mentioned in the previous section, it is possible to report the own position via the 
  DMR network to the APRS network. This position can then be tracked at for example 
  <link xlink:href="https://aprs.fi">aprs.fi</link>. To do that, a radio with a built-in 
  GPS receiver is required. But not even these devices are expensive anymore. Simple DMR 
  hand-helds with built-in GPS receivers are available for about 120€.
</para>
<para>
  Beside the text message services, it is also possible to transmit the position to the DMR 
  network using a special service number 262999. How the radio is configured to do that, 
  depends heavily on the device being used. <application>qdmr</application> helps with the 
  configuration by providing common means for these settings across all supported radios.
</para>
</section>

</section>