php-modbus/tutorials/Phpmodbus/Phpmodbus.pkg

<refentry id="{@id}">
 <refnamediv>
  <refname>Phpmodbus user's guide</refname>
  <refpurpose>Phpmodbus How-to</refpurpose>
 </refnamediv>
 <refsynopsisdiv>
  <author>
   Jan Krakora
   <authorblurb>
    {@link mailto:krakora.jan@googlemail.com email}
   </authorblurb>
  </author>
 </refsynopsisdiv>
 {@toc}
 <refsect1 id="{@id intro}">
  <title>Introduction</title>
  <para>
   Phpmodbus is a PHP library for the Modbus protocol. The library implements
   Modbus TCP/UDP master class with subset of the most used Modbus commands.
  </para>
  <para>
   The library implements:
   <itemizedlist>
     <listitem><para>FC  1: read multiple coils</para></listitem>
     <listitem><para>FC  2: read input discretes</para></listitem>
     <listitem><para>FC  3: read multiple registers</para></listitem>
     <listitem><para>FC  6: write single register</para></listitem>
     <listitem><para>FC 15: write multiple coils</para></listitem>
     <listitem><para>FC 16: write multiple registers</para></listitem>
     <listitem><para>FC 23: read write registers</para></listitem>
    </itemizedlist>
  </para>
  <para>
   For more about Modbus protocol see [{@link http://www.modbus.org}] or
   [{@link http://en.wikipedia.org/wiki/Modbus Wiki}]
  </para>
 </refsect1>
 <refsect1 id="{@id install}">
  <title>Install</title>
  <para>
   At the first, it is supposed an PHP solution has been already installed on
   your server (LAMP, WAMP, MSS+CGI etc.).
  </para>
  <para>
   Copy the Phpmodbus library to your PHP project folder.
  </para>
  <para>
   Create a PHP script and assign the library using require_once() command
     <programlisting role="c">
      <![CDATA[require_once dirname(__FILE__) . '/Phpmodbus/ModbusMaster.php'; ]]>
     </programlisting>     
  </para>
  <para>
    To create UDP Modbus master object communicating to an modbus slave 
    e.g. at IP address 192.168.1.1 write
    <programlisting role="c" linenumbering="numbered" startinglinenumber="2">
      <![CDATA[ $modbus = new ModbusMaster("192.168.1.1", "UDP"); ]]>
    </programlisting>
  </para>
  <para>
    To create TCP Modbus master use
    <programlisting role="c" linenumbering="numbered" startinglinenumber="2">
      <![CDATA[ $modbus = new ModbusMaster("192.168.1.1", "TCP"); ]]>
    </programlisting>
  </para>
  <para>
    To read 5 words (10 bytes) from the device ID=0 and its memory address 12288
    use try-catch method call
    <programlisting role="c" linenumbering="numbered" startinglinenumber="3">
      <![CDATA[try {
    // Function processing
    $recData = $modbus->readMultipleRegisters(0, 12288, 5); 
}
catch (Exception $e) {
    // Exception processing, e.g. print error information
    echo $modbus;
    echo $e;
    exit; 
}]]>
     </programlisting>
  </para>
  <para>
    To process the function byte stream, use conversion to PHP types in 
  </para>
  <programlisting role="c" linenumbering="numbered" startinglinenumber="15">
      <![CDATA[echo PhpType::bytes2string($recData); ]]>
     </programlisting>
  <para>
  For other examples see sections bellow.
  </para>
 </refsect1>  
 <refsect1 id="{@id examples}">
  <title>Examples</title>
  <para>
    This section presents library features and examples
  </para>
    <refsect2 id="{@id example_fc1}">
    <title>FC1 - read mutliple coils</title>
    <para>
      FC1 functionality example
    </para>
    <para>
    {@example example_fc1.php}
    </para>
  </refsect2>
  <refsect2 id="{@id example_fc2}">
    <title>FC2 - read input discretes</title>
    <para>
      FC2 functionality example
    </para>
    <para>
    {@example example_fc2.php}
    </para>
  </refsect2>
  <refsect2 id="{@id example_fc3}">
    <title>FC3 - read mutliple registers</title>
    <para>
      FC3 functionality example
    </para>
    <para>
    {@example example_fc3.php}
    </para>
  </refsect2>
  <refsect2 id="{@id example_fc6}">
    <title>FC6 - write single register</title>
    <para>
      FC6 functionality example
    </para>
    <para>
    {@example example_fc6.php}
    </para>
  </refsect2>
  <refsect2 id="{@id example_fc15}">
    <title>FC15 - write mutliple coils</title>
    <para>
      FC15 functionality example
    </para>
    <para>
    {@example example_fc15.php}
    </para>
  </refsect2>
  <refsect2 id="{@id example_fc16}">
    <title>FC16 - write mutliple registers</title>
    <para>
      FC16 functionality example
    </para>
    <para>
    {@example example_fc16.php}
    </para>
  </refsect2>
  <refsect2 id="{@id example_fc23}">
    <title>FC23 - read write registers</title>
    <para>
      FC23 functionality example
    </para>
    <para>
    {@example example_fc23.php}
    </para>
  </refsect2>
  <refsect2 id="{@id wago_example}">
    <title>Dump of M-memory from WAGO 750-84x series coupler.</title>
    <para>
      Dump of M-memory from WAGO 750-84x series coupler.
    </para>
    <para>
    {@example example_750841_Mmemory.php}
    </para>
  </refsect2>
  <refsect2 id="{@id datatype}">
    <title>Data conversion to PHP types.</title>
    <para>
      Conversion of the data bytes, received from Modbus, to a PHP type.
    </para>
    <para>
    {@example example_datatype.php}
    </para>
  </refsect2>
 </refsect1> 
 <refsect1 id="{@id back_comp}">
  <title>Back compatibility</title>
  <para>
   This version is back compatible to the last versions. Just use  
   <programlisting role="c">
      <![CDATA[require_once dirname(__FILE__) . '/Phpmodbus/ModbusMasterUdp.php';
$modbus = new ModbusMasterUdp("192.168.1.1"); 
// ... ]]>
     </programlisting>
  </para>
 </refsect1>
</refentry>