Add changes for bfc203c

_sources/creating_driver.rst.txt

@@ -2,14 +2,14 @@ Creating a **modbus** port driver
 ---------------------------------
 
 Before **modbus** port drivers can be created, it is necessary to first
-create at least one asyn TCP/IP or serial port driver to communicate
+create at least one asyn TCP/IP, UDP/IP or serial port driver to communicate
 with the hardware. The commands required depend on the communications
 link being used.
 
-TCP/IP
-~~~~~~
+TCP/IP UDP/IP
+~~~~~~~~~~~~~
 
-For TCP/IP use the following standard asyn command:
+For TCP/IP or UDP/IP use the following standard asyn command:
 
 ::
 
@@ -31,6 +31,7 @@ the asynInterpose interface does no harm.
 However, the asynInterposeEos interface is definitely needed when using drvAsynIPPortConfigure to talk 
 to a terminal server that is communicating with the Modbus device over Modbus RTU or ASCII, 
 because then the communication from the device may well be broken up into multiple packets.
+To use UDP rather than TCP, add " UDP" after the host name/number and optional port number.
 
 ::
 
@@ -105,7 +106,7 @@ modbusInterposeConfig
 After creating the asynIPPort or asynSerialPort driver, the next step is
 to add the asyn "interpose interface" driver. This driver takes the
 device-independent Modbus frames and adds or removes the
-communication-link specific information for the TCP, RTU, or ASCII link
+communication-link specific information for the TCP, UDP, RTU, or ASCII link
 protocols. The interpose driver is created with the command:
 
 ::
@@ -128,7 +129,7 @@ protocols. The interpose driver is created with the command:
     - Name of the asynIPPort or asynSerialPort previously created.
   * - linkType
     - int
-    - Modbus link layer type:, 0 = TCP/IP, 1 = RTU, 2 = ASCII
+    - Modbus link layer type:, 0 = TCP/IP, 1 = RTU, 2 = ASCII, 3 = UDP/IP
   * - timeoutMsec
     - int
     - The timeout in milliseconds for write and read operations to the underlying asynOctet
@@ -186,7 +187,7 @@ created with the following command:
   * - slaveAddress
     - int
     - The address of the Modbus slave. This must match the configuration of the Modbus
-      slave (PLC) for RTU and ASCII. For TCP the slave address is used for the "unit identifier",
+      slave (PLC) for RTU and ASCII. For TCP or UDP the slave address is used for the "unit identifier",
       the last field in the MBAP header. The "unit identifier" is ignored by most PLCs,
       but may be required by some.
   * - modbusFunction
@@ -454,4 +455,4 @@ Number formats
 It can be convenient to specify the modbusStartAddress and modbusLength
 in octal, rather than decimal, because this is the convention on most
 PLCs. In the iocsh and vxWorks shells this is done by using a leading 0
-on the number, i.e. 040400 is an octal number.
+on the number, i.e. 040400 is an octal number.

_sources/overview.rst.txt

@@ -21,6 +21,12 @@ Modbus supports the following 3 communication-link layers:
      - Description
    * - TCP
      - TCP/IP using standard port 502.
+   * - UDP
+     - UDP/IP using standard port 502. The use of UDP/IP is not part of the MODBUS
+     - standard but is useful for FPGAs with Ethernet in firmware which may provide
+     - support only for UDP.  The only difference between TCP and UDP operation is
+     - that when using UDP a missing reply packet is not considered to
+     - be an error until the transaction has been attempted 5 times.
    * - RTU
      - RTU is normally run over serial communication links, i.e. RS-232,
        RS-422, or RS-485. RTU uses an additional CRC for packet checking. The

acknowledgments.html

@@ -102,7 +102,7 @@ <h1>Acknowledgments<a class="headerlink" href="#acknowledgments" title="Link to
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

creating_driver.html

@@ -49,7 +49,7 @@
 <li class="toctree-l1"><a class="reference internal" href="overview.html">Overview of Modbus</a></li>
 <li class="toctree-l1"><a class="reference internal" href="driver_architecture.html">Driver architecture</a></li>
 <li class="toctree-l1 current"><a class="current reference internal" href="#">Creating a <strong>modbus</strong> port driver</a><ul>
-<li class="toctree-l2"><a class="reference internal" href="#tcp-ip">TCP/IP</a></li>
+<li class="toctree-l2"><a class="reference internal" href="#tcp-ip-udp-ip">TCP/IP UDP/IP</a></li>
 <li class="toctree-l2"><a class="reference internal" href="#serial-rtu">Serial RTU</a></li>
 <li class="toctree-l2"><a class="reference internal" href="#serial-ascii">Serial ASCII</a></li>
 <li class="toctree-l2"><a class="reference internal" href="#modbusinterposeconfig">modbusInterposeConfig</a></li>
@@ -93,12 +93,12 @@
   <section id="creating-a-modbus-port-driver">
 <h1>Creating a <strong>modbus</strong> port driver<a class="headerlink" href="#creating-a-modbus-port-driver" title="Link to this heading"></a></h1>
 <p>Before <strong>modbus</strong> port drivers can be created, it is necessary to first
-create at least one asyn TCP/IP or serial port driver to communicate
+create at least one asyn TCP/IP, UDP/IP or serial port driver to communicate
 with the hardware. The commands required depend on the communications
 link being used.</p>
-<section id="tcp-ip">
-<h2>TCP/IP<a class="headerlink" href="#tcp-ip" title="Link to this heading"></a></h2>
-<p>For TCP/IP use the following standard asyn command:</p>
+<section id="tcp-ip-udp-ip">
+<h2>TCP/IP UDP/IP<a class="headerlink" href="#tcp-ip-udp-ip" title="Link to this heading"></a></h2>
+<p>For TCP/IP or UDP/IP use the following standard asyn command:</p>
 <div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">drvAsynIPPortConfigure</span><span class="p">(</span><span class="n">portName</span><span class="p">,</span> <span class="n">hostInfo</span><span class="p">,</span> <span class="n">priority</span><span class="p">,</span> <span class="n">noAutoConnect</span><span class="p">,</span> <span class="n">noProcessEos</span><span class="p">)</span>
 </pre></div>
 </div>
@@ -116,7 +116,8 @@ <h2>TCP/IP<a class="headerlink" href="#tcp-ip" title="Link to this heading"><
 the asynInterpose interface does no harm.
 However, the asynInterposeEos interface is definitely needed when using drvAsynIPPortConfigure to talk
 to a terminal server that is communicating with the Modbus device over Modbus RTU or ASCII,
-because then the communication from the device may well be broken up into multiple packets.</p>
+because then the communication from the device may well be broken up into multiple packets.
+To use UDP rather than TCP, add “ UDP” after the host name/number and optional port number.</p>
 <div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">drvAsynIPPortConfigure</span><span class="p">(</span><span class="s2">&quot;Koyo1&quot;</span><span class="p">,</span><span class="s2">&quot;164.54.160.158:502&quot;</span><span class="p">,</span><span class="mi">0</span><span class="p">,</span><span class="mi">0</span><span class="p">,</span><span class="mi">0</span><span class="p">)</span>
 </pre></div>
 </div>
@@ -179,7 +180,7 @@ <h2>modbusInterposeConfig<a class="headerlink" href="#modbusinterposeconfig" tit
 <p>After creating the asynIPPort or asynSerialPort driver, the next step is
 to add the asyn “interpose interface” driver. This driver takes the
 device-independent Modbus frames and adds or removes the
-communication-link specific information for the TCP, RTU, or ASCII link
+communication-link specific information for the TCP, UDP, RTU, or ASCII link
 protocols. The interpose driver is created with the command:</p>
 <div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">modbusInterposeConfig</span><span class="p">(</span><span class="n">portName</span><span class="p">,</span>
                       <span class="n">linkType</span><span class="p">,</span>
@@ -201,7 +202,7 @@ <h2>modbusInterposeConfig<a class="headerlink" href="#modbusinterposeconfig" tit
 </tr>
 <tr class="row-odd"><td><p>linkType</p></td>
 <td><p>int</p></td>
-<td><p>Modbus link layer type:, 0 = TCP/IP, 1 = RTU, 2 = ASCII</p></td>
+<td><p>Modbus link layer type:, 0 = TCP/IP, 1 = RTU, 2 = ASCII, 3 = UDP/IP</p></td>
 </tr>
 <tr class="row-even"><td><p>timeoutMsec</p></td>
 <td><p>int</p></td>
@@ -261,7 +262,7 @@ <h2>drvModbusAsynConfigure<a class="headerlink" href="#drvmodbusasynconfigure" t
 <tr class="row-even"><td><p>slaveAddress</p></td>
 <td><p>int</p></td>
 <td><p>The address of the Modbus slave. This must match the configuration of the Modbus
-slave (PLC) for RTU and ASCII. For TCP the slave address is used for the “unit identifier”,
+slave (PLC) for RTU and ASCII. For TCP or UDP the slave address is used for the “unit identifier”,
 the last field in the MBAP header. The “unit identifier” is ignored by most PLCs,
 but may be required by some.</p></td>
 </tr>
@@ -581,7 +582,7 @@ <h2>Number formats<a class="headerlink" href="#number-formats" title="Link to th
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

debugging.html

@@ -222,7 +222,7 @@ <h2>asynRegister.adl<a class="headerlink" href="#asynregister-adl" title="Link t
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

device_support.html

@@ -799,7 +799,7 @@ <h2>Template files<a class="headerlink" href="#template-files" title="Link to th
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

driver_architecture.html

@@ -261,7 +261,7 @@ <h2>Platform independence<a class="headerlink" href="#platform-independence" tit
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

example_applications.html

@@ -292,7 +292,7 @@ <h1>Example Applications<a class="headerlink" href="#example-applications" title
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

genindex.html

@@ -91,7 +91,7 @@ <h1 id="index">Index</h1>
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

index.html

@@ -113,7 +113,7 @@ <h2>Table of Contents<a class="headerlink" href="#table-of-contents" title="Link
 </ul>
 </li>
 <li class="toctree-l1"><a class="reference internal" href="creating_driver.html">Creating a <strong>modbus</strong> port driver</a><ul>
-<li class="toctree-l2"><a class="reference internal" href="creating_driver.html#tcp-ip">TCP/IP</a></li>
+<li class="toctree-l2"><a class="reference internal" href="creating_driver.html#tcp-ip-udp-ip">TCP/IP UDP/IP</a></li>
 <li class="toctree-l2"><a class="reference internal" href="creating_driver.html#serial-rtu">Serial RTU</a></li>
 <li class="toctree-l2"><a class="reference internal" href="creating_driver.html#serial-ascii">Serial ASCII</a></li>
 <li class="toctree-l2"><a class="reference internal" href="creating_driver.html#modbusinterposeconfig">modbusInterposeConfig</a></li>
@@ -167,7 +167,7 @@ <h2>Table of Contents<a class="headerlink" href="#table-of-contents" title="Link
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

medm_screens.html

@@ -187,7 +187,7 @@ <h2>Koyo_4ADC.adl<a class="headerlink" href="#koyo-4adc-adl" title="Link to this
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

overview.html

@@ -102,38 +102,7 @@ <h1>Overview of Modbus<a class="headerlink" href="#overview-of-modbus" title="Li
 <section id="modbus-communication-links">
 <h2>Modbus communication links<a class="headerlink" href="#modbus-communication-links" title="Link to this heading"></a></h2>
 <p>Modbus supports the following 3 communication-link layers:</p>
-<table class="table-bordered table-striped table-hover docutils align-default">
-<thead>
-<tr class="row-odd"><th class="head"><p>Link type</p></th>
-<th class="head"><p>Description</p></th>
-</tr>
-</thead>
-<tbody>
-<tr class="row-even"><td><p>TCP</p></td>
-<td><p>TCP/IP using standard port 502.</p></td>
-</tr>
-<tr class="row-odd"><td><p>RTU</p></td>
-<td><p>RTU is normally run over serial communication links, i.e. RS-232,
-RS-422, or RS-485. RTU uses an additional CRC for packet checking. The
-protocol directly transmits each byte as 8 data bits, so uses “binary”
-rather than ASCII encoding. When using serial links start and end of
-message frames is detected by timing rather than by specific characters.
-RTU can also be run over TCP, though this is less common than the
-standard Modbus TCP without RTU.</p></td>
-</tr>
-<tr class="row-even"><td><p>Serial ASCII</p></td>
-<td><p>Serial protocol, which is normally run over serial communication links,
-i.e. RS-232, RS-422, or RS-485. Serial ASCII uses an additional LRC for
-packet checking. The protocol encodes each byte as 2 ASCII characters.
-The start and end of message frames is detected by specific characters
-(“:” to start a message and CR/LF to end a message). This protocol is
-less efficient than RTU, but may be more reliable in some environments.
-ASCII can also be run over TCP, though this is much less common than the
-standard Modbus TCP.</p></td>
-</tr>
-</tbody>
-</table>
-<p>This <strong>modbus</strong> package supports all of the above Modbus
+<p class="table-bordered table-striped table-hover">This <strong>modbus</strong> package supports all of the above Modbus
 communication-link layers.</p>
 </section>
 <section id="modbus-data-types">
@@ -383,7 +352,7 @@ <h2>More information on Modbus<a class="headerlink" href="#more-information-on-m
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>
 

search.html

@@ -99,7 +99,7 @@
 
   <div role="contentinfo">
     <p>&#169; Copyright 2023, Mark Rivers.
-      <span class="lastupdated">Last updated on 2024-March-25.
+      <span class="lastupdated">Last updated on 2024-April-16.
       </span></p>
   </div>