configuration.html

<!DOCTYPE html>
<!--
 | Generated by Apache Maven Doxia Site Renderer 1.8.1 from src/site/apt/configuration.apt.vm at 2018-10-21
 | Rendered using Apache Maven Fluido Skin 1.7
-->
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="Date-Revision-yyyymmdd" content="20181021" />
    <meta http-equiv="Content-Language" content="en" />
    <title>usb4java &#x2013; Configuration</title>
    <link rel="stylesheet" href="./css/apache-maven-fluido-1.7.min.css" />
    <link rel="stylesheet" href="./css/site.css" />
    <link rel="stylesheet" href="./css/print.css" media="print" />
    <script type="text/javascript" src="./js/apache-maven-fluido-1.7.min.js"></script>
<link href="favicon.ico" rel="SHORTCUT ICON" />
  </head>
  <body class="topBarDisabled">
    <a href="https://github.com/usb4java">
      <img style="position: absolute; top: 0; right: 0; border: 0; z-index: 10000;"
        src="https://s3.amazonaws.com/github/ribbons/forkme_right_red_aa0000.png"
        alt="Fork me on GitHub">
    </a>
    <div class="container-fluid">
      <div id="banner">
        <div class="pull-left"><a href="./" id="bannerLeft"><img src="images/logo.png"  alt="usb4java"/></a></div>
        <div class="pull-right"></div>
        <div class="clear"><hr/></div>
      </div>

      <div id="breadcrumbs">
        <ul class="breadcrumb">
        <li id="publishDate">Last Published: 2018-10-21<span class="divider">|</span>
</li>
          <li id="projectVersion">Version: 1.3.0<span class="divider">|</span></li>
      <li class=""><a href="./" title="usb4java">usb4java</a><span class="divider">/</span></li>
    <li class="active ">Configuration</li>
      <li class="pull-right"><span class="divider">|</span>
<a href="http://libusb.info/" class="externalLink" title="libusb">libusb</a></li>
      <li class="pull-right"><a href="http://javax-usb.sourceforge.net/" class="externalLink" title="javax-usb">javax-usb</a></li>
        </ul>
      </div>
      <div class="row-fluid">
        <div id="leftColumn" class="span2">
          <div class="well sidebar-nav">
    <ul class="nav nav-list">
      <li class="nav-header">usb4java</li>
    <li><a href="index.html" title="About"><span class="none"></span>About</a></li>
    <li><a href="quickstart/index.html" title="Quick start"><span class="icon-chevron-right"></span>Quick start</a></li>
    <li><a href="faq.html" title="FAQ"><span class="none"></span>FAQ</a></li>
    <li class="active"><a href="#"><span class="none"></span>Configuration</a></li>
    <li><a href="nativelibs.html" title="Native libs"><span class="none"></span>Native libs</a></li>
      <li class="nav-header">Project Documentation</li>
    <li><a href="project-info.html" title="Project Information"><span class="icon-chevron-right"></span>Project Information</a></li>
    <li><a href="project-reports.html" title="Project Reports"><span class="icon-chevron-right"></span>Project Reports</a></li>
</ul>
          <hr />
          <div id="poweredBy">
            <div class="clear"></div>
            <div class="clear"></div>
            <div class="clear"></div>
            <div class="clear"></div>
<a href="http://maven.apache.org/" title="Built by Maven" class="poweredBy"><img class="builtBy" alt="Built by Maven" src="./images/logos/maven-feather.png" /></a>
            </div>
          </div>
        </div>
        <div id="bodyColumn"  class="span10" >
<div class="section">
<h2><a name="Configuration"></a>Configuration</h2>
<p>The configuration options explained here are only valid for the javax-usb extension of usb4java. If you access your USB devices with the native libusb API then no configuration is needed.</p>
<div class="section">
<h3><a name="Selecting_usb4java_as_javax-usb_implementation"></a>Selecting usb4java as javax-usb implementation</h3>
<p>To tell the USB Host Manager of <i>javax-usb</i> to use the <i>usb4java</i> implementation you have to put the following property into the <i>javax.usb.properties</i> file which must be located in the root of your classpath:</p>
<div class="source"><pre class="prettyprint">javax.usb.services = org.usb4java.javax.Services</pre></div>
<p><i>usb4java</i> can be configured by adding more properties to this file as described in the following sections.</p></div>
<div class="section">
<h3><a name="Communication_timeout"></a>Communication timeout</h3>
<p>The default USB communication timeout of <i>usb4java</i> is 2500 milliseconds. To change this to 250 milliseconds for example add this to the properties file:</p>
<div class="source"><pre class="prettyprint">org.usb4java.javax.timeout = 250</pre></div></div>
<div class="section">
<h3><a name="Scan_interval"></a>Scan interval</h3>
<p>The default USB device scan interval of <i>usb4java</i> is 500 milliseconds. To change this to 1000 milliseconds for example add this to the properties file:</p>
<div class="source"><pre class="prettyprint">org.usb4java.javax.scanInterval = 1000</pre></div>
<p>When you set this interval to 0 then <i>usb4java</i> only scans once during application startup. If you want to trigger a manual device <i>scan</i> you can do it by calling the scan method on the USB services class (Must be casted to the <i>usb4java</i> implementation, because this is not a javax-usb feature:</p>
<div class="source"><pre class="prettyprint">((org.usb4java.javax.Services) UsbHostManager.getUsbServices()).scan();</pre></div></div>
<div class="section">
<h3><a name="Use_USBDK"></a>Use USBDK</h3>
<p>If you want to use <a class="externalLink" href="https://github.com/daynix/UsbDk">USBDK</a> on Windows then you have to enable the feature with the following entry:</p>
<div class="source"><pre class="prettyprint">org.usb4java.javax.useUSBDK = true</pre></div>
<p>This setting is ignored on other platforms.</p></div></div>
        </div>
      </div>
    </div>
    <hr/>
    <footer>
      <div class="container-fluid">
        <div class="row-fluid">
            <p>Copyright &copy;2011&#x2013;2018
<a href="http://usb4java.org/">usb4java Team</a>.
All rights reserved.</p>
        </div>
      </div>
    </footer>
  </body>
</html>