1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>Linux DVB Devices</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="LINUX MEDIA INFRASTRUCTURE API"><link rel="up" href="dvb_introdution.html" title="Chapter 8. Introduction"><link rel="prev" href="overview.html" title="Overview"><link rel="next" href="include_files.html" title="API include files"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Linux DVB Devices</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="overview.html">Prev</a> </td><th width="60%" align="center">Chapter 8. Introduction</th><td width="20%" align="right"> <a accesskey="n" href="include_files.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="dvb_devices"></a>Linux DVB Devices</h2></div></div></div><p>The Linux DVB API lets you control these hardware components 2through currently six Unix-style character devices for video, audio, 3frontend, demux, CA and IP-over-DVB networking. The video and audio 4devices control the MPEG2 decoder hardware, the frontend device the 5tuner and the DVB demodulator. The demux device gives you control over 6the PES and section filters of the hardware. If the hardware does not 7support filtering these filters can be implemented in software. Finally, 8the CA device controls all the conditional access capabilities of the 9hardware. It can depend on the individual security requirements of the 10platform, if and how many of the CA functions are made available to the 11application through this device.</p><p>All devices can be found in the <span class="tt">/dev</span> 12tree under <span class="tt">/dev/dvb</span>. The individual devices 13are called:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p><span class="tt">/dev/dvb/adapterN/audioM</span>,</p></li><li class="listitem"><p><span class="tt">/dev/dvb/adapterN/videoM</span>,</p></li><li class="listitem"><p><span class="tt">/dev/dvb/adapterN/frontendM</span>,</p></li><li class="listitem"><p><span class="tt">/dev/dvb/adapterN/netM</span>,</p></li><li class="listitem"><p><span class="tt">/dev/dvb/adapterN/demuxM</span>,</p></li><li class="listitem"><p><span class="tt">/dev/dvb/adapterN/dvrM</span>,</p></li><li class="listitem"><p><span class="tt">/dev/dvb/adapterN/caM</span>,</p></li></ul></div><p>where N enumerates the DVB PCI cards in a system starting 14from 0, and M enumerates the devices of each type within each 15adapter, starting from 0, too. We will omit the “<span class="tt">/dev/dvb/adapterN/</span>” in the further dicussion 16of these devices. The naming scheme for the devices is the same wheter 17devfs is used or not.</p><p>More details about the data structures and function calls of all 18the devices are described in the following chapters.</p></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="overview.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="dvb_introdution.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="include_files.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Overview </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> API include files</td></tr></table></div></body></html> 19