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[media] DocBook: Improve DVB frontend description

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The DVB frontend API got bitrotten. Update it.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
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Mauro Carvalho Chehab 2015-05-25 14:24:38 -03:00
parent 0b0f1a0056
commit ee072ed7e3
1 changed files with 28 additions and 16 deletions
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44
Documentation/DocBook/media/dvb/frontend.xml
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@ -1,30 +1,42 @@
<title>DVB Frontend API</title> <title>DVB Frontend API</title>
<para>The DVB frontend device controls the tuner and DVB demodulator <para>The DVB frontend API was designed to support three types of delivery systems:</para>
hardware. It can be accessed through <emphasis <itemizedlist>
role="bold">/dev/dvb/adapter0/frontend0</emphasis>. Data types and and <listitem>Terrestrial systems: DVB-T, DVB-T2, ATSC, ATSC M/H, ISDB-T, DVB-H, DTMB, CMMB</listitem>
ioctl definitions can be accessed by including <emphasis <listitem>Cable systems: DVB-C Annex A/C, ClearQAM (DVB-C Annex B), ISDB-C</listitem>
role="bold">linux/dvb/frontend.h</emphasis> in your application.</para> <listitem>Satellital systems: DVB-S, DVB-S2, DVB Turbo, ISDB-S, DSS</listitem>
</itemizedlist>
<para>The DVB frontend controls several sub-devices including:</para>
<itemizedlist>
<listitem>Tuner</listitem>,
<listitem>Digital TV demodulator</listitem>
<listitem>Low noise amplifier (LNA)</listitem>
<listitem>Satellite Equipment Control (SEC) hardware (only for Satellite).</listitem>
</itemizedlist>
<para>The frontend can be accessed through
<emphasis role="bold">/dev/dvb/adapter?/frontend?</emphasis>. Data types and
ioctl definitions can be accessed by including
<emphasis role="bold">linux/dvb/frontend.h</emphasis> in your application.
</para>
<para>DVB frontends come in three varieties: DVB-S (satellite), DVB-C <para>NOTE: Transmission via the internet (DVB-IP)
(cable) and DVB-T (terrestrial). Transmission via the internet (DVB-IP) is not yet handled by this API but a future extension is possible.</para>
is not yet handled by this API but a future extension is possible. For <para>On Satellital systems, the API support for the Satellite Equipment Control
DVB-S the frontend device also supports satellite equipment control (SEC) allows to power control and to send/receive signals to control the
(SEC) via DiSEqC and V-SEC protocols. The DiSEqC (digital SEC) antenna subsystem, selecting the polarization and choosing the Intermediate
specification is available from Frequency IF) of the Low Noise Block Converter Feed Horn (LNBf). It
supports the DiSEqC and V-SEC protocols. The DiSEqC (digital SEC)
specification is available at
<ulink url="http://www.eutelsat.com/satellites/4_5_5.html">Eutelsat</ulink>.</para> <ulink url="http://www.eutelsat.com/satellites/4_5_5.html">Eutelsat</ulink>.</para>
<para>Note that the DVB API may also be used for MPEG decoder-only PCI
cards, in which case there exists no frontend device.</para>
<section id="frontend_types"> <section id="frontend_types">
<title>Frontend Data Types</title> <title>Frontend Data Types</title>
<section id="fe-type-t"> <section id="fe-type-t">
<title>Frontend type</title> <title>Frontend type</title>
<para>For historical reasons, frontend types are named by the type of modulation used in <para>For historical reasons, frontend types are named by the type of modulation
transmission. The fontend types are given by fe_type_t type, defined as:</para> used in transmission. The fontend types are given by fe_type_t type, defined as:</para>
<table pgwide="1" frame="none" id="fe-type"> <table pgwide="1" frame="none" id="fe-type">
<title>Frontend types</title> <title>Frontend types</title>