mirror of https://gitee.com/openkylin/linux.git
64 lines
2.0 KiB
ReStructuredText
64 lines
2.0 KiB
ReStructuredText
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.. Permission is granted to copy, distribute and/or modify this
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.. document under the terms of the GNU Free Documentation License,
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.. Version 1.1 or any later version published by the Free Software
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.. Foundation, with no Invariant Sections, no Front-Cover Texts
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.. and no Back-Cover Texts. A copy of the license is included at
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.. Documentation/userspace-api/media/fdl-appendix.rst.
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..
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.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
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.. _dvb_frontend:
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#######################
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Digital TV Frontend API
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#######################
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The Digital TV frontend API was designed to support three groups of delivery
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systems: Terrestrial, cable and Satellite. Currently, the following
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delivery systems are supported:
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- Terrestrial systems: DVB-T, DVB-T2, ATSC, ATSC M/H, ISDB-T, DVB-H,
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DTMB, CMMB
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- Cable systems: DVB-C Annex A/C, ClearQAM (DVB-C Annex B)
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- Satellite systems: DVB-S, DVB-S2, DVB Turbo, ISDB-S, DSS
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The Digital TV frontend controls several sub-devices including:
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- Tuner
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- Digital TV demodulator
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- Low noise amplifier (LNA)
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- Satellite Equipment Control (SEC) [#f1]_.
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The frontend can be accessed through ``/dev/dvb/adapter?/frontend?``.
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Data types and ioctl definitions can be accessed by including
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``linux/dvb/frontend.h`` in your application.
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.. note::
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Transmission via the internet (DVB-IP) and MMT (MPEG Media Transport)
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is not yet handled by this API but a future extension is possible.
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.. [#f1]
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On Satellite systems, the API support for the Satellite Equipment
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Control (SEC) allows to power control and to send/receive signals to
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control the antenna subsystem, selecting the polarization and choosing
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the Intermediate Frequency IF) of the Low Noise Block Converter Feed
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Horn (LNBf). It supports the DiSEqC and V-SEC protocols. The DiSEqC
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(digital SEC) specification is available at
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`Eutelsat <http://www.eutelsat.com/satellites/4_5_5.html>`__.
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.. toctree::
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:maxdepth: 1
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query-dvb-frontend-info
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dvb-fe-read-status
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dvbproperty
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frontend_fcalls
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