OpenCloudOS-Kernel/Documentation/userspace-api/media/dvb/frontend.rst

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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
.. _dvb_frontend:
#######################
Digital TV Frontend API
#######################
The Digital TV frontend API was designed to support three groups of delivery
systems: Terrestrial, cable and Satellite. Currently, the following
delivery systems are supported:
- Terrestrial systems: DVB-T, DVB-T2, ATSC, ATSC M/H, ISDB-T, DVB-H,
DTMB, CMMB
- Cable systems: DVB-C Annex A/C, ClearQAM (DVB-C Annex B)
- Satellite systems: DVB-S, DVB-S2, DVB Turbo, ISDB-S, DSS
The Digital TV frontend controls several sub-devices including:
- Tuner
- Digital TV demodulator
- Low noise amplifier (LNA)
- Satellite Equipment Control (SEC) [#f1]_.
The frontend can be accessed through ``/dev/dvb/adapter?/frontend?``.
Data types and ioctl definitions can be accessed by including
``linux/dvb/frontend.h`` in your application.
.. note::
Transmission via the internet (DVB-IP) and MMT (MPEG Media Transport)
is not yet handled by this API but a future extension is possible.
.. [#f1]
On Satellite systems, the API support for the Satellite Equipment
Control (SEC) allows to power control and to send/receive signals to
control the antenna subsystem, selecting the polarization and choosing
the Intermediate 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
`Eutelsat <http://www.eutelsat.com/satellites/4_5_5.html>`__.
.. toctree::
:maxdepth: 1
query-dvb-frontend-info
dvb-fe-read-status
dvbproperty
frontend_fcalls