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Diffstat (limited to 'Documentation/userspace-api/media/dvb/fe_property_parameters.rst')
| -rw-r--r-- | Documentation/userspace-api/media/dvb/fe_property_parameters.rst | 57 |
1 files changed, 28 insertions, 29 deletions
diff --git a/Documentation/userspace-api/media/dvb/fe_property_parameters.rst b/Documentation/userspace-api/media/dvb/fe_property_parameters.rst index 3f4ced2800e3..ce962d4a02c0 100644 --- a/Documentation/userspace-api/media/dvb/fe_property_parameters.rst +++ b/Documentation/userspace-api/media/dvb/fe_property_parameters.rst @@ -1,11 +1,4 @@ -.. Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/userspace-api/media/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later .. _fe_property_parameters: @@ -79,11 +72,11 @@ DTV_MODULATION ============== Specifies the frontend modulation type for delivery systems that -supports more multiple modulations. +support multiple modulations. The modulation can be one of the types defined by enum :c:type:`fe_modulation`. -Most of the digital TV standards offers more than one possible +Most of the digital TV standards offer more than one possible modulation type. The table below presents a summary of the types of modulation types @@ -96,16 +89,21 @@ ATSC (version 1) 8-VSB and 16-VSB. DMTB 4-QAM, 16-QAM, 32-QAM, 64-QAM and 4-QAM-NR. DVB-C Annex A/C 16-QAM, 32-QAM, 64-QAM and 256-QAM. DVB-C Annex B 64-QAM. +DVB-C2 QPSK, 16-QAM, 64-QAM, 256-QAM, 1024-QAM and 4096-QAM. DVB-T QPSK, 16-QAM and 64-QAM. DVB-T2 QPSK, 16-QAM, 64-QAM and 256-QAM. DVB-S No need to set. It supports only QPSK. DVB-S2 QPSK, 8-PSK, 16-APSK and 32-APSK. +DVB-S2X 8-APSK-L, 16-APSK-L, 32-APSK-L, 64-APSK and 64-APSK-L. ISDB-T QPSK, DQPSK, 16-QAM and 64-QAM. ISDB-S 8-PSK, QPSK and BPSK. ======================= ======================================================= .. note:: + As DVB-S2X specifies extensions to the DVB-S2 standard, the same + delivery system enum value is used (SYS_DVBS2). + Please notice that some of the above modulation types may not be defined currently at the Kernel. The reason is simple: no driver needed such definition yet. @@ -145,9 +143,8 @@ ISDB-T 5MHz, 6MHz, 7MHz and 8MHz, although most places (DTV_ISDBT_SB_SEGMENT_IDX, DTV_ISDBT_SB_SEGMENT_COUNT). #. On Satellite and Cable delivery systems, the bandwidth depends on - the symbol rate. So, the Kernel will silently ignore any setting - :ref:`DTV-BANDWIDTH-HZ`. I will however fill it back with a - bandwidth estimation. + the symbol rate. The kernel will silently ignore any :ref:`DTV-BANDWIDTH-HZ` + setting and overwrites it with bandwidth estimation. Such bandwidth estimation takes into account the symbol rate set with :ref:`DTV-SYMBOL-RATE`, and the rolloff factor, with is fixed for @@ -202,7 +199,7 @@ DTV_VOLTAGE Used on satellite delivery systems. The voltage is usually used with non-DiSEqC capable LNBs to switch the -polarzation (horizontal/vertical). When using DiSEqC epuipment this +polarization (horizontal/vertical). When using DiSEqC equipment this voltage has to be switched consistently to the DiSEqC commands as described in the DiSEqC spec. @@ -282,7 +279,7 @@ DTV_ISDBT_PARTIAL_RECEPTION Used only on ISDB. -If ``DTV_ISDBT_SOUND_BROADCASTING`` is '0' this bit-field represents +If ``DTV_ISDBT_SOUND_BROADCASTING`` is '0' this bit field represents whether the channel is in partial reception mode or not. If '1' ``DTV_ISDBT_LAYERA_*`` values are assigned to the center segment @@ -333,8 +330,8 @@ broadcaster has several possibilities to put those channels in the air: Assuming a normal 13-segment ISDB-T spectrum he can align the 8 segments from position 1-8 to 5-13 or anything in between. -The underlying layer of segments are subchannels: each segment is -consisting of several subchannels with a predefined IDs. A sub-channel +The underlying layer of segments are sub-channels: each segment is +consisting of several sub-channels with a predefined IDs. A sub-channel is used to help the demodulator to synchronize on the channel. An ISDB-T channel is always centered over all sub-channels. As for the @@ -730,7 +727,7 @@ DTV_ATSCMH_RS_FRAME_ENSEMBLE Used only on ATSC-MH. -Reed Solomon(RS) frame ensemble. +Reed Solomon (RS) frame ensemble. The acceptable values are defined by :c:type:`atscmh_rs_frame_ensemble`. @@ -861,9 +858,10 @@ The acceptable values are defined by :c:type:`fe_guard_interval`. #. If ``DTV_GUARD_INTERVAL`` is set the ``GUARD_INTERVAL_AUTO`` the hardware will try to find the correct guard interval (if capable) and will use TMCC to fill in the missing parameters. - #. Intervals ``GUARD_INTERVAL_1_128``, ``GUARD_INTERVAL_19_128`` - and ``GUARD_INTERVAL_19_256`` are used only for DVB-T2 at - present. + #. Interval ``GUARD_INTERVAL_1_64`` is used only for DVB-C2. + #. Interval ``GUARD_INTERVAL_1_128`` is used for both DVB-C2 and DVB_T2. + #. Intervals ``GUARD_INTERVAL_19_128`` and ``GUARD_INTERVAL_19_256`` are + used only for DVB-T2. #. Intervals ``GUARD_INTERVAL_PN420``, ``GUARD_INTERVAL_PN595`` and ``GUARD_INTERVAL_PN945`` are used only for DMTB at the present. On such standard, only those intervals and ``GUARD_INTERVAL_AUTO`` @@ -923,14 +921,15 @@ The acceptable values are defined by :c:type:`fe_hierarchy`. DTV_STREAM_ID ============= -Used on DVB-S2, DVB-T2 and ISDB-S. +Used on DVB-C2, DVB-S2, DVB-T2 and ISDB-S. -DVB-S2, DVB-T2 and ISDB-S support the transmission of several streams on -a single transport stream. This property enables the digital TV driver to -handle substream filtering, when supported by the hardware. By default, -substream filtering is disabled. +DVB-C2, DVB-S2, DVB-T2 and ISDB-S support the transmission of several +streams on a single transport stream. This property enables the digital +TV driver to handle substream filtering, when supported by the hardware. +By default, substream filtering is disabled. -For DVB-S2 and DVB-T2, the valid substream id range is from 0 to 255. +For DVB-C2, DVB-S2 and DVB-T2, the valid substream id range is from 0 to +255. For ISDB, the valid substream id range is from 1 to 65535. @@ -954,14 +953,14 @@ DTV_ENUM_DELSYS A Multi standard frontend needs to advertise the delivery systems provided. Applications need to enumerate the provided delivery systems, -before using any other operation with the frontend. Prior to it's +before using any other operation with the frontend. Prior to its introduction, FE_GET_INFO was used to determine a frontend type. A frontend which provides more than a single delivery system, FE_GET_INFO doesn't help much. Applications which intends to use a multistandard frontend must enumerate the delivery systems associated with it, rather than trying to use FE_GET_INFO. In the case of a legacy frontend, the result is just the same as with FE_GET_INFO, but -in a more structured format +in a more structured format. The acceptable values are defined by :c:type:`fe_delivery_system`. |