1.. Permission is granted to copy, distribute and/or modify this 2.. document under the terms of the GNU Free Documentation License, 3.. Version 1.1 or any later version published by the Free Software 4.. Foundation, with no Invariant Sections, no Front-Cover Texts 5.. and no Back-Cover Texts. A copy of the license is included at 6.. Documentation/userspace-api/media/fdl-appendix.rst. 7.. 8.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections 9 10************* 11Frontend type 12************* 13 14For historical reasons, frontend types are named by the type of 15modulation used in transmission. The fontend types are given by 16fe_type_t type, defined as: 17 18 19.. c:type:: fe_type 20 21.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| 22 23.. flat-table:: Frontend types 24 :header-rows: 1 25 :stub-columns: 0 26 :widths: 3 1 4 27 28 29 - .. row 1 30 31 - fe_type 32 33 - Description 34 35 - :ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>` equivalent 36 type 37 38 - .. row 2 39 40 - .. _FE-QPSK: 41 42 ``FE_QPSK`` 43 44 - For DVB-S standard 45 46 - ``SYS_DVBS`` 47 48 - .. row 3 49 50 - .. _FE-QAM: 51 52 ``FE_QAM`` 53 54 - For DVB-C annex A standard 55 56 - ``SYS_DVBC_ANNEX_A`` 57 58 - .. row 4 59 60 - .. _FE-OFDM: 61 62 ``FE_OFDM`` 63 64 - For DVB-T standard 65 66 - ``SYS_DVBT`` 67 68 - .. row 5 69 70 - .. _FE-ATSC: 71 72 ``FE_ATSC`` 73 74 - For ATSC standard (terrestrial) or for DVB-C Annex B (cable) used 75 in US. 76 77 - ``SYS_ATSC`` (terrestrial) or ``SYS_DVBC_ANNEX_B`` (cable) 78 79 80Newer formats like DVB-S2, ISDB-T, ISDB-S and DVB-T2 are not described 81at the above, as they're supported via the new 82:ref:`FE_GET_PROPERTY/FE_GET_SET_PROPERTY <FE_GET_PROPERTY>` 83ioctl's, using the :ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>` 84parameter. 85 86In the old days, struct :c:type:`dvb_frontend_info` 87used to contain ``fe_type_t`` field to indicate the delivery systems, 88filled with either ``FE_QPSK, FE_QAM, FE_OFDM`` or ``FE_ATSC``. While this 89is still filled to keep backward compatibility, the usage of this field 90is deprecated, as it can report just one delivery system, but some 91devices support multiple delivery systems. Please use 92:ref:`DTV_ENUM_DELSYS <DTV-ENUM-DELSYS>` instead. 93 94On devices that support multiple delivery systems, struct 95:c:type:`dvb_frontend_info`::``fe_type_t`` is 96filled with the currently standard, as selected by the last call to 97:ref:`FE_SET_PROPERTY <FE_GET_PROPERTY>` using the 98:ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>` property. 99