1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2
3*************
4Frontend type
5*************
6
7For historical reasons, frontend types are named by the type of
8modulation used in transmission. The fontend types are given by
9fe_type_t type, defined as:
10
11
12.. c:type:: fe_type
13
14.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.5cm}|
15
16.. flat-table:: Frontend types
17    :header-rows:  1
18    :stub-columns: 0
19    :widths:       3 1 4
20
21
22    -  .. row 1
23
24       -  fe_type
25
26       -  Description
27
28       -  :ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>` equivalent
29	  type
30
31    -  .. row 2
32
33       -  .. _FE-QPSK:
34
35	  ``FE_QPSK``
36
37       -  For DVB-S standard
38
39       -  ``SYS_DVBS``
40
41    -  .. row 3
42
43       -  .. _FE-QAM:
44
45	  ``FE_QAM``
46
47       -  For DVB-C annex A standard
48
49       -  ``SYS_DVBC_ANNEX_A``
50
51    -  .. row 4
52
53       -  .. _FE-OFDM:
54
55	  ``FE_OFDM``
56
57       -  For DVB-T standard
58
59       -  ``SYS_DVBT``
60
61    -  .. row 5
62
63       -  .. _FE-ATSC:
64
65	  ``FE_ATSC``
66
67       -  For ATSC standard (terrestrial) or for DVB-C Annex B (cable) used
68	  in US.
69
70       -  ``SYS_ATSC`` (terrestrial) or ``SYS_DVBC_ANNEX_B`` (cable)
71
72
73Newer formats like DVB-S2, ISDB-T, ISDB-S and DVB-T2 are not described
74at the above, as they're supported via the new
75:ref:`FE_GET_PROPERTY/FE_GET_SET_PROPERTY <FE_GET_PROPERTY>`
76ioctl's, using the :ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>`
77parameter.
78
79In the old days, struct :c:type:`dvb_frontend_info`
80used to contain ``fe_type_t`` field to indicate the delivery systems,
81filled with either ``FE_QPSK, FE_QAM, FE_OFDM`` or ``FE_ATSC``. While this
82is still filled to keep backward compatibility, the usage of this field
83is deprecated, as it can report just one delivery system, but some
84devices support multiple delivery systems. Please use
85:ref:`DTV_ENUM_DELSYS <DTV-ENUM-DELSYS>` instead.
86
87On devices that support multiple delivery systems, struct
88:c:type:`dvb_frontend_info`::``fe_type_t`` is
89filled with the currently standard, as selected by the last call to
90:ref:`FE_SET_PROPERTY <FE_GET_PROPERTY>` using the
91:ref:`DTV_DELIVERY_SYSTEM <DTV-DELIVERY-SYSTEM>` property.
92