6.1.1.1. Frontend type¶
For historical reasons, frontend types are named by the type of modulation used in transmission. The fontend types are given by fe_type_t type, defined as:
-
fe_type
¶
fe_type | Description | DTV_DELIVERY_SYSTEM equivalent type |
---|---|---|
|
For DVB-S standard | SYS_DVBS |
|
For DVB-C annex A standard | SYS_DVBC_ANNEX_A |
|
For DVB-T standard | SYS_DVBT |
|
For ATSC standard (terrestrial) or for DVB-C Annex B (cable) used in US. | SYS_ATSC (terrestrial) or SYS_DVBC_ANNEX_B (cable) |
Newer formats like DVB-S2, ISDB-T, ISDB-S and DVB-T2 are not described at the above, as they're supported via the new FE_GET_PROPERTY/FE_GET_SET_PROPERTY ioctl's, using the DTV_DELIVERY_SYSTEM parameter.
In the old days, struct dvb_frontend_info
used to contain fe_type_t
field to indicate the delivery systems,
filled with either FE_QPSK, FE_QAM, FE_OFDM
or FE_ATSC
. While this
is still filled to keep backward compatibility, the usage of this field
is deprecated, as it can report just one delivery system, but some
devices support multiple delivery systems. Please use
DTV_ENUM_DELSYS instead.
On devices that support multiple delivery systems, struct
dvb_frontend_info
::fe_type_t
is
filled with the currently standard, as selected by the last call to
FE_SET_PROPERTY using the
DTV_DELIVERY_SYSTEM property.