Documentation/linux_tv/media/dvb/fe-set-tone.rst

   1 .. -*- coding: utf-8; mode: rst -*-
   2
   3 .. _FE_SET_TONE:
   4
   5 *****************
   6 ioctl FE_SET_TONE
   7 *****************
   8
   9 *man FE_SET_TONE(2)*
  10
  11 Sets/resets the generation of the continuous 22kHz tone.
  12
  13
  14 Synopsis
  15 ========
  16
  17 .. c:function:: int ioctl( int fd, int request, enum fe_sec_tone_mode *tone )
  18
  19 Arguments
  20 =========
  21
  22 ``fd``
  23     File descriptor returned by :ref:`open() <frontend_f_open>`.
  24
  25 ``request``
  26     FE_SET_TONE
  27
  28 ``tone``
  29     pointer to enum :ref:`fe_sec_tone_mode <fe-sec-tone-mode>`
  30
  31
  32 Description
  33 ===========
  34
  35 This ioctl is used to set the generation of the continuous 22kHz tone.
  36 This call requires read/write permissions.
  37
  38 Usually, satellite antenna subsystems require that the digital TV device
  39 to send a 22kHz tone in order to select between high/low band on some
  40 dual-band LNBf. It is also used to send signals to DiSEqC equipment, but
  41 this is done using the DiSEqC ioctls.
  42
  43 NOTE: if more than one device is connected to the same antenna, setting
  44 a tone may interfere on other devices, as they may lose the capability
  45 of selecting the band. So, it is recommended that applications would
  46 change to SEC_TONE_OFF when the device is not used.
  47
  48 RETURN VALUE
  49
  50 On success 0 is returned, on error -1 and the ``errno`` variable is set
  51 appropriately. The generic error codes are described at the
  52 :ref:`Generic Error Codes <gen-errors>` chapter.
  53
  54
  55 .. _fe-sec-tone-mode-t:
  56
  57 enum fe_sec_tone_mode
  58 =====================
  59
  60
  61 .. _fe-sec-tone-mode:
  62
  63 .. flat-table:: enum fe_sec_tone_mode
  64     :header-rows:  1
  65     :stub-columns: 0
  66
  67
  68     -  .. row 1
  69
  70        -  ID
  71
  72        -  Description
  73
  74     -  .. row 2
  75
  76        -  .. _`SEC-TONE-ON`:
  77
  78           ``SEC_TONE_ON``
  79
  80        -  Sends a 22kHz tone burst to the antenna
  81
  82     -  .. row 3
  83
  84        -  .. _`SEC-TONE-OFF`:
  85
  86           ``SEC_TONE_OFF``
  87
  88        -  Don't send a 22kHz tone to the antenna (except if the
  89           FE_DISEQC_* ioctls are called)
  90
  91
  92
  93
  94 .. ------------------------------------------------------------------------------
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  96 .. library (https://github.com/return42/sphkerneldoc). The origin XML comes
  97 .. from the linux kernel, refer to:
  98 ..
  99 .. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook
 100 .. ------------------------------------------------------------------------------