| .. -*- coding: utf-8; mode: rst -*- |
| |
| .. _FE_SET_TONE: |
| |
| ***************** |
| ioctl FE_SET_TONE |
| ***************** |
| |
| Name |
| ==== |
| |
| FE_SET_TONE - Sets/resets the generation of the continuous 22kHz tone. |
| |
| |
| Synopsis |
| ======== |
| |
| .. c:function:: int ioctl( int fd, FE_SET_TONE, enum fe_sec_tone_mode *tone ) |
| :name: FE_SET_TONE |
| |
| |
| Arguments |
| ========= |
| |
| ``fd`` |
| File descriptor returned by :ref:`open() <frontend_f_open>`. |
| |
| ``tone`` |
| pointer to enum :c:type:`fe_sec_tone_mode` |
| |
| |
| Description |
| =========== |
| |
| This ioctl is used to set the generation of the continuous 22kHz tone. |
| This call requires read/write permissions. |
| |
| Usually, satellite antenna subsystems require that the digital TV device |
| to send a 22kHz tone in order to select between high/low band on some |
| dual-band LNBf. It is also used to send signals to DiSEqC equipment, but |
| this is done using the DiSEqC ioctls. |
| |
| .. attention:: If more than one device is connected to the same antenna, |
| setting a tone may interfere on other devices, as they may lose the |
| capability of selecting the band. So, it is recommended that applications |
| would change to SEC_TONE_OFF when the device is not used. |
| |
| .. c:type:: fe_sec_tone_mode |
| |
| .. flat-table:: enum fe_sec_tone_mode |
| :header-rows: 1 |
| :stub-columns: 0 |
| |
| |
| - .. row 1 |
| |
| - ID |
| |
| - Description |
| |
| - .. row 2 |
| |
| - .. _SEC-TONE-ON: |
| |
| ``SEC_TONE_ON`` |
| |
| - Sends a 22kHz tone burst to the antenna |
| |
| - .. row 3 |
| |
| - .. _SEC-TONE-OFF: |
| |
| ``SEC_TONE_OFF`` |
| |
| - Don't send a 22kHz tone to the antenna (except if the |
| FE_DISEQC_* ioctls are called) |
| |
| |
| Return Value |
| ============ |
| |
| On success 0 is returned, on error -1 and the ``errno`` variable is set |
| appropriately. The generic error codes are described at the |
| :ref:`Generic Error Codes <gen-errors>` chapter. |
