Description
Get or set graphic equalizer for one or all logical channels inside a cluster.
Files
usbd_audio_drv_<codec-name>.h / usbd_audio_drv_<codec-name>.c
Prototype
Arguments
p_audio_drv
Pointer to audio driver structure.
req
Graphic Equalizer request:
USBD_AUDIO_REQ_GET_CUR
USBD_AUDIO_REQ_GET_RES
USBD_AUDIO_REQ_GET_MIN
USBD_AUDIO_REQ_GET_MAX
USBD_AUDIO_REQ_SET_CUR
unit_id
Feature Unit ID.
log_ch_nbr
Logical channel number.
nbr_bands_present
Number of band presents. Used only with SET_CUR
request.
p_bm_bands_present
Pointer to bitmap indicating a new setting for one or several frequency band(s). Used only with SET_CUR
request.
p_buf
Pointer to the request value to set or get.
Returned Value
DEF_OK
, if NO error(s) occurred and request is supported.
DEF_FAIL
, otherwise.
Callers
Audio Class.
Implementation guidelines
- The Graphic Equalizer Control values range allowed for Feature Unit is:
- From +31.75 dB (0x7F) down to –32.00 dB (0x80) for CUR, MIN, and MAX attributes.
- From 0.25 dB (0x01) to +31.75 dB (0x7F) for RES attribute.
log_ch_nbr
allows you to get or set the graphic equalizer for a specific channel. Whenlog_ch_nbr
is 0, you get or set the graphic equalizer for all channels. Indeed, the logical channel #0 represents the master channel and encompasses all channels.