SoundCtrl_ExamineMixer Block (changes)
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SoundControl
» SWI Calls
» SoundCtrl_ExamineMixer
» SoundCtrl_ExamineMixer Block
SoundCtrl_ExamineMixer Block
| Byte Offset | |
|---|---|
| 0-1 | Flags: |
| Bit 0 set => Gain setting is fixed | |
| Bit 1 set => Mono | |
| Bit 2 set => Channel should be muted by default | |
| Bits 3-15: Reserved | |
| 2-3 | Category |
| 4-7 | Minimum gain |
| 8-11 | Maximum gain |
| 12-15 | Minimum step size/granularity of gain changes |
Notes
Although the block length shown here is 16 bytes, not all mixers return the same amount of data. The block size value returned by SoundCtrl_ExamineMixer in R3 should always be used to determine how much data is available. Currently defined block sizes are 4 and 16 bytes. Be aware that larger sizes may be introduced in the future – your code should only read as many bytes as it understands.
All gain values are specified in units of 1/16dB, e.g. -16 corresponds to -1dB. Because not all mixers allow such a fine level of control over their gain, the word at offset 12 is used to indicate the minimum step size that is supported by the channel.
See also
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