Controls

Modules
	AES/EBU Digital audio receiver controls
	The AESEBU receiver receives audio from a standard digital audio interface (AESEBU or SPDIF).
	AES/EBU Digital audio transmitter control
	The AESEBU transmitter transmits audio via a standard digital audio interface (AESEBU or SPDIF).
	Bitstream control
	Control synchronous bitstream I/O.
	Channel Mode control
	A Channel Mode allows you to swap the left and right channels, mix the left and right channels into the left or right channel only, or send the left or right channels to both left and right.
	Cobranet control
	A cobranet adapter has one cobranet control for each cobranet interface (usually only one).
	Compressor Expander control
	The compander multiplies its input signal by a factor that is dependent on the amplitude of that signal.
	Level Control
	The level control value determines the full scale reference level (also known as trim) of an analog input or output.
	Meter Control
	The meter control returns information about the level of the audio signal at the position of the control.
	Microphone control
	A Microphone control of type HPI_CONTROL_MICROPHONE is always located on a source node of type HPI_SOURCE_NODE_MICROPHONE.
	Multiplexer control
	This control allows one of many sources to be connected to a destination Typically used on the instream (record) side to select a record input or on the linein to select analog or digital input.
	SampleClock control
	The SampleClock control is used to control the clock source for the adapter.
	Tone Detector control
	The tone detector monitors its inputs for the presence of any of a number of tones.
	Silence Detector Controls
	The silence detector control monitors its input for silence exceeding a set duration.
	Tuner Controls
	The tuner control sets the band and frequency of a tuner, and measures the RF level.
	PAD Control
	The PAD control supports the reading of "Program Associated Data" from a tuner node.
	Volume Control
	Volume controls are usually situated on a "connection" between a source node and a destination node.
	Vox control
	VOX controls are always situated on a destination node of type HPI_DESTNODE_ISTREAM.
	Universal Control
	A universal control is a control type that supports abstract mechanisms for accessing data, thereby making it capable of representing any controllable parameter.
	RDS analysis functions
	Parametric Equalizer control
	The parametric equalizer control consists of a series of filters that are applied successively to the signal.
Functions
hpi_err_t	HPI_ControlQuery (const hpi_hsubsys_t *phSubSys, const hpi_handle_t hControl, const uint16_t wAttrib, const uint32_t dwIndex, const uint32_t dwParam, uint32_t *pdwSetting)

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Function Documentation

hpi_err_t HPI_ControlQuery	(	const hpi_hsubsys_t *	phSubSys,
		const hpi_handle_t	hControl,
		const uint16_t	wAttrib,
		const uint32_t	dwIndex,
		const uint32_t	dwParam,
		uint32_t *	pdwSetting
	)

Parameters:

phSubSys	Vestigial subsys handle (unused), may be set to NULL
hControl	Control to query
wAttrib	An attribute of the control
dwIndex	Index for possible attribute values
dwParam	Supplementary parameter
pdwSetting	One of N possible settings for the control attribute, specified by dwIndex=0..N-1(and possibly depending on the value of the supplementary parameter)

Referenced by HPI_AESEBU_Receiver_QueryFormat(), HPI_AESEBU_Transmitter_QueryFormat(), HPI_ChannelMode_QueryMode(), HPI_Meter_QueryChannels(), HPI_SampleClock_QueryLocalRate(), HPI_SampleClock_QuerySource(), HPI_SampleClock_QuerySourceIndex(), HPI_Tuner_QueryBand(), HPI_Tuner_QueryDeemphasis(), HPI_Tuner_QueryFrequency(), HPI_Tuner_QueryGain(), HPI_Tuner_QueryProgram(), HPI_Volume_QueryAutoFadeProfile(), and HPI_Volume_QueryChannels().