Functions
uint8_t	SI4735::getCurrentVolume ()
	Get the Current Volume.

void	SI4735::setVolumeUp ()
	Set the Volume Up.

void	SI4735::setVolumeDown ()
	Set the Volume Down.

void	SI4735::setAudioMode (uint8_t audioMode)
	Sets the Audio Mode. See table below.

void	SI4735::setAmDelayNB (uint16_t value)
	Sets the delay before applying impulse blanking.

void	SI4735::digitalOutputFormat (uint8_t OSIZE, uint8_t OMONO, uint8_t OMODE, uint8_t OFALL)
	Configures the digital audio output format.

void	SI4735::digitalOutputSampleRate (uint16_t DOSR)
	Enables digital audio output and configures digital audio output sample rate in samples per second (sps).

void	SI4735::setVolume (uint8_t volume)
	Sets volume level (0 to 63)

void	SI4735::setAudioMute (bool off)
	Sets the audio on or off.

uint8_t	SI4735::getVolume ()
	Gets the current volume level.

void	SI4735::volumeUp ()
	Set sound volume level Up.

void	SI4735::volumeDown ()
	Set sound volume level Down.

Detailed Description

Function Documentation

◆ getCurrentVolume()

uint8_t SI4735::getCurrentVolume ( )

inline

Get the Current Volume.

Returns the current volume level.

Returns: uint8_t

◆ setVolumeUp()

void SI4735::setVolumeUp ( )

inline

Set the Volume Up.

Same volumeUp()

See also: volumeUp

References SI4735::volumeUp().

◆ setVolumeDown()

void SI4735::setVolumeDown ( )

inline

Set the Volume Down.

Same volumeDown()

Returns: voi

References SI4735::volumeDown().

◆ setAudioMode()

void SI4735::setAudioMode ( uint8_t audioMode )

inline

Sets the Audio Mode. See table below.

If you want to change the audio mode, call this function before call setAM(), setFM() or setSSB().

Sets the Si47XX device to use ANALOG or DIGITAL audio output. The table below shows the valid values.

This function will only take effect after calling setAM(), setFM() or setSSB().

Macro	Value (Binary)	Description
SI473X_ANALOG_AUDIO	0b00000101	Analog Audio Inputs
SI473X_DIGITAL_AUDIO1	0b00001011	Digital audio output (DCLK, LOUT/DFS, ROUT/DIO)
SI473X_DIGITAL_AUDIO2	0b10110000	Digital audio outputs (DCLK, DFS, DIO)
SI473X_DIGITAL_AUDIO3	0b10110101	Analog and digital audio outputs (LOUT/ROUT and DCLK, DFS,DIO)

See also: setAM(), setFM(), setSSB().

Parameters

audioMode One of the values options above

◆ setAmDelayNB()

void SI4735::setAmDelayNB ( uint16_t value )

inline

Sets the delay before applying impulse blanking.

Delay in micro-seconds before applying impulse blanking to the original samples. Default value is 172.

Parameters

value Delay in micro-seconds

◆ digitalOutputFormat()

void SI4735::digitalOutputFormat	(	uint8_t	OSIZE,
		uint8_t	OMONO,
		uint8_t	OMODE,
		uint8_t	OFALL
	)

Configures the digital audio output format.

Options: DCLK edge, data format, force mono, and sample precision.

ATTENTION: The document AN383; "Si47XX ANTENNA, SCHEMATIC, LAYOUT, AND DESIGN GUIDELINES"; rev 0.8; page 6; there is the following note: Crystal and digital audio mode cannot be used at the same time. Populate R1 and remove C10, C11, and X1 when using digital audio.

See also: Si47XX PROGRAMINGGUIDE; AN332 (REV 1.0); page 195.; Si47XX ANTENNA, SCHEMATIC, LAYOUT, AND DESIGN GUIDELINES"; AN383; rev 0.8; page 6;

Parameters

uint8_t	OSIZE Dgital Output Audio Sample Precision (0=16 bits, 1=20 bits, 2=24 bits, 3=8bits).
uint8_t	OMONO Digital Output Mono Mode (0=Use mono/stereo blend ).
uint8_t	OMODE Digital Output Mode (0=I2S, 6 = Left-justified, 8 = MSB at second DCLK after DFS pulse, 12 = MSB at first DCLK after DFS pulse).
uint8_t	OFALL Digital Output DCLK Edge (0 = use DCLK rising edge, 1 = use DCLK falling edge)

◆ digitalOutputSampleRate()

void SI4735::digitalOutputSampleRate ( uint16_t DOSR )

Enables digital audio output and configures digital audio output sample rate in samples per second (sps).

When DOSR[15:0] is 0, digital audio output is disabled. The over-sampling rate must be set in order to

satisfy a minimum DCLK of 1 MHz. To enable digital audio output, program DOSR[15:0] with the sample rate

in samples per second. The system controller must establish DCLK and DFS prior to enabling the digital

audio output else the device will not respond and will require reset. The sample rate must be set to 0

before the DCLK/DFS is removed. FM_TUNE_FREQ command must be sent after the POWER_UP command to start

the internal clocking before setting this property.

ATTENTION: The document AN383; "Si47XX ANTENNA, SCHEMATIC, LAYOUT, AND DESIGN GUIDELINES"; rev 0.8; page 6; there is the following note: Crystal and digital audio mode cannot be used at the same time. Populate R1 and remove C10, C11, and X1 when using digital audio.

See also: Si47XX PROGRAMINGGUIDE; AN332 (REV 1.0); page 196.; Si47XX ANTENNA, SCHEMATIC, LAYOUT, AND DESIGN GUIDELINES; AN383; rev 0.8; page 6

Parameters

uint16_t DOSR Digital Output Sample Rate(32–48 ksps .0 to disable digital audio output).

◆ setVolume()

void SI4735::setVolume ( uint8_t volume )

Sets volume level (0 to 63)

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 62, 123, 170, 173 and 204

Parameters

uint8_t volume (domain: 0 - 63)

◆ setAudioMute()

void SI4735::setAudioMute ( bool off )

Sets the audio on or off.

Useful to mute the audio output of the SI47XX device. This function does not work to reduce the pop in the speaker at start the system up.

If you want to remove the loud click or pop in the speaker at start, power down and power up commands, use setHardwareAudioMute with a external mute circuit.