Functions
bool	SI4735::getSignalQualityInterrupt ()
	Get the Signal Quality Interrupt status.

bool	SI4735::getRadioDataSystemInterrupt ()
	Get the Radio Data System (RDS) Interrupt status.

bool	SI4735::getTuneCompleteTriggered ()
	Get the Tune Complete status.

bool	SI4735::getStatusError ()
	Get the Status Error.

bool	SI4735::getStatusCTS ()
	Gets the Error flag Clear to Send.

bool	SI4735::getACFIndicator ()
	Returns true if the AFC rails (AFC Rail Indicator).

bool	SI4735::getBandLimit ()
	Returns true if a seek hit the band limit.

bool	SI4735::getStatusValid ()
	Gets the channel status.

uint8_t	SI4735::getReceivedSignalStrengthIndicator ()
	Returns the value of Received Signal Strength Indicator (dBμV).

uint8_t	SI4735::getStatusSNR ()
	Gets the SNR metric when tune is complete (dB)

uint8_t	SI4735::getStatusMULT ()
	Get the Status the M U L T.

bool	SI4735::isAgcEnabled ()
	Checks if the AGC is enabled.

uint8_t	SI4735::getAgcGainIndex ()
	Gets the current AGC gain index.

void	SI4735::setAGC (uint8_t AGCDIS, uint8_t AGCIDX)
	Automatic Gain Control setup (alternative name for setAutomaticGainControl )

uint8_t	SI4735::getCurrentRSSI ()
	Get the current receive signal strength (0–127 dBμV)

uint8_t	SI4735::getCurrentSNR ()
	Gets the current SNR metric (0–127 dB).

bool	SI4735::getCurrentRssiDetectLow ()
	Checks if RSSI detected is LOW.

bool	SI4735::getCurrentRssiDetectHigh ()
	Checks if RSSI detected is high.

bool	SI4735::getCurrentSnrDetectLow ()
	Checks if SNR detect is low.

bool	SI4735::getCurrentSnrDetectHigh ()
	Checks if SNR detect is high.

bool	SI4735::getCurrentValidChannel ()
	Checks if the current channel is valid.

bool	SI4735::getCurrentAfcRailIndicator ()
	AFC Rail Indicator.

bool	SI4735::getCurrentSoftMuteIndicator ()
	Soft Mute Indicator.

uint8_t	SI4735::getCurrentStereoBlend ()
	Gets the value of the amount of stereo blend in % (100 = full stereo, 0 = full mono).

bool	SI4735::getCurrentPilot ()
	Checks the current pilot.

uint8_t	SI4735::getCurrentMultipath ()
	Gets the current Multipath.

uint8_t	SI4735::getCurrentSignedFrequencyOffset ()
	Gets the Signed frequency offset (kHz).

bool	SI4735::getCurrentMultipathDetectLow ()
	Get Multipath Detect Low.

bool	SI4735::getCurrentMultipathDetectHigh ()
	Gets the Current Multipath Detect High.

bool	SI4735::getCurrentBlendDetectInterrupt ()
	Gets the Current Blend Detect Interrupt.

void	SI4735::setFMDeEmphasis (uint8_t parameter)
	Sets the FM Receive de-emphasis to 50 or 75 μs.

void	SI4735::setFmSoftMuteMaxAttenuation (uint8_t smattn=0)
	Sets the Fm Soft Mute Max Attenuation.

void	SI4735::setAMDeEmphasis (uint8_t parameter)
	Sets the AM Receive de-emphasis to 50 or disable.

void	SI4735::setAMSoftMuteSlop (uint8_t parameter)
	Sets the AM attenuation slope during soft mute.

void	SI4735::setAMSoftMuteRate (uint8_t parameter)
	Sets the attack and decay rates when entering or leaving soft mute.

void	SI4735::setAMSoftMuteSnrThreshold (uint8_t parameter)
	Sets the SNR threshold to engage soft mute.

void	SI4735::setAMSoftMuteReleaseRate (uint8_t parameter)
	Sets the soft mute release rate.

void	SI4735::setAMSoftMuteAttackRate (uint16_t parameter)
	Sets the soft mute attack rate.

void	SI4735::setAmAgcAttackRate (uint16_t parameter)
	Sets the AGC attack rate.

void	SI4735::setAmAgcReleaseRate (uint16_t parameter)
	Sets the AGC release rate.

void	SI4735::setAMFrontEndAgcControl (uint8_t MIN_GAIN_INDEX, uint8_t ATTN_BACKUP)
	Adjusts the AM AGC for external front-end attenuator and external front-end cascode LNA.

bool	SI4735::isCurrentTuneAM ()
	Returns true if the current function is AM (AM_TUNE_FREQ).

bool	SI4735::isCurrentTuneSSB ()
	Returns true if the current function is SSB (SSB_TUNE_FREQ).

uint8_t	SI4735::getTuneFrequecyFast ()
	Returns the FAST tuning status.

void	SI4735::setTuneFrequencyFast (uint8_t FAST)
	Sets the FAST Tuning.

uint8_t	SI4735::getTuneFrequecyFreeze ()
	Returns the FREEZE status.

void	SI4735::setTuneFrequencyFreze (uint8_t FREEZE)
	Sets Freeze Metrics During Alternate Frequency Jum.

void	SI4735::setFrequencyUp ()
	Set the FrequencyUp.

void	SI4735::setFrequencyDown ()
	Set the Frequency Down.

void	SI4735::setMaxSeekTime (long time_in_ms)
	Sets the maximum time in milliseconds for seeking. The default value is 8000ms (8s).

void	SI4735::seekStationUp ()
	Search for the next station.

void	SI4735::seekStationDown ()
	Search the previous station.

void	SI4735::setSeekAmSrnThreshold (uint16_t value)
	Set the Seek Am Srn Threshold object.

void	SI4735::setSeekAmSNRThreshold (uint16_t value)
	Sets the SNR threshold for a valid AM Seek/Tune.

void	SI4735::setSeekFmSrnThreshold (uint16_t value)
	Set the Seek Fm Srn Threshold object.

void	SI4735::setSeekFmSNRThreshold (uint16_t value)
	Sets the SNR threshold for a valid FM Seek/Tune.

void	SI4735::setMaxDelaySetFrequency (uint16_t ms)
	Set the Max Delay after Set Frequency.

void	SI4735::setFrequencyStep (uint16_t step)
	Sets the current step value.

uint16_t	SI4735::getCurrentFrequency ()
	Gets the current frequency saved in memory.

void	SI4735::getStatus ()
	Gets the current status of the Si47XX (AM, FM or SSB)

void	SI4735::setTuneFrequencyAntennaCapacitor (uint16_t capacitor)
	Selects the tuning capacitor value.

void	SI4735::setFrequency (uint16_t)
	Set the frequency to the corrent function of the Si4735 (FM, AM or SSB)

void	SI4735::frequencyUp ()
	Increments the current frequency on current band/function by using the current step.

void	SI4735::frequencyDown ()
	Decrements the current frequency on current band/function by using the current step.

void	SI4735::setAM ()
	Sets the radio to AM function. It means: LW MW and SW.

void	SI4735::setFM ()
	Sets the radio to FM function.

void	SI4735::setAM (uint16_t fromFreq, uint16_t toFreq, uint16_t intialFreq, uint16_t step)
	Sets the radio to AM (LW/MW/SW) function.

void	SI4735::setFM (uint16_t fromFreq, uint16_t toFreq, uint16_t initialFreq, uint16_t step)
	Sets the radio to FM function.

void	SI4735::setBandwidth (uint8_t AMCHFLT, uint8_t AMPLFLT)
	Selects the bandwidth of the channel filter for AM reception.

uint16_t	SI4735::getFrequency (void)
	Gets the current frequency of the Si4735 (AM or FM)

void	SI4735::getStatus (uint8_t, uint8_t)
	Gets the current status of the Si4735 (AM or FM)

void	SI4735::getAutomaticGainControl ()
	Queries Automatic Gain Control STATUS.

void	SI4735::setAutomaticGainControl (uint8_t AGCDIS, uint8_t AGCIDX)
	Automatic Gain Control setup.

void	SI4735::setAvcAmMaxGain (uint8_t gain=90)
	Sets the maximum gain for automatic volume control.

void	SI4735::getCurrentReceivedSignalQuality (uint8_t INTACK)
	Queries the status of the Received Signal Quality (RSQ) of the current channel.

void	SI4735::getCurrentReceivedSignalQuality (void)
	Queries the status of the Received Signal Quality (RSQ) of the current channel (FM_RSQ_STATUS)

void	SI4735::seekStation (uint8_t SEEKUP, uint8_t WRAP)
	Look for a station (Automatic tune)

void	SI4735::seekNextStation ()
	Search for the next station.

void	SI4735::seekPreviousStation ()
	Search the previous station.

void	SI4735::seekStationProgress (void(*showFunc)(uint16_t f), uint8_t up_down)
	Seeks a station up or down.

void	SI4735::seekStationProgress (void(showFunc)(uint16_t f), bool(stopSeking)(), uint8_t up_down)
	Seeks a station up or down.

void	SI4735::setSeekAmLimits (uint16_t bottom, uint16_t top)
	Sets the bottom frequency and top frequency of the AM band for seek. Default is 520 to 1710.

void	SI4735::setSeekFmLimits (uint16_t bottom, uint16_t top)
	Sets the bottom frequency and top frequency of the FM band for seek. Default is 8750 to 10790.

void	SI4735::setSeekAmSpacing (uint16_t spacing)
	Selects frequency spacingfor AM seek. Default is 10 kHz spacing.

void	SI4735::setSeekFmSpacing (uint16_t spacing)
	Selects frequency spacingfor FM seek. Default is 100 kHz (value 10) spacing. There are only 3 valid values: 5, 10, and 20.

void	SI4735::setSeekAmRssiThreshold (uint16_t value)
	Sets the RSSI threshold for a valid AM Seek/Tune.

void	SI4735::setSeekFmRssiThreshold (uint16_t value)
	Sets the RSSI threshold for a valid FM Seek/Tune.

Detailed Description

Function Documentation

◆ getSignalQualityInterrupt()

bool SI4735::getSignalQualityInterrupt ( )

inline

Get the Signal Quality Interrupt status.

STATUS RESPONSE Set of methods to get current status information. Call them after getStatus or getFrequency or seekStation

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 63; Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 63

Returns: RDSINT status

◆ getRadioDataSystemInterrupt()

bool SI4735::getRadioDataSystemInterrupt ( )

inline

Get the Radio Data System (RDS) Interrupt status.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 63

Returns: RDSINT status

◆ getTuneCompleteTriggered()

bool SI4735::getTuneCompleteTriggered ( )

inline

Get the Tune Complete status.

Seek/Tune Complete Interrupt; 1 = Tune complete has been triggered.

Returns: STCINT status

◆ getStatusError()

bool SI4735::getStatusError ( )

inline

Get the Status Error.

Return the Error flag (true or false) of status of the least Tune or Seek

Returns: Error flag

◆ getStatusCTS()

bool SI4735::getStatusCTS ( )

inline

Gets the Error flag Clear to Send.

Returns: CTS

◆ getACFIndicator()

bool SI4735::getACFIndicator ( )

inline

Returns true if the AFC rails (AFC Rail Indicator).

Returns: true

◆ getBandLimit()

bool SI4735::getBandLimit ( )

inline

Returns true if a seek hit the band limit.

(WRAP = 0 in FM_START_SEEK) or wrapped to the original frequency(WRAP = 1).

Returns: BLTF

◆ getStatusValid()

bool SI4735::getStatusValid ( )

inline

Gets the channel status.

Returns true if the channel is currently valid as determined by the seek/tune properties (0x1403, 0x1404, 0x1108)

Returns: true; false

◆ getReceivedSignalStrengthIndicator()

uint8_t SI4735::getReceivedSignalStrengthIndicator ( )

inline

Returns the value of Received Signal Strength Indicator (dBμV).

Returns: uint8_t

◆ getStatusSNR()

uint8_t SI4735::getStatusSNR ( )

inline

Gets the SNR metric when tune is complete (dB)

Returns the value of the SNR metric when tune is complete (dB).

Returns: uint8_t

◆ getStatusMULT()

uint8_t SI4735::getStatusMULT ( )

inline

Get the Status the M U L T.

Returns the value containing the multipath metric when tune is complete.

Returns: uint8_t

◆ isAgcEnabled()

bool SI4735::isAgcEnabled ( )

inline

Checks if the AGC is enabled.

Returns: true if the AGC is enabled

◆ getAgcGainIndex()

uint8_t SI4735::getAgcGainIndex ( )

inline

Gets the current AGC gain index.

Returns: uint8_t The current AGC gain index.

◆ setAGC()

void SI4735::setAGC	(	uint8_t	AGCDIS,
		uint8_t	AGCIDX
	)

inline

Automatic Gain Control setup (alternative name for setAutomaticGainControl )

If FM, overrides AGC setting by disabling the AGC and forcing the LNA to have a certain gain that ranges between 0 (minimum attenuation) and 26 (maximum attenuation).

If AM/SSB, Overrides the AGC setting by disabling the AGC and forcing the gain index that ranges between 0 (minimum attenuation) and 37+ATTN_BACKUP (maximum attenuation).

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); For FM page 81; for AM page 143; setAutomaticGainControl

Parameters

uint8_t	AGCDIS This param selects whether the AGC is enabled or disabled (0 = AGC enabled; 1 = AGC disabled);
uint8_t	AGCIDX AGC Index (0 = Minimum attenuation (max gain); 1 – 36 = Intermediate attenuation); if >greater than 36 - Maximum attenuation (min gain) ).

◆ getCurrentRSSI()

uint8_t SI4735::getCurrentRSSI ( )

inline

Get the current receive signal strength (0–127 dBμV)

Returns: uint8_t a value between 0 to 127

◆ getCurrentSNR()

uint8_t SI4735::getCurrentSNR ( )

inline

Gets the current SNR metric (0–127 dB).

Returns: uint8_t SNR value in dB (0-127)

◆ getCurrentRssiDetectLow()

bool SI4735::getCurrentRssiDetectLow ( )

inline

Checks if RSSI detected is LOW.

Returns: true if RSSI is low

◆ getCurrentRssiDetectHigh()

bool SI4735::getCurrentRssiDetectHigh ( )

inline

Checks if RSSI detected is high.

Returns: true if RSSI detected is high

◆ getCurrentSnrDetectLow()

bool SI4735::getCurrentSnrDetectLow ( )

inline

Checks if SNR detect is low.

Returns: true if SNR detected is low

◆ getCurrentSnrDetectHigh()

bool SI4735::getCurrentSnrDetectHigh ( )

inline

Checks if SNR detect is high.

Returns: true if SNR detect is high

◆ getCurrentValidChannel()

bool SI4735::getCurrentValidChannel ( )

inline

Checks if the current channel is valid.

Returns: true if the current channel is valid

◆ getCurrentAfcRailIndicator()

bool SI4735::getCurrentAfcRailIndicator ( )

inline

AFC Rail Indicator.

Returns: true or false

◆ getCurrentSoftMuteIndicator()

bool SI4735::getCurrentSoftMuteIndicator ( )

inline

Soft Mute Indicator.

Indicates soft mute is engaged.

Returns: true if soft mute indicates is engaged.

◆ getCurrentStereoBlend()

uint8_t SI4735::getCurrentStereoBlend ( )

inline

Gets the value of the amount of stereo blend in % (100 = full stereo, 0 = full mono).

Returns: uint8_t value (0 to 100)

◆ getCurrentPilot()

bool SI4735::getCurrentPilot ( )

inline

Checks the current pilot.

Indicates stereo pilot presence.

Returns: true if stereo pilot presence has detected

◆ getCurrentMultipath()

uint8_t SI4735::getCurrentMultipath ( )

inline

Gets the current Multipath.

Contains the current multipath metric. (0 = no multipath; 100 = full multipath)

Returns: uint8_t value (0 to 100)

◆ getCurrentSignedFrequencyOffset()

uint8_t SI4735::getCurrentSignedFrequencyOffset ( )

inline

Gets the Signed frequency offset (kHz).

Returns: uint8_t

◆ getCurrentMultipathDetectLow()

bool SI4735::getCurrentMultipathDetectLow ( )

inline

Get Multipath Detect Low.

Returns: true; false

◆ getCurrentMultipathDetectHigh()

bool SI4735::getCurrentMultipathDetectHigh ( )

inline

Gets the Current Multipath Detect High.

Returns: true; false

◆ getCurrentBlendDetectInterrupt()

bool SI4735::getCurrentBlendDetectInterrupt ( )

inline

Gets the Current Blend Detect Interrupt.

Returns: true; false

◆ setFMDeEmphasis()

void SI4735::setFMDeEmphasis ( uint8_t parameter )

inline

Sets the FM Receive de-emphasis to 50 or 75 μs.

valid parameters are 1 = 50 μs. Usedin Europe, Australia, Japan; 2 = 75 μs. Used in USA (default)

Parameters

parameter 1 or 2 (default 1 - USA)

◆ setFmSoftMuteMaxAttenuation()

void SI4735::setFmSoftMuteMaxAttenuation ( uint8_t smattn = 0 )

inline

Sets the Fm Soft Mute Max Attenuation.

This function can be useful to disable Soft Mute on FM mode. The value 0 disable soft mute.

Specified in units of dB. Default maximum attenuation is 8 dB. It works for AM and SSB.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 97.

Parameters

smattn Maximum attenuation to apply when in soft mute

◆ setAMDeEmphasis()

void SI4735::setAMDeEmphasis ( uint8_t parameter )

inline

Sets the AM Receive de-emphasis to 50 or disable.

valid parameters are 1 = 50 μs. Usedin urope, Australia, Japan; 2 = 75 μs. Used in USA (default)

Parameters

parameter 1 = enable or 0 = disable

◆ setAMSoftMuteSlop()

void SI4735::setAMSoftMuteSlop ( uint8_t parameter )

inline

Sets the AM attenuation slope during soft mute.

Configures attenuation slope during soft mute in dB attenuation per dB SNR below the soft mute SNR threshold.

Soft mute attenuation is the minimum of SMSLOPEx(SMTHR–SNR) and SMATTN.

The default slope is 1 dB/dB for AMRX component 5.0 or later and 2 dB/dB for AMRX component 3.0 or earlier.

See also: setAmSoftMuteMaxAttenuation; Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0);

Parameters

parameter the valid values are 1–5 (default 1).

◆ setAMSoftMuteRate()

void SI4735::setAMSoftMuteRate ( uint8_t parameter )

inline

Sets the attack and decay rates when entering or leaving soft mute.

The value specified is multiplied by 4.35 dB/s to come up with the actual attack rate

The default rate is 278 dB/s.

See also: setAmSoftMuteMaxAttenuation; Si47XX PRORAMMING GUIDE; AN332 (REV 1.0);

Parameters

parameter The valid values are 1-255 ( Default is ~64 - [64 x 4.35 = 278] )

◆ setAMSoftMuteSnrThreshold()

void SI4735::setAMSoftMuteSnrThreshold ( uint8_t parameter )

inline

Sets the SNR threshold to engage soft mute.

Whenever the SNR for a tuned frequency drops below this threshold the AM reception will go in soft mute,

provided soft mute max attenuation property is non-zero. The default value is 8dB

See also: setAmSoftMuteMxAttenuation; Si47XX PROAMMING GUIDE; AN332 (REV 1.0);

Parameters

parameter 0-63 (default is 8)

◆ setAMSoftMuteReleaseRate()

void SI4735::setAMSoftMuteReleaseRate ( uint8_t parameter )

inline

Sets the soft mute release rate.

Smaller values provide slower release and larger values provide faster release. The default is 8192 (approximately 8000 dB/s).

See also: setAmSoftMuteMxAttenuation; Si47XX PROAMMING GUIDE; AN332 (REV 1.0);

Parameters

parameter 1–32767

◆ setAMSoftMuteAttackRate()

void SI4735::setAMSoftMuteAttackRate ( uint16_t parameter )

inline

Sets the soft mute attack rate.

Smaller values provide slower attack and larger values provide faster attack.

See also: setAmSoftMuteMxAttenuation; Si47XX PROAMMING GUIDE; AN332 (REV 1.0);

Parameters

parameter 1–32767 (The default is 8192 (approximately 8000 dB/s)

◆ setAmAgcAttackRate()

void SI4735::setAmAgcAttackRate ( uint16_t parameter )

inline

Sets the AGC attack rate.

Large values provide slower attack, and smaller values provide faster attack..

See also: setAmAgcAttackRate; Si47XX PROAMMING GUIDE; AN332 (REV 1.2); page 167

Parameters

parameter Range: 4–248 (The default is 0x04)

◆ setAmAgcReleaseRate()

void SI4735::setAmAgcReleaseRate ( uint16_t parameter )

inline

Sets the AGC release rate.

Larger values provide slower release, and smaller values provide faster release.

See also: setAmAgcReleaseRate; Si47XX PROAMMING GUIDE; AN332 (REV 1.2); page 168

Parameters

parameter Range: 4–248 (The default is 0x8C)

◆ setAMFrontEndAgcControl()

void SI4735::setAMFrontEndAgcControl	(	uint8_t	MIN_GAIN_INDEX,
		uint8_t	ATTN_BACKUP
	)

inline

Adjusts the AM AGC for external front-end attenuator and external front-end cascode LNA.

This property contains two fields: MIN_GAIN_INDEX and ATTN_BACKUP.

MIN_GAIN_INDEX impacts sensitivity and U/D performance. Lower values improve sensitivity, but degrade

far away blocker U/D performance.

Higher values degrade sensitivity, but improve U/D. With MIN_GAIN_INDEX=19 and Si4743 EVB reference

design, the Si474x provides sensitivity of 28dBuV typical and U/D exceeding 55dB on far away blockers.

With MIN_GAIN_INDEX=24, the Si474x provides sensitivity of 34dBuV typical and U/D approaching 70dB on

far away blockers.

See also: Si47XX PROAMMING GUIDE; AN332 (REV 1.0); page 168

Parameters

MIN_GAIN_INDEX	Values below 19 have minimal sensitivity improvement; Higher values degrade sensitivity, but improve U/D.
ATTN_BACKUP	???

◆ isCurrentTuneAM()

bool SI4735::isCurrentTuneAM ( )

inline

Returns true if the current function is AM (AM_TUNE_FREQ).

Returns: true if the current function is AM (AM_TUNE_FREQ).

◆ isCurrentTuneSSB()

bool SI4735::isCurrentTuneSSB ( )

inline

Returns true if the current function is SSB (SSB_TUNE_FREQ).

Returns: true if the current function is SSB (SSB_TUNE_FREQ).

◆ getTuneFrequecyFast()

uint8_t SI4735::getTuneFrequecyFast ( )

inline

Returns the FAST tuning status.

@retrn uint8_t

◆ setTuneFrequencyFast()

void SI4735::setTuneFrequencyFast ( uint8_t FAST )

inline

Sets the FAST Tuning.

If set, excutes fast and invalidated tune. Theune status will not be accurate

Parameters

FAST

◆ getTuneFrequecyFreeze()

uint8_t SI4735::getTuneFrequecyFreeze ( )

inline

Returns the FREEZE status.

Returns: unt8_t

◆ setTuneFrequencyFreze()

void SI4735::setTuneFrequencyFreze ( uint8_t FREEZE )

inline

Sets Freeze Metrics During Alternate Frequency Jum.

Only on FM mode

Parameters

FREEZE

◆ setFrequencyUp()

void SI4735::setFrequencyUp ( )

inline

Set the FrequencyUp.

Same frequencyUp

See also: frequencyUp

References SI4735::frequencyUp().

◆ setFrequencyDown()

void SI4735::setFrequencyDown ( )

inline

Set the Frequency Down.

same frequencyDown

See also: frequencyDown

References SI4735::frequencyDown().

◆ setMaxSeekTime()

void SI4735::setMaxSeekTime ( long time_in_ms )

inline

Sets the maximum time in milliseconds for seeking. The default value is 8000ms (8s).

Depending on the bandwidth, your reception conditions or step configuration, the seek process can take a long time.

This function sets a time limit for seeking process and back the control to the system if the time runs out.

Parameters

time_in_ms time in milliseconds.

References SI4735::maxSeekTime.

◆ seekStationUp()

void SI4735::seekStationUp ( )

inline

Search for the next station.

Seek a station up. Stop when a station is found or the frequency has reached the upper limit

See also: seekStation, seekStationProgress, setSeekAmLimits setSeekFmLimits; Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 124, 137, 139, 278

◆ seekStationDown()

void SI4735::seekStationDown ( )

inline

Search the previous station.

Seek a station Down. Stop when a station is found or the frequency has reached the lower limit

See also: seekStation, seekStationProgress, setSeekAmLimits, setSeekFmLimits; Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 124, 137, 139, 278

◆ setSeekAmSrnThreshold()

void SI4735::setSeekAmSrnThreshold ( uint16_t value )

inline

Set the Seek Am Srn Threshold object.

Deprecated:: Use setSeekAmSNRThreshold instead.

See also: setSeekAmSNRThreshold

Parameters

value

◆ setSeekAmSNRThreshold()

void SI4735::setSeekAmSNRThreshold ( uint16_t value )

inline

Sets the SNR threshold for a valid AM Seek/Tune.

If the value is zero then SNR threshold is not considered when doing a seek. Default value is 5 dB.

See also: Si47XX PROGRAMMING GUIDE; (REV 1.0); page 127

◆ setSeekFmSrnThreshold()

void SI4735::setSeekFmSrnThreshold ( uint16_t value )

inline

Set the Seek Fm Srn Threshold object.

Deprecated:: Use setSeekFmSNRThreshold instead.

See also: setSeekFmSNRThreshold

Parameters

value

◆ setSeekFmSNRThreshold()

void SI4735::setSeekFmSNRThreshold ( uint16_t value )

inline

Sets the SNR threshold for a valid FM Seek/Tune.

SNR Threshold which determines if a valid channel has been found during Seek/Tune. Specified in units of dB in 1 dB steps (0–127). Default is 3 dB

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 102

Parameters

value between 0 and 127.

◆ setMaxDelaySetFrequency()

void SI4735::setMaxDelaySetFrequency ( uint16_t ms )

inline

Set the Max Delay after Set Frequency.

After the set frequency command, the system need a time to get ready to the next set frequency (default value 30ms).

Why the waitToSend() does not work in this case? No idea for while!

A low value makes the getFrequency command inaccurate.

See also: MAX_DELAY_AFTER_POWERUP

Parameters

ms

◆ setFrequencyStep()

void SI4735::setFrequencyStep ( uint16_t step )

inline

Sets the current step value.

This function does not check the limits of the current band. Do not take a step that will extend past the limit of the band.

Example:

setFM(6400,10800,10390,10);
setFrequencyStep(100); // the step will be 1MHz (you are using FM mode)
.
.
.
setAM(7000,7600,7100,5);
setFrequencyStep(1); // the step will be 1kHz (you are usin AM or SSB mode)

See also: setFM(); setAM(); setSSB()

Parameters

step	if you are using FM, 10 means 100kHz. If you are using AM 10 means 10kHz For AM, 1 (1kHz) to 1000 (1MHz) are valid values. For FM 5 (50kHz), 10 (100kHz) and 100 (1MHz) are valid values.

◆ getCurrentFrequency()

uint16_t SI4735::getCurrentFrequency ( )

inline

Gets the current frequency saved in memory.

Unlike getFrequency, this method gets the current frequency recorded after the last setFrequency command.

This method avoids bus traffic and CI processing.

However, you can not get others status information like RSSI.

See also: getFrequency()

◆ getStatus() [1/2]

void SI4735::getStatus ( )

inline

Gets the current status of the Si47XX (AM, FM or SSB)

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 73 (FM) and 139 (AM)

References SI4735::getStatus().

Referenced by SI4735::getFrequency(), and SI4735::getStatus().

◆ setTuneFrequencyAntennaCapacitor()

void SI4735::setTuneFrequencyAntennaCapacitor ( uint16_t capacitor )

Selects the tuning capacitor value.

On FM mode, the Antenna Tuning Capacitor is valid only when using TXO/LPI pin as the antenna input. This selects the value of the antenna tuning capacitor manually, or automatically if set to zero. The valid range is 0 to 191. Automatic capacitor tuning is recommended. For example, if the varactor is set to a value of 5 manually, when read back the value will be 1.

on AM mode, If the value is set to anything other than 0, the tuning capacitance is manually set as 95 fF x ANTCAP + 7 pF. ANTCAP manual range is 1–6143. Automatic capacitor tuning is recommended. In SW mode, ANTCAPH[15:8] (high byte) needs to be set to 0 and ANTCAPL[7:0] (low byte) needs to be set to 1.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 71 and 136

Parameters

capacitor If zero, the tuning capacitor value is selected automatically. If the value is set to anything other than 0: AM - the tuning capacitance is manually set as 95 fF x ANTCAP + 7 pF. ANTCAP manual range is 1–6143; FM - the valid range is 0 to 191. According to Silicon Labs, automatic capacitor tuning is recommended (value 0).

◆ setFrequency()

void SI4735::setFrequency ( uint16_t freq )

Set the frequency to the corrent function of the Si4735 (FM, AM or SSB)

You have to call setup or setPowerUp before call setFrequency.

See also: maxDelaySetFrequency(); MAX_DELAY_AFTER_SET_FREQUENCY; Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 70, 135; AN332 REV 0.8 UNIVERSAL PROGRAMMING GUIDE; page 13

Parameters

uint16_t freq is the frequency to change. For example, FM => 10390 = 103.9 MHz; AM => 810 = 810 kHz.

References SI4735::waitToSend().

◆ frequencyUp()

void SI4735::frequencyUp ( )

Increments the current frequency on current band/function by using the current step.

See also: setFrequencyStep()

Referenced by SI4735::setFrequencyUp().

◆ frequencyDown()

void SI4735::frequencyDown ( )

Decrements the current frequency on current band/function by using the current step.

See also: setFrequencyStep()

Referenced by SI4735::setFrequencyDown().

◆ setAM() [1/2]

void SI4735::setAM ( )

Sets the radio to AM function. It means: LW MW and SW.

Todo:: Adjust the power up parameters

Define the band range you want to use for the AM mode.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 129.

References SI4735::powerDown(), and SI4735::radioPowerUp().

Referenced by SI4735::setAM().

◆ setFM() [1/2]

void SI4735::setFM ( )

Sets the radio to FM function.

Todo:: Adjust the power up parameters

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 64.

References SI4735::disableFmDebug(), SI4735::powerDown(), and SI4735::radioPowerUp().

Referenced by SI4735::setFM().

◆ setAM() [2/2]

void SI4735::setAM	(	uint16_t	fromFreq,
		uint16_t	toFreq,
		uint16_t	initialFreq,
		uint16_t	step
	)

Sets the radio to AM (LW/MW/SW) function.

The example below sets the band from 550kHz to 1750kHz on AM mode. The band will start on 810kHz and step is 10kHz.

si4735.setAM(520, 1750, 810, 10);

See also: setFM(); setSSB()

Parameters

fromFreq	minimum frequency for the band
toFreq	maximum frequency for the band
initialFreq	initial frequency
step	step used to go to the next channel

References SI4735::setAM().

◆ setFM() [2/2]

void SI4735::setFM	(	uint16_t	fromFreq,
		uint16_t	toFreq,
		uint16_t	initialFreq,
		uint16_t	step
	)

Sets the radio to FM function.

Defines the band range you want to use for the FM mode.

The example below sets the band from 64MHz to 108MHzkHz on FM mode. The band will start on 103.9MHz and step is 100kHz. On FM mode, the step 10 means 100kHz. If you want a 1MHz step, use 100.

si4735.setFM(6400, 10800, 10390, 10);

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 70; setFM(); setFrequencyStep()

Parameters

fromFreq	minimum frequency for the band
toFreq	maximum frequency for the band
initialFreq	initial frequency (default frequency)
step	step used to go to the next channel

References SI4735::setFM().

◆ setBandwidth()

void SI4735::setBandwidth	(	uint8_t	AMCHFLT,
		uint8_t	AMPLFLT
	)

Selects the bandwidth of the channel filter for AM reception.

The choices are 6, 4, 3, 2, 2.5, 1.8, or 1 (kHz). The default bandwidth is 2 kHz. It works only in AM / SSB (LW/MW/SW)

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 125, 151, 277, 181.

Parameters

AMCHFLT	the choices are: 0 = 6 kHz Bandwidth 1 = 4 kHz Bandwidth 2 = 3 kHz Bandwidth 3 = 2 kHz Bandwidth 4 = 1 kHz Bandwidth 5 = 1.8 kHz Bandwidth 6 = 2.5 kHz Bandwidth, gradual roll off 7–15 = Reserved (Do not use).
AMPLFLT	Enables the AM Power Line Noise Rejection Filter.

References SI4735::waitToSend().

◆ getFrequency()

uint16_t SI4735::getFrequency ( void )

Gets the current frequency of the Si4735 (AM or FM)

The method status do it an more. See getStatus below.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 73 (FM) and 139 (AM)

References SI4735::getStatus().

◆ getStatus() [2/2]

void SI4735::getStatus	(	uint8_t	INTACK,
		uint8_t	CANCEL
	)

Gets the current status of the Si4735 (AM or FM)

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 73 (FM) and 139 (AM)

Parameters

uint8_t	INTACK Seek/Tune Interrupt Clear. If set, clears the seek/tune complete interrupt status indicator;
uint8_t	CANCEL Cancel seek. If set, aborts a seek currently in progress;

References SI4735::waitToSend().

◆ getAutomaticGainControl()

void SI4735::getAutomaticGainControl ( )

Queries Automatic Gain Control STATUS.

After call this method, you can call isAgcEnabled to know the AGC status and getAgcGainIndex to know the gain index value.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); For FM page 80; for AM page 142.; AN332 REV 0.8 Universal Programming Guide Amendment for SI4735-D60 SSB and NBFM patches; page 18.

References SI4735::waitToSend().

◆ setAutomaticGainControl()

void SI4735::setAutomaticGainControl	(	uint8_t	AGCDIS,
		uint8_t	AGCIDX
	)

Automatic Gain Control setup.

If FM, overrides AGC setting by disabling the AGC and forcing the LNA to have a certain gain that ranges between 0 (minimum attenuation) and 26 (maximum attenuation).

If AM/SSB, Overrides the AGC setting by disabling the AGC and forcing the gain index that ranges between 0 (minimum attenuation) and 37+ATTN_BACKUP (maximum attenuation).

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); For FM page 81; for AM page 143

Parameters

uint8_t	AGCDIS This param selects whether the AGC is enabled or disabled (0 = AGC enabled; 1 = AGC disabled);
uint8_t	AGCIDX AGC Index (0 = Minimum attenuation (max gain); 1 – 36 = Intermediate attenuation); if >greater than 36 - Maximum attenuation (min gain) ).

References SI4735::waitToSend().

◆ setAvcAmMaxGain()

void SI4735::setAvcAmMaxGain ( uint8_t gain = 90 )

Sets the maximum gain for automatic volume control.

Sets the gain for automatic volume control.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 152; setAvcAmMaxGain()

Parameters

uint8_t gain Select a value between 12 and 90. Defaul value 48dB.

◆ getCurrentReceivedSignalQuality() [1/2]

void SI4735::getCurrentReceivedSignalQuality ( uint8_t INTACK )

Queries the status of the Received Signal Quality (RSQ) of the current channel.

This method sould be called berore call getCurrentRSSI(), getCurrentSNR() etc. Command FM_RSQ_STATUS

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 75 and 141

Parameters

INTACK Interrupt Acknowledge. 0 = Interrupt status preserved; 1 = Clears RSQINT, BLENDINT, SNRHINT, SNRLINT, RSSIHINT, RSSILINT, MULTHINT, MULTLINT.

References SI4735::waitToSend().

◆ getCurrentReceivedSignalQuality() [2/2]

void SI4735::getCurrentReceivedSignalQuality ( void )

Queries the status of the Received Signal Quality (RSQ) of the current channel (FM_RSQ_STATUS)

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 75 and 141

Parameters

INTACK Interrupt Acknowledge. 0 = Interrupt status preserved; 1 = Clears RSQINT, BLENDINT, SNRHINT, SNRLINT, RSSIHINT, RSSILINT, MULTHINT, MULTLINT.

References SI4735::getCurrentReceivedSignalQuality().

Referenced by SI4735::getCurrentReceivedSignalQuality().

◆ seekStation()

void SI4735::seekStation	(	uint8_t	SEEKUP,
		uint8_t	WRAP
	)

Look for a station (Automatic tune)

Starts a seek process for a channel that meets the RSSI and SNR criteria for AM.

This function does not work on SSB mode.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 55, 72, 125 and 137

Parameters

SEEKUP	Seek Up/Down. Determines the direction of the search, either UP = 1, or DOWN = 0.
Wrap/Halt.	Determines whether the seek should Wrap = 1, or Halt = 0 when it hits the band limit.

References SI4735::waitToSend().

◆ seekNextStation()

void SI4735::seekNextStation ( )

Search for the next station.

Like seekStationUp this function goes to a next station.

The main difference is the method used to look for a station.

See also: seekStation, seekStationUp, seekStationDown, seekPreviousStation, seekStationProgress

◆ seekPreviousStation()

void SI4735::seekPreviousStation ( )

Search the previous station.

Like seekStationDown this function goes to a previous station.

The main difference is the method used to look for a station.

See also: seekStation, seekStationUp, seekStationDown, seekPreviousStation, seekStationProgress

◆ seekStationProgress() [1/2]

void SI4735::seekStationProgress	(	void(*)(uint16_t f)	showFunc,
		uint8_t	up_down
	)

Seeks a station up or down.

Seek up or down a station and call a function defined by the developer to show the frequency.

The first parameter of this function is a name of your function that you have to implement to show the current frequency.

If you do not want to show the seeking progress, you can set NULL instead the name of the function.

The code below shows an example using ta function the shows the current frequency on he Serial Monitor. You might want to implement a function that shows the frequency on your display device.

Also, you have to declare the frequency parameter that will be used by the function to show the frequency value.

This function does not work on SSB mode.

void showFrequency( uint16_t freq ) {
   Serial.print(freq);
   Serial.println("MHz ");
}
 
void loop() {
 
 receiver.seekStationProgress(showFrequency,1); // Seek Up
 .
 .
 .
 receiver.seekStationProgress(showFrequency,0); // Seek Down
 
}

See also: seekStation, seekStationUp, seekStationDown, getStatus, setMaxSeekTime

Parameters

showFunc	function that you have to implement to show the frequency during the seeking process. Set NULL if you do not want to show the progress.
up_down	set up_down = 1 for seeking station up; set up_down = 0 for seeking station down

◆ seekStationProgress() [2/2]

void SI4735::seekStationProgress	(	void(*)(uint16_t f)	showFunc,
		bool(*)()	stopSeking,
		uint8_t	up_down
	)

Seeks a station up or down.

Seek up or down a station and call a function defined by the developer to show the frequency and stop seeking process by the user.

The first parameter of this function is a name of your function that you have to implement to show the current frequency.

The second parameter is the name function that will check stop seeking action. Thus function should return true or false and should read a button, encoder or some status to make decision to stop or keep seeking.

If you do not want to show the seeking progress, you can set NULL instead the name of the function.

If you do not want stop seeking checking, you can set NULL instead the name of a function.

The code below shows an example using ta function the shows the current frequency on he Serial Monitor. You might want to implement a function that shows the frequency on your display device.

Also, you have to declare the frequency parameter that will be used by the function to show the frequency value.

This function does not work on SSB mode.

void showFrequency( uint16_t freq ) {
   Serial.print(freq);
   Serial.println("MHz ");
}
 
void loop() {
 
 receiver.seekStationProgress(showFrequency, checkStopSeeking, 1); // Seek Up
 .
 .
 .
 receiver.seekStationProgress(showFrequency, checkStopSeeking, 0); // Seek Down
 
}

See also: seekStation, seekStationUp, seekStationDown, getStatus, setMaxSeekTime

Parameters

showFunc	function that you have to implement to show the frequency during the seeking process. Set NULL if you do not want to show the progress.
stopSeeking	functionthat you have to implement if you want to control the stop seeking action. Useful if you want abort the seek process.
up_down	set up_down = 1 for seeking station up; set up_down = 0 for seeking station down

◆ setSeekAmLimits()

void SI4735::setSeekAmLimits	(	uint16_t	bottom,
		uint16_t	top
	)

Sets the bottom frequency and top frequency of the AM band for seek. Default is 520 to 1710.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 127, 161, and 162

Parameters

uint16_t	bottom - the bottom of the AM (MW/SW) mode for seek
uint16_t	top - the top of the AM (MW/SW) mode for seek

◆ setSeekFmLimits()

void SI4735::setSeekFmLimits	(	uint16_t	bottom,
		uint16_t	top
	)

Sets the bottom frequency and top frequency of the FM band for seek. Default is 8750 to 10790.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 100 and 101

Parameters

uint16_t	bottom - the bottom of the FM(VHF) mode for seek
uint16_t	top - the top of the FM(VHF) mode for seek

◆ setSeekAmSpacing()

void SI4735::setSeekAmSpacing ( uint16_t spacing )

Selects frequency spacingfor AM seek. Default is 10 kHz spacing.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); pages 163, 229 and 283

Parameters

uint16_t spacing - step in kHz

◆ setSeekFmSpacing()

void SI4735::setSeekFmSpacing ( uint16_t spacing )

Selects frequency spacingfor FM seek. Default is 100 kHz (value 10) spacing. There are only 3 valid values: 5, 10, and 20.

Although the guide does not mention it, the value 1 (10 kHz) seems to work better

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 101

Parameters

uint16_t spacing - step in kHz

◆ setSeekAmRssiThreshold()

void SI4735::setSeekAmRssiThreshold ( uint16_t value )

Sets the RSSI threshold for a valid AM Seek/Tune.

If the value is zero then RSSI threshold is not considered when doing a seek. Default value is 25 dBμV.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 127

◆ setSeekFmRssiThreshold()

void SI4735::setSeekFmRssiThreshold ( uint16_t value )

Sets the RSSI threshold for a valid FM Seek/Tune.

RSSI threshold which determines if a valid channel has been found during seek/tune. Specified in units of dBμV in 1 dBμV steps (0–127). Default is 20 dBμV.

See also: Si47XX PROGRAMMING GUIDE; AN332 (REV 1.0); page 102

Functions

Detailed Description

Function Documentation

◆ getSignalQualityInterrupt()

◆ getRadioDataSystemInterrupt()

◆ getTuneCompleteTriggered()

◆ getStatusError()

◆ getStatusCTS()

◆ getACFIndicator()

◆ getBandLimit()

◆ getStatusValid()

◆ getReceivedSignalStrengthIndicator()

◆ getStatusSNR()

◆ getStatusMULT()

◆ isAgcEnabled()

◆ getAgcGainIndex()

◆ setAGC()

◆ getCurrentRSSI()

◆ getCurrentSNR()

◆ getCurrentRssiDetectLow()

◆ getCurrentRssiDetectHigh()

◆ getCurrentSnrDetectLow()

◆ getCurrentSnrDetectHigh()

◆ getCurrentValidChannel()

◆ getCurrentAfcRailIndicator()

◆ getCurrentSoftMuteIndicator()

◆ getCurrentStereoBlend()

◆ getCurrentPilot()

◆ getCurrentMultipath()

◆ getCurrentSignedFrequencyOffset()

◆ getCurrentMultipathDetectLow()

◆ getCurrentMultipathDetectHigh()

◆ getCurrentBlendDetectInterrupt()

◆ setFMDeEmphasis()

◆ setFmSoftMuteMaxAttenuation()

◆ setAMDeEmphasis()

◆ setAMSoftMuteSlop()

◆ setAMSoftMuteRate()

◆ setAMSoftMuteSnrThreshold()

◆ setAMSoftMuteReleaseRate()

◆ setAMSoftMuteAttackRate()

◆ setAmAgcAttackRate()

◆ setAmAgcReleaseRate()

◆ setAMFrontEndAgcControl()

◆ isCurrentTuneAM()

◆ isCurrentTuneSSB()

◆ getTuneFrequecyFast()

◆ setTuneFrequencyFast()

◆ getTuneFrequecyFreeze()

◆ setTuneFrequencyFreze()

◆ setFrequencyUp()

◆ setFrequencyDown()

◆ setMaxSeekTime()

◆ seekStationUp()

◆ seekStationDown()

◆ setSeekAmSrnThreshold()

◆ setSeekAmSNRThreshold()

◆ setSeekFmSrnThreshold()

◆ setSeekFmSNRThreshold()

◆ setMaxDelaySetFrequency()

◆ setFrequencyStep()

◆ getCurrentFrequency()

◆ getStatus() [1/2]

◆ setTuneFrequencyAntennaCapacitor()

◆ setFrequency()

◆ frequencyUp()

◆ frequencyDown()

◆ setAM() [1/2]

◆ setFM() [1/2]

◆ setAM() [2/2]

◆ setFM() [2/2]

◆ setBandwidth()

◆ getFrequency()

◆ getStatus() [2/2]

◆ getAutomaticGainControl()

◆ setAutomaticGainControl()

◆ setAvcAmMaxGain()

◆ getCurrentReceivedSignalQuality() [1/2]

◆ getCurrentReceivedSignalQuality() [2/2]

◆ seekStation()