Public function

Functions
void	fm_cfg_setup (fm_cfg_t *cfg)
	Config Object Initialization function.
FM_RETVAL	fm_init (fm_t *ctx, fm_cfg_t *cfg)
	Initialization function.
void	fm_default_cfg (fm_t *ctx)
	Click Default Configuration function.
void	fm_generic_write (fm_t *ctx, uint16_t *reg_buf)
	Generic write function.
void	fm_generic_read (fm_t *ctx, uint16_t *reg_buf)
	Reading all registers.
void	fm_set_bits (uint16_t *register_buffer, uint16_t register_address, uint16_t bits_mask, uint16_t bits_value)
	Setting bits in specific register on a specific bit location.
uint8_t	fm_set_seek_threshold (fm_t *ctx, uint16_t seek_threshold)
	Setting seek threshold value.
uint8_t	fm_set_volume (fm_t *ctx, uint8_t volume_level)
	Setting volume value.
uint8_t	fm_set_snr_threshold (fm_t *ctx, uint8_t snr_threshold)
	Setting seek SNR threshold value.
uint8_t	fm_set_seek_impulse_detection_threshold (fm_t *ctx, uint8_t impulse_detection_threshold)
	Setting seek impulse detection threshold value.
uint8_t	fm_get_errors_block_a (fm_t *ctx)
	Reading number of errors to be corrected.
uint8_t	fm_get_received_signal_strength_indicator (fm_t *ctx)
	Reading recived strength indicator.
uint8_t	fm_get_errors_block_b (fm_t *ctx)
	Reading number of errors to be corrected.
uint8_t	fm_get_errors_block_c (fm_t *ctx)
	Reading number of errors to be corrected.
uint8_t	fm_get_errors_block_d (fm_t *ctx)
	Reading number of errors to be corrected.
float	fm_get_channel_frequency (fm_t *ctx)
	Calculating current channel frequency.
void	fm_power_up (fm_t *ctx)
	Powering up device.
void	fm_basic_settings (fm_t *ctx)
	Setting basic settings.
void	fm_power_down (fm_t *ctx)
	Powering down device.
uint16_t	fm_get_channel (fm_t *ctx)
	Reading CHANNEL bits.
void	fm_tune_channel (fm_t *ctx, uint16_t channel)
	Setting CHANNEL bits.
uint8_t	fm_tune (fm_t *ctx, float channel_frequency)
	Tunning radio station.
void	fm_end_tune (fm_t *ctx)
	End tunning.
void	fm_seek (fm_t *ctx)
	Start seeking radio station.
void	fm_end_seek (fm_t *ctx)
	End seeking.
uint8_t	fm_volume_up (fm_t *ctx)
	Increasing volume level.
uint8_t	fm_volume_down (fm_t *ctx)
	Decreasing volume level.
void	fm_mute_enable (fm_t *ctx)
	Enable mute.
void	fm_mute_disable (fm_t *ctx)
	Disable mute.
uint8_t	fm_fine_tune_up (fm_t *ctx)
	Fine tunning.
uint8_t	fm_fine_tune_down (fm_t *ctx)
	Fine tunning.
uint8_t	fm_get_int_pin (fm_t *ctx)
	Checking INT pin status.
uint8_t	fm_get_an_pin (fm_t *ctx)
	Checking AN pin status.

Detailed Description

Function Documentation

fm_basic_settings()

void fm_basic_settings

(

fm_t *

ctx

)

Setting basic settings.

Parameters

ctx	Click object.

@description This function sets basic settings to device This function sets optimal settings for device operation in Europe

fm_cfg_setup()

void fm_cfg_setup

(

fm_cfg_t *

cfg

)

Config Object Initialization function.

Parameters

cfg	Click configuration structure.

@description This function initializes click configuration structure to init state.

Note

All used pins will be set to unconnected state.

fm_default_cfg()

void fm_default_cfg

(

fm_t *

ctx

)

Click Default Configuration function.

Parameters

ctx	Click object.

@description This function executes default configuration for Fm click.

fm_end_seek()

void fm_end_seek

(

fm_t *

ctx

)

End seeking.

Parameters

ctx	Click object.

@description This function ends seek by setting SEEK bit LOW This function must be called after fm_seek(); function This function must be executed after seek done interrupt flag This function can be executed before seek done interrupt flag

fm_end_tune()

void fm_end_tune

(

fm_t *

ctx

)

End tunning.

Parameters

ctx	Click object.

@description This function ends tunning radio station by setting TUNE bit LOW This function must be executed after getting tune done interrupt flag This function can be executed before getting tune done interrupt flag

fm_fine_tune_down()

uint8_t fm_fine_tune_down

(

fm_t *

ctx

)

Fine tunning.

Parameters

ctx	Click object.

Returns

0 if tuned frequency is in valid range; 1 if tuned frequency reached lower band limit @description This fine tunes frequency in smallest possible increments for spacing setting

fm_fine_tune_up()

uint8_t fm_fine_tune_up

(

fm_t *

ctx

)

Fine tunning.

Parameters

ctx	Click object.

Returns

0 if tuned frequency is in valid range; 1 if tuned frequency reached upper band limit

@description This fine tunes frequency in smallest possible increments for spacing setting

fm_generic_read()

void fm_generic_read	(	fm_t *	ctx,
		uint16_t *	reg_buf )

Reading all registers.

Parameters

ctx	Click object.
reg_buf	All registers to be read are stored into reg_buf[ 16 ].

@description This function reads all registers in device starting from address 0x0A This function sorts all device registers in such manner that reg_buf[] can be used with fm_generic_write(); without change

fm_generic_write()

void fm_generic_write	(	fm_t *	ctx,
		uint16_t *	reg_buf )

Generic write function.

Parameters

ctx	Click object.
reg_buf	All registers to be written are stored into reg_buf[ 16 ].

@description This function writes all registers from device starting from address 0x02 This function should be used after fm_generic_read(); and fm_set_bits(); functions

fm_get_an_pin()

uint8_t fm_get_an_pin

(

fm_t *

ctx

)

Checking AN pin status.

Returns

int pin status - (0 or 1)

@description This function returns 0 if AN pin is LOW or 1 if AN pin is HIGH

fm_get_channel()

uint16_t fm_get_channel

(

fm_t *

ctx

)

Reading CHANNEL bits.

Parameters

ctx	Click object.

Returns

channel - value of channel bits - bits [9:0]

@description This function reads CHANNEL bits from READCHAN register

fm_get_channel_frequency()

float fm_get_channel_frequency

(

fm_t *

ctx

)

Calculating current channel frequency.

Parameters

ctx	Click object.

Returns

channel_frequency - current channel frequency in MHz

@description This function calculates current channel frequency based on band and space settings

fm_get_errors_block_a()

uint8_t fm_get_errors_block_a

(

fm_t *

ctx

)

Reading number of errors to be corrected.

Parameters

ctx	Click object.

Returns

n_errors - value that represents number of errors to be corrected

@description This function returns BLERA error bits from status RSSI register This function returns 00h if 0 errors occured This function returns 01h if 1–2 errors occured This function returns 10h if 3–5 errors occured This function returns 11h if 6+ errors occured and correction is not possible.

fm_get_errors_block_b()

uint8_t fm_get_errors_block_b

(

fm_t *

ctx

)

Reading number of errors to be corrected.

Parameters

ctx	Click object.

Returns

n_errors - value that represents number of errors to be corrected

@description This function returns BLERB error bits from read Channel register This function returns 00h if 0 errors occured This function returns 01h if 1–2 errors occured This function returns 10h if 3–5 errors occured This function returns 11h if 6+ errors occured and correction is not possible.

fm_get_errors_block_c()

uint8_t fm_get_errors_block_c

(

fm_t *

ctx

)

Reading number of errors to be corrected.

Parameters

ctx	Click object.

Returns

n_errors - value that represents number of errors to be corrected

@description This function returns BLERC error bits from read Channel register This function returns 00h if 0 errors occured This function returns 01h if 1–2 errors occured This function returns 10h if 3–5 errors occured This function returns 11h if 6+ errors occured and correction is not possible.

fm_get_errors_block_d()

uint8_t fm_get_errors_block_d

(

fm_t *

ctx

)

Reading number of errors to be corrected.

Parameters

ctx	Click object.

Returns

n_errors - value that represents number of errors to be corrected

@description This function returns BLERD error bits from read Channel register This function returns 00h if 0 errors occured This function returns 01h if 1–2 errors occured This function returns 10h if 3–5 errors occured This function returns 11h if 6+ errors occured and correction is not possible.

fm_get_int_pin()

uint8_t fm_get_int_pin

(

fm_t *

ctx

)

Checking INT pin status.

Parameters

ctx	Click object.

Returns

int pin status - (0 or 1)

@description This function returns 0 if INT pin is LOW or 1 if INT pin is HIGH

fm_get_received_signal_strength_indicator()

uint8_t fm_get_received_signal_strength_indicator

(

fm_t *

ctx

)

Reading recived strength indicator.

Parameters

ctx	Click object.

Returns

rssi_value - value of recived signal strength in dBuV

@description This function reads recived signal strength indicatior

fm_init()

FM_RETVAL fm_init	(	fm_t *	ctx,
		fm_cfg_t *	cfg )

Initialization function.

Parameters

ctx	Click object.
cfg	Click configuration structure.

@description This function initializes all necessary pins and peripherals used for this click.

fm_mute_disable()

void fm_mute_disable

(

fm_t *

ctx

)

Disable mute.

Parameters

ctx	Click object.

@description This function disables mute

fm_mute_enable()

void fm_mute_enable

(

fm_t *

ctx

)

Enable mute.

Parameters

ctx	Click object.

@description This function enables mute

fm_power_down()

void fm_power_down

(

fm_t *

ctx

)

Powering down device.

Parameters

ctx	Click object.

@description This function powers down device

fm_power_up()

void fm_power_up

(

fm_t *

ctx

)

Powering up device.

Parameters

ctx	Click object.

@description This function powers up device This function first selects 2 wire mode for I2C This function than enables crystal oscylator and waits for it to settle This function than sets ENABLE bit HIGH and DISABLE bit LOW and waits for device to powerup

fm_seek()

void fm_seek

(

fm_t *

ctx

)

Start seeking radio station.

Parameters

ctx	Click object.

@description This function starts seeking radio stations according to basic seek setings This function seeks stations by seeking up and wraps to lower band limit upon reaching upper band limit if basic settings have not been changed

fm_set_bits()

void fm_set_bits	(	uint16_t *	register_buffer,
		uint16_t	register_address,
		uint16_t	bits_mask,
		uint16_t	bits_value )

Setting bits in specific register on a specific bit location.

Parameters

ctx	Click object.
register_buffer	All device registers are read into register_buffer[ 16 ].
register_address	Address of the register whose bits are to be set.
bits_mask	Bits to be set must be masked first.
bits_value	Value of the bits in selected range.

@description This function is used to set bits in specific register on a specific position This function is used after fm_generic_read( uint16_t *register_buffer ) This function is used before fm_generic_write( uint16_t *register_buffer )

fm_set_seek_impulse_detection_threshold()

uint8_t fm_set_seek_impulse_detection_threshold	(	fm_t *	ctx,
		uint8_t	impulse_detection_threshold )

Setting seek impulse detection threshold value.

Parameters

ctx	Click object.

Returns

0 or 1

@description This function sets impulse detection threshold value This function sets SKCNT bits in System configuration 3 register This function returns 0 if threshold value is in valid range This function returns 1 if threshold value is not in valid range

fm_set_seek_threshold()

uint8_t fm_set_seek_threshold	(	fm_t *	ctx,
		uint16_t	seek_threshold )

Setting seek threshold value.

Parameters

ctx	Click object.
seek_threshold	Value of seek threshold.

Returns

0 or 1

@description This function sets seek threshold value This function returns 0 if threshold value is in valid range This function returns 1 if threshold value is not in valid range

fm_set_snr_threshold()

uint8_t fm_set_snr_threshold	(	fm_t *	ctx,
		uint8_t	snr_threshold )

Setting seek SNR threshold value.

Parameters

ctx	Click object.

Returns

0 or 1

@description This function sets seek SNR threshold value This function sets SKSNR bits in System configuration 3 register This function returns 0 if threshold value is in valid range This function returns 1 if threshold value is not in valid range

fm_set_volume()

uint8_t fm_set_volume	(	fm_t *	ctx,
		uint8_t	volume_level )

Setting volume value.

Parameters

ctx	Click object.
volume_level	Desired volume value

Returns

0 or 1

@description This function sets volume value (0-16) This function sets VOLUME bits [3:0] in System configuration 2 register This function returns 0 if volume value is in range This function returns 1 if volume value is not in range

fm_tune()

uint8_t fm_tune	(	fm_t *	ctx,
		float	channel_frequency )

Tunning radio station.

Parameters

ctx	Click object.
channel_frequency	- frequency of the channel to be tuned

Returns

0 or 1

@description This function sets channel for desired radio station and sets tune enable bit This function returns 0 if radio station frequency is in valid range This function returns 1 if radio station frequency is not in valid range

fm_tune_channel()

void fm_tune_channel	(	fm_t *	ctx,
		uint16_t	channel )

Setting CHANNEL bits.

Parameters

ctx	Click object.
channel	- value stored in channel bits - bits [9:0]

@description This function sets CHANNEL bits in CHANNEL register

fm_volume_down()

uint8_t fm_volume_down

(

fm_t *

ctx

)

Decreasing volume level.

Parameters

ctx	Click object.

Returns

(o or 1)

@description This function decreases volume level This function returns 0 if volume level decreased This function returns 1 if volume level reached minimum value

fm_volume_up()

uint8_t fm_volume_up

(

fm_t *

ctx

)

Increasing volume level.

Parameters

ctx	Click object.

Returns

(o or 1)

@description This function increases volume level This function returns 0 if volume level increased This function returns 1 if volume level reached maximum value