fm  2.0.0.0
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FM click

FM Click with it’s Si4703 IC is a complete FM radio tuner in the form of add-on board. It supports worldwide FM band (76 – 108 MHz).

click Product page


Click library

  • Author : MikroE Team
  • Date : Jan 2020.
  • Type : I2C type

Software Support

We provide a library for the Fm Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly form compilers IDE(recommended way), or downloaded from our LibStock, or found on mikroE github account.

Library Description

This library contains API for Fm Click driver.

Standard key functions :

  • Config Object Initialization function.

    void fm_cfg_setup ( fm_cfg_t *cfg );

  • Initialization function.

    FM_RETVAL fm_init ( fm_t *ctx, fm_cfg_t *cfg );

  • Click Default Configuration function.

    void fm_default_cfg ( fm_t *ctx );

Example key functions :

  • This function reads recived signal strength indicatior

    uint8_t fm_get_received_signal_strength_indicator ( fm_t *ctx );

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

    float fm_get_channel_frequency ( fm_t *ctx );

  • This function reads CHANNEL bits from READCHAN register

    uint16_t fm_get_channel ( fm_t *ctx );

Examples Description

This click represent FM radio tuner which supports worldwide FM band (76 – 108 MHz) and has a set of features such as automatic frequency and gain control, seek tuning and volume control.

The demo application is composed of two sections :

Application Init

Initializing I2C driver, powering up device, setting basic settings for Europe, setting values of seek threshold, volume, snr threshold and impulse detection threshold. Seek and memorize 5 radio stations with a signal strength above the set limit.

void application_init ( void )
{
log_cfg_t log_cfg;
fm_cfg_t cfg;
LOG_MAP_USB_UART( log_cfg );
log_init( &logger, &log_cfg );
log_info( &logger, "---- Application Init ----" );
// Click initialization.
fm_cfg_setup( &cfg );
FM_MAP_MIKROBUS( cfg, MIKROBUS_1 );
fm_init( &fm, &cfg );
Delay_ms ( 500 );
memory = 0;
mute = 0;
fm_case_mute( &fm );
for ( cnt = 0; cnt < 5; )
{
log_printf( &logger, "seeking...\r\n" );
do
{
received_signal_strength_indicator = 0;
fm_case_seek( &fm );
}
while ( received_signal_strength_indicator < SIGNAL_STRENGTH_LOWER_LIMIT ); //rssi value
log_printf( &logger, "station found\r\n" );
log_printf( &logger, "rssi: %u dBuV\r\n", received_signal_strength_indicator );
log_printf( &logger, "channel frequency: %.2f MHz\r\n", channel_frequency );
log_printf( &logger, "-----------------------\r\n" );
Delay_ms ( 100 );
cnt++;
}
mute = 1;
fm_case_mute( &fm );
log_printf( &logger, "playing memorized stations...\r\n\r\n" );
}

Application Task

Tunes all memorized stations. Switches the stations each 10 seconds.

void application_task ( void )
{
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );
}

The full application code, and ready to use projects can be installed directly form compilers IDE(recommneded) or found on LibStock page or mikroE GitHub accaunt.

Other mikroE Libraries used in the example:

  • MikroSDK.Board
  • MikroSDK.Log
  • Click.Fm

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. The terminal available in all Mikroelektronika compilers, or any other terminal application of your choice, can be used to read the message.


FM_MAP_MIKROBUS
#define FM_MAP_MIKROBUS(cfg, mikrobus)
Definition: fm.h:66
fm_case_seek
void fm_case_seek(fm_t *ctx)
Definition: main.c:99
fm_cfg_t
Click configuration structure definition.
Definition: fm.h:311
fm_init
FM_RETVAL fm_init(fm_t *ctx, fm_cfg_t *cfg)
Initialization function.
fm_cfg_setup
void fm_cfg_setup(fm_cfg_t *cfg)
Config Object Initialization function.
application_task
void application_task(void)
Definition: main.c:444
fm_case_station_1
void fm_case_station_1(fm_t *ctx)
Definition: main.c:219
fm_case_station_4
void fm_case_station_4(fm_t *ctx)
Definition: main.c:282
fm_case_memorize
void fm_case_memorize()
Definition: main.c:143
fm_case_station_5
void fm_case_station_5(fm_t *ctx)
Definition: main.c:303
SIGNAL_STRENGTH_LOWER_LIMIT
#define SIGNAL_STRENGTH_LOWER_LIMIT
Definition: main.c:45
application_init
void application_init(void)
Definition: main.c:389
fm_default_cfg
void fm_default_cfg(fm_t *ctx)
Click Default Configuration function.
fm_case_station_3
void fm_case_station_3(fm_t *ctx)
Definition: main.c:261
fm_case_mute
void fm_case_mute(fm_t *ctx)
Definition: main.c:199
fm_case_station_2
void fm_case_station_2(fm_t *ctx)
Definition: main.c:240