Library Description

The library covers all the necessary functions that enables the usage of the Heart rate 4 Click board. It initializes and defines the I2C bus driver and drivers that offer a choice for writing and reading and setting a new value. Also, user can set, clear or check many different interrupts, as well as read from FIFO register.

Key functions:

• void heartrate4_setDefaultSettings() - Function is used to apply default settings.
• uint8_t heartrate4_getInt1() - Function is used to read the main interrupt group.
• uint32_t heartrate4_getRedVal() - Function is used to read the RED value.

Examples description

The application is composed of three sections :

• System Initialization - Initializes I2C module, LOG and GPIO structures, sets INT pin as input.
• Application Initialization - Initalizes I2C driver, applies default settings, and makes an initial log.
• Application Task - This example demonstrates the use of Heart rate 4 board. It is set in heart rate mode, and reads reflected red values and displays the results on USART terminal.

void applicationTask()
{
    if( heartrate4_getInt1() & 0x40 )
    {
        redSamp = heartrate4_getRedVal();
        if( redSamp > 0 && redSamp < 32000 )
        {
            mikrobus_logWrite( "Place Finger On Sensor", _LOG_LINE );
        }
        else if( redSamp != 0 )
        {
            LongWordToStr( redSamp, logTxt );
            Ltrim( logTxt );
            mikrobus_logWrite( "Heart rate : ", _LOG_TEXT );
            mikrobus_logWrite( logTxt, _LOG_LINE );
        }
        mikrobus_logWrite( "------------------------------", _LOG_LINE );
        Delay_ms( 1000 );
    }
    else
    {
        Delay_ms( 1 );
    }
}

Other mikroE Libraries used in the example:

• I2C
• UART
• Conversions

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.