heartrate

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Heart Rate Click

Heart Rate Click demo application is developed using the NECTO Studio, ensuring compatibility with mikroSDK's open-source libraries and tools. Designed for plug-and-play implementation and testing, the demo is fully compatible with all development, starter, and mikromedia boards featuring a mikroBUS™ socket.

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Click Library

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

Software Support

Example Description

This Click features an advanced oximeter and heart rate monitoring sensor, which relies on two integrated LEDs. It is enough to place an index finger on a top of the sensor to get both of the heart rate and blood oxygen saturation via the I2C interface.

Example Libraries

• MikroSDK.Board
• MikroSDK.Log
• Click.HeartRate

Example Key Functions

• heartrate_cfg_setup Config Object Initialization function.

void heartrate_cfg_setup ( heartrate_cfg_t *cfg );

• heartrate_init Initialization function.

err_t heartrate_init ( heartrate_t *ctx, heartrate_cfg_t *cfg );

• heartrate_default_cfg Click Default Configuration function.

void heartrate_default_cfg ( heartrate_t *ctx );

• heartrate_data_ready Using this function we can check if the data is ready for reading.

uint8_t heartrate_data_ready ( heartrate_t *ctx );

• heartrate_read_ir_red Using this function we can read IR and RED values.

uint8_t heartrate_read_ir_red ( heartrate_t *ctx, uint16_t *ir_buff, uint16_t *red_buff );

• heartrate_generic_read This function reads data from the desired register.

void heartrate_generic_read ( heartrate_t *ctx, uint8_t reg, uint16_t len, uint8_t *data_buf );

Application Init

Initializes heartrate driver and set the Click board default configuration.

void application_init ( void )
{
    log_cfg_t log_cfg;
    heartrate_cfg_t cfg;

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, "---- Application Init ----" );

    //  Click initialization.

    heartrate_cfg_setup( &cfg );
    HEARTRATE_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    heartrate_init( &heartrate, &cfg );

    heartrate_default_cfg( &heartrate );
    Delay_ms ( 100 );
}

Application Task

Reading values from both Ir and Red diode and displaying their average values on the USB UART.

void application_task ( void )
{
    if ( heartrate_data_ready( &heartrate ) )      
    {
        sample_num = heartrate_read_ir_red( &heartrate, ir_buff, red_buff );             
        if ( sample_num > 0 )
        {
            ir_average = 0;
            red_average = 0;
            for ( uint8_t cnt = 0; cnt < sample_num; cnt++ )
            {              
                ir_average += ir_buff[ cnt ];
                red_average += red_buff[ cnt ];
            }                 
            ir_average  /= sample_num;
            red_average /= sample_num;
            counter++;
            if( red_average > 100 && ir_average > 100 )                
            {       
                log_printf( &logger, "%lu;%lu;\r\n", red_average, ir_average );
                counter = 500;
            }
            else
            {
                if ( counter > 500 ) 
                {
                    log_printf( &logger, "Please place your index finger on the sensor.\r\n" );
                    counter = 0;
                }
            }   
        }
    }
}

Application Output

This Click board can be interfaced and monitored in two ways:

• Application Output - Use the "Application Output" window in Debug mode for real-time data monitoring. Set it up properly by following this tutorial.
• UART Terminal - Monitor data via the UART Terminal using a USB to UART converter. For detailed instructions, check out this tutorial.

Additional Notes and Information

The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.

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