Library Description

The library covers all the necessary functions to control the HVAC Click board.
A library performs the communication with the SCD40 Sensor via the I2C interface
and with the SPS30 via the I2C or UART interface.

Key functions:

• void hvac_scd40_read_measurement ( measuremen_data_t *m_data ) - SCD40 read measurement function.
• void hvac_sps30_start_measurement ( void ) -
  SPS30 starts the measurement command function.
• void hvac_sps30_read_measured_data ( mass_and_num_cnt_data_t *m_n_c_data ) -
  TSPS30 read measured data function.

Examples description

The application is composed of three sections :

• System Initialization - Initializes I2C or UART and start to write log.
• Application Initialization - Initialization driver enables - I2C or UART,
   SCD40: perform factory reset, serial number, features, product type
   platform type, product version and
   SPS30: perform start measurement mode, also write log.
• Application Task - (code snippet) This is an example which demonstrates the use of HVAC Click board.
   HVAC Click board can be used to measure :
   Concentration of CO2 in air,
   Temperature ( degree Celsius ),
   Relative Humidity ( % ),
   Mass Concentration of PM1.0, PM2.5, PM4.0, PM10 and
   Number Concentration of PM0.5, PM1.0, PM2.5, PM4.0 and PM10.
   All data logs write on USB uart changes.

void application_task ( )
{
    if ( select_communication == I2C_COMMUNICATION )
    {
        hvac_scd40_send_cmd( HVAC_MEASURE_SINGLE_SHOT );
        Delay_ms( 5000 );

        hvac_scd40_read_measurement( &hvac_data );
        Delay_ms( 100 );

        WordToStr( hvac_data.co2_concent, log_text );
        mikrobus_logWrite( " CO2 Concent = ", _LOG_TEXT );
        mikrobus_logWrite( log_text, _LOG_LINE );

        FloatToStr( hvac_data.temperature, log_text );
        mikrobus_logWrite( " Temperature = ", _LOG_TEXT );
        mikrobus_logWrite( log_text, _LOG_TEXT );
        mikrobus_logWrite( " C", _LOG_LINE );

        FloatToStr( hvac_data.r_humidity, log_text );
        mikrobus_logWrite( " R. Humidity = ", _LOG_TEXT );
        mikrobus_logWrite( log_text, _LOG_TEXT );
        mikrobus_logWrite( " %", _LOG_LINE );
        mikrobus_logWrite( "- - - - - - - - - - - - - ", _LOG_LINE );

        while ( hvac_sps30_get_ready_flag( ) != HVAC_SPS30_NEW_DATA_IS_READY );
    }
    mikrobus_logWrite( "   Mass Concentration :   ", _LOG_LINE );
    hvac_sps30_read_measured_data( &sps30_data );
    Delay_ms( 100 );

    FloatToStr( sps30_data.mass_pm_1_0, log_text );
    mikrobus_logWrite( " PM 1.0 = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " ug/m3", _LOG_LINE );

    FloatToStr( sps30_data.mass_pm_2_5, log_text );
    mikrobus_logWrite( " PM 2.5 = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " ug/m3", _LOG_LINE );

    FloatToStr( sps30_data.mass_pm_4_0, log_text );
    mikrobus_logWrite( " PM 4.0 = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " ug/m3", _LOG_LINE );

    FloatToStr( sps30_data.mass_pm_10, log_text );
    mikrobus_logWrite( " PM 10  = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " ug/m3", _LOG_LINE );
    mikrobus_logWrite( "-   -   -   -   -   -   - ", _LOG_LINE );

    mikrobus_logWrite( "  Number Concentration :  ", _LOG_LINE );
    FloatToStr( sps30_data.num_pm_0_5, log_text );
    mikrobus_logWrite( " PM 0.5 = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " n/cm3", _LOG_LINE );

    FloatToStr( sps30_data.num_pm_1_0, log_text );
    mikrobus_logWrite( " PM 1.0 = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " n/cm3", _LOG_LINE );

    FloatToStr( sps30_data.num_pm_2_5, log_text );
    mikrobus_logWrite( " PM 2.5 = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " n/cm3", _LOG_LINE );

    FloatToStr( sps30_data.num_pm_4_0, log_text );
    mikrobus_logWrite( " PM 4.0 = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " n/cm3", _LOG_LINE );

    FloatToStr( sps30_data.num_pm_10, log_text );
    mikrobus_logWrite( " PM 10  = ", _LOG_TEXT );
    mikrobus_logWrite( log_text, _LOG_TEXT );
    mikrobus_logWrite( " n/cm3", _LOG_LINE );
    mikrobus_logWrite( "--------------------------", _LOG_LINE );
    Delay_ms( 2000 );
}
}

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.