Air Quality 7 Click

Air quality 7 Click is a compact add-on board that combines state-of-the-art MOS sensor technology with intelligent detection algorithms to monitor VOCs and CO2 equivalent variations in confined spaces.

Click Product page

Click library

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

Software Support

We provide a library for the AirQuality7 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 AirQuality7 Click driver.

Standard key functions :

• Config Object Initialization function.

  void airquality7_cfg_setup ( airquality7_cfg_t *cfg );

• Initialization function.

  AIRQUALITY7_RETVAL airquality7_init ( airquality7_t ctx, airquality7_cfg_t cfg );

Example key functions :

• Get Status function.

  airquality7_err_t airquality7_get_status( airquality7_t ctx, uint16_t tvoc_ppb, uint16_t co2_ppm, uint32_t res_val_ohm, uint8_t *err_byte );

• Get Revision function.

  airquality7_err_t airquality7_get_revision( airquality7_t ctx, uint8_t year, uint8_t month, uint8_t day, uint8_t *ascii_code );

• Get R0 Calibration function.

  airquality7_err_t airquality7_get_r0_calib( airquality7_t ctx, uint16_t r0_kohm );

Examples Description

This demo application measures air quality.

The demo application is composed of two sections :

Application Init

Initializes I2C driver and reads revision date of the module. If CRC check is OK allows the program to go on, otherwise, it displays a message that the program needs to be restarted.

void application_init ( void )
{
    log_cfg_t log_cfg;
    airquality7_cfg_t cfg;

    uint8_t airquality7_rev_year       = AIRQUALITY7_DUMMY;
    uint8_t airquality7_rev_month      = AIRQUALITY7_DUMMY;
    uint8_t airquality7_rev_day        = AIRQUALITY7_DUMMY;
    uint8_t airquality7_rev_ascii_code = AIRQUALITY7_DUMMY;

    /** 
     * 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.

    airquality7_cfg_setup( &cfg );
    AIRQUALITY7_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    airquality7_init( &airquality7, &cfg );


    airquality7_tvoc_ppb    = AIRQUALITY7_DUMMY;
    airquality7_co2_ppm     = AIRQUALITY7_DUMMY;
    airquality7_res_val_ohm = AIRQUALITY7_DUMMY;

    airquality7_err_code = airquality7_get_revision( &airquality7, 
                                                     &airquality7_rev_year,
                                                     &airquality7_rev_month,
                                                     &airquality7_rev_day,
                                                     &airquality7_rev_ascii_code );

    if ( airquality7_err_code == AIRQUALITY7_ERR_OK )
    {
        log_printf( &logger, " Revision date: %.2u.%.2u.%.2u\r\n", ( uint16_t ) airquality7_rev_day, 
                                                                   ( uint16_t ) airquality7_rev_month,
                                                                   ( uint16_t ) airquality7_rev_year );
        log_printf( &logger, " ASCII code for a charter: %u \r\n", ( uint16_t ) airquality7_rev_ascii_code );
    }
    else
    {
        log_printf( &logger, "CRC ERROR READING REVISION. \r\n" );
        Delay_ms ( 1000 );

        for ( ; ; )
        {
            log_printf( &logger, "PLEASE, RESTART YOUR SYSTEM...\r\n" );
            Delay_ms ( 1000 );
            log_printf( &logger, " \r\n \r\n " );
            Delay_ms ( 1000 );
        }
    }

    log_printf( &logger, "----------------------------------------- \r\n" );
    Delay_ms ( 500 );
}

Application Task

Reads air quality status every 1500ms and shows the results on the USB UART.

void application_task ( void )
{
    airquality7_err_code = airquality7_get_status( &airquality7, 
                                                   &airquality7_tvoc_ppb, 
                                                   &airquality7_co2_ppm,
                                                   &airquality7_res_val_ohm, 
                                                   AIRQUALITY7_NULL );

    if ( airquality7_err_code == AIRQUALITY7_ERR_OK )
    {
        uint8_t cnt;

        log_printf( &logger, " tVOC [ppb] = %u \r\n", airquality7_tvoc_ppb );

        log_printf( &logger, " CO2 [ppm] = %u \r\n", airquality7_co2_ppm );

        log_printf( &logger, " Resistor value [ohm] = %lu \r\n", airquality7_res_val_ohm );
        log_printf( &logger, "----------------------------------------- \r\n" );
    }

    Delay_ms ( 1000 );
    Delay_ms ( 500 );
} 

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.AirQuality7

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.