Ambient 18 Click

Ambient 18 Click is a compact add-on board used to sense the amount of the present ambient light. This board features the BH1680FVC, an analog current-output ambient light sensor from Rohm Semiconductor. The BH1680FVC can detect a wide range of illuminance up to 10klx and provides excellent responsivity close to the human eyes' response. Besides, it is also characterized by low sensitivity variation across various light sources, a built-in shutdown function, and the ability to process the output signal in analog or digital form. This Click board™ is the most suitable for obtaining ambient light data for adjusting brightness in applications that require power saving and better visibility.

Click Product page

Click library

• Author : Stefan Filipovic
• Date : Dec 2021.
• Type : ADC/I2C type

Software Support

We provide a library for the Ambient 18 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 from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for Ambient 18 Click driver.

Standard key functions :

• ambient18_cfg_setup Config Object Initialization function.

  void ambient18_cfg_setup ( ambient18_cfg_t *cfg );

• ambient18_init Initialization function.

  err_t ambient18_init ( ambient18_t *ctx, ambient18_cfg_t *cfg );

Example key functions :

• ambient18_set_gain_mode This function sets the gain mode.

  void ambient18_set_gain_mode ( ambient18_t *ctx, uint8_t mode );

• ambient18_read_voltage This function reads raw ADC value and converts it to proportional voltage level.

  err_t ambient18_read_voltage ( ambient18_t *ctx, float *voltage );

• ambient18_voltage_to_lux This function calculates illuminance (lux) based on the voltage input.

  int32_t ambient18_voltage_to_lux ( ambient18_t *ctx, float voltage );

Example Description

This example demonstrates the use of Ambient 18 Click board by measuring and displaying the illuminance value in Lux.

The demo application is composed of two sections :

Application Init

Initializes the driver and sets the gain mode to M-Gain which can detect the illuminance of up to 1000 lux.

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    ambient18_cfg_t ambient18_cfg;  /**< Click config object. */

    /** 
     * 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.
    ambient18_cfg_setup( &ambient18_cfg );
    AMBIENT18_MAP_MIKROBUS( ambient18_cfg, MIKROBUS_1 );
    err_t init_flag = ambient18_init( &ambient18, &ambient18_cfg );
    if ( ( ADC_ERROR == init_flag ) || ( I2C_MASTER_ERROR == init_flag ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    ambient18_set_gain_mode ( &ambient18, AMBIENT18_MODE_M_GAIN );
    log_printf( &logger, " M-Gain mode selected.\r\n Up to 1000 lux can be measured.\r\n" );

    log_info( &logger, " Application Task " );
}

Application Task

Reads the ADC voltage and then calculates the illuminance from it. The calculated value of illuminance in lux is being displayed on the USB UART approximately once per second.

void application_task ( void )
{
    float voltage = 0;
    if ( AMBIENT18_OK == ambient18_read_voltage ( &ambient18, &voltage ) ) 
    {
        log_printf( &logger, " Illuminance : %ld Lux\r\n\n", ambient18_voltage_to_lux( &ambient18, voltage ) );
        Delay_ms ( 1000 );
    }
}

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.Ambient18

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. UART terminal is available in all MikroElektronika compilers.