Light 3 Click

Light 3 Click is a compact add-on board for precise ambient light measurement in automotive applications. This board features the OPT4003-Q1, an automotive-grade digital ambient light sensor from Texas Instruments. This digital ambient light sensor excels in detecting both visible and near-infrared light with high accuracy, thanks to its dual-channel functionality and filters that mimic the human eye's response while efficiently segregating NIR light.

Click Product page

Click library

• Author : Stefan Ilic
• Date : Jan 2024.
• Type : I2C type

Software Support

We provide a library for the Light 3 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 Light 3 Click driver.

Standard key functions :

• light3_cfg_setup Config Object Initialization function.

  void light3_cfg_setup ( light3_cfg_t *cfg );

• light3_init Initialization function.

  err_t light3_init ( light3_t *ctx, light3_cfg_t *cfg );

• light3_default_cfg Click Default Configuration function.

  err_t light3_default_cfg ( light3_t *ctx );

Example key functions :

• light3_sw_reset This function is used to perform software reset.

  err_t light3_sw_reset ( light3_t *ctx );

• light3_write_reg This function writes a desired data into the selected register by using I2C serial interface.

  err_t light3_write_reg ( light3_t *ctx, uint8_t reg, uint16_t data_in );

• light3_get_ch0_data This function reads ambient light data from the Channel 0 and performs the calculatios from raw data to Lux.

  err_t light3_get_ch0_data ( light3_t *ctx, float *lux );

Example Description

This example demonstrates the use of Light 3 Click board by measuring the ambient light level in Lux.

The demo application is composed of two sections :

Application Init

Initializes the driver and performs the Click default configuration.

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    light3_cfg_t light3_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.
    light3_cfg_setup( &light3_cfg );
    LIGHT3_MAP_MIKROBUS( light3_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == light3_init( &light3, &light3_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( LIGHT3_ERROR == light3_default_cfg ( &light3 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }

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

Application Task

Reading channel 0 ambient light level in lux as soon as it is available ( once in 1.6 seconds ) and displaying it on the UART terminal.

void application_task ( void ) 
{
    float lux_data = 0;
    if ( LIGHT3_PIN_STATE_LOW == light3_get_int_pin( &light3 ) )
    { 
        light3_get_ch0_data( &light3, &lux_data );
        log_printf( &logger, "Light level: %f lux \r\n", ( float ) lux_data );
    }
}

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.Light3

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.