Color 4 Click

Color 4 Click is a compact add-on board providing an accurate color-sensing solution. This board features the VEML6040, a 16-bit RGBW color sensor offering spectral response through a compatible I2C interface from Vishay Semiconductors. The VEML6040 is based on the Filtron™ technology achieving the closest ambient light spectral sensitivity to real-human eye responses. Alongside the color sensor, this IC also incorporates a signal conditioning circuit consisting of photodiodes, amplifiers, and A/D circuits placed into a single chip using the CMOS process. It provides a selectable measurement range up to 16.496lx with the highest sensitivity of 0.007865lx/step.

Click Product page

Click library

• Author : Nenad Filipovic
• Date : Dec 2022.
• Type : I2C type

Software Support

We provide a library for the Color 4 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 Color 4 Click driver.

Standard key functions :

• color4_cfg_setup Config Object Initialization function.

  void color4_cfg_setup ( color4_cfg_t *cfg );

• color4_init Initialization function.

  err_t color4_init ( color4_t *ctx, color4_cfg_t *cfg );

• color4_default_cfg Click Default Configuration function.

  err_t color4_default_cfg ( color4_t *ctx );

Example key functions :

• color4_set_config Color 4 set configuration function.

  err_t color4_set_config ( color4_t *ctx, color4_config_t config ) 

• color4_get_color_data Color 4 get color data function.

  err_t color4_get_color_data ( color4_t *ctx, color4_ch_color_t ch_color, uint16_t *color_data );

• color4_get_ambient_light Color 4 get ambient light level function.

  err_t color4_get_ambient_light ( color4_t *ctx, float *ambient_light );

Example Description

This library contains API for the Color 4 Click driver. This driver provides the functions for the sensor configuration and for reading RGBW and ambient light data from the device. This example displays RGBW data, Ambient light level, CCT data and the light color names.

The demo application is composed of two sections :

Application Init

Initialization of I2C module and log UART. After driver initialization, default settings turn on the device.

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    color4_cfg_t color4_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.
    color4_cfg_setup( &color4_cfg );
    COLOR4_MAP_MIKROBUS( color4_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == color4_init( &color4, &color4_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( COLOR4_ERROR == color4_default_cfg ( &color4 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }

    log_info( &logger, " Application Task " );
    log_printf( &logger, " ----------------------\r\n" );
    Delay_ms ( 100 );
}

Application Task

This example demonstrates the use of the Color 4 Click board™. Reads and displays the results of the RGBW, Ambient light level, calculate the correlated color temperature. This example also detects and displays the light color names. Results are being sent to the UART Terminal, where you can track their changes.

void application_task ( void ) 
{
    if ( COLOR4_OK == color4_get_color_data( &color4, COLOR4_RED, &red_data ) )
    {
        log_printf( &logger, " Red: %u\r\n", red_data );    
    }

    if ( COLOR4_OK == color4_get_color_data( &color4, COLOR4_GREEN, &green_data ) )
    {
        log_printf( &logger, " Green: %u\r\n", green_data );   
    }

    if ( COLOR4_OK == color4_get_color_data( &color4, COLOR4_BLUE, &blue_data ) )
    {
        log_printf( &logger, " Blue: %u\r\n", blue_data );
    }

    if ( COLOR4_OK == color4_get_color_data( &color4, COLOR4_WHITE, &white_data ) )
    {
        log_printf( &logger, " White: %u\r\n", white_data );    
    }
    log_printf( &logger, " - - - - - - -  - - - - \r\n" );

    if ( COLOR4_OK == color4_get_ambient_light( &color4, &ambient_light ) )
    {
        log_printf( &logger, " ALS lux level: %.2f\r\n", ambient_light );    
    }

    if ( COLOR4_OK == color4_get_cct( &color4, &cct ) )
    {
        log_printf( &logger, " CCT: %.2f\r\n", cct );   
    }
    log_printf( &logger, " - - - - - - -  - - - - \r\n" );

    display_color( );
    log_printf( &logger, " ----------------------\r\n" );
    Delay_ms ( 1000 );
}

Note

Color detection is obtained based on the analysis of calculate the correlated color temperature (CCT) data and the CIE 1931 chromaticity diagram. For more details please refer to the “Designing the VEML6040 into an Application” application note (https://www.vishay.com/docs/84331/designingveml6040.pdf).

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.Color4

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.