Spectrometer Click

Spectrometer Click features an 11-channel spectrometer for spectral identification and color matching applications. This Click board™ features the AS7341 from AMS-AG, whose spectral response is defined in the wavelengths from approximately 350nm to 1000nm.

Click Product page

Click library

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

Software Support

We provide a library for the Spectrometer 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 Spectrometer Click driver.

Standard key functions :

• Config Object Initialization function.

  void spectrometer_cfg_setup ( spectrometer_cfg_t *cfg );

• Initialization function.

  SPECTROMETER_RETVAL spectrometer_init ( spectrometer_t ctx, spectrometer_cfg_t cfg );

• Default configuration function

  void spectrometer_def_cfg ( spectrometer_t *ctx );

Example key functions :

• This function is used to read out channels with SMUX configration 1; F1-F4, Clear.

  void spectrometer_raw_rd_val_mode_1 ( spectrometer_t ctx, uint8_t adc_data );

• This function is used to read out channels with SMUX configration 2; F5-F8, Clear.

  void spectrometer_raw_rd_val_mode_2 ( spectrometer_t ctx, uint8_t adc_data );

• This function is used to detect flicker for 100 and 120 Hz.

  uint8_t spectrometer_flicker_detection ( spectrometer_t *ctx );

Examples Description

This Click is an 11-channel spectrometer for spectral identification and color matching. The spectral response is defined in the wavelengths from approximately 350nm to 1000nm. 8 optical channels cover the visible spectrum, one channel can be used to measure near infra-red light and one channel is a photo diode without filter (“clear”). The device also integrates a dedicated channel to detect 50Hz or 60Hz ambient light flicker.

The demo application is composed of two sections :

Application Init

Initalizes I2C driver, performs safety check and makes an initial log.

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

    /** 
     * 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.

    spectrometer_cfg_setup( &cfg );
    SPECTROMETER_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    spectrometer_init( &spectrometer, &cfg );
    Delay_ms ( 100 );

    spectrometer_generic_read ( &spectrometer, SPECTROMETER_ID, &id_val, 1 );
    if ( id_val == SPECTROMETER_ID_VALUE )
    {
        log_printf( &logger, "-------------------------\r\n" );
        log_printf( &logger, "   Spectrometer  Click   \r\n" );
        log_printf( &logger, "-------------------------\r\n" );
    }
    else
    {
        log_printf( &logger, "-------------------------\r\n" );
        log_printf( &logger, "     FATAL  ERROR!!!     \r\n" );
        log_printf( &logger, "-------------------------\r\n" );
        for ( ; ; );
    }
    Delay_ms ( 100 );

    spectrometer_def_cfg( &spectrometer );
    Delay_ms ( 100 );
}

Application Task

This example shows the capabilities of the Spectrometer Click by reading out channels with SMUX configrations 1 and 2, detecting flicker for 100 and 120 Hz and displaying data via USART terminal.

void application_task ( void )
{
    spectrometer_raw_rd_val_mode_1( &spectrometer, &adc_buf[ 0 ] );

    ch_0 = adc_buf[ 1 ];
    ch_0 <<= 8;
    ch_0 |= adc_buf[ 0 ];
    log_printf( &logger, " ADC0/F1 : %u\r\n", ch_0 );

    ch_1 = adc_buf[ 3 ];
    ch_1 <<= 8;
    ch_1 |= adc_buf[ 2 ];
    log_printf( &logger, " ADC1/F2 : %u\r\n", ch_1 );

    ch_2 = adc_buf[ 5 ];
    ch_2 <<= 8;
    ch_2 |= adc_buf[ 4 ];
    log_printf( &logger, " ADC2/F3 : %u\r\n", ch_2 );

    ch_3 = adc_buf[ 7 ];
    ch_3 <<= 8;
    ch_3 |= adc_buf[ 6 ];
    log_printf( &logger, " ADC3/F4 : %u\r\n", ch_3 );

    ch_4 = adc_buf[ 9 ];
    ch_4 <<= 8;
    ch_4 |= adc_buf[ 8 ];
    log_printf( &logger, " ADC4/Clear : %u\r\n", ch_4 );

    spectrometer_raw_rd_val_mode_2( &spectrometer, &adc_buf[ 0 ] );

    ch_0 = adc_buf[ 1 ];
    ch_0 <<= 8;
    ch_0 |= adc_buf[ 0 ];
    log_printf( &logger, " ADC0/F5 : %u\r\n", ch_0 );

    ch_1 = adc_buf[ 3 ];
    ch_1 <<= 8;
    ch_1 |= adc_buf[ 2 ];
    log_printf( &logger, " ADC1/F6 : %u\r\n", ch_1 );

    ch_2 = adc_buf[ 5 ];
    ch_2 <<= 8;
    ch_2 |= adc_buf[ 4 ];
    log_printf( &logger, " ADC2/F7 : %u\r\n", ch_2 );

    ch_3 = adc_buf[ 7 ];
    ch_3 <<= 8;
    ch_3 |= adc_buf[ 6 ];
    log_printf( &logger, " ADC3/F8 : %u\r\n", ch_3 );

    ch_4 = adc_buf[ 9 ];
    ch_4 <<= 8;
    ch_4 |= adc_buf[ 8 ];
    log_printf( &logger, " ADC4/Clear : %u\r\n", ch_4 );

    f_val = spectrometer_flicker_detection( &spectrometer );

    log_printf( &logger, " Flicker : " );
    if ( f_val == SPECTROMETER_UNKNOWN_FREQ )
    {
        log_printf( &logger, "unknown\r\n" );
    }
    else if ( f_val == SPECTROMETER_DETECTED_100_HZ )
    {
        log_printf( &logger, "100 Hz detected\r\n" );
    }
    else if ( f_val == SPECTROMETER_DETECTED_120_HZ )
    {
        log_printf( &logger, "120 Hz detected\r\n" );
    }
    else
    {
        log_printf( &logger, "Error in reading\r\n" );
    }

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

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.Spectrometer

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.