IR Grid 4 Click

IR Grid 4 Click is a compact add-on board for high-precision, non-contact temperature measurement and thermal imaging. This board is based on the MLX90641, a fully calibrated thermal IR array from Melexis. It captures temperature data across a 16x12 matrix (192 pixels) and accurately measures temperatures from -40°C to +300°C with a typical accuracy of 1°C. The board supports the innovative 'Click Snap' feature, allowing the sensor area to be detached for flexible positioning.

Click Product page

Click library

• Author : Stefan Filipovic
• Date : Jul 2024.
• Type : I2C type

Software Support

We provide a library for the IR Grid 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 IR Grid 4 Click driver.

Standard key functions :

• irgrid4_cfg_setup Config Object Initialization function.

  void irgrid4_cfg_setup ( irgrid4_cfg_t *cfg );

• irgrid4_init Initialization function.

  err_t irgrid4_init ( irgrid4_t *ctx, irgrid4_cfg_t *cfg );

• irgrid4_default_cfg Click Default Configuration function.

  err_t irgrid4_default_cfg ( irgrid4_t *ctx );

Example key functions :

• irgrid4_get_measurement This function reads the RAM frame data and calculates ambient temperature and a 16x12 IR grid object temperature.

  err_t irgrid4_get_measurement ( irgrid4_t *ctx, float *t_amb, float *t_obj );

• irgrid4_set_refresh_rate This function sets the IR data refresh rate.

  err_t irgrid4_set_refresh_rate ( irgrid4_t *ctx, uint8_t refresh_rate );

• irgrid4_enable_led1 This function enables the LED1.

  void irgrid4_enable_led1 ( irgrid4_t *ctx );

Example Description

This example demonstrates the use of IR Grid 4 Click by reading and displaying the ambient and object temperature measurements in a 16x12 pixels grid format.

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. */
    irgrid4_cfg_t irgrid4_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.
    irgrid4_cfg_setup( &irgrid4_cfg );
    IRGRID4_MAP_MIKROBUS( irgrid4_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == irgrid4_init( &irgrid4, &irgrid4_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( IRGRID4_ERROR == irgrid4_default_cfg ( &irgrid4 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }

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

Application Task

Reads the ambient and object temperature measurements every 500ms and displays the results on the USB UART in a form of a 16x12 pixels grid.

void application_task ( void )
{
    float image[ 192 ] = { 0 };
    float ambient_temp = 0;
    if ( IRGRID4_OK == irgrid4_get_measurement ( &irgrid4, &ambient_temp, image ) )
    {
        log_printf( &logger, " Ambient temperature: %.2f degC\r\n", ambient_temp );
        log_printf( &logger, "--- Object temperature image ---\r\n" );
        for ( uint8_t pixel_cnt = 0; pixel_cnt < 192; pixel_cnt++ ) 
        {
            log_printf( &logger, "%.2f", image[ pixel_cnt ] );
            if ( 15 == ( pixel_cnt % 16 ) ) 
            {
                log_printf( &logger, "\r\n" );
            }
            else 
            {
                log_printf( &logger, " | " );
            }
        }
        log_printf( &logger, "--------------------------------\r\n" );
    }
}

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.IRGrid4

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.