RTD Click

RTD Click is based on MAX31865 resistance to digital converter from Maxim Integrated, optimized for platinum resistance temperature detectors, or RTD.

Click Product page

Click library

• Author : MikroE Team
• Date : Feb 2020.
• Type : SPI type

Software Support

We provide a library for the Rtd 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 Rtd Click driver.

Standard key functions :

• rtd_cfg_setup Config Object Initialization function.

  void rtd_cfg_setup ( rtd_cfg_t *cfg ); 

• rtd_init Initialization function.

  err_t rtd_init ( rtd_t *ctx, rtd_cfg_t *cfg );

Example key functions :

• rtd_read_register This function reads data from the chosen register.

  uint8_t rtd_read_register ( rtd_t *ctx, uint8_t reg_address );

• rtd_read_temperature This function reads data from temperature registers.

  uint16_t rtd_read_temperature ( rtd_t *ctx );

• rtd_convert_temperature This function convert data from temperature registers.

  float rtd_convert_temperature ( rtd_t *ctx, uint16_t input_data, uint16_t referent_resistance );

Examples Description

This app measures temperature and converts the data to celsius degrees.

The demo application is composed of two sections :

Application Init

Initializes RTD Click driver, and sets the proper configuration mode for three wire RTD.

void application_init ( void )
{
    log_cfg_t log_cfg;
    rtd_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.
    rtd_cfg_setup( &cfg );
    RTD_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    rtd_init( &rtd, &cfg );

    RTD_SET_DATA_SAMPLE_EDGE;

    rtd_write_register( &rtd, RTD_CONFIGURATION, 0xD0 );
    Delay_ms ( 100 );
    log_info( &logger, " Application Task " );
}

Application Task

Measures temperature, converts the data to celsius degrees, and displays it on the USB UART.

void application_task ( void )
{
    uint16_t read_value = 0;
    float converted_value = 0;

    read_value = rtd_read_temperature( &rtd );
    converted_value = rtd_convert_temperature( &rtd, read_value, RTD_REF_RESISTANCE_470 );

    log_printf( &logger, " Current temperature: %.2f \r\n", converted_value );

    Delay_ms ( 300 );
}

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.Rtd

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.