TempHum 22 Click

Temp&Hum 22 Click is a compact add-on board representing temperature and humidity sensing solution. This board features the SHT41A, a 4th generation automotive-grade relative humidity and temperature sensor from Sensirion. The SHT41A is characterized by its high accuracy (±2% RH and ±0.3°C over a wide operating temperature range) and high resolution providing 16-bit data to the host controller with a configurable I2C interface. Also, it is designed for reliable operation in harsh conditions such as condensing environments.

Click Product page

Click library

• Author : Stefan Filipovic
• Date : Aug 2022.
• Type : I2C type

Software Support

We provide a library for the TempHum 22 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 TempHum 22 Click driver.

Standard key functions :

• temphum22_cfg_setup Config Object Initialization function.

  void temphum22_cfg_setup ( temphum22_cfg_t *cfg );

• temphum22_init Initialization function.

  err_t temphum22_init ( temphum22_t *ctx, temphum22_cfg_t *cfg );

Example key functions :

• temphum22_soft_reset This function performs the software reset by sending the soft reset command.

  err_t temphum22_soft_reset ( temphum22_t *ctx );

• temphum22_read_serial_num This function reads the 4-bytes unique serial number by using I2C serial interface.

  err_t temphum22_read_serial_num ( temphum22_t *ctx, uint32_t *serial_num );

• temphum22_read_measurement_high_precision This function reads the temperature and humidity measurements with high precision.

  err_t temphum22_read_measurement_high_precision ( temphum22_t *ctx, float *temp, float *hum );

Example Description

This example demonstrates the use of Temp & Hum 22 Click board by reading the temperature and humidity data.

The demo application is composed of two sections :

Application Init

Initializes the driver, performs the sensor software reset and then reads and displays the sensor unique serial number.

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    temphum22_cfg_t temphum22_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.
    temphum22_cfg_setup( &temphum22_cfg );
    TEMPHUM22_MAP_MIKROBUS( temphum22_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == temphum22_init( &temphum22, &temphum22_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( TEMPHUM22_OK == temphum22_soft_reset ( &temphum22 ) )
    {
        log_printf ( &logger, " Software reset\r\n" );
    }
    Delay_1sec ( );

    uint32_t serial_num;
    if ( TEMPHUM22_OK == temphum22_read_serial_num ( &temphum22, &serial_num ) )
    {
        log_printf ( &logger, " Serial number: 0x%.8LX\r\n", serial_num );
    }

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

Application Task

Reads the temperature (degC) and the relative humidity (%RH) data and displays the results on the USB UART approximately once per second.

void application_task ( void )
{
    float temperature, humidity;
    if ( TEMPHUM22_OK == temphum22_read_measurement_high_precision ( &temphum22, &temperature, &humidity ) )
    {
        log_printf ( &logger, " Temperature: %.2f degC\r\n", temperature );
        log_printf ( &logger, " Humidity: %.2f %%RH\r\n\n", humidity );
        Delay_ms ( 1000 );
    }
}

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.TempHum22

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.