htu21d

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HTU21D Click

HTU21D Click demo application is developed using the NECTO Studio, ensuring compatibility with mikroSDK's open-source libraries and tools. Designed for plug-and-play implementation and testing, the demo is fully compatible with all development, starter, and mikromedia boards featuring a mikroBUS™ socket.

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Click Library

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

Software Support

Example Description

The application is composed of two sections.

Example Libraries

• MikroSDK.Board
• MikroSDK.Log
• Click.Htu21d

Example Key Functions

• htu21d_cfg_setup Config Object Initialization function.

void htu21d_cfg_setup ( htu21d_cfg_t *cfg );

• htu21d_init Initialization function.

err_t htu21d_init ( htu21d_t *ctx, htu21d_cfg_t *cfg );

• htu21d_default_cfg Click Default Configuration function.

void htu21d_default_cfg ( htu21d_t *ctx );

• htu21d_cfg_setup This function initializes Click configuration structure to init state.

void htu21d_cfg_setup ( htu21d_cfg_t *cfg );

• htu21d_init This function initializes all necessary pins and peripherals used for this Click.

err_t htu21d_init ( htu21d_t *ctx, htu21d_cfg_t *cfg );

• htu21d_generic_write This function writes data to the desired register.

void htu21d_generic_write ( htu21d_t *ctx, uint8_t reg, uint8_t *data_buf, uint8_t len );

• htu21d_generic_read This function reads data from the desired register.

void htu21d_generic_read ( htu21d_t *ctx, uint8_t reg, uint8_t *data_buf, uint8_t len );

• htu21d_read_data Function read 24-bit data from register address of HTU21D.

uint32_t htu21d_read_data ( htu21d_t *ctx, uint8_t reg_adr );

• htu21d_send_cmd Function sends command to HTU21D.

void htu21d_send_cmd ( htu21d_t *ctx, uint8_t cmd_byte );

• htu21d_readdata This function reads data from the desired register.

void htu21d_readdata ( htu21d_t *ctx, uint8_t reg, uint8_t *data_buf, uint8_t len );

• htu21d_get_temperature Function read and calculate temperature in degrees Celsius from the HTU21D sensor.

float htu21d_get_temperature ( htu21d_t *ctx );

• htu21d_get_humidity Function read and calculate humidity percentage from the HTU21D sensor.

float htu21d_get_humidity ( htu21d_t *ctx );

Application Init

Initialization driver enable's - I2C, soft reset switch OFF and ON the HTU21D sensor,hold ( required ) after reset 100 [ ms ] and start write log.

void application_init ( void ) { log_cfg_t log_cfg; htu21d_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_printf( &logger, "---- Application Init ----\r\n" );

//  Click initialization.

htu21d_cfg_setup( &cfg );
HTU21D_MAP_MIKROBUS( cfg, MIKROBUS_1 );
htu21d_init( &htu21d, &cfg );

htu21d_send_cmd ( &htu21d, HTU21D_SOFT_RESET );
Delay_ms ( 15 );

log_printf( &logger, "---------------------------\r\n" );
log_printf( &logger, "         HTU21D       \r\n" );
log_printf( &logger, "---------------------------\r\n" );

}

Application Task

This is a example which demonstrates the use of HTU21D Click board.Measured temperature and humidity data from the HDC1000 sensor.Convert temperature data to degrees Celsius and humidity data to percentarg. Results are being sent to the Usart Terminal where you can track their changes. All data logs on usb uart for aproximetly every 3 sec.

void application_task ( void ) { // Task implementation. temperature = htu21d_get_temperature( &htu21d ); log_printf( &logger, " Temperature : %.2f C \r\n", temperature );

humidity = htu21d_get_humidity( &htu21d );
log_printf( &logger, " Humidity : %.2f % \r\n", humidity );

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

Delay_ms ( 1000 );
Delay_ms ( 1000 );
Delay_ms ( 1000 );

}

Application Output

This Click board can be interfaced and monitored in two ways:

• Application Output - Use the "Application Output" window in Debug mode for real-time data monitoring. Set it up properly by following this tutorial.
• UART Terminal - Monitor data via the UART Terminal using a USB to UART converter. For detailed instructions, check out this tutorial.

Additional Notes and Information

The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.

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