Embrace a smarter and more convenient way of life with HTU21DF and STM32F756ZG
Experience the future of climate control today
Published Nov 08, 2023
Click board™
Temp&Hum 13 Click
Dev Board
UNI Clicker
Compiler
NECTO Studio
MCU
STM32F756ZG
Take control of your surroundings and make data-driven decisions for maximum comfort and productivity.
A
A
Hardware Overview
How does it work?
Temp&Hum 13 Click is based on the HTU21DF, a digital relative humidity sensor with temperature output from TE Connectivity. This sensor is factory calibrated to ±2% relative humidity and ±0.3°C temperature accuracy. It has an integrated heating element that is used for functionality diagnosis as well. This heating element can be simply activated by setting a bit in the appropriate register. In the case when the heater is powered on, the typical power consumption is about 5.5mW. Internally, two sensors are connected to the two separated ADC sections with variable resolution of 12 -14 bits for the temperature and 8-12 bits for relative humiditiy measurement. The OTP memory holds the calibration coefficients that are applied to the measured value and the results are stored on the output registers, in the MSB/LSB format. These values are then used in formulas found in the HTU21DF datasheet so that the final temperature or relative humidity data can be
calculated. It is also possible to correct the offsets with custom values. Temp&Hum 13 click uses the I2C protocol to communicate with the host MCU. Its I2C bus pins are routed to the mikroBUS™ I2C pins and are pulled to a HIGH logic level by the onboard resistors. The final I2C address of this IC is factory determined. There are two different operation modes to communicate with the HTU21D sensor: Hold Master mode and No Hold Master mode. In the first case, the SCK line is blocked (controlled by HTU21D(F) sensor) during measurement process while in the second case the SCK line remain open for other communication while the sensor is processing the measurement. The HTU21DF IC itself is a very low power consumption device and it can work in two modes: sleep and active (measurement) mode. The device enters the sleep the mode as soon as possible, to save power. This makes the HTU21DF suitable to be used in battery-powered applications. In these
applications, the HTU21DF spends most of the time in sleep mode, with the typical current consumption of 20 nA. While in the active mode, the typical current consumption is 450µA. The provided Click board™ library contains simple and easy to use functions, which simplify configuring and reading of the measurement data. These functions are demonstrated in the included example application and can be used as a reference for custom projects. These functions can be used in mikroC, mikroBasic and mikroPascal compilers for all MCU architectures, supported by MikroElektronika. This Click Board™ is designed to be operated only with 3.3V logic level. A proper logic voltage level conversion should be performed before the Click board™ is used with MCUs with logic levels of 5V. It is ready to be used as soon as it is inserted into a mikroBUS™ socket of the development system.
Features overview
Development board
UNI Clicker is a compact development board designed as a complete solution that brings the flexibility of add-on Click boards™ to your favorite microcontroller, making it a perfect starter kit for implementing your ideas. It supports a wide range of microcontrollers, such as different ARM, PIC32, dsPIC, PIC, and AVR from various vendors like Microchip, ST, NXP, and TI (regardless of their number of pins), four mikroBUS™ sockets for Click board™ connectivity, a USB connector, LED indicators, buttons, a debugger/programmer connector, and two 26-pin headers for interfacing with external electronics. Thanks to innovative manufacturing technology, it allows you to build
gadgets with unique functionalities and features quickly. Each part of the UNI Clicker development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the UNI Clicker programming method, using a third-party programmer or CODEGRIP/mikroProg connected to onboard JTAG/SWD header, the UNI Clicker board also includes a clean and regulated power supply module for the development kit. It provides two ways of board-powering; through the USB Type-C (USB-C) connector, where onboard voltage regulators provide the appropriate voltage levels to each component on the board, or using a Li-Po/Li
Ion battery via an onboard battery connector. All communication methods that mikroBUS™ itself supports are on this board (plus USB HOST/DEVICE), including the well-established mikroBUS™ socket, a standardized socket for the MCU card (SiBRAIN standard), and several user-configurable buttons and LED indicators. UNI Clicker is an integral part of the Mikroe ecosystem, allowing you to create a new application in minutes. Natively supported by Mikroe software tools, it covers many aspects of prototyping thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.
Microcontroller Overview
MCU Card / MCU
Type
8th Generation
Architecture
ARM Cortex-M7
MCU Memory (KB)
1024
Silicon Vendor
STMicroelectronics
Pin count
144
RAM (Bytes)
327680
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the UNI Clicker as your development board.
Track your results in real time
Application Output via Debug Mode
1. Once the code example is loaded, pressing the "DEBUG" button initiates the build process, programs it on the created setup, and enters Debug mode.
2. After the programming is completed, a header with buttons for various actions within the IDE becomes visible. Clicking the green "PLAY" button starts reading the results achieved with the Click board™. The achieved results are displayed in the Application Output tab.
Software Support
Library Description
This library contains API for Temp&Hum 13 Click driver.
Key functions:
temphum13_get_humidity- This function calculates humidity.temphum13_get_temperature-This function calculates current temperature.temphum13_change_resolution- This function sets click measurement resolution.
Open Source
Code example
This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.
/*!
* \file
* \brief TempHum13 Click example
*
* # Description
* This demo shows basic TempHum13 click functionality - temperature
* and humidity measurement.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initialize device.
*
* ## Application Task
* Measure temperature and humidity values on every 0,5 seconds,
* and log them to UART Terminal if they are valid.
*
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "temphum13.h"
// ------------------------------------------------------------------ VARIABLES
static temphum13_t temphum13;
static log_t logger;
static float temperature;
static float humidity;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
temphum13_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.
temphum13_cfg_setup( &cfg );
Delay_ms(500);
TEMPHUM13_MAP_MIKROBUS( cfg, MIKROBUS_1 );
Delay_ms(500);
temphum13_init( &temphum13, &cfg );
Delay_ms(500);
temphum13_default_cfg( &temphum13 );
}
void application_task ( void )
{
temperature = temphum13_get_temperature( &temphum13 );
humidity = temphum13_get_humidity( &temphum13 );
if ( temperature != 65536.0 )
{
log_printf( &logger, "\r\n> Temperature : %.2f C", temperature );
}
if ( humidity != 65536.0 )
{
log_printf( &logger, "\r\n> Humidity : %.2f%%RH\r\n", humidity );
}
Delay_ms( 500 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
Additional Support
Resources
Category:Temperature & humidity
