Ensure your space remains cozy and balanced with Si7034 and STM32G474RE
Measure the elements that matter most for a healthier environment
Published Nov 08, 2024
Click board™
Temp&Hum 2 Click
Dev Board
Nucleo 64 with STM32G474RE MCU
Compiler
NECTO Studio
MCU
STM32G474RE
Our mission is to empower you with precise temperature and humidity measurements, ensuring that you can effortlessly maintain a balanced, comfortable, and eco-conscious living or working space
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Hardware Overview
How does it work?
Temp&Hum 2 Click is based on the Si7034, a digital humidity and temperature sensor IC with I2C interface, from Silicon Labs. It is a digital relative humidity and a temperature sensor that integrates temperature and humidity sensor elements, an analog-to-digital converter, signal processing, calibration, and data correction on the chip. Each chip is factory calibrated, and the calibration data is stored in its non-volatile memory. The maximum accuracy achieved with this sensor is ± 4% RH for the humidity range from 0 to 80%. Besides the humidity sensing element, this sensor includes an accurate thermal sensor, which can achieve up to ±0.4 °C. It is used in conjunction with the humidity measurement, to allow thermal compensation of the relative humidity measurements. This sensor IC also has an integrated heating element that is used to evaporate condensation reducing the effect of the offset accumulation when used in high humidity conditions, or to implement dew-point
measurement when the Si7034 is used with a separate temperature sensor. The heating element current can be adjusted by the appropriate bits in the Humidity Control Register. Due to the nature of the used sensors, a special care should be taken to reduce the sensor contamination to a minimum. Particles, dirt or other artifacts collected on the surface of the exposed polymer film will affect its ability to measure the humidity, and therefore, the manufacturer recommends protecting the sensor against particles. The sensor otherwise has a long aging period with minimal drift. Synthetic long-term stability tests show less than 0.25 %RH per year drift. The data provided by the IC is ready to be used directly. Two measurements are done when a command is received via the I2C. One is the humidity measurement, while the second is temperature measurement, used for the compensation. Si7034 IC operates on 1.8V and therefore, a small LDO has to be used to convert 3.3V from the mikroBUS™
power rail, down to 1.8V. In addition, the I2C signal voltage levels also have to be converted so it can be used with the MCUs operated with 3.3V. For this purpose, the Click board™ utilizes the PCA9306, a level shifting IC, made by Texas Instruments. It uses 1.8V as the first reference voltage and 3,3V from the mikroBUS™ power rail as the second reference voltage, shifting the I2C communication signal levels, allowing this Click board™ to be used with MCUs operated at 3.3V. The sensor IC is physically located away from other components on the Click board™, so the heating influence of the surrounding components or PCB is reduced to a minimum, allowing the accuracy of the Click board™ to stay within the specifications. The i2C lines of the IC are routed to the mikroBUS™ and supplied by the pull-up resistors, allowing this Click board™ to be used right out of the box. Temp&Hum 2 click uses only 3.3V rail from the mikroBUS™.
Features overview
Development board
Nucleo-64 with STM32G474R MCU offers a cost-effective and adaptable platform for developers to explore new ideas and prototype their designs. This board harnesses the versatility of the STM32 microcontroller, enabling users to select the optimal balance of performance and power consumption for their projects. It accommodates the STM32 microcontroller in the LQFP64 package and includes essential components such as a user LED, which doubles as an ARDUINO® signal, alongside user and reset push-buttons, and a 32.768kHz crystal oscillator for precise timing operations. Designed with expansion and flexibility in mind, the Nucleo-64 board features an ARDUINO® Uno V3 expansion connector and ST morpho extension pin
headers, granting complete access to the STM32's I/Os for comprehensive project integration. Power supply options are adaptable, supporting ST-LINK USB VBUS or external power sources, ensuring adaptability in various development environments. The board also has an on-board ST-LINK debugger/programmer with USB re-enumeration capability, simplifying the programming and debugging process. Moreover, the board is designed to simplify advanced development with its external SMPS for efficient Vcore logic supply, support for USB Device full speed or USB SNK/UFP full speed, and built-in cryptographic features, enhancing both the power efficiency and security of projects. Additional connectivity is
provided through dedicated connectors for external SMPS experimentation, a USB connector for the ST-LINK, and a MIPI® debug connector, expanding the possibilities for hardware interfacing and experimentation. Developers will find extensive support through comprehensive free software libraries and examples, courtesy of the STM32Cube MCU Package. This, combined with compatibility with a wide array of Integrated Development Environments (IDEs), including IAR Embedded Workbench®, MDK-ARM, and STM32CubeIDE, ensures a smooth and efficient development experience, allowing users to fully leverage the capabilities of the Nucleo-64 board in their projects.
Microcontroller Overview
MCU Card / MCU
Architecture
ARM Cortex-M4
MCU Memory (KB)
512
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
128k
You complete me!
Accessories
Click Shield for Nucleo-64 comes equipped with two proprietary mikroBUS™ sockets, allowing all the Click board™ devices to be interfaced with the STM32 Nucleo-64 board with no effort. This way, Mikroe allows its users to add any functionality from our ever-growing range of Click boards™, such as WiFi, GSM, GPS, Bluetooth, ZigBee, environmental sensors, LEDs, speech recognition, motor control, movement sensors, and many more. More than 1537 Click boards™, which can be stacked and integrated, are at your disposal. The STM32 Nucleo-64 boards are based on the microcontrollers in 64-pin packages, a 32-bit MCU with an ARM Cortex M4 processor operating at 84MHz, 512Kb Flash, and 96KB SRAM, divided into two regions where the top section represents the ST-Link/V2 debugger and programmer while the bottom section of the board is an actual development board. These boards are controlled and powered conveniently through a USB connection to program and efficiently debug the Nucleo-64 board out of the box, with an additional USB cable connected to the USB mini port on the board. Most of the STM32 microcontroller pins are brought to the IO pins on the left and right edge of the board, which are then connected to two existing mikroBUS™ sockets. This Click Shield also has several switches that perform functions such as selecting the logic levels of analog signals on mikroBUS™ sockets and selecting logic voltage levels of the mikroBUS™ sockets themselves. Besides, the user is offered the possibility of using any Click board™ with the help of existing bidirectional level-shifting voltage translators, regardless of whether the Click board™ operates at a 3.3V or 5V logic voltage level. Once you connect the STM32 Nucleo-64 board with our Click Shield for Nucleo-64, you can access hundreds of Click boards™, working with 3.3V or 5V logic voltage levels.
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 Nucleo 64 with STM32G474RE MCU 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 2 Click driver.
Key functions:
temhum2_get_eletronic_id- This function for reads Eletronic IDtemphum2_set_mode- Functions for set measurement modetemphum2_get_measurement- Functions for mesurement
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 TempHum2 Click example
*
* # Description
* This application measures temperature and humidity.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes driver init, set work mode and Heater
*
* ## Application Task
* Reads temperature and humidity and logs values on usbuart for every 500ms.
*
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "temphum2.h"
// ------------------------------------------------------------------ VARIABLES
static temphum2_t temphum2;
static log_t logger;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
temphum2_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.
temphum2_cfg_setup( &cfg );
TEMPHUM2_MAP_MIKROBUS( cfg, MIKROBUS_1 );
temphum2_init( &temphum2, &cfg );
temphum2_default_cfg( &temphum2 );
}
void application_task ( void )
{
float data_buffer[ 2 ];
temphum2_get_measurement( &temphum2, &data_buffer[ 0 ] );
log_printf( &logger, " --- Temperature : %.2f C \r\n ", data_buffer[ 0 ] );
log_printf( &logger, " --- Humidity : %.2f RH \r\n ", data_buffer[ 1 ] );
Delay_ms( 500 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
