Ensure the highest standards of precision in pressure monitoring with MLX90817 and STM32F410RB
Your partner for reliable results in challenging environments
Published Oct 08, 2024
Click board™
Pressure 19 Click
Dev. board
Nucleo 64 with STM32F410RB MCU
Compiler
NECTO Studio
MCU
STM32F410RB
Maximize your project's potential with our cutting-edge digital pressure measurement solution, setting unprecedented benchmarks in both reliability and performance
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Hardware Overview
How does it work?
Pressure 19 Click is based on the MLX90817, a factory-calibrated absolute pressure sensor delivering ratiometric analog output from Melexis Technologies. The MLX90817 absolute pressure sensor includes a sensing element, analog-to-digital converter, signal processing part, and digital interface that sends the digital pressure data to the host controller. It measures pressure from 0.2 to 3bar with an accuracy of ±33mbar over a wide operating temperature range at the industry’s lowest power. The MLX90817 contains a pressure-sensing element consisting of a diaphragm that reacts to a change in absolute pressure, realized in the silicon chip by wafer bonding on an etched cavity with a built-in reference vacuum. The internal strain increases, in particular at the border of the diaphragm, where piezo-resistive elements have been implanted into
the silicon diaphragm, forming a Wheatstone bridge, which acts as a transducer. The front end amplifies the signal from the bridge and performs a coarse offset compensation and an ADC conversion. Then, the DSP executes the compensations over temperature. Furthermore, the digital circuit provides some filtering, the possibility to linearize the pressure signal, and implements the clamping function, delivering an analog output proportional to the pressure. The analog output voltage of the MLX90817 can be converted to a digital value using MCP3221, a successive approximation A/D converter from Microchip, using a 2-wire I2C compatible interface, or can be sent directly to an analog pin of the mikroBUS™ socket labeled as AN. Selection can be performed by onboard SMD jumper labeled AD SEL to an appropriate position marked as AN and
ADC. Using MCP3221 and I2C interface, data transfers at 100kbit/s in the Standard and 400kbit/s in the Fast Mode. Since the sensor for operation requires a 5V logic voltage level only, this Click board™ also features the PCA9306 voltage-level translator from Texas Instruments. The I2C interface bus lines are routed to the dual bidirectional voltage-level translator, allowing this Click board™ to work properly with both 3.3V and 5V MCUs. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used as a reference for further development.
Features overview
Development board
Nucleo-64 with STM32F410RB 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)
128
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
32768
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
Click board™ Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Nucleo 64 with STM32F410RB MCU as your development board.
Track your results in real time
Application Output
1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.
2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.
3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.
Software Support
Library Description
This library contains API for Pressure 19 Click driver.
Key functions:
pressure19_get_pressure- This function reads the output voltage and converts it to pressure in mBarpressure19_read_voltage- This function reads raw ADC value and converts it to proportional voltage levelpressure19_set_vref- This function sets the voltage reference for Pressure 19 click driver
Open Source
Code example
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.
/*!
* @file main.c
* @brief Pressure 19 Click Example.
*
* # Description
* This example demonstrates the use of Pressure 19 click board by reading and
* displaying the absolute pressure value in mBar.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver and logger.
*
* ## Application Task
* Reads and displays the absolute pressure value [mBar] on the USB UART approximately
* once per seconds.
*
* @author Stefan Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "pressure19.h"
static pressure19_t pressure19; /**< Pressure 19 Click driver object. */
static log_t logger; /**< Logger object. */
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
pressure19_cfg_t pressure19_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.
pressure19_cfg_setup( &pressure19_cfg );
PRESSURE19_MAP_MIKROBUS( pressure19_cfg, MIKROBUS_1 );
err_t init_flag = pressure19_init( &pressure19, &pressure19_cfg );
if ( ( ADC_ERROR == init_flag ) || ( I2C_MASTER_ERROR == init_flag ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
uint16_t pressure;
if ( PRESSURE19_OK == pressure19_get_pressure ( &pressure19, &pressure ) )
{
log_printf( &logger, " Pressure : %u mBar\r\n\n", pressure );
Delay_ms( 1000 );
}
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
