Monitor and signal temperature changes with TMP144 and STM32L073RZ

Master of temperature observation

Thermo 23 Click with Nucleo-64 with STM32L073RZ MCU

Published Feb 26, 2024

Click board™

Thermo 23 Click

Dev. board

Nucleo-64 with STM32L073RZ MCU

Compiler

NECTO Studio

MCU

STM32L073RZ

Digital temperature sensor with highly accurate and reliable results

Hardware Overview

How does it work?

Thermo 23 Click is based on the TMP144, a digital temperature sensor that is optimal for thermal management and profiling applications from Texas Instruments. This temperature sensor is characterized by high accuracy; a temperature range of -10°C to +100°C provides typical ±0.5°C accuracy. The temperature sensing device for the TMP144 is the chip itself. A bipolar junction transistor inside the chip is used in a band-gap configuration to produce a voltage proportional to the chip temperature. The voltage is digitized and converted to a 12-bit temperature result in degrees Celsius, with a resolution of 0.0625°C. The TMP144 possesses several operational modes: Continuous-Conversion mode (CC), Shutdown, One-shot mode, and Extended Temperature mode, which increases the temperature-measurement range from -40°C to +120°C. In the CC mode, ADC performs continuous temperature conversions

and stores each result to the temperature register, overwriting the result from the previous conversion, while Shutdown modes reduce power consumption in the TMP75C when continuous temperature monitoring is not required, typically less than 0.5μA. Also, while the TMP144 is in Shutdown mode, it can perform a one-shot temperature measurement and return to the Shutdown state after the single conversion. Thermo 23 Click communicates with MCU using the UART interface with commonly used UART RX and TX pins as its communication protocol operating at 115200bps by default configuration to transmit and exchange data with the host MCU. This interface can also be seen as both UART and SMAART Wire™ interface, supporting daisy-chain configurations. Besides, the interface also supports Multiple Device Access (MDA) commands that let the host communicate with multiple devices on the bus simultaneously.

This sensor's special and equally important feature is its software interrupt, a temperature alert function that monitors the device temperature and compares the result to the values stored in the temperature limit registers to determine if the device temperature is within these set limits. The TMP144 only issues future interrupts once the user-writes sets the interrupt enable bit in the configuration register to re-enable future interrupts. This Click board™ can only be operated with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used as a reference for further development.

Features overview

Development board

Nucleo-64 with STM32L073RZ 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.

Nucleo 64 with STM32L073RZ MCU double side image

Microcontroller Overview

MCU Card / MCU

Architecture

ARM Cortex-M0

MCU Memory (KB)

192

Silicon Vendor

STMicroelectronics

Pin count

RAM (Bytes)

20480

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

RST

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

PWM

INT

UART TX

PA2

UART RX

PA3

SCL

SDA

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

Click Shield for Nucleo-64 accessories 1 image hardware assembly

Start by selecting your development board and Click board™. Begin with the Nucleo-64 with STM32L073RZ MCU as your development board.

Nucleo 64 with STM32F401RE MCU front image hardware assembly

LTE IoT 5 Click front image hardware assembly

Nucleo-64 with STM32XXX MCU Access MB 1 Mini B Conn - upright/background hardware assembly

Clicker 4 for STM32F4 HA MCU Step hardware assembly

Necto No Display image step 8 hardware assembly

Debug Image Necto Step hardware assembly

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 Thermo 23 Click driver.

Key functions:

thermo23_set_config This function sets the configuration register.
thermo23_read_temperature This function reads the temperature value in Celsius.
thermo23_read_command This function reads data from the selected command by using UART serial interface.

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 Thermo 23 Click Example.
 *
 * # Description
 * This example demonstrates the use of Thermo 23 click board by reading and displaying
 * the temperature measurements.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and logger, and performs the click default configuration which enables
 * continuous conversion and sets the conversion rate to 1 Hz.
 *
 * ## Application Task
 * Reads the temperature measurement in Celsius and displays the results on the USB UART
 * approximately once per second.
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "thermo23.h"

static thermo23_t thermo23;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    thermo23_cfg_t thermo23_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.
    thermo23_cfg_setup( &thermo23_cfg );
    THERMO23_MAP_MIKROBUS( thermo23_cfg, MIKROBUS_1 );
    if ( UART_ERROR == thermo23_init( &thermo23, &thermo23_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( THERMO23_ERROR == thermo23_default_cfg ( &thermo23 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    float temperature;
    if ( THERMO23_OK == thermo23_read_temperature ( &thermo23, &temperature ) ) 
    {
        log_printf( &logger, " Temperature : %.2f C\r\n\n", temperature );
        Delay_ms ( 1000 );
    }
}

void main ( void ) 
{
    application_init( );

    for ( ; ; ) 
    {
        application_task( );
    }
}

// ------------------------------------------------------------------------ END