Build a simple temperature detector using TMP127 and STM32F107VCT6
Is it too hot or too cold?
Published Feb 28, 2023
Click board™
Thermo 25 Click
Dev Board
EasyMx PRO v7a for STM32
Compiler
NECTO Studio
MCU
STM32F107VCT6
Detects and measures the warmth or coolness of your surroundings
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Hardware Overview
How does it work?
Thermo 25 Click is based on the TMP127-Q1, a factory-calibrated digital output temperature sensor designed for thermal management and thermal protection applications from Texas Instruments. This sensor is characterized by high accuracy and a temperature range of -55°C to +150°C that provides typical ±0.8°C accuracy. It also contains a 14-bit ADC to monitor and digitize the temperature reading to a resolution of 0.03125°C per LSB. The wide supply voltage range, low supply current, and SPI-compatible interface make it ideal for various applications, including process control, environmental monitoring, domestic appliances, and many more. The TMP127-Q1 possesses two operational modes: Continuous-Conversion (CC) and
Shutdown Mode. In the CC mode, ADC performs continuous temperature conversions and stores each result in the temperature register, overwriting the result from the previous conversion. The Shutdown mode reduces power consumption in the TMP127-Q1 when continuous temperature monitoring is not required. The TMP127-Q1 continuously powers up in the Continuous-Conversion mode, while the Shutdown mode can optimize current consumption for low-power applications. This Click board™ communicates with MCU through a standard SPI interface (compatible with SPI or MICROWIRE bus specifications) supporting the two most common SPI modes, SPI Mode 0 and 3,
with a maximum frequency of 10MHz. The SPI interface features a simplified no-register map protocol with a read-write 4-wire configuration. Writing to the TMP127-Q1 will allow the system to use the Shutdown mode and read the device ID. 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. However, the 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
EasyMx PRO v7a for STM32 is the seventh generation of ARM development boards specially designed to develop embedded applications rapidly. It supports a wide range of 32-bit ARM microcontrollers from STMicroelectronics and a broad set of unique functions, such as the first-ever embedded debugger/programmer over USB-C. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. With two different connectors for each port, EasyMx PRO v7afor STM32 allows you to connect accessory boards, sensors, and custom electronics more efficiently than ever. Each part of the EasyMx
PRO v7a for STM32 development board contains the components necessary for the most efficient operation of the same board. In addition to the advanced integrated CODEGRIP programmer/debugger module, which offers many valuable programming/debugging options and seamless integration with the Mikroe software environment, the board also includes a clean and regulated power supply block for the development board. It can use a wide range of external power sources, including an external 12V power supply, 7-23V AC or 9-32V DC via DC connector/screw terminals, and a power source via the USB Type-C (USB-C) connector. Communication options such as USB-UART, USB-HOST/DEVICE, CAN, and
Ethernet are also included, including the well-established mikroBUS™ standard, one display option for the TFT board line of products, and a standard TQFP socket for the seventh-generation MCU cards. This socket covers 32-bit ARM MCUs like STM32 Cortex-M3, -M7, and -M4 MCUs. EasyMx PRO v7afor STM32 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development 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
7th Generation
Architecture
ARM Cortex-M3
MCU Memory (KB)
10
Silicon Vendor
STMicroelectronics
Pin count
100
RAM (Bytes)
100
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 EasyMx PRO v7a for STM32 as your development board.
Track your results in real time
Application Output
After pressing the "FLASH" button on the left-side panel, it is necessary to open the UART terminal to display the achieved results. By clicking on the Tools icon in the right-hand panel, multiple different functions are displayed, among which is the UART Terminal. Click on the offered "UART Terminal" icon.
Once the UART terminal is opened, the window takes on a new form. At the top of the tab are two buttons, one for adjusting the parameters of the UART terminal and the other for connecting the UART terminal. The tab's lower part is reserved for displaying the achieved results. Before connecting, the terminal has a Disconnected status, indicating that the terminal is not yet active. Before connecting, it is necessary to check the set parameters of the UART terminal. Click on the "OPTIONS" button.
In the newly opened UART Terminal Options field, we check if the terminal settings are correct, such as the set port and the Baud rate of UART communication. If the data is not displayed properly, it is possible that the Baud rate value is not set correctly and needs to be adjusted to 115200. If all the parameters are set correctly, click on "CONFIGURE".
The next step is to click on the "CONNECT" button, after which the terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.
Software Support
Library Description
This library contains API for Thermo 25 Click driver.
Key functions:
thermo25_check_communicationThis function sets the operating mode to shutdown, then reads and verifies the device ID and switches back to the continuous mode.thermo25_read_temperatureThis function reads the temperature measurements in degrees Celsius.thermo25_set_modeThis function sets the device operating mode to shutdown or continuous mode by using SPI serial interface.
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 main.c
* @brief Thermo 25 Click example
*
* # Description
* This example demonstrates the use of Thermo 25 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 checks the communication by setting the operating mode
* to shutdown, reading and verifying the device ID, and switching back to the continuous mode.
*
* ## Application Task
* Reads the temperature measurement in degrees Celsius and displays the results on the USB UART
* approximately once per second.
*
* @author Stefan Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "thermo25.h"
static thermo25_t thermo25;
static log_t logger;
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
thermo25_cfg_t thermo25_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.
thermo25_cfg_setup( &thermo25_cfg );
THERMO25_MAP_MIKROBUS( thermo25_cfg, MIKROBUS_1 );
if ( SPI_MASTER_ERROR == thermo25_init( &thermo25, &thermo25_cfg ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
if ( THERMO25_ERROR == thermo25_check_communication ( &thermo25 ) )
{
log_error( &logger, " Check communication." );
for ( ; ; );
}
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
float temperature;
if ( THERMO25_OK == thermo25_read_temperature ( &thermo25, &temperature ) )
{
log_printf ( &logger, " Temperature: %.2f degC\r\n\n", temperature );
Delay_ms ( 1000 );
}
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
