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Simplify temperature tracking for your convenience and peace of mind using TMP116 and PIC18F47K40

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Temp-Log 2 Click with EasyPIC v7a

Published Nov 07, 2023

Click board™

Temp-Log 2 Click

Development board

EasyPIC v7a

Compiler

NECTO Studio

MCU

PIC18F47K40

We go beyond temperature measurement with added EEPROM memory, ensuring your data is secure and accessible whenever you need it

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Hardware Overview

How does it work?

Temp-Log 2 Click is based on the TMP116, high-accuracy, low-power, digital temperature sensor, from Texas Instruments. The TMP116 utilizes a diode type temperature sensor with an internal sigma-delta 16bit ADC for the temperature measurement and conversion. The device can work in several operating modes that affect the power consumption, as well as the measurement accuracy. Equipped with 16bit ADC, TMP116 provides measurement step of 0.0078125°C. The TMP116 sensor uses the I2C bus for the communication with the MCU. This sensor has six config/data registers, which are used to access all the functions of this device. It also has four additional registers for storing user-specific data in the non-volatile memory area (EEPROM). After initializing the I2C communication with the START condition from the master, a valid device address is expected. This thermal sensor uses the 100100A binary value as the 7bit I2C address, where “A” corresponds to the logical state of the ADDR0 pin. This pin can be set to a HIGH or a LOW logic state by switching the position of the onboard SMD jumper, labeled as ADDR SEL. The TMP116 sensor is made with the power saving in mind. When the Shutdown mode is engaged, the power consumption is minimal and most of the device sections are not consuming any power. One Shot mode allows to wake up the device, take one measurement, update the registers, and revert to the Shutdown mode again. This allows for a minimum power consumption. To allow One Shot mode, the device needs to be put into the

Shutdown mode first. The most power is consumed by the Continuous mode. This mode allows setting the integration and the standby time. Integration time actively burst-samples the thermal data, reducing the noise error by averaging the result. Allowing longer stand-by duration prevents too much power consumption, as well as the additional self-heating of the sensor IC which would affect the accuracy of the measurement. The 16bit Configuration register is used to configure all the working parameters of the sensor: working mode (one-shot mode, continuous conversion mode, and shutdown mode), measurement conversion and integration parameters, the polarity of the ALERT pin, DATA_RDY status, non-volatile memory busy status, and so on. There is also a copy of this register in the non-volatile memory, which can be independently changed. After the power on, the content of the non-volatile Configuration register will be copied to its volatile counterpart allowing settings retention, even after power down. To write data to the non-volatile memory locations, it is necessary to first unlock the EUN lock bit in the EEPROM Unlock register. After the EEPROM unlock, it is possible to write in the EEPROM locations. Four general purpose EEPROM register locations can be used for storing any type of data. Writing data to the configuration registers will mirror the data to the respective EEPROM locations. EEPROM Unlock register also contains the EEPROM_Busy bit, which indicates the readiness of the EEPROM. If this bit is 0, the

writing to EEPROM is possible. This bit mirrors the same bit in the Configuration register. There are two more 16bit registers used to set the high and low temperature threshold, which also have their non-volatile copies. Depending on the ALERT mode bit in the Configuration register, the temperature threshold values in these registers will be used to trigger an event on the ALERT pin, routed to the mikroBUS™ INT pin. This pin is pulled HIGH on this Click board™ by a resistor, so it is a good idea to configure it as active LOW, by using the polarity bit in the Configuration register. The TMP116 device contains a register with the unique device ID, which is factory programmed to read only locations. Additionally, the general purpose EEPROM registers are pre-programmed with one more unique ID, which allows NIST traceability. The TMP116 units are 100% tested on a production setup that is NIST traceable and verified with equipment that is calibrated to ISO/IEC 17025 accredited standards. If the NIST traceability is not required, general purpose EEPROM registers can be freely overwritten. MikroElektronika provides libraries and functions which simplify working with this device. For more detailed information on the functionality of this device, TMP116 datasheet can be consulted. Temp-Log 2 click is capable of working with both 3.3V and 5V systems. The desired operational voltage can be selected by the VCC SEL SMD jumper. SCL and SDA lines are both pulled HIGH by the onboard resistors, so the Temp-Log 2 click is ready to be used right out of the box.

Temp-Log 2 Click hardware overview image

Features overview

Development board

EasyPIC v7a is the seventh generation of PIC development boards specially designed for the needs of rapid development of embedded applications. It supports a wide range of 8-bit PIC microcontrollers from Microchip and has 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 in one place, such as switches, buttons, indicators, connectors, and others. With four different connectors for each port, EasyPIC v7a allows you to connect accessory boards, sensors, and custom electronics more efficiently than ever. Each part of the EasyPIC v7a 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 module for the development board. It can use various 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 and RS-232 are also included, alongside the well-

established mikroBUS™ standard, three display options (7-segment, graphical, and character-based LCD), and several different DIP sockets. These sockets cover a wide range of 8-bit PIC MCUs, from PIC10F, PIC12F, PIC16F, PIC16Enh, PIC18F, PIC18FJ, and PIC18FK families. EasyPIC v7a 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.

EasyPIC v7a double side image

Microcontroller Overview

MCU Card / MCU

PIC18F47K40

Architecture

PIC

MCU Memory (KB)

128

Silicon Vendor

Microchip

Pin count

40

RAM (Bytes)

3728

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
NC
NC
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Alert Interrupt
RB0
INT
NC
NC
TX
NC
NC
RX
I2C Clock
RC3
SCL
I2C Data
RC4
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Schematic

Temp-Log 2 Click Schematic schematic

Step by step

Project assembly

EasyPIC v7a front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyPIC v7a as your development board.

EasyPIC v7a front image hardware assembly
Buck 22 Click front image hardware assembly
MCU DIP 40 hardware assembly
EasyPIC v7a MB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
NECTO Compiler Selection Step Image hardware assembly
NECTO Output Selection Step Image hardware assembly
Necto image step 6 hardware assembly
Necto DIP image step 7 hardware assembly
EasyPIC PRO v7a Display Selection Necto Step hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto PreFlash Image hardware assembly

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.

UART Application Output Step 1

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.

UART Application Output Step 2

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".

UART Application Output Step 3

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.

UART Application Output Step 4

Software Support

Library Description

This library contains API for Temp-Log 2 Click driver.

Key functions:

  • templog2_write_reg - Write Register function.

  • templog2_read_reg - Read Register function.

  • templog2_read_temp - Read Temperature function.

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 Temp-Log 2 Click example
 *
 * # Description
 * This example demonstrates the use of the Temp-Log 2 Click board.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes peripherals and pins.
 * Initializes I2C driver and performs device configuration.
 * Sets total active conversion time to 250 ms and 8 average samples.
 * Also sets Shutdown Mode as default mode, and after device reset puts device
 * in Continuous Conversion Mode.
 * High limit status will be set when temperature cross over the determined
 * high limit temperature value.
 * Low limit status will be set when temperature falls below the determined
 * low limit temperature value.
 *
 * ## Application Task
 * Reads temperature value calculated to Celsius degrees.
 *
 * \author Nemanja Medakovic
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "templog2.h"


// ------------------------------------------------------------------ VARIABLES

static templog2_t templog2;
static log_t logger;

// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init( void )
{
    templog2_cfg_t templog2_cfg;
    log_cfg_t log_cfg;

    //  Click initialization.
    templog2_cfg_setup( &templog2_cfg );
    TEMPLOG2_MAP_MIKROBUS( templog2_cfg, MIKROBUS_1 );
    templog2_init( &templog2, &templog2_cfg );

    //  Click default configuration.
    templog2_default_config( &templog2 );

    /** 
     * 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, "----  Temp-Log 2 Application Init Done  ----\r\n" );
}

void application_task( void )
{
    float temperature;
    uint8_t temp_status;
    uint8_t cnt;

    temp_status = templog2_data_ready( &templog2 );

    if (temp_status & TEMPLOG2_DATA_READY_MASK)
    {
        temperature = templog2_read_temp( &templog2 );

        log_printf( &logger, " > Temperature : %.2f\r\n", temperature );

        if (temp_status & TEMPLOG2_LOW_LIMIT_MASK)
        {
            log_printf( &logger, " LOW LIMIT DETECTED!\r\n" );
        }

        if (temp_status & TEMPLOG2_HIGH_LIMIT_MASK)
        {
            log_printf( &logger, " HIGH LIMIT DETECTED!\r\n" );
        }
    }
}

void main( void )
{
    application_init( );

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

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

Additional Support

Resources