Intermediate
30 min

Experience the efficiency of our 4-20mA current loop solution with DAC161S997 and STM32F031K6

Enhance your process automation

4-20mA T 2 Click with Nucleo 32 with STM32F031K6 MCU

Published Oct 01, 2024

Click board™

4-20mA T 2 Click

Dev Board

Nucleo 32 with STM32F031K6 MCU

Compiler

NECTO Studio

MCU

STM32F031K6

Experience precise signal transmission with our advanced analog current loop transmitter, which provides seamless connectivity and compatibility with various industrial applications

A

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Hardware Overview

How does it work?

4-20mA T 2 Click is based on the DAC161S997, a low-power 16-bit ΣΔ digital-to-analog converter (DAC) from Texas Instruments, realized as a ΣΔ modulator. Next to ΣΔ DAC, the DAC161S997 also contains an internal ultra-low power voltage reference and an internal oscillator to reduce power and component count in compact loop-powered applications. This architecture, where DAC's output current represents a multiplied copy of the filtered modulator output, ensures an excellent linearity performance while minimizing the device's power consumption. In addition to an industry-standard 4-20 mA current loop over the LOOP terminal, the DAC161S997 also has the possibility of a simple Highway Addressable

Remote Transducer (HART) modulator interfacing through an onboard HART TX terminal. It allows the injection of FSK-modulated digital data into the 4-20mA current loop. This Click board™ communicates with MCU using a 4-wire SPI serial interface with a maximum frequency of 10MHz, for data transfer and configuration of the DAC functions. The DAC161S997 supports both Mode 0 and Mode 3 of the SPI protocol. 4-20mA T 2 Click comes with an additional feature, as an interrupt, available on the ERR pin of the mikroBUS™ socket, the loop-error detection/reporting feature. By default, the DAC161S997 detects and reports several types of errors: loop error, SPI timeout error (channel error), frame error, and alarm current. In

the case of a fault condition or during the initial Power-Up sequence, the DAC161S997 will output current in either the upper or lower error current band. The band's choice is user-selectable via the appropriate position of an onboard jumper ERRL SEL, while the current error value is programmable through the SPI interface. This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. Also, it comes equipped with a library containing functions and an example code that can be used, as a reference, for further development.

4-20mA T 2 Click hardware overview image

Features overview

Development board

Nucleo 32 with STM32F031K6 MCU board provides an affordable and flexible platform for experimenting with STM32 microcontrollers in 32-pin packages. Featuring Arduino™ Nano connectivity, it allows easy expansion with specialized shields, while being mbed-enabled for seamless integration with online resources. The

board includes an on-board ST-LINK/V2-1 debugger/programmer, supporting USB reenumeration with three interfaces: Virtual Com port, mass storage, and debug port. It offers a flexible power supply through either USB VBUS or an external source. Additionally, it includes three LEDs (LD1 for USB communication, LD2 for power,

and LD3 as a user LED) and a reset push button. The STM32 Nucleo-32 board is supported by various Integrated Development Environments (IDEs) such as IAR™, Keil®, and GCC-based IDEs like AC6 SW4STM32, making it a versatile tool for developers.

Nucleo 32 with STM32F031K6 MCU double side image

Microcontroller Overview

MCU Card / MCU

default

Architecture

ARM Cortex-M0

MCU Memory (KB)

32

Silicon Vendor

STMicroelectronics

Pin count

32

RAM (Bytes)

4096

You complete me!

Accessories

Click Shield for Nucleo-32 is the perfect way to expand your development board's functionalities with STM32 Nucleo-32 pinout. The Click Shield for Nucleo-32 provides two mikroBUS™ sockets to add any functionality from our ever-growing range of Click boards™. We are fully stocked with everything, from sensors and WiFi transceivers to motor control and audio amplifiers. The Click Shield for Nucleo-32 is compatible with the STM32 Nucleo-32 board, providing an affordable and flexible way for users to try out new ideas and quickly create prototypes with any STM32 microcontrollers, choosing from the various combinations of performance, power consumption, and features. The STM32 Nucleo-32 boards do not require any separate probe as they integrate the ST-LINK/V2-1 debugger/programmer and come with the STM32 comprehensive software HAL library and various packaged software examples. This development platform provides users with an effortless and common way to combine the STM32 Nucleo-32 footprint compatible board with their favorite Click boards™ in their upcoming projects.

Click Shield for Nucleo-32 accessories 1 image

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
SPI Chip Select
PA4
CS
SPI Clock
PB3
SCK
SPI Data OUT
PB4
MISO
SPI Data IN
PB5
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Loop-Error Interrupt
PA12
INT
NC
NC
TX
NC
NC
RX
NC
NC
SCL
NC
NC
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

4-20mA T 2 Click Schematic schematic

Step by step

Project assembly

Click Shield for Nucleo-144 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Nucleo 32 with STM32F031K6 MCU as your development board.

Click Shield for Nucleo-144 front image hardware assembly
Nucleo 144 with STM32L4A6ZG MCU front image hardware assembly
Stepper 22 Click front image hardware assembly
Prog-cut hardware assembly
Stepper 22 Click complete accessories setup image hardware assembly
Nucleo-32 with STM32 MCU Access 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 image step 5 hardware assembly
Necto image step 6 hardware assembly
STM32 M4 Clicker HA MCU/Select Step hardware assembly
Necto No Display image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Debug Image Necto Step hardware assembly

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.

DEBUG_Application_Output

Software Support

Library Description

This library contains API for 4-20mA T 2 Click driver.

Key functions:

  • c420mat2_set_output_current - 4-20mA T 2 set output current function

  • c420mat2_get_status - 4-20mA T 2 set status function

  • c420mat2_set_lower_limit - 4-20mA T 2 set lower limit 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 4-20mA T 2 Click example
 *
 * # Description
 * This example demonstrates the use of 4-20mA T 2 Click board™.
 * This driver provides functions to configure 
 * analog output current transfer over an industry standard 4-20mA current loop.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initialization of SPI module and log UART.
 * After driver initialization, default settings turn on the device.
 *
 * ## Application Task
 * This example demonstrates the use of the 4-20mA T 2 Click board™.
 * This example periodically changes the analog output current transfer 
 * from 4mA to 20mA and display status every 5 seconds.
 * Results are being sent to the UART Terminal, where you can track their changes.
 *
 * @author Nenad Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "c420mat2.h"

static c420mat2_t c420mat2;
static log_t logger;
static c420mat2_status_t status;

void display_status ( void )
{
    log_printf( &logger, " Status: \r\n" );
    if ( C420MAT2_STATUS_ERROR == status.ferr_sts )
    {
        log_printf( &logger, " - A frame error has occurred.\r\n" );
    }
    else
    {
        log_printf( &logger, " - No frame error occurred.\r\n" );
    }

    if ( C420MAT2_STATUS_ERROR == status.spi_timeout_err )
    {
        log_printf( &logger, " - The SPI interface has not received a valid command.\r\n" );
    }
    else
    {
        log_printf( &logger, " - The SPI interface has received a valid command.\r\n" );
    }

    if ( C420MAT2_STATUS_ERROR == status.loop_sts )
    {
        log_printf( &logger, " - A status loop error has occurred.\r\n" );
    }
    else
    {
        log_printf( &logger, " - No status loop error has occurred.\r\n" );
    }

    if ( C420MAT2_STATUS_ERROR == status.curr_loop_sts )
    {
        log_printf( &logger, " - A current loop error is occurring.\r\n" );
    }
    else
    {
        log_printf( &logger, " - No current loop error is occurring.\r\n" );
    }
    log_printf( &logger, " ----------------------------\r\n" );
}

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    c420mat2_cfg_t c420mat2_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.
    c420mat2_cfg_setup( &c420mat2_cfg );
    C420MAT2_MAP_MIKROBUS( c420mat2_cfg, MIKROBUS_1 );
    if ( SPI_MASTER_ERROR == c420mat2_init( &c420mat2, &c420mat2_cfg ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( C420MAT2_ERROR == c420mat2_default_cfg ( &c420mat2 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }

    log_info( &logger, " Application Task " );
    log_printf( &logger, " -----------------------------\r\n" );
    Delay_ms( 100 );
}

void application_task ( void )
{
    if ( C420MAT2_OK == c420mat2_set_output_current( &c420mat2, 4.0 ) )
    {
        log_printf( &logger, " Loop Current:  4.0 mA \r\n" );
        log_printf( &logger, " - - - - - - - - - - - - - - -\r\n" );
        if ( C420MAT2_OK == c420mat2_get_status ( &c420mat2, &status ) )
        {
            display_status( );    
        }
        Delay_ms( 5000 );
    }

    if ( C420MAT2_OK == c420mat2_set_output_current( &c420mat2, 10.0 ) )
    {
        log_printf( &logger, " Loop Current: 10.0 mA \r\n" );
        log_printf( &logger, " - - - - - - - - - - - - - - -\r\n" );
        if ( C420MAT2_OK == c420mat2_get_status ( &c420mat2, &status ) )
        {
            display_status( );    
        }
        Delay_ms( 5000 );
    }

    if ( C420MAT2_OK == c420mat2_set_output_current( &c420mat2, 15.0 ) )
    {
        log_printf( &logger, " Loop Current: 15.0 mA \r\n" );
        log_printf( &logger, " - - - - - - - - - - - - - - -\r\n" );
        if ( C420MAT2_OK == c420mat2_get_status ( &c420mat2, &status ) )
        {
            display_status( );    
        }
        Delay_ms( 5000 );
    }

    if ( C420MAT2_OK == c420mat2_set_output_current( &c420mat2, 20.0 ) )
    {
        log_printf( &logger, " Loop Current: 20.0 mA \r\n" );
        log_printf( &logger, " - - - - - - - - - - - - - - -\r\n" );
        if ( C420MAT2_OK == c420mat2_get_status ( &c420mat2, &status ) )
        {
            display_status( );    
        }
        Delay_ms( 5000 );
    }
}

void main ( void )
{
    application_init( );

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

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

Additional Support

Resources

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