Intermediate
30 min

Explore the endless potential of proximity detection with TMD3719 and STM32F091RC

Proximity sensing: Creating smarter and safer environments

Proximity 12 Click with Nucleo-64 with STM32F091RC MCU

Published Feb 26, 2024

Click board™

Proximity 12 Click

Dev. board

Nucleo-64 with STM32F091RC MCU

Compiler

NECTO Studio

MCU

STM32F091RC

With proximity detection, we're unlocking the doors to a world where automation and personalization combine to enhance every moment

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Hardware Overview

How does it work?

Proximity 12 Click is based on the TMD3719, an optical sensor that integrates ambient light sensing, proximity detection, and flicker detection sensing from ams OSRAM. The ambient light and color sensing function provide six concurrent ambient light sensing channels: Red, Green, Blue, Clear, Leakage, and Wideband, which accurately measure ambient light and calculate illuminance, chromaticity, and color temperature. The TMD3719 also integrates direct detection of ambient light flicker for four selectable frequency bins, executed parallel with ambient light and color sensing. The proximity function synchronizes IR emission and detection to sense nearby objects. This function features self-maximizing dynamic range, ambient light subtraction, and advanced cross-talk cancelation. The proximity engine recognizes

detect/release events and produces a configurable interrupt, routed to the INT pin of the mikroBUS™ socket, whenever the proximity result crosses upper or lower threshold settings. Proximity 12 Click communicates with MCU using the standard I2C 2-Wire interface with a maximum clock frequency of up to 400kHz. In addition to I2C communication, several GPIO pins connected to the mikroBUS™ socket pins are also used. The SYN pin, routed to the CS pin of the mikroBUS™ socket, is used to synchronize data and allows the start of the classic ambient light, proximity sensing, and flicker detection with every new SYN signal instead of immediately. It also has two pins labeled GP1 and GP2, routed on the RST and PWM pins of the mikroBUS™ socket, used as general-purpose pins, more precisely, GP1 as open-drain

general-purpose input/output and GP2 only as an input pin. The TMD3719 requires a supply voltage of 1.8V to work correctly. Therefore, a small regulating LDO, the BH18PB1WHFV from Rohm Semiconductor, provides a 1.8V out of 3.3V mikroBUS™ rail. The LDO cuts power consumption by lowering its current consumption to approximately 2μA when the application operates in the Standby state. 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.

Proximity 12 Click top side image
Proximity 12 Click bottom side image

Features overview

Development board

Nucleo-64 with STM32F091RC 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 STM32F091RC MCU double side image

Microcontroller Overview

MCU Card / MCU

default

Architecture

ARM Cortex-M0

MCU Memory (KB)

256

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.

Click Shield for Nucleo-64 accessories 1 image

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
General-Purpose I/O
PC12
RST
Data Sync
PB12
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
General-Purpose I/O
PC8
PWM
Interrupt
PC14
INT
NC
NC
TX
NC
NC
RX
I2C Clock
PB8
SCL
I2C Data
PB9
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Click board™ Schematic

Proximity 12 Click Schematic schematic

Step by step

Project assembly

Click Shield for Nucleo-64 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Nucleo-64 with STM32F091RC MCU as your development board.

Click Shield for Nucleo-64 front image hardware assembly
Nucleo 64 with STM32F401RE MCU front image hardware assembly
EEPROM 13 Click front image hardware assembly
Prog-cut hardware assembly
Nucleo-64 with STM32XXX MCU MB 1 Mini B Conn - 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
Clicker 4 for STM32F4 HA MCU 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

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 Proximity 12 Click driver.

Key functions:

  • proximity12_read_proximity - This function reads the raw proximity value measured by the click board.

  • proximity12_read_als - This function reads all als data measured by the click board.

  • proximity12_set_led_isink - This function sets the LEDs sink scaler and current values.

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 Proximity12 Click example
 *
 * # Description
 * This function demonstrates the use of Proximity 12 click board.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and performs the click default configuration.
 *
 * ## Application Task
 * Reads the proximity and ALS values and displays the results on the USB UART 
 * approximately every 100ms.
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "proximity12.h"

static proximity12_t proximity12;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;                  /**< Logger config object. */
    proximity12_cfg_t proximity12_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 );
    Delay_ms( 100 );
    log_info( &logger, " Application Init " );

    // Click initialization.
    proximity12_cfg_setup( &proximity12_cfg );
    PROXIMITY12_MAP_MIKROBUS( proximity12_cfg, MIKROBUS_1 );
    err_t init_flag = proximity12_init( &proximity12, &proximity12_cfg );
    if ( I2C_MASTER_ERROR == init_flag ) 
    {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );
    }
    Delay_ms( 100 );
    
    init_flag = proximity12_default_cfg ( &proximity12 );
    if ( PROXIMITY12_ERROR == init_flag ) 
    {
        log_error( &logger, " Default Cfg Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );
    }
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    uint16_t prox_data = 0;
    proximity12_als_data_t als;
    err_t error_flag = proximity12_read_proximity ( &proximity12, &prox_data );
    error_flag |= proximity12_read_als ( &proximity12, &als );

    if ( PROXIMITY12_OK == error_flag )
    {
        log_printf( &logger, " - Proximity data -\r\n" );
        log_printf( &logger, " Proximity: %u\r\n", prox_data );
        log_printf( &logger, " - ALS data -\r\n" );
        log_printf( &logger, " Clear: %lu - Red: %lu - Green: %lu - Blue: %lu\r\n", als.clear,
                                                                                    als.red,
                                                                                    als.green, 
                                                                                    als.blue );
        
        log_printf( &logger, " Leakage: %lu - Wideband: %lu - IR1: %lu - IR2: %lu\r\n\r\n", als.leakage,
                                                                                            als.wideband,
                                                                                            als.ir1, 
                                                                                            als.ir2 );
    }
    Delay_ms( 100 );
}

void main ( void ) 
{
    application_init( );

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

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

Additional Support

Resources

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