Achieve advanced proximity measurement with TMD2635 and ATmega328P

The dynamic duo for detecting your presence!

Proximity 17 Click with Arduino UNO Rev3

Published Feb 14, 2024

Click board™

Proximity 17 Click

Dev. board

Arduino UNO Rev3

Compiler

NECTO Studio

MCU

ATmega328P

Experience seamless and accurate detection of nearby objects with our state-of-the-art proximity solution, designed to enhance performance and safety in various applications

Hardware Overview

How does it work?

Proximity 17 Click is based on the TMD2635, a miniature close-range proximity sensor module from ams AG. The TMD2635 implements a 940nm infrared VCSEL (Vertical Cavity Surface Emitting Laser) factory calibrated for IR proximity response alongside a digital I2C serial interface. The proximity detection feature provides object detection (e.g., close proximity) by photodiode detection of reflected IR energy sourced by the integrated VCSEL emitter. The proximity engine also features a wide range offset adjustment to compensate for unwanted IR energy reflection at the sensor. The results are further improved by automatic ambient light subtraction. The TMD2635 does not require a specific Power-Up sequence but requires a supply

voltage of 1.8V to work correctly. Therefore, a small regulating LDO, the MAX8511, provides a 1.8V out of selected mikroBUS™ power rail. Also, it can be shut down through software with a low standby current, allowing the power rails to remain powered at all times. Proximity 17 Click communicates with MCU using the standard I2C 2-Wire interface with a maximum clock frequency of 400kHz, fully adjustable through software registers with a 14-bit proximity result stored in a PDATA register. Since the sensor for operation requires a power supply of 1.8V, this Click board™ also features the PCA9306 and SN74LVC1T45 voltage-level translators. The I2C interface bus lines are routed to the voltage-level translators allowing this Click board™

to work with both 3.3V and 5V MCUs properly. Also, it uses an interrupt pin, the INT pin of the mikroBUS™ socket, used when an interrupt occurs to alert the system when proximity result crosses upper or lower threshold settings. 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

Arduino UNO is a versatile microcontroller board built around the ATmega328P chip. It offers extensive connectivity options for various projects, featuring 14 digital input/output pins, six of which are PWM-capable, along with six analog inputs. Its core components include a 16MHz ceramic resonator, a USB connection, a power jack, an

ICSP header, and a reset button, providing everything necessary to power and program the board. The Uno is ready to go, whether connected to a computer via USB or powered by an AC-to-DC adapter or battery. As the first USB Arduino board, it serves as the benchmark for the Arduino platform, with "Uno" symbolizing its status as the

first in a series. This name choice, meaning "one" in Italian, commemorates the launch of Arduino Software (IDE) 1.0. Initially introduced alongside version 1.0 of the Arduino Software (IDE), the Uno has since become the foundational model for subsequent Arduino releases, embodying the platform's evolution.

Microcontroller Overview

MCU Card / MCU

Architecture

AVR

MCU Memory (KB)

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

2048

You complete me!

Accessories

Click Shield for Arduino UNO has two proprietary mikroBUS™ sockets, allowing all the Click board™ devices to be interfaced with the Arduino UNO board without effort. The Arduino Uno, a microcontroller board based on the ATmega328P, provides an affordable and flexible way for users to try out new concepts and build prototypes with the ATmega328P microcontroller from various combinations of performance, power consumption, and features. The Arduino Uno has 14 digital input/output pins (of which six can be used as PWM outputs), six analog inputs, a 16 MHz ceramic resonator (CSTCE16M0V53-R0), a USB connection, a power jack, an ICSP header, and reset button. Most of the ATmega328P 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 Arduino UNO board with our Click Shield for Arduino UNO, 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

Interrupt

PC3

INT

I2C Clock

PC5

SCL

I2C Data

PC4

SDA

Power Supply

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

Click Shield for Arduino UNO front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Arduino UNO Rev3 as your development board.

Arduino UNO Rev3 front image hardware assembly

Charger 27 Click front image hardware assembly

Arduino UNO Rev3 Access MB 1 - upright/background 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 Proximity 17 Click driver.

Key functions:

proximity17_get_int_pin This function returns the INT pin logic state.
proximity17_read_proximity This function reads the raw proximity data. The higher the value, the closer the detected object is.
proximity17_soft_reset This function executes the device software reset command.

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 Proximity17 Click example
 *
 * # Description
 * This example demonstrates the use of Proximity 17 click board by reading and 
 * displaying the proximity data on the USB UART.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and logger, and performs the click default configuration.
 *
 * ## Application Task
 * Reads the proximity data and displays it on the USB UART approximately once per second.
 * The higher the proximity value, the closer the detected object is.
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "proximity17.h"

static proximity17_t proximity17;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    proximity17_cfg_t proximity17_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.
    proximity17_cfg_setup( &proximity17_cfg );
    PROXIMITY17_MAP_MIKROBUS( proximity17_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == proximity17_init( &proximity17, &proximity17_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( PROXIMITY17_ERROR == proximity17_default_cfg ( &proximity17 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    uint16_t proximity;
    if ( PROXIMITY17_OK == proximity17_read_proximity ( &proximity17, &proximity ) )
    {
        log_printf ( &logger, " Proximity: %u\r\n\n", proximity );
        Delay_ms ( 1000 );
    }
}

void main ( void ) 
{
    application_init( );

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

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