Intermediate
30 min
0

Perform accurate distance measurements using VL53L4CX and STM32F103RC

Keep your target in sight

LightRanger 10 Click with UNI Clicker

Published Mar 09, 2023

Click board™

LightRanger 10 Click

Development board

UNI Clicker

Compiler

NECTO Studio

MCU

STM32F103RC

Detect the distance of an object, regardless of its color and reflectance

A

A

Hardware Overview

How does it work?

LightRanger 10 Click is based on the VL53L4CX, a ToF (Time-of-Flight) optical distance sensor with an extended target detection range from STMicroelectronics. This ToF sensor integrates a VCSEL (vertical-cavity surface-emitting laser), emitting an entirely invisible 940nm IR light, which is totally safe for eyes (Class 1 certification). Also, there is a SPAD (single-photon avalanche diode) array which helps the VL53L4CX to achieve the best-ranging performance even when a Click board™ is hidden behind a wide range of cover glass materials. Specifically designed for long-range and multi-target measurements, the VL53L4CX provides accurate distance measurements up to 6m with excellent results over short distances and 18° FoV (Field

of View), improving performances under ambient light. Thanks to ST's patented algorithms, the VL53L4CX can detect multiple objects within the FoV with depth understanding. ST histogram algorithms ensure cover glass crosstalk immunity beyond 80cm and dynamic smudge compensation for targets below 80cm. Like all Time-of-Flight sensors based on ST's FlightSense technology, the VL53L4CX records an absolute distance measurement regardless of the target color and reflectance. LightRanger 10 Click communicates with MCU using the standard I2C 2-Wire interface to read data and configure settings with a maximum clock frequency of 1MHz. This Click board™ can be enabled or disabled using the EN pin of the mikroBUS™ socket, hence, offering a switch

operation to turn ON the initial boot sequence of the VL53L4CX. It also possesses an additional interrupt pin, routed to the INT pin on the mikroBUS™ socket, indicating when a ranging measurement is available. This Click board™ can only be operated from a 3.3V logic voltage level. Therefore, the board must perform appropriate logic voltage conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used as a reference for further development.

LightRanger 10 Click top side image
LightRanger 10 Click lateral side image
LightRanger 10 Click bottom side image

Features overview

Development board

UNI Clicker is a compact development board designed as a complete solution that brings the flexibility of add-on Click boards™ to your favorite microcontroller, making it a perfect starter kit for implementing your ideas. It supports a wide range of microcontrollers, such as different ARM, PIC32, dsPIC, PIC, and AVR from various vendors like Microchip, ST, NXP, and TI (regardless of their number of pins), four mikroBUS™ sockets for Click board™ connectivity, a USB connector, LED indicators, buttons, a debugger/programmer connector, and two 26-pin headers for interfacing with external electronics. Thanks to innovative manufacturing technology, it allows you to build

gadgets with unique functionalities and features quickly. Each part of the UNI Clicker development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the UNI Clicker programming method, using a third-party programmer or CODEGRIP/mikroProg connected to onboard JTAG/SWD header, the UNI Clicker board also includes a clean and regulated power supply module for the development kit. It provides two ways of board-powering; through the USB Type-C (USB-C) connector, where onboard voltage regulators provide the appropriate voltage levels to each component on the board, or using a Li-Po/Li

Ion battery via an onboard battery connector. All communication methods that mikroBUS™ itself supports are on this board (plus USB HOST/DEVICE), including the well-established mikroBUS™ socket, a standardized socket for the MCU card (SiBRAIN standard), and several user-configurable buttons and LED indicators. UNI Clicker is an integral part of the Mikroe ecosystem, allowing you to create a new application in minutes. Natively supported by Mikroe software tools, it covers many aspects of prototyping thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

UNI clicker double image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

ARM Cortex-M3

MCU Memory (KB)

256

Silicon Vendor

STMicroelectronics

Pin count

64

RAM (Bytes)

49152

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
Enable
PB9
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Interrupt
PC12
INT
NC
NC
TX
NC
NC
RX
I2C Clock
PB6
SCL
I2C Data
PB7
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

LightRanger 10 Click Schematic schematic

Step by step

Project assembly

UNI Clicker front image hardware assembly

Start by selecting your development board and Click board™. Begin with the UNI Clicker as your development board.

UNI Clicker front image hardware assembly
Thermo 28 Click front image hardware assembly
SiBRAIN for STM32F745VG front image hardware assembly
Prog-cut hardware assembly
UNI Clicker MB 1 - upright/with-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
Necto image step 7 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

After loading the code example, pressing the "DEBUG" button builds and programs it on the selected setup.

Application Output Step 1

After programming is completed, a header with buttons for various actions available in the IDE appears. By clicking the green "PLAY "button, we start reading the results achieved with Click board™.

Application Output Step 3

Upon completion of programming, the Application Output tab is automatically opened, where the achieved result can be read. In case of an inability to perform the Debug function, check if a proper connection between the MCU used by the setup and the CODEGRIP programmer has been established. A detailed explanation of the CODEGRIP-board connection can be found in the CODEGRIP User Manual. Please find it in the RESOURCES section.

Application Output Step 4

Software Support

Library Description

This library contains API for LightRanger 10 Click driver.

Key functions:

  • lightranger10_get_int_pin This function returns the INT pin logic state.

  • lightranger10_clear_interrupts This function clears the interrupts.

  • lightranger10_get_distance This function reads the target object distance in millimeters.

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 LightRanger10 Click example
 *
 * # Description
 * This example demonstrates the use of LightRanger 10 click board by reading 
 * and displaying the target object distance in millimeters.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver, performs the click default configuration, and then calibrates
 * the sensor to the object positioned at 200mm distance from the sensor.
 *
 * ## Application Task
 * Waits for the data ready interrupt, then clears the interrupt and reads the target distance
 * in millimeters and displays the results on the USB UART every 200ms approximately.
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "lightranger10.h"

static lightranger10_t lightranger10;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    lightranger10_cfg_t lightranger10_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.
    lightranger10_cfg_setup( &lightranger10_cfg );
    LIGHTRANGER10_MAP_MIKROBUS( lightranger10_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == lightranger10_init( &lightranger10, &lightranger10_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( LIGHTRANGER10_ERROR == lightranger10_default_cfg ( &lightranger10 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_printf( &logger, " --- Sensor calibration --- \r\n" );
    log_printf( &logger, " Place an object at 200mm distance from sensor in the next 5 seconds.\r\n" );
    Delay_ms( 5000 );
    log_printf( &logger, " Sensor calibration is in progress...\r\n" );
    if ( LIGHTRANGER10_ERROR == lightranger10_calibrate_distance ( &lightranger10, 200 ) )
    {
        log_error( &logger, " Sensor calibration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    while ( lightranger10_get_int_pin ( &lightranger10 ) );
    
    uint16_t distance_mm;
    if ( ( LIGHTRANGER10_OK == lightranger10_clear_interrupts ( &lightranger10 ) ) && 
         ( LIGHTRANGER10_OK == lightranger10_get_distance ( &lightranger10, &distance_mm ) ) )
    {
        log_printf ( &logger, " Distance: %u mm \r\n\n", distance_mm );
    }
}

void main ( void ) 
{
    application_init( );

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

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

Additional Support

Resources