Intermediate
30 min
0

Optimize processes and workflows with accurate distance measurements provided by VL53L0X and PIC18LF46K42

Measure distances with high precision and reliability

LightRanger 2 Click with EasyPIC v7

Published Nov 01, 2023

Click board™

LightRanger 2 Click

Development board

EasyPIC v7

Compiler

NECTO Studio

MCU

PIC18LF46K42

Drive innovation in various fields by integrating gesture recognition and ranging capabilities

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Hardware Overview

How does it work?

LightRanger 2 Click is based on the VL53L0X, the world’s smallest Time-of-Flight (ToF) ranging and gesture detection sensor from STMicroelectronics. The VL53L0X integrates a leading-edge SPAD array (Single Photon Avalanche Diodes) and embeds ST’s second generation FlightSense™ patented technology. FlightSense™ technology measures the time it takes for a photon to reach the nearest object. The photon travel time is multiplied by the speed of light, and a distance is calculated from there. The photon travel time is not affected by reflectance, and this kind of technology is immune to ambient illumination and optical path variations. The VL53L0X’s 940nm VCSEL emitter (Vertical Cavity Surface-Emitting Laser) is invisible to the human eye, and coupled with internal physical infrared filters, it enables longer ranging distance, higher immunity to ambient light

and better robustness to cover-glass optical cross-talk. The VL53L0X has three ranging modes. The Single-ranging mode is performed only once after the function is called. The Continuous ranging mode is performed continuously, and as soon as the measurement is finished, another one is started without delay. The time-ranging mode is the same as the Continuous mode, with a user-defined delay between measurements. LightRanger 2 Click uses a standard 2-Wire I2C serial interface to communicate with the host MCU, supporting speeds up to 400kbit/s. The data can be obtained by polling the sensor over the I2C interface or by an interrupt feature when the sensor sends the interrupt over the INT pin to the host when a new measurement is available. There is an EN pin to turn the sensor ON or OFF. As this Click board™ can work on both the 3.3V and the

5V logic level devices, it features a few logic level translators. For I2C interface logic level translation, the LightRanger 2 Click uses the PCA9306, a dual bidirectional I2C bus and SMBus voltage-level translator from Texas Instruments. For additional enable and interrupt pins, this Click board™ uses a couple of SN74LVC1T45s, single-bit dual-supply bus transceivers with configurable voltage translation, and 3-state outputs from Texas Instruments. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the LOGIC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this 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.

LightRanger 2 Click top side image
LightRanger 2 Click bottom side image

Features overview

Development board

EasyPIC v7 is the seventh generation of PIC development boards specially designed to develop embedded applications rapidly. It supports a wide range of 8-bit PIC microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB-B. 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 v7 allows you to connect accessory boards, sensors, and custom electronics more efficiently than ever. Each part of

the EasyPIC v7 development board contains the components necessary for the most efficient operation of the same board. An integrated mikroProg, a fast USB 2.0 programmer with mikroICD hardware In-Circuit Debugger, offers many valuable programming/debugging options and seamless integration with the Mikroe software environment. Besides it also includes a clean and regulated power supply block 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-B (USB-B) 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 v7 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 v7 horizontal image

Microcontroller Overview

MCU Card / MCU

PIC18LF46K42

Architecture

PIC

MCU Memory (KB)

64

Silicon Vendor

Microchip

Pin count

40

RAM (Bytes)

4096

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
Enable
RE1
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
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

LightRanger 2 Click Schematic schematic

Step by step

Project assembly

EasyPIC v7 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyPIC v7 as your development board.

EasyPIC v7 front image hardware assembly
Buck 22 Click front image hardware assembly
MCU DIP 40 hardware assembly
EasyPIC v7 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 LightRanger 2 Click driver.

Key functions:

  • lightranger2_write_byte - This function writes a byte of data to the targeted 8-bit register

  • lightranger2_read_bytes - This function reads a sequential data starting from the targeted 8-bit register

  • lightranger2_get_range_continuous - This function gets a range measurement in millimeters when continuous mode is active

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 
 * \brief LightRanger2 Click example
 * 
 * # Description
 * This example collects data from the sensor, calculates it, and then logs the 
 * results.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initialization driver,
 * enable Vl6180X sensor, hardware reset and sets default configuration of
 * Vl6180X, also write log.
 * 
 * ## Application Task  
 * This is a example which demonstrates the use of LightRanger 2 Click board.
 * Measures the distance of the object from the sensor.
 * Results are being sent to the Usart Terminal where you can track their changes.
 * All data logs on usb uart for aproximetly every 1 sec when the data value changes.
 * 

 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "lightranger2.h"

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

static lightranger2_t lightranger2;
static log_t logger;

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

void application_init ( void )
{
    log_cfg_t log_cfg;
    lightranger2_cfg_t cfg;

    /** 
     * 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.

    lightranger2_cfg_setup( &cfg );
    LIGHTRANGER2_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    lightranger2_init( &lightranger2, &cfg );
    lightranger2_default_cfg( &lightranger2 );
    
    lightranger2_start_continuous( &lightranger2, 0 );
    Delay_ms( 100 );
}

void application_task ( void )
{
    uint16_t distance;
    
    distance = lightranger2_get_range_continuous( &lightranger2 );
    Delay_ms( 10 );
    
    if ( distance )
    {
        log_printf( &logger, "Distance: %u mm \r\n", distance );
        Delay_ms( 100 );
    }
}

void main ( void )
{
    application_init( );

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


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

Additional Support

Resources