Perform accurate distance measurements using VL53L4CX and TM4C129ENCPDT
Keep your target in sight
Published Mar 09, 2023
Click board™
LightRanger 10 Click
Dev. board
Fusion for Tiva v8
Compiler
NECTO Studio
MCU
TM4C129ENCPDT
Detect the distance of an object, regardless of its color and reflectance
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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.
Features overview
Development board
Fusion for TIVA v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of microcontrollers, such as different 32-bit ARM® Cortex®-M based MCUs from Texas Instruments, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over a WiFi network. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, Fusion for TIVA v8 provides a fluid and immersive working experience, allowing access
anywhere and under any circumstances at any time. Each part of the Fusion for TIVA v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector.
Communication options such as USB-UART, USB HOST/DEVICE, CAN (on the MCU card, if supported), and Ethernet is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. Fusion for TIVA v8 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.
Microcontroller Overview
MCU Card / MCU
Type
8th Generation
Architecture
ARM Cortex-M4
MCU Memory (KB)
1024
Silicon Vendor
Texas Instruments
Pin count
128
RAM (Bytes)
262144
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Click board™ Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Fusion for Tiva v8 as your development board.
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 LightRanger 10 Click driver.
Key functions:
lightranger10_get_int_pinThis function returns the INT pin logic state.lightranger10_clear_interruptsThis function clears the interrupts.lightranger10_get_distanceThis function reads the target object distance in millimeters.
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 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
