Set a new standard for accurate and reliable real-time distance insights using AFBR-S50 and STM32L073RZ
ToF technology that paves the way for precise distance metrics
Published Feb 26, 2024
Click board™
LightRanger 7 Click
Dev. board
Nucleo-64 with STM32L073RZ MCU
Compiler
NECTO Studio
MCU
STM32L073RZ
Designed with a dedication to excellence, this ToF distance measurement solution aims to be the cornerstone of innovation in fields where precision matters most, setting a new benchmark for reliable and instantaneous distance metrics
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Hardware Overview
How does it work?
LightRanger 7 Click is based on the AFBR-S50, a multi-pixel optical distance and motion measurement sensor module based on the Time-of-Flight principle from Broadcom. The AFBR-S50 is developed with a particular focus on applications with the need for the highest speed and accuracy at medium distance ranges with low power consumption. Due to its best-in-class ambient light suppression, use in outside environments is possible in direct sunlight and on white, black, colored, metallic, and retroreflective surfaces. This feature makes it suitable for optical distance measurements requiring precise 3D information and extended range like drones or AMR/AGV. This board represents an integrated solution consisting of a 32-bit MCU, RA4M2 group of Renesas MCU with Arm® Cortex®-M33 core, and a ToF sensor with an integrated infrared laser light source mounted on a compact-sized PCB. In addition to an SPI-compatible interface for data transferring to the RA4M2 MCU, the AFBR-S50 also has an interrupt
line through which the MCU can register the data-ready event. Also, such conditions and other interrupts can be visually represented using the yellow LED indicator marked with STATUS. The RA4M2 interfaces with a host MCU through UART communication via commonly used RX and TX mikorBUS™ pins. Since the AFBR-S50 is known to be used in both robotics and drones, it is essential to note that this ToF sensor is compatible with Pixhawk®, a popular general-purpose flight controller, accessible via two 4-pin CAN connectors, J1 and J2, and controllable through onboard CAN controller, the MCP2542WFD from Microchip. Also, there is a clear visual indication of the execution of the communication itself; more precisely, the user can catch the operation of CAN communication/signal transfer via orange LED indicators provided for indication of received and transmitted CAN signals. In addition, this board also offers complete debugging and programming capabilities supported through an additional header
marked with J3. With this header, the user can use a Serial Wire Debug interface for programming and debugging, available through the SWD interface pins. Besides, it also has a Micro B USB connector, allowing the board to be powered and configured by a personal computer (PC). This way, it is possible to flash the AFBR-S50 ToF sensor via bootloader. This Click board™ uses both mikroBUS™ power rails, 3.3V and 5V. 5V is necessary to power the ToF sensor, while all unnecessary communication and data transfer is done using 3.3V logic. Thanks to the onboard LDO regulator, the SPX3819, even in the standalone CAN configuration, both voltages are provided: 5V through the CAN connector, while the regulator creates a voltage of 3.3V essential for the proper operation of the MCU. 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.
Features overview
Development board
Nucleo-64 with STM32L073RZ 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.
Microcontroller Overview
MCU Card / MCU
Architecture
ARM Cortex-M0
MCU Memory (KB)
192
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
20480
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.
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 Nucleo-64 with STM32L073RZ MCU 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 7 Click driver.
Key functions:
lightranger7_reset_device- This function resets the device by toggling the rst pin state.lightranger7_generic_write- This function writes a desired number of data bytes by using UART serial interface.lightranger7_generic_read- This function reads a desired number of data bytes by using UART serial interface.
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 LightRanger 7 Click Example.
*
* # Description
* This example demonstrates the use of LightRanger 7 Click board by processing
* the incoming data and displaying them on the USB UART.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver and performs the Click default configuration.
*
* ## Application Task
* Reads and processes all incoming data and displays them on the USB UART.
*
* @note
* By default, the Click board is programmed with the AFBR_S50_Example_RA4M2 firmware.
* At the beginning this FW returns API version, chip ID, and module version. After that
* it starts the measurements and prints the recent measurement results that consists of:
* 1. Time stamp in seconds since the last MCU reset.
* 2. Range in mm (converting the Q9.22 value to mm).
* 3. Amplitude in LSB (converting the UQ12.4 value to LSB).
* 4. Signal Quality in % (100% = good signal).
* 5. Status (0: OK; < 0: Error; > 0: Warning.
* For more information refer to the AFBR-S50 GitHub repository:
* https://github.com/Broadcom/AFBR-S50-API
*
* ## Additional Function
* - static void lightranger7_clear_app_buf ( void )
* - static err_t lightranger7_process ( lightranger7_t *ctx )
*
* @author Stefan Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "lightranger7.h"
#define PROCESS_BUFFER_SIZE 200
static lightranger7_t lightranger7;
static log_t logger;
static uint8_t app_buf[ PROCESS_BUFFER_SIZE ] = { 0 };
static int32_t app_buf_len = 0;
/**
* @brief LightRanger 7 clearing application buffer.
* @details This function clears memory of application buffer and reset its length.
* @note None.
*/
static void lightranger7_clear_app_buf ( void );
/**
* @brief LightRanger 7 data reading function.
* @details This function reads data from device and concatenates data to application buffer.
* @param[in] ctx : Click context object.
* See #lightranger7_t object definition for detailed explanation.
* @return @li @c 0 - Read some data.
* @li @c -1 - Nothing is read.
* See #err_t definition for detailed explanation.
* @note None.
*/
static err_t lightranger7_process ( lightranger7_t *ctx );
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
lightranger7_cfg_t lightranger7_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.
lightranger7_cfg_setup( &lightranger7_cfg );
LIGHTRANGER7_MAP_MIKROBUS( lightranger7_cfg, MIKROBUS_1 );
if ( UART_ERROR == lightranger7_init( &lightranger7, &lightranger7_cfg ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
log_printf( &logger, " Reset device\r\n" );
lightranger7_reset_device ( &lightranger7 );
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
lightranger7_process( &lightranger7 );
if ( app_buf_len > 0 )
{
log_printf( &logger, "%s", app_buf );
lightranger7_clear_app_buf( );
}
}
int main ( void )
{
/* Do not remove this line or clock might not be set correctly. */
#ifdef PREINIT_SUPPORTED
preinit();
#endif
application_init( );
for ( ; ; )
{
application_task( );
}
return 0;
}
static void lightranger7_clear_app_buf ( void )
{
memset( app_buf, 0, app_buf_len );
app_buf_len = 0;
}
static err_t lightranger7_process ( lightranger7_t *ctx )
{
uint8_t rx_buf[ PROCESS_BUFFER_SIZE ] = { 0 };
int32_t rx_size = 0;
rx_size = lightranger7_generic_read( ctx, rx_buf, PROCESS_BUFFER_SIZE );
if ( rx_size > 0 )
{
int32_t buf_cnt = app_buf_len;
if ( ( ( app_buf_len + rx_size ) > PROCESS_BUFFER_SIZE ) && ( app_buf_len > 0 ) )
{
buf_cnt = PROCESS_BUFFER_SIZE - ( ( app_buf_len + rx_size ) - PROCESS_BUFFER_SIZE );
memmove ( app_buf, &app_buf[ PROCESS_BUFFER_SIZE - buf_cnt ], buf_cnt );
}
for ( int32_t rx_cnt = 0; rx_cnt < rx_size; rx_cnt++ )
{
if ( rx_buf[ rx_cnt ] )
{
app_buf[ buf_cnt++ ] = rx_buf[ rx_cnt ];
if ( app_buf_len < PROCESS_BUFFER_SIZE )
{
app_buf_len++;
}
}
}
return LIGHTRANGER7_OK;
}
return LIGHTRANGER7_ERROR;
}
// ------------------------------------------------------------------------ END
Additional Support
Resources
Category:Optical
