Unleash the potential of adaptive lighting control using SFH-5701 and STM32F410RB
Ambient light sensing: The key to comfort and convenience
Published Oct 08, 2024
Click board™
Ambient 7 Click
Dev Board
Nucleo 64 with STM32F410RB MCU
Compiler
NECTO Studio
MCU
STM32F410RB
From energy savings to personalized comfort, our ambient light intensity-sensing solution empowers you to take control of your lighting environment effortlessly
A
A
Hardware Overview
How does it work?
Ambient 7 Click is based on the SFH 5701 A01, an accurate light-intensity sensor from ams OSRAM. This sensor has many features that make it a perfect solution for small designs such as the Ambient 7 Click board™. One of these features is certainly its high level of integration, that allows a minimal number of external components, leaving room for an additional operational amplifier, labeled as OPA344, made by Texas Instruments, proven in many designs. As the SFH 5701 A01 limits the output current proportionaly to ambient light intensity, it creates an analog voltage on the R2 resistor (shunt). That voltage is directly proportional to the flowing current and thus the ambient light intensity. The previously mentioned operational amplifier serves as a unity gain
amplifier (buffer), to ensure good analog measurement signal integrity. The output of the unity gain amplifier is routed to the mikroBUS™ AN pin. The voltage on the AN pin can be measured by internal ADC integrated in the main MCU on the development board. The accuracy of SFH 5701 A01 sensor is not influenced by the light source type. It is calibrated so its spectral response is closely matched to a spectral response of the human eye. It is also worth to mention that the sensor qualification test plan is referenced to the guidelines of AEC-Q102 – a failure mechanism based stress test qualification for discrete optoelectronic semiconductors in automotive applications. Built in thermal compensation ensures that the measurement results are valid in
wide temperature range and thanks to integrated dark current suppression, the output signal while the sensor is exposed to dark environment is as minimal as possible. The sensor is operational in very wide Illuminance range – from 0.01lx up to 10000lx. In other words, it has linear response over 6 decades of illumination range. This Click board™ can be operated only with a 5V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. Also, it 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
Nucleo-64 with STM32F410RB 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-M4
MCU Memory (KB)
128
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
32768
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 STM32F410RB 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 Ambient 7 Click driver.
Key functions:
ambient7_read_an_pin_value- This function reads results of AD conversion of the AN pinambient7_read_an_pin_voltage- This function reads results of AD conversion of the AN pin and converts them to proportional voltage level.
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
* \brief Ambient7 Click example
*
* # Description
* Reads 12-bit ADC value.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes ADC and LOG for logging data.
*
* ## Application Task
* Reads ADC value and this data logs to USBUART every 1 sec.
*
* *note:*
* Illuminance range [ EV ] - from 0.01 [ lx ] to 10k [ lx ]
* depending on the ADC you are using.
*
* \author Luka Filipovic
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "ambient7.h"
// ------------------------------------------------------------------ VARIABLES
static ambient7_t ambient7;
static log_t logger;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
ambient7_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 ----" );
log_printf( &logger, "------------------\r\n" );
// Click initialization.
ambient7_cfg_setup( &cfg );
AMBIENT7_MAP_MIKROBUS( cfg, MIKROBUS_1 );
ambient7_init( &ambient7, &cfg );
log_printf( &logger, " Ambient 7 Click\r\n" );
log_printf( &logger, "------------------\r\n" );
Delay_ms( 100 );
}
void application_task ( void )
{
ambient7_data_t tmp;
// Task implementation.
tmp = ambient7_generic_read ( &ambient7 );
log_printf( &logger, " ADC value \r\n" );
log_printf( &logger, " [ DEC ] : %d\r\n", tmp );
log_printf( &logger, " [ HEX ] : 0x%x \r\n", tmp );
log_printf( &logger, "------------------\r\n" );
Delay_ms( 1000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
Additional Support
Resources
Category:Optical
