Intermediate
30 min

Provide accurate information on ambient light intensity with BU27030NUC and PIC32MX675F512L

Shine bright, shine right: Ambient light intelligence!

Ambient 20 Click with UNI Clicker

Published Sep 19, 2023

Click board™

Ambient 20 Click

Dev Board

UNI Clicker

Compiler

NECTO Studio

MCU

PIC32MX675F512L

Improve the overall quality of life in residential and commercial spaces by ensuring that lighting aligns with natural daylight patterns

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Hardware Overview

How does it work?

Ambient 20 Click is based on the BU27030NUC, a high-sensitivity light-to-digital converter from Rohm Semiconductor that transforms light intensity into a digital output signal. The BU27030NUC provides ambient light sensing (ALS) that approximates the human eye response to light intensity under various lighting conditions and through different attenuation materials. It has a flexible and wide operating range of up to 20klx with a maximum resolution of 0.0007lux/count, even when mounted behind dark glass. The BU27030NUC also features inherent 50Hz/60Hz

light noise rejection and excellent IR-cut characteristics, making this board most suitable for brightness control functions, helping to reduce power consumption. Ambient 20 Click communicates with an MCU using the standard I2C 2-Wire interface to read data and configure settings, supporting Standard Mode operation with a clock frequency of 100kHz and Fast Mode up to 400kHz. Despite its simple design, the BU27030NUC provides users with two outputs with different spectral responses. Thanks to the simplicity of the I2C interface, users can access not

only the data of both outputs but also other configuration parameters such as the measurement mode of the desired output, gain settings, data update status, and the activation of the measurement process itself. This Click board™ can be operated only with a 3.3V 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.

Ambient 20 Click top side image
Ambient 20 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

PIC32

MCU Memory (KB)

512

Silicon Vendor

Microchip

Pin count

100

RAM (Bytes)

65536

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
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
NC
NC
INT
NC
NC
TX
NC
NC
RX
I2C Clock
PA2
SCL
I2C Data
PA3
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

Ambient 20 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 Ambient 20 Click driver.

Key functions:

  • ambient20_sw_reset - Software reset function

  • ambient20_set_gain - Set data gain function

  • ambient20_read_data0 - Read data0 function.

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 Ambient 20 Click example
 *
 * # Description
 * This example demonstrates the use of Ambient 20 click board by measuring 
 * the ambient light level.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and performs the click default configuration.
 *
 * ## Application Task
 * Measuring ambient light level by reading DATA0 and DATA1 channels of the Ambient 20 click board
 * and displaying it using UART Serial terminal.
 *
 * @author Stefan Ilic
 *
 */

#include "board.h"
#include "log.h"
#include "ambient20.h"

static ambient20_t ambient20;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    ambient20_cfg_t ambient20_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.
    ambient20_cfg_setup( &ambient20_cfg );
    AMBIENT20_MAP_MIKROBUS( ambient20_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == ambient20_init( &ambient20, &ambient20_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( AMBIENT20_ERROR == ambient20_default_cfg ( &ambient20 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    uint8_t id;
    ambient20_get_manufacturer_id( &ambient20, &id );
    
    log_printf( &logger, "- - - - - - - - - - - - -\r\n" );
    log_printf( &logger, " Part ID = 0x%.2X \r\n", ( uint16_t ) id );
    log_printf( &logger, "- - - - - - - - - - - - -\r\n" );

    
    log_info( &logger, " Application Task " );
    log_printf( &logger, "- - - - - - - - - - - - -\r\n" );
}

void application_task ( void ) 
{
    //  Task implementation.
    float data0, data1;
    ambient20_get_data_lux( &ambient20, &data0, &data1 );
    
    log_printf( &logger, "Data 0: %.2f lx \r\n", data0 );
    log_printf( &logger, "Data 1: %.2f lx \r\n", data1 );
    log_printf( &logger, "- - - - - - - - - - - - -\r\n" );
    
    Delay_ms( 1000 );
}

void main ( void ) 
{
    application_init( );

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

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

Additional Support

Resources