Simplify lighting management with APDS-9006-020 combined with PIC18F87J11
Whispers of illuminance
Published Sep 24, 2023
Click board™
Ambient 10 Click
Dev Board
Fusion for PIC v8
Compiler
NECTO Studio
MCU
PIC18F87J11
Join the future of smart technology with our ambient light sensing solution, designed to make life more comfortable and efficient
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Hardware Overview
How does it work?
Ambient 10 Click is based on the APDS-9006-020, an analog-output ambient light photo sensor from Broadcom Limited. It consists of a photosensor whose spectral response is close to the CIE standard photopic observer. Hence, it provides an excellent responsivity close to the human eyes' response. It has stable performance over a wide temperature and voltage range. It is characterized by good output linearity across a wide illumination range and low sensitivity variation across various light sources suitable to sense the amount of the present ambient light. The analog output signal of the APDS-9006-020 can be converted to a digital
value using MCP3221, a successive approximation A/D converter with a 12-bit resolution from Microchip using a 2-wire I2C compatible interface, or can be sent directly to an analog pin of the mikroBUS™ socket labeled as AN. Selection can be performed by onboard SMD jumper labeled as A/D SEL to an appropriate position marked as AN and ADC. The MCP3221 provides one single-ended input with low power consumption, a low maximum conversion current, and a Standby current of 250μA and 1μA, respectively. Data can be transferred at up to 100kbit/s in the Standard and 400kbit/s in the Fast Mode. Also, maximum
sample rates of 22.3kSPS with the MCP3221 are possible in a Continuous-Conversion Mode with a clock rate of 400kHz. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC 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.
Features overview
Development board
Fusion for PIC 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 PIC, dsPIC, PIC24, and PIC32 MCUs regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over WiFi. 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 PIC v8 provides a fluid and immersive working experience, allowing access anywhere and under any
circumstances at any time. Each part of the Fusion for PIC v8 development board contains the components necessary for the most efficient operation of the same board. In addition to the advanced integrated CODEGRIP programmer/debugger module, which offers many valuable programming/debugging options and seamless integration with the Mikroe software environment, the board 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 are also included, including the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options (graphical and character-based LCD). Fusion for PIC 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
PIC
MCU Memory (KB)
128
Silicon Vendor
Microchip
Pin count
80
RAM (Bytes)
3904
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Fusion for PIC v8 as your development board.
Track your results in real time
Application Output via UART Mode
1. Once the code example is loaded, pressing the "FLASH" button initiates the build process, and programs it on the created setup.
2. After the programming is completed, click on the Tools icon in the upper-right panel, and select the UART Terminal.
3. After opening the UART Terminal tab, first check the baud rate setting in the Options menu (default is 115200). If this parameter is correct, activate the terminal by clicking the "CONNECT" button.
4. Now terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.
Software Support
Library Description
This library contains API for Ambient 10 Click driver.
Key functions:
ambient10_set_vref- This function sets the voltage reference for Ambient 10 Click driverambient10_read_adc_voltage- This function reads raw 12-bit ADC data and converts it to voltage by using I2C serial interfaceambient10_voltage_to_lux- This function calculates illuminance (lux) based on the voltage input.
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 10 Click Example.
*
* # Description
* This example demonstrates the use of Ambient 10 click board.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver and sets the voltage reference.
*
* ## Application Task
* Reads the ADC voltage and then calculates the illuminance from it.
* The calculated value of illuminance in lux is being displayed on the USB UART approximately once per second.
*
* @author Stefan Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "ambient10.h"
static ambient10_t ambient10; /**< Ambient 10 Click driver object. */
static log_t logger; /**< Logger object. */
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
ambient10_cfg_t ambient10_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 );
Delay_ms( 100 );
log_info( &logger, " Application Init " );
// Click initialization.
ambient10_cfg_setup( &ambient10_cfg );
AMBIENT10_MAP_MIKROBUS( ambient10_cfg, MIKROBUS_1 );
if ( ADC_ERROR == ambient10_init( &ambient10, &ambient10_cfg ) )
{
log_error( &logger, " Application Init Error. " );
log_info( &logger, " Please, run program again... " );
for ( ; ; );
}
ambient10_set_vref( &ambient10, AMBIENT10_VREF_3V3 );
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
float voltage = 0;
if ( AMBIENT10_OK == ambient10_read_an_pin_voltage ( &ambient10, &voltage ) )
{
log_printf( &logger, " Illuminance : %u Lux\r\n\n", ambient10_voltage_to_lux( &ambient10, voltage ) );
}
Delay_ms( 1000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
