Provide close-range proximity sensing capabilities with VCNL4010 and PIC18F2550
Detect when something is nearby without physically touching it
Published Nov 01, 2023
Click board™
Proximity Click
Dev Board
EasyPIC v8
Compiler
NECTO Studio
MCU
PIC18F2550
Enhance safety and security by providing real-time awareness of nearby objects or individuals
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Hardware Overview
How does it work?
Proximity Click is based on the VCNL4010, a fully integrated proximity and ambient light sensor from Vishay Semiconductors. The VCNL4010 combines an infrared emitter and PIN photodiode for proximity measurement, ambient light sensor, and signal processing IC in a package with a 16-bit ADC. With a proximity range of up to 20cm (7.9") and light range from 0.25lx to 16klx, it supports conventional backlight, display brightness auto-adjustment, and proximity sensing to minimize accidental touch input in consumer and industrial
applications because no mechanical barriers are required to isolate the emitter from the detector optically. The VCNL4010 communicates with MCU using the standard I2C 2-Wire interface to read data and configure settings, compatible with all I2C modes up to 3.4MHz. The standard serial digital interface access "Proximity Signal" and "Light Intensity" without complex calculation and programming by an external controller. Besides, the programmable interrupt function, routed to the INT pin on the mikroBUS™ socket, offers wake-up
functionality for the host MCU when a proximity event or ambient light change occurs, which reduces processing overhead by eliminating the need for continuous polling. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the I/O level jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used for development.
Features overview
Development board
EasyPIC v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports many high pin count 8-bit PIC microcontrollers from Microchip, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer. 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, EasyPIC v8 provides a fluid and immersive working experience, allowing access anywhere and under any
circumstances at any time. Each part of the EasyPIC 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 DEVICE, and CAN are also included, including the well-established mikroBUS™ standard, two display options (graphical and character-based LCD), and several different DIP sockets. These sockets cover a wide range of 8-bit PIC MCUs, from the smallest PIC MCU devices with only eight up to forty pins. EasyPIC 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
Architecture
PIC
MCU Memory (KB)
32
Silicon Vendor
Microchip
Pin count
28
RAM (Bytes)
2048
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 EasyPIC v8 as your development board.
Track your results in real time
Application Output
After pressing the "FLASH" button on the left-side panel, it is necessary to open the UART terminal to display the achieved results. By clicking on the Tools icon in the right-hand panel, multiple different functions are displayed, among which is the UART Terminal. Click on the offered "UART Terminal" icon.
Once the UART terminal is opened, the window takes on a new form. At the top of the tab are two buttons, one for adjusting the parameters of the UART terminal and the other for connecting the UART terminal. The tab's lower part is reserved for displaying the achieved results. Before connecting, the terminal has a Disconnected status, indicating that the terminal is not yet active. Before connecting, it is necessary to check the set parameters of the UART terminal. Click on the "OPTIONS" button.
In the newly opened UART Terminal Options field, we check if the terminal settings are correct, such as the set port and the Baud rate of UART communication. If the data is not displayed properly, it is possible that the Baud rate value is not set correctly and needs to be adjusted to 115200. If all the parameters are set correctly, click on "CONFIGURE".
The next step is to click on the "CONNECT" button, after which the 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 Proximity Click driver.
Key functions:
proximity_write_data- Functions for write dataproximity_read_prox_data- Functions for reads Proximity dataproximity_read_ambient_light- Functions for reads Ambient light
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
* \brief Proximity Click example
*
* # Description
* Measures proximity data and ambient light.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initialization driver init and sets chip on the default mode
*
* ## Application Task
* Reads Proximity data and Ambient light data and logs data to USBUART every 500 ms.
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "proximity.h"
// ------------------------------------------------------------------ VARIABLES
static proximity_t proximity;
static log_t logger;
uint16_t proximity_ambi_value;
uint16_t proximity_proxi_value;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
proximity_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 ----" );
// Click initialization.
proximity_cfg_setup( &cfg );
PROXIMITY_MAP_MIKROBUS( cfg, MIKROBUS_1 );
proximity_init( &proximity, &cfg );
proximity_set_default_mode( &proximity );
}
void application_task ( void )
{
// Task implementation.
proximity_ambi_value = proximity_read_ambient_light( &proximity );
proximity_proxi_value = proximity_read_prox_data( &proximity );
log_printf( &logger, "Proximity: %u\r\n", proximity_proxi_value );
log_printf( &logger, " Ambient: %u LUX\r\n ", proximity_ambi_value );
Delay_ms( 500 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
