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Accurately capture and analyze colors with TCS3771 and STM32L4A6RG for a multitude of applications

Colors in the spotlight

Color 3 Click with Fusion for STM32 v8

Published Sep 19, 2023

Click board™

Color 3 Click

Development board

Fusion for STM32 v8

Compiler

NECTO Studio

MCU

STM32L4A6RG

Learn how this cutting-edge RGB color sensing technology can elevate your projects and products by ensuring true-to-life color reproduction and enhanced visual experiences

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Hardware Overview

How does it work?

Color 3 Click is based on TCS3771, a color light-to-light digital convertor with proximity sensing from ams AG, providing fast and accurate spectral measurements. The TCS3771 contains a 4×4 photodiode array comprising red-/green-/blue-filtered and clear photodiodes (four of each type), internal amplifiers, ADCs, accumulators, clocks, buffers, comparators, a state machine, and a serial interface. Four integrated ADCs convert the amplified photodiode currents simultaneously to a digital value, providing up to 16 bits of resolution, transferring the result to the data registers, and maintaining data integrity. The TCS3771 has a high sensitivity making this board suitable for operation behind dark glass. Proximity sensing uses an external light source, the SFH4441, an onboard IR

LED from ams AG, to emit light towards the reflective surface, after which the TCS3771 measures the amount of reflected light from an object which is in the light path. A TCS3771‘s internal LED driver provides a software-configurable constant current sink of 12.5mA, 25mA, 50mA, or 100mA of current, alongside programmable proximity LED pulses from 1 to 255. The amount of light detected from a reflective surface is then used to determine an object’s proximity to the sensor. This Click board™ communicates with MCU using the standard I2C 2-Wire interface to read data and configure settings, supporting a Fast Mode operation up to 400kHz. Besides, it also possesses an interrupt feature, routed to the INT pin of the mikroBUS™

socket, which serves as an alarm or monitoring function to determine whether the color light or proximity values exceed the upper threshold or go below the lower threshold. The user can also configure the persistency of the interrupt pin, which reduces the possibility of false triggers, such as noise or sudden spikes in color light conditions. 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.

Color 3 Click top side image
Color 3 Click bottom side image

Features overview

Development board

Fusion for STM32 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 32-bit ARM® Cortex®-M based MCUs from STMicroelectronics, 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 STM32 v8 provides a fluid and immersive working experience, allowing

access anywhere and under any circumstances at any time. Each part of the Fusion for STM32 v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it 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 is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. Fusion for STM32 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.

Fusion for STM32 v8 horizontal image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

ARM Cortex-M4

MCU Memory (KB)

1024

Silicon Vendor

STMicroelectronics

Pin count

64

RAM (Bytes)

327680

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
Interrupt
PB3
INT
NC
NC
TX
NC
NC
RX
I2C Clock
PB6
SCL
I2C Data
PB7
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

Color 3 Click Schematic schematic

Step by step

Project assembly

Fusion for PIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Fusion for STM32 v8 as your development board.

Fusion for PIC v8 front image hardware assembly
Buck 22 Click front image hardware assembly
SiBRAIN for PIC32MZ1024EFK144 front image hardware assembly
v8 SiBRAIN MB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
NECTO Compiler Selection Step Image hardware assembly
NECTO Output Selection Step Image hardware assembly
Necto image step 6 hardware assembly
Necto image step 7 hardware assembly
Necto image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto PreFlash Image hardware assembly

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.

UART Application Output Step 1

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.

UART Application Output Step 2

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".

UART Application Output Step 3

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.

UART Application Output Step 4

Software Support

Library Description

This library contains API for Color 3 Click driver.

Key functions:

  • color3_get_rgbc_data - This function reads data from 4 channels (Red, Green, Blue, Clear)

  • color3_rgbc_to_hsl - This function converts RGBC (red, green, blue, clear) to HSL (hue, saturation, lightness) color value

  • color3_get_color - This function returns the color name flag from the input HSL color.

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 Color3 Click example
 * 
 * # Description
 * This application return the color of object.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initalizes I2C driver, applies default settings and makes an initial log.
 * 
 * ## Application Task  
 * Checks which color is detected by the sensor.
 * The detected color name is being logged on the USBUART.
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "color3.h"

// ------------------------------------------------------------------ VARIABLES

static color3_t color3;
static log_t logger;
static uint8_t is_color;
static float color_value;

void application_init ( void )
{
    log_cfg_t log_cfg;
    color3_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.

    color3_cfg_setup( &cfg );
    COLOR3_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    color3_init( &color3, &cfg );
    Delay_ms( 100 );

    color3_set_default_settings( &color3 );
    Delay_ms( 1000 );

    log_printf( &logger, "-----------------\r\n" );
    log_printf( &logger, " Color 3  Click  \r\n" );
    log_printf( &logger, "-----------------\r\n" );
}

void application_task ( void )
{
    color_value = color3_get_color_value( &color3 );
    is_color = color3_get_color( color_value );

    switch( is_color )
    {
        case COLOR3_ORANGE_COLOR_FLAG:
        {
            log_printf( &logger, "--- Color: ORANGE\r\n" );
            break;
        }
        case COLOR3_RED_COLOR_FLAG:
        {
            log_printf( &logger, "--- Color: RED\r\n" );
            break;
        }
        case COLOR3_PINK_COLOR_FLAG:
        {
            log_printf( &logger, "--- Color: PINK\r\n" );
            break;
        }
        case COLOR3_PURPLE_COLOR_FLAG:
        {
            log_printf( &logger, "--- Color: PURPLE\r\n" );
            break;
        }
        case COLOR3_BLUE_COLOR_FLAG:
        {
            log_printf( &logger, "--- Color: BLUE\r\n" );
            break;
        }
        case COLOR3_CYAN_COLOR_FLAG:
        {
            log_printf( &logger, "--- Color: CYAN\r\n" );
            break;
        }
        case COLOR3_GREEN_COLOR_FLAG:
        {
            log_printf( &logger, "--- Color: GREEN\r\n" );
            break;
        }
        case COLOR3_YELLOW_COLOR_FLAG:
        {
            log_printf( &logger, "--- Color: YELLOW\r\n" );
            break;
        }
        default:
        {
            break;
        }
    }

    Delay_ms( 300 );
}

void main ( void )
{
    application_init( );

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


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

Additional Support

Resources