Example Code for Arduino-Set RGB Backlight Color

Hardware Preparation

• DFRduino UNO (or similar) x 1
• Gravity IO expansion Shield x1
• Gravity: I2C LCD1602 RGB Backlight Module x1
• M-M/F-M/F-F Jumper wires

Software Preparation

• Arduino IDE, Click to Download Arduino IDE from Arduino®
• Please download the LCD library: DFRobot RGB LCD. About How to install Libraries in Arduino IDE

Wiring Diagram

Other Preparation Work

Change the RGBaddr value based on the hardware version

When uploaded the codes into UNO, open serial monitor, set baud rate to 115200 and select no EOF.

Note: you have to reset the mainboard for every input. The RGB range is 0-255.

Sample Code

/*!
 * @file SetColor.ino
 * @brief Serial port input Format：255 255 255,There is no end or newline
 * @copyright	Copyright (c) 2010 DFRobot Co.Ltd (http://www.dfrobot.com)
 * @licence     The MIT License (MIT)
 * @maintainer [yangfeng]([email protected])
 * @version  V1.0
 * @date  2021-09-24
 * @url https://github.com/DFRobot/DFRobot_RGBLCD1602
 */
#include "DFRobot_RGBLCD1602.h"

char dtaUart[15];
char dtaLen = 0;

DFRobot_RGBLCD1602 lcd(/*RGBAddr*/0x2D ,/*lcdCols*/16,/*lcdRows*/2);  //16 characters and 2 lines of show

void setup() {
	Serial.begin(115200);
    /**
     *  @brief initialize the LCD and master IIC
     */ 
    lcd.init();
    // Print a message to the LCD.
    lcd.print("set color");
}

void loop() {
    if(dtaLen == 11) {
        int r = (dtaUart[0]-'0')*100 + (dtaUart[1] - '0')*10 + (dtaUart[2] - '0');          // get r
        int g = (dtaUart[4]-'0')*100 + (dtaUart[5] - '0')*10 + (dtaUart[6] - '0');
        int b = (dtaUart[8]-'0')*100 + (dtaUart[9] - '0')*10 + (dtaUart[10] - '0');
        
        dtaLen = 0;
        /**
         *  @brief set RGB
         *  @param r  red   range(0-255)
         *  @param g  green range(0-255)
         *  @param b  blue  range(0-255)
         */
        lcd.setRGB(r, g, b);

        Serial.println("get data");
        
        Serial.println(r);
        Serial.println(g);
        Serial.println(b);
        Serial.println();

    }
}

void serialEvent() {
    while(Serial.available()) {
        dtaUart[dtaLen++] = Serial.read();
    }
}

Result

The backlit color of the LCD1602 module changes according to the input value.

Additional Information

Input by a group of 4 numbers. For instance, for 12302540123, the input result will be 123，254，123.