Example Code for Arduino-Button Cascading

Hardware Preparation

• DFRduino UNO R3 (SKU: DFR0216) × 1
• Gravity: IO Expansion Shield for Arduino V7.1 (SKU: DFR0216) × 1
• Gravity: I2C RGB LED Button Module (SKU: DFR0991) × 6
• Gravity-4P I2C/UART Sensor Cable(DFR0991 is equipped with one of these lines) × 6
• USB Cable × 1

Software Preparation

• Download Arduino IDE: Click to download Arduino IDE
• Download and install the DFRobot_RGBButton-main Library
• For Arduino IDE V1.8.19 (or earlier), install the library manually: How to Add a Library ?
• For Arduino IDE V2.0.0 (or later), directly search for the "DFRobot_RGBButton-main Library" in the Library Manager and install it.

Wiring Diagram

Cascade 6 button modules, occupying only one I2C interface of the UNO mainboard.

Sample Code

6 RGB buttons show specific color on press, white on release

#include <DFRobot_RGBButton.h>
DFRobot_RGBButton RGBButton1(&Wire, /*I2CAddr*/ 0x23);   // Button 1
DFRobot_RGBButton RGBButton2(&Wire, /*I2CAddr*/ 0x24);   // Button 2
DFRobot_RGBButton RGBButton3(&Wire, /*I2CAddr*/ 0x25);   // Button 3
DFRobot_RGBButton RGBButton4(&Wire, /*I2CAddr*/ 0x26);   // Button 4
DFRobot_RGBButton RGBButton5(&Wire, /*I2CAddr*/ 0x27);   // Button 5
DFRobot_RGBButton RGBButton6(&Wire, /*I2CAddr*/ 0x28);   // Button 6

void setup(void)
{ Serial.begin(115200);
  while( ! RGBButton1.begin() ){
  Serial.println("1");
  delay(3000);}
  while( ! RGBButton2.begin() ){
    Serial.println("2");
    delay(3000);
  }
  while( ! RGBButton3.begin() ){
    Serial.println("3");
    delay(3000);
  }
  while( ! RGBButton4.begin() ){
  Serial.println("4");
  delay(3000);}
  while( ! RGBButton5.begin() ){
    Serial.println("5");
    delay(3000);
  }
  while( ! RGBButton6.begin() ){
    Serial.println("6");
    delay(3000);
  }
  Serial.println("Begin ok!\n");
  RGBButton1.setRGBColor(RGBButton1.eWhite);
  RGBButton2.setRGBColor(RGBButton2.eWhite);
  RGBButton3.setRGBColor(RGBButton3.eWhite);
  RGBButton4.setRGBColor(RGBButton4.eWhite);
  RGBButton5.setRGBColor(RGBButton5.eWhite);
  RGBButton6.setRGBColor(RGBButton6.eWhite);
}

uint8_t flag1 = 0, flag2 = 0, flag3 = 0, flag4 = 0, flag5 = 0, flag6 = 0;

void loop()
{  if( RGBButton1.getButtonStatus() ) {   // Button 1, show red LED when pressed
    flag1 = 1;
    RGBButton1.setRGBColor(RGBButton1.eRed);
    delay(50);
  } else if( 1 == flag1 ) {
    flag1 = 0;
    RGBButton1.setRGBColor(RGBButton1.eWhite);
  }

  if( RGBButton2.getButtonStatus() ) {   // Button 2, show orange LED when pressed
    flag2 = 1;
    RGBButton2.setRGBColor(RGBButton2.eOrange);
    delay(50);
  } else if( 1 == flag2 ) {
    flag2 = 0;
    RGBButton2.setRGBColor(RGBButton2.eWhite);
  }

  if( RGBButton3.getButtonStatus() ) {   // Button 3, show yellow LED when pressed
    flag3 = 1;
    RGBButton3.setRGBColor(RGBButton3.eYellow);
    delay(50);
  } else if( 1 == flag3 ) {
    flag3 = 0;
    RGBButton3.setRGBColor(RGBButton3.eWhite);
  }
   if( RGBButton4.getButtonStatus() ) {   // Button 4, show green LED when pressed
    flag4 = 1;
    RGBButton4.setRGBColor(RGBButton4.eGreen);
    delay(50);
  } else if( 1 == flag4 ) {
    flag4 = 0;
    RGBButton4.setRGBColor(RGBButton4.eWhite);
  }

  if( RGBButton5.getButtonStatus() ) {   // Button 5, show blue LED when pressed
    flag5 = 1;
    RGBButton5.setRGBColor(RGBButton5.eBlue);
    delay(50);
  } else if( 1 == flag5 ) {
    flag5 = 0;
    RGBButton5.setRGBColor(RGBButton5.eWhite);
  }

  if( RGBButton6.getButtonStatus() ) {   // Button 6, show purple LED when pressed
    flag6 = 1;
    RGBButton6.setRGBColor(RGBButton6.ePurple);
    delay(50);
  } else if( 1 == flag6 ) {
    flag6 = 0;
    RGBButton6.setRGBColor(RGBButton6.eWhite);
  }
}

Result

6 button modules are cascaded, they all show white color by default. When a button is pressed, its corresponding RGB LED shows the color set in the program. For example, press the first button, and its button light turns red.