Example Code for Arduino-Button Control

Hardware Preparation

• Arduino UNO x1
• LCD Keypad Shield V2.0 x1
• M-M/F-M/F-F Jumper wires

Software Preparation

• Arduino IDE Click to Download Arduino IDE

Wiring Diagram

Other Preparation Work

If your Arduino IDE does not have this library, please follow the steps below to install it.

• Click the link to download library and reference files.

• Unzip this folder and copy it to the libraries folder under Arduino installation directory.

About how to install the library?

• Next, open the Arduino IDE and copy the following code to the IDE window. (Delete all contents in the IDE just opened!)
• Select the correct serial port and board (Arduino UNO).

Sample Code

/*!
 * @file Button.ino
 * @brief Button.
 * @copyright	Copyright (c) 2010 DFRobot Co.Ltd (http://www.dfrobot.com)
 * @licence     The MIT License (MIT)
 * @maintainer DFRobot
 * @version  V1.0
 * @date  2023-07-03
 * @url https://github.com/DFRobot/DFRobot_RGBLCD1602
 */
#include "DFRobot_RGBLCD1602.h"

/*
Change the RGBaddr value based on the hardware version
-----------------------------------------
       Moudule        | Version| RGBAddr|
-----------------------------------------
  LCD1602 Module      |  V1.0  | 0x60   |
-----------------------------------------
  LCD1602 Module      |  V1.1  | 0x6B   |
-----------------------------------------
  LCD1602 RGB Module  |  V1.0  | 0x60   |
-----------------------------------------
  LCD1602 RGB Module  |  V2.0  | 0x2D   |
-----------------------------------------
*/
DFRobot_RGBLCD1602 lcd(/*RGBAddr*/0x60 ,/*lcdCols*/16,/*lcdRows*/2);  //16 characters and 2 lines of show

// Define keys
int lcdKey     = 0;
int adcKeyIN  = 0;
int r=255;   //Set red brightness (Range: 0-255) 
int g=255;   //Set green brightness 
int b=0;     //Set blue brightness

#define btnRIGHT  0
#define btnUP     1
#define btnDOWN   2
#define btnLEFT   3
#define btnSELECT 4
#define btnNONE   5

void setup()
{
  Serial.begin(9600);
  lcd.init();
  lcd.setRGB(r,g,b);  // Set RGB
}

int readLcdButtons()    // Determine which button is pressed
{
 adcKeyIN = analogRead(0);          // 0 read the ADC from analog values
 // By setting different threshold, you can read the corresponding to the appropriate buttons
 if (adcKeyIN > 1000) return btnNONE;
 if (adcKeyIN < 50)   return btnRIGHT;
 if (adcKeyIN < 250)  return btnUP;
 if (adcKeyIN < 450)  return btnDOWN;
 if (adcKeyIN < 650)  return btnLEFT;
 if (adcKeyIN < 850)  return btnSELECT;
 return btnNONE;
}

void loop()
{
 lcd.setCursor(9,1);            //Set display output position 
 lcd.print(millis()/1000);      //Output time(second) 
 lcd.setRGB(r,g,b);             //Set RGB
 lcd.setCursor(0,1);            
 lcdKey = readLcdButtons();     // Read button content
 switch (lcdKey)                // Select to output content according to the pressed button
 {
   case btnRIGHT:
     {
     lcd.print("RIGHT ");
     break;
     }
   case btnLEFT:
     {
     lcd.print("LEFT   ");
     break;
     }
   case btnUP:
     {
     lcd.print("UP    ");
     break;
     }
   case btnDOWN:
     {
     lcd.print("DOWN  ");
     break;
     }
   case btnSELECT:
     {
     lcd.print("SELECT");
     break;
     }
     case btnNONE:
     {
     lcd.print("NONE  ");
     break;
     }
 }          
}

Result

Yellow background, output NONE when no button pressed, otherwise, output the corresponding button.