Arduino LCD 1602 KeyPad Shield จอแสดงผล LCD ขนาด 16 ตัวอักษร 2 บรรทัด พร้อมปุ่มกด

//Sample using LiquidCrystal library

#include

/*******************************************************

This program will test the LCD panel and the buttons

Mark Bramwell, July 2010

********************************************************/

// select the pins used on the LCD panel

LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

// define some values used by the panel and buttons

int lcd_key     = 0;

int adc_key_in  = 0;

#define btnRIGHT  0

#define btnUP     1

#define btnDOWN   2

#define btnLEFT   3

#define btnSELECT 4

#define btnNONE   5

// read the buttons

int read_LCD_buttons()

{

 adc_key_in = analogRead(0);      // read the value from the sensor 

 // my buttons when read are centered at these valies: 0, 144, 329, 504, 741

 // we add approx 50 to those values and check to see if we are close

 if (adc_key_in > 1000) return btnNONE; // We make this the 1st option for speed reasons since it will be the most likely result

 // For V1.1 us this threshold

 if (adc_key_in < 50)   return btnRIGHT;  

 if (adc_key_in < 250)  return btnUP; 

 if (adc_key_in < 450)  return btnDOWN; 

 if (adc_key_in < 650)  return btnLEFT; 

 if (adc_key_in < 850)  return btnSELECT;  

 // For V1.0 comment the other threshold and use the one below:

/*

 if (adc_key_in < 50)   return btnRIGHT;  

 if (adc_key_in < 195)  return btnUP; 

 if (adc_key_in < 380)  return btnDOWN; 

 if (adc_key_in < 555)  return btnLEFT; 

 if (adc_key_in < 790)  return btnSELECT;   

*/

 return btnNONE;  // when all others fail, return this...

}

void setup()

{

 lcd.begin(16, 2);              // start the library

 lcd.setCursor(0,0);

 lcd.print("Push the buttons"); // print a simple message

}

void loop()

{

 lcd.setCursor(9,1);            // move cursor to second line "1" and 9 spaces over

 lcd.print(millis()/1000);      // display seconds elapsed since power-up

 lcd.setCursor(0,1);            // move to the begining of the second line

 lcd_key = read_LCD_buttons();  // read the buttons

 switch (lcd_key)               // depending on which button was pushed, we perform an action

 {

   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;

     }

 }

}