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

//Sample using LiquidCrystal library

#include <LiquidCrystal.h>

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

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
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;
}
}

}