Arduino Blinker w/ LCD KeyPad Shield

LCD_Blinker.ino

#include <LiquidCrystal.h>

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

#define toggledRelay 23 // relay 1

int currentPosition = 0;
int previousButtonPressTime = 0;
int previousFlashingTime = 0;
int amount = 0;
bool relayIsOn = false;

// read the buttons
int read_LCD_buttons()
{
  int 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;

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


void setup()
{

  pinMode(toggledRelay, OUTPUT);
  pinMode(toggledRelay + 2, OUTPUT);
  pinMode(toggledRelay + 4, OUTPUT);
  digitalWrite(toggledRelay + 2, LOW);  
  digitalWrite(toggledRelay + 4, LOW);  
  lcd.begin(16, 2);              // start the library
  lcd.setCursor(0, 0);
  lcd.print("---D F T B A---"); // print a simple message
  lcd.setCursor(0, 1);
  lcd.print("0 0 0 0 0 0 0 0"); // print a simple message
  lcd.blink();
  lcd.cursor();

  Serial.begin(9600);

}

void loop()
{

  lcd.setCursor(currentPosition * 2, 1);           // move to the begining of the second line
  int lcd_key = read_LCD_buttons();  // read the buttons
  int newTime = millis();
  int delta = newTime - previousButtonPressTime;
  if (delta >= 500)
  {
    switch (lcd_key)               // depending on which button was pushed, we perform an action
    {
      case btnRIGHT:
        {
          currentPosition = (currentPosition >= 7) ? 7 : currentPosition + 1;
          previousButtonPressTime = newTime;
          break;
        }
      case btnLEFT:
        {
          currentPosition = (currentPosition <= 0) ? 0 : currentPosition - 1;
          previousButtonPressTime = newTime;
          break;
        }
      case btnSELECT:
        {
          bool isAlreadySelected = amount & (1 << currentPosition);
          int temp = (1 << currentPosition) * pow(-1 , isAlreadySelected);
          amount += temp;
          Serial.println(amount);
          lcd.print(!isAlreadySelected);
          previousButtonPressTime = newTime;
          break;
        }
      case btnNONE:
        {
          break;
        }
    }
    lcd.setCursor(currentPosition * 2, 1);
  }
  delta = newTime - previousFlashingTime;
  if(amount != 0 && delta > (1000.0 / amount)){
    previousFlashingTime = newTime;
    relayIsOn = !relayIsOn;
    digitalWrite(toggledRelay, relayIsOn ? HIGH : LOW);  
  } else if(amount == 0 && delta > (1000.0 / amount)){
    previousFlashingTime = newTime;
    relayIsOn = true;
    digitalWrite(toggledRelay, HIGH);  
  }
}