//example use of LCD4Bit_mod library

#include <LCD4Bit_mod.h> 
//create object to control an LCD.  
//number of lines in display=1
LCD4Bit_mod lcd = LCD4Bit_mod(2); 

//Key message
char msgs[5][15] = {"Right Key OK ", 
                    "Up Key OK    ", 
                    "Down Key OK  ", 
                    "Left Key OK  ", 
                    "Select Key OK" };
int  adc_key_val[5] ={1, 520, 690, 770, 820 }; // max  
int NUM_KEYS = 5;
int adc_key_in;
int old_adc = 0;
int key=-1;
int oldkey=-1;

void setup() { 
  pinMode(13, OUTPUT);  //we'll use the debug LED to output a heartbeat

  lcd.init();
  //optionally, now set up our application-specific display settings, overriding whatever the lcd did in lcd.init()
  //lcd.commandWrite(0x0F);//cursor on, display on, blink on.  (nasty!)
   lcd.clear();
  lcd.printIn("KEYPAD testing... pressing");

  Serial.begin(115200);
  Serial.println("Keypad testing over serial");
}

void loop() {

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

  if (old_adc != adc_key_in)
    Serial.println(old_adc = adc_key_in);

  digitalWrite(13, HIGH);  
  key = get_key(adc_key_in);		        // convert into key press
	
	if (key != oldkey)				    // if keypress is detected
	{
    delay(50);		// wait for debounce time
		adc_key_in = analogRead(0);    // read the value from the sensor  
    key = get_key(adc_key_in);		        // convert into key press
    if (key != oldkey)				
    {			
      oldkey = key;
      if (key >=0){
      lcd.cursorTo(2, 0);  //line=2, x=0
  			lcd.printIn(msgs[key]);
        Serial.print("adc=");
        Serial.print(adc_key_in);
        Serial.print(" key=");
        Serial.println(key);
      }
    }
  }
  
  //delay(1000);
  digitalWrite(13, LOW);
  

 
  
  
}

// Convert ADC value to key number
int get_key(unsigned int input)
{
	int k;
    
	for (k = 0; k < NUM_KEYS; k++)
	{
		if (input < adc_key_val[k])
		{
           
    return k;
        }
	}
    
    if (k >= NUM_KEYS)
        k = -1;     // No valid key pressed
    
    return k;
}