Lab 5 - Etch-a-sketch

#include <nokia_5110_lcd.h>

#define MODE_SWITCH 5
#define BLINK_BUTTON 6
#define CLEAR_BUTTON 7

#define XPIN A0
#define YPIN A1
const double XCON = .082;
const double YCON = .046;

#define WIDTH 83
#define HEIGHT 47

volatile int mode = PIXEL_ON;
volatile boolean blinkFlag = false;

//LCD PINS
#define LCD_PWR   10
#define LCD_SCE   9
#define LCD_RESET 8
#define LCD_DC    4

Nokia_5110_lcd lcd(LCD_PWR, LCD_DC, LCD_SCE, LCD_RESET);

void setup()
{
  Serial.begin (9600);
  Serial.println("Start");
  lcd.init(100); //parameter is contrast value, between 0 [low] and 127 [high]
  lcd.clear();
  pinMode(MODE_SWITCH, INPUT_PULLUP);
  pinMode(BLINK_BUTTON, INPUT_PULLUP);
  pinMode(CLEAR_BUTTON, INPUT_PULLUP);
  attachInterrupt(0, toggleMode, CHANGE);
  attachInterrupt(1, flagBlink, CHANGE);
  attachInterrupt(2, clear, CHANGE);
  toggleMode();
}

/* loop */
void loop(){
 int x = analogRead(XPIN)*XCON;
 int y = analogRead(YPIN)*YCON;
 //Serial.println("X: " + (String)x);
 //Serial.println("Y: " + (String)y);

 if(blinkFlag){
  blinkCursor(x,y);
 }
 lcd.setPixel(x, y, mode);
}

void toggleMode() {
  Serial.println(digitalRead(MODE_SWITCH));
  if(digitalRead(MODE_SWITCH) == LOW){
   mode = PIXEL_ON;
  }
  else {
   mode = PIXEL_OFF;
  }
}

void blinkCursor(int x, int y){
  Serial.println("BLINKING");
  for(int i = 0; i < 8; i++){
   if(i % 2 == 0){
     lcd.setPixel(x, y, PIXEL_ON);
   }
   else {
     lcd.setPixel(x, y, PIXEL_OFF);
   }
   delay(250);
  }
  lcd.setPixel(x, y, mode);
  blinkFlag = false;
}

void flagBlink(){
  if(digitalRead(BLINK_BUTTON) == LOW){
    Serial.println("flagBlink()");
   blinkFlag = true;
  }
}

void clear(){
 if(digitalRead(CLEAR_BUTTON) == LOW){
   lcd.clear();
 }
}