#include <avr/sleep.h>
#include <avr/wdt.h>
#ifndef cbi
#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
#endif
#ifndef sbi
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))
#endif
 
int led = 1;           // the PWM pin the LED is attached to
volatile boolean f_wdt = 1;
int counter = 0;
 
// the setup routine runs once when you press reset:
void setup() {
  pinMode(led, OUTPUT);
  setup_watchdog(15); // approximately 4 seconds sleep
 
}
 
void fade(){
  for (int i = 0; i < 255; i++){ 
    analogWrite(led, i); 
    delay(5); 
  }
  for (int i = 255; i > 0; i--){ 
    analogWrite(led, i);
    delay(5);
  }
}
 
void jumpFade(){
  for(int i = 0; i < 6; i++){
    int j = i * 50;
    analogWrite(led, j);
    delay(500);
  }
  for(int i = 5; i > 0; i--){
    int j = i * 50;
    analogWrite(led, j);
    delay(500);
  }
}
 
void morse(){
  lS();
  lA();
  lY();
  space();
  lH();
  lI();
  space();
}
 
void loop() {
  if (f_wdt==1) {  // wait for timed out watchdog / flag is set when a watchdog timeout occurs
    f_wdt=0;       // reset flag
  } 
  
  fade();
  fade();
  fade();
  system_sleep();
  
  jumpFade();
  jumpFade();
  jumpFade();
  system_sleep();
  
  morse();
  morse();
  morse();
  system_sleep();
}
 
//functions for the letters and the numbers
void lA () {dot();dash();shortspace();}//letter A in morse code!
void lB () {dash();dot();dot();dot();shortspace();}//same for B
void lC () {dash();dot();dash();dot();shortspace();}
void lD () {dash();dot();dot();shortspace();}
void lE () {dot();shortspace();}
void lF () {dot();dot();dash();dot();shortspace();}
void lG () {dash();dash();dot();shortspace();}
void lH () {dot();dot();dot();dot();shortspace();}
void lI () {dot();dot();shortspace();}
void lJ () {dot();dash();dash();dash();shortspace();}
void lK () {dash();dot();dash();shortspace();}
void lL () {dot();dash();dot();dot();shortspace();}
void lM () {dash();dash();shortspace();}
void lN () {dash();dot();shortspace();}
void lO () {dash();dash();dash();shortspace();}
void lP () {dot();dash();dash();dot();shortspace();}
void lQ () {dash();dash();dot();dash();shortspace();}
void lR () {dot();dash();dot();shortspace();}
void lS () {dot();dot();dot();shortspace();}
void lT () {dash();shortspace();}
void lU () {dot();dot();dash();shortspace();}
void lV () {dot();dot();dot();dash();shortspace();}
void lW () {dot();dash();dash();shortspace();}
void lX () {dash();dot();dot();dash();shortspace();}
void lY () {dash();dot();dash();dash();shortspace();}
void lZ () {dash();dash();dot();dot();shortspace();}
void n1 () {dot();dash();dash();dash();dash();shortspace();}//number 1 in morse code
void n2 () {dot();dot();dash();dash();dash();shortspace();}
void n3 () {dot();dot();dot();dash();dash();shortspace();}
void n4 () {dot();dot();dot();dot();dash();shortspace();}
void n5 () {dot();dot();dot();dot();dot();shortspace();}
void n6 () {dash();dot();dot();dot();dot();shortspace();}
void n7 () {dash();dash();dot();dot();dot();shortspace();}
void n8 () {dash();dash();dash();dot();dot();shortspace();}
void n9 () {dash();dash();dash();dash();dot();shortspace();}
void n0 () {dash();dash();dash();dash();dash();shortspace();}
void space () {delay (1200);}//space between words
void dot () {analogWrite(led, 150); delay (300); digitalWrite(led,LOW); delay (300);}//the dot this code make the led on for 300 than off for 300
void dash () {analogWrite(led, 150); delay (900); digitalWrite(led,LOW); delay (300);}//the dash this code make the led on for 900 than off for 300
void shortspace () {delay(600);}//space between letters
 
// set system into the sleep state 
// system wakes up when wtchdog is timed out
void system_sleep() {
  digitalWrite(led,LOW);
  cbi(ADCSRA,ADEN);                    // switch Analog to Digitalconverter OFF
  set_sleep_mode(SLEEP_MODE_PWR_DOWN); // sleep mode is set here
  sleep_enable();
  sleep_mode();                        // System sleeps here
  sleep_disable();                     // System continues execution here when watchdog timed out 
  sbi(ADCSRA,ADEN);                    // switch Analog to Digitalconverter ON
}
// 0=16ms, 1=32ms,2=64ms,3=128ms,4=250ms,5=500ms
// 6=1 sec,7=2 sec, 8=4 sec, 9= 8sec
void setup_watchdog(int ii) {
  byte bb;
  int ww;
  if (ii > 9 ) ii=9;
  bb=ii & 7;
  if (ii > 7) bb|= (1<<5);
  bb|= (1<<WDCE);
  ww=bb;
  MCUSR &= ~(1<<WDRF);
  // start timed sequence
  WDTCR |= (1<<WDCE) | (1<<WDE);
  // set new watchdog timeout value
  WDTCR = bb;
  WDTCR |= _BV(WDIE);
}
 
// Watchdog Interrupt Service / is executed when watchdog timed out
ISR(WDT_vect) {
  counter++;
  f_wdt=1;  // set global flag
}