HELLO WORLD from Arduino

hello.c

#define LED 13
#define T 100 // speed

char *morse_pattern[] = {
  "._", "_...", "_._.", "_..", ".", ".._.", "__.",
  "....", "..", ".___", "_._", "._..", "__",
  "_.", "___", ".__.", "__._", "._.", "...", "_",
  ".._", "..._", ".__", "_.._", "__._", "__.."
};

void setup() {                
  pinMode(LED, OUTPUT);
  digitalWrite(LED, LOW);
  delay(T*7);
}

void morse(int output, int time, char *str) {
  int i, j;

  for (i=0; i<strlen(str); i++) {
    char *c = str+i;
    if ('A' <= *c && *c <= 'Z') {
      char *pattern = morse_pattern[*c - 'A'];
      for (j=0; j<strlen(pattern); j++) {
        digitalWrite(output, HIGH);
        if(pattern[j] == '.') {
          delay(time * 1);
        } 
        else {
          delay(time * 3);
        }
        digitalWrite(output, LOW);
        delay(time * 1);
      }
      delay(time * 2);
    } else {
      delay(time * 3);
    }
  }
  delay(time * 4);
}

void loop() {
  char *str = "HELLO WORLD";
  morse(LED, T, str);
}