Dead Drop for Adventure Games

#define F_CPU 1000000UL

#include <avr/io.h>
#include <util/delay.h>

// Define the I/O port to be used for the LED.
#define GREEN PB0
#define RED PB1

// timing
#define DOT 400
#define DASH 1200
#define PAUSE 400
#define NEW_CHAR_PAUSE 1800

// to make it simple all letters are normalized to 4 items
#define LETTER_SIZE 4

// 0 means no action
#define A {DOT, DASH, 0, 0}
#define B {DASH, DOT, DOT, DOT}
#define C {DASH, DOT, DASH, DOT}
#define D {DASH, DOT, DOT, 0}
#define E {DOT, 0, 0, 0}
#define F {DOT, DOT, DASH, DOT}
#define G {DASH, DASH, DOT, 0}
#define H {DOT, DOT, DOT, DOT}
#define I {DOT, DOT, 0, 0}
#define J {DOT, DASH, DASH, DASH}
#define K {DASH, DOT, DASH, 0}
#define L {DOT, DASH, DOT, DOT}
#define M {DASH, DASH, 0, 0}
#define N {DASH, DOT, 0, 0}
#define O {DASH, DASH, DASH, 0}
#define P {DOT, DASH, DASH, DOT}
#define Q {DASH, DASH, DOT, DASH}
#define R {DOT, DASH, DOT, 0}
#define S {DOT, DOT, DOT, 0}
#define T {DASH, 0, 0, 0}
#define U {DOT, DOT, DASH, 0}
#define V {DOT, DOT, DOT, DASH}
#define W {DOT, DASH, DASH, 0}
#define X {DASH, DOT, DOT, DASH}
#define Y {DASH, DOT, DASH, DASH}
#define Z {DASH, DASH, DOT, DOT}

// here you can create message to show
#define MESSAGE_SIZE 5
const int message[MESSAGE_SIZE][LETTER_SIZE] = {H, E, L, L, O};

int main(void) {
	// Set the LED port number as output.
	// The DDRB is the data direction for port B.
	// What this does is:
	//  - shifts the "1" on left, N-times depending on the LED1_PORT value; and ...
	//  - does bitwise "OR" with the value in the port register DDRB.
	DDRB |= (1 << GREEN) | (1 << RED);

	// Begin an infinite loop. This is how most programs work.
	while (1) {
		// Set the LED port bit to "1" - LED will be turned on.
		// This is bitwise "OR" operation with "1".
		// Green LED shows start of message
		PORTB |= (1 << GREEN);
		_delay_ms(1000);
		PORTB &= ~(1 << GREEN) ;
		_delay_ms(400);

		int i, j;
		for (i = 0; i < MESSAGE_SIZE; i++)
		{
			for (j = 0; j < LETTER_SIZE; j++)
			{
				PORTB |= (1 << RED);
				// __builtin_avr_delay_cycles expects a compile time integer constant
				if (message[i][j] == DOT)
				{
					_delay_ms(DOT);
				}
				else if (message[i][j] == DASH) 
				{
					_delay_ms(DASH);					
				}				
				PORTB &= ~(1 << RED) ;
				_delay_ms(PAUSE);
			}
			_delay_ms(NEW_CHAR_PAUSE);
		}
	}

	return (0);
}