int numerator = 5:
unsigned char denominators[256] = {
  5,   5,   5,   5,   5,   5,   5,   6,   6,   6,   6,   6,   6,   6,   6,   6, 
  6,   6,   7,   7,   7,   7,   7,   7,   7,   7,   7,   8,   8,   8,   8,   8, 
  8,   8,   8,   9,   9,   9,   9,   9,   9,   9,  10,  10,  10,  10,  10,  10, 
 10,  11,  11,  11,  11,  11,  11,  12,  12,  12,  12,  12,  13,  13,  13,  13, 
 13,  14,  14,  14,  14,  14,  15,  15,  15,  15,  16,  16,  16,  16,  17,  17, 
 17,  17,  18,  18,  18,  19,  19,  19,  19,  20,  20,  20,  21,  21,  21,  22, 
 22,  22,  23,  23,  23,  24,  24,  24,  25,  25,  26,  26,  26,  27,  27,  28, 
 28,  29,  29,  29,  30,  30,  31,  31,  32,  32,  33,  33,  34,  34,  35,  35, 
 36,  37,  37,  38,  38,  39,  39,  40,  41,  41,  42,  43,  43,  44,  45,  45, 
 46,  47,  47,  48,  49,  50,  51,  51,  52,  53,  54,  55,  55,  56,  57,  58, 
 59,  60,  61,  62,  63,  64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74, 
 75,  77,  78,  79,  80,  81,  83,  84,  85,  87,  88,  89,  91,  92,  94,  95, 
 97,  98, 100, 101, 103, 104, 106, 108, 109, 111, 113, 114, 116, 118, 120, 122, 
124, 125, 127, 129, 131, 133, 136, 138, 140, 142, 144, 146, 149, 151, 153, 156, 
158, 161, 163, 166, 168, 171, 173, 176, 179, 182, 184, 187, 190, 193, 196, 199, 
202, 205, 209, 212, 215, 219, 222, 225, 229, 232, 236, 240, 243, 247, 251, 255  };


int lfo(int speed)
{
	static int current_e = 0;
	static int current_level = 128 ;
	static int direction = 1;	/* 1:up, -1:down*/
	static int last_speed = 0 ;

	if (last_speed != speed ){	/*is there changeing speed?*/
		last_speed = speed;
		current_e= 0;
	}

	current_e += numerator;
	if (current_e>= denominators[speed] ){
		current_e -= denominators[speed] ;
		current_level += direction;
	}
	if (current_level > 255 ){	/*max should be 256*/
		direction = -1;
		current_e = 0;
		current_level -= 1 ;
	}
	if (current_level == 0){
		direction = +1;
		current_e = 0;
		current_level += 1;
	}
	return current_level;
}

main ()
{
	int i;
	int cnt = 0;

	for (i = 0 ; i < 256*256 ; i++ ){ 
		printf ("%d\n", lfo(0) );
	}
}