#define LED_CNT 20
#define TIME_STEP 10    // Millisekunden

typedef struct {
  unsigned int pin;
  unsigned int period;
  unsigned int duty;  
  unsigned int cnt;
} led_t;

// Definition der LED-Blinkmuster
// Periodendauer und Leuchtdauer in 10ms Schritten

led_t leds[LED_CNT] = {
// IO-Pin, Periode, Leuchtdauer, Zaehler
  {1, 20, 10, 1000},
  {2, 30, 5, 1000},
  {3, 40, 3, 1000},
  {4, 99, 50, 1000},
  {5, 77, 60, 1000},
  {6, 66, 60, 1000},
  {7, 88, 5, 1000},
  {9, 101, 50, 1000},
  {10, 200, 100, 1000},
  {11, 300, 10, 1000},
  {12, 400, 350, 1000},
  {13, 500, 250, 1000},
  {14, 1000, 100, 1000},
  {15, 999, 100, 1000},
  {16, 777, 100, 1000},
  {17, 888, 100, 1000},
  {18, 444, 100, 1000},
  {19, 333, 100, 1000},
  {20, 111, 100, 1000}
};

void led_multi() {
  int i;
  
  for (i=1; i < LED_CNT; i++) {
    leds[i].cnt++;
    if (leds[i].cnt >= leds[i].period) {         
      leds[i].cnt = 0;
      if (leds[i].duty != 0) {
        digitalWrite(leds[i].pin, HIGH);
      }
    } else {
      if (leds[i].cnt == leds[i].duty) {
        digitalWrite(leds[i].pin, LOW);
      }      
    }    
  }
}

void setup() {
  int i;

  for (i=0; i < LED_CNT; i++) {
    pinMode(leds[i].pin, OUTPUT);
  }
}

void loop() {
  static unsigned long last, now;

  // alle TIME_STEP ms die LED-Funktion aufrufen
  
  now = millis();
  if ( (now - last) >= TIME_STEP) {
    last += TIME_STEP;
    led_multi();
  }
}