diff --git a/light_manager.py b/light_manager.py
index ecdf29f..09a1fe3 100644
--- a/light_manager.py
+++ b/light_manager.py
@@ -33,6 +33,9 @@ class LightStrip:
     np = self.np
     t = self.cur_tick
     n = np.n
+    
+    if not len(self.cur_pattern) >= n - 1:
+      self.get_next_pattern_tick()
     changes = 0
     ind = self.cur_index
     for i in range(ind, n):