diff --git a/led-badge-11x44.py b/led-badge-11x44.py
index a260d1b..0b32a04 100755
--- a/led-badge-11x44.py
+++ b/led-badge-11x44.py
@@ -475,6 +475,10 @@ if needpadding:
 
 # print(buf)      # array('B', [119, 97, 110, 103, 0, 0, 0, 0, 48, 48, 48, 48, 48, 48, 48, 48, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 60, 126, 255, 255, 255, 255, 126, 60, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
 
+if len(buf) > 8192:
+  print ("Writing more than 8192 bytes damages the display!")
+  sys.exit(1)
+
 if have_pyhidapi:
   pyhidapi.hid_write(dev, buf)
 else: