diff --git a/README.md b/README.md
index a5a9790..94b598a 100644
--- a/README.md
+++ b/README.md
@@ -22,6 +22,7 @@ If you make use of my code or have questions, please let me know.
 - only byte mode supported
 - no automatic mask pattern evaluation
 - tested only for version 2, level L and M QR codes (25x25)
+- memory organization and pixel drawing and checking has to be implemented platform specific
 
 ## License
 Copyright © 2021 Thomas Jentzsch. (GPLV3 License)