diff --git a/README.md b/README.md
index da5b8e8..0ff3c42 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@ I finally understand how CISC processors work, I've played Turing Complete and b
 - [x] Disassembler
 - [x] Understanding the i8080 machine code
 - [x] Emulating the i8080
-- [ ] I/O-functionality
+- [x] I/O-functionality
 
 -------diverging from the guide--------