diff --git a/cpu/msp430/dev/uart0x.c b/cpu/msp430/dev/uart0x.c
index bb452e674..f8abd5b3b 100644
--- a/cpu/msp430/dev/uart0x.c
+++ b/cpu/msp430/dev/uart0x.c
@@ -34,6 +34,7 @@
  */
 
 #include <stdlib.h>
+#include <io.h>
 #include <signal.h>
 
 #include "sys/energest.h"