diff --git a/Core/Src/main.c b/Core/Src/main.c
index 0cbcd62..1d2cf4f 100644
--- a/Core/Src/main.c
+++ b/Core/Src/main.c
@@ -86,6 +86,9 @@ int _write(int file, char *ptr, int len)
 }
 
 #ifndef DEBUG_ITM
+#include <stdio.h>
+#include <stdarg.h>
+
 void uart_debug_print(const char *fmt, ...)
 {
   char buf[128];