diff --git a/ROM2/crctest.c b/ROM2/crctest.c
index a67ed9b22afcc9a017529dcd8af09700d45ceb40..1356a25770c0f7f0ebf518f662b4ccdaa9b923b7 100644
--- a/ROM2/crctest.c
+++ b/ROM2/crctest.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 typedef unsigned short u16;
 typedef unsigned char bool;
 #include "crctab.h"