diff --git a/minichlink/minichlink.c b/minichlink/minichlink.c
index 4169e2125093b65f854fc9083bca6ccb63978235..1bc84286c9b3d88eda57f4f1181a6e3579946f31 100644
--- a/minichlink/minichlink.c
+++ b/minichlink/minichlink.c
@@ -12,6 +12,7 @@
 #include "../ch32v003fun/ch32v003fun.h"
 
 #if defined(WINDOWS) || defined(WIN32) || defined(_WIN32)
+void Sleep(uint32_t dwMilliseconds);
 #else
 #include <unistd.h>
 #endif