diff --git a/cyassl/ctaocrypt/settings.h b/cyassl/ctaocrypt/settings.h
index c466accad..5f81c970e 100644
--- a/cyassl/ctaocrypt/settings.h
+++ b/cyassl/ctaocrypt/settings.h
@@ -186,6 +186,7 @@
     #include "rand.h"
     #define FREERTOS
     #define NO_FILESYSTEM
+    #define NO_MAIN_DRIVER
     #define CYASSL_USER_IO
     #define NO_DEV_RANDOM
     #define HAVE_ECC