diff --git a/code/base/test_base.h b/code/base/test_base.h
index 7dbb10a..6000aca 100644
--- a/code/base/test_base.h
+++ b/code/base/test_base.h
@@ -233,6 +233,7 @@ enum write_cat
     WRITE_CAT_PID,          // val = (int*)
     WRITE_CAT_SPEED,        // val = (int*)
     WRITE_CAT_SLEEP,        // val = (int*)
+    WRITE_CAT_SERIALNUM     // val = (char*)
 };
 
 typedef struct _write_cfg