diff --git a/register_printer/templates/c_header_sys.h b/register_printer/templates/c_header_sys.h
index c907a4c..3135f64 100644
--- a/register_printer/templates/c_header_sys.h
+++ b/register_printer/templates/c_header_sys.h
@@ -9,7 +9,7 @@
 #define  {{ "%s_BASE\t\t0x%x" | format(block_instance.name, block_instance.base_address) }}
 #define  {{ "%s\t\t((%s_TypeDef  *)\t\t%s_BASE)" | format(
     block_instance.name,
-    block_instance.type,
+    block_instance.type.upper(),
     block_instance.name)
 }}