diff --git a/win32_functional_tests/chconf.h b/win32_functional_tests/chconf.h
index 2f29bf9e75..76ab9217a0 100644
--- a/win32_functional_tests/chconf.h
+++ b/win32_functional_tests/chconf.h
@@ -28,6 +28,8 @@
 #ifndef _CHCONF_H_
 #define _CHCONF_H_
 
+#define CHPRINTF_USE_FLOAT          	TRUE
+
 /*===========================================================================*/
 /**
  * @name System timers settings