diff --git a/Core/Inc/navikit.h b/Core/Inc/navikit.h
index dd3aa3d..f7cd74b 100644
--- a/Core/Inc/navikit.h
+++ b/Core/Inc/navikit.h
@@ -27,6 +27,7 @@
 
 typedef enum
 {
+	standby,	//minimum current state
 	idle,	//only mcu runing
 	run, 		//all function runing
 	sleep, 		//SOCs and FANs are stop
@@ -136,6 +137,7 @@ bool PWR_Status(enum Device_t device);
 void NaviKit_var_init();
 
 //power state machine switch function
+void enter_standby_state();
 void enter_isp_state();
 void enter_run_state(uint16_t delay);
 void enter_idle_state(uint16_t delay);