diff --git a/Core/Src/freertos.c b/Core/Src/freertos.c
index 406480d..3af5a97 100644
--- a/Core/Src/freertos.c
+++ b/Core/Src/freertos.c
@@ -312,15 +312,15 @@ void StartButtonDetect(void *argument)
   /* Infinite loop */
   for(;;)
   {
-	  //长按�???????�???????
 	  if(NaviKit.sys.power_btn == true)
 	  {//power btn has been pushed
-		  osDelay(2000);
+		  osDelay(1000);
 		  if(NaviKit.sys.power_btn == true)
-		  {//power btn has been pushed more than 2000 ms
+		  {//power btn has been pushed more than 1000 ms
 			  if(NaviKit.sys.sta == runing)
 			  {//system is runing now, user request to shutdown
           enter_shutdown_state();
+          NaviKit.sys.sta = shutdown;
 				  printf("shutdown \n");
 				  Beep(50);
 
@@ -328,7 +328,7 @@ void StartButtonDetect(void *argument)
 			  }
 			  else if(NaviKit.sys.sta == shutdown)
 			  {//system is shutdown now , user request to power on
-          enter_runing_state();
+				  NaviKit.sys.sta = runing;
 				  printf("power on \n");
 				  Beep(200);
 				  osDelay(500);
@@ -339,20 +339,20 @@ void StartButtonDetect(void *argument)
       {
         if(NaviKit.sys.sta == runing)
         {
-          enter_sleep_state();
+          NaviKit.sys.sta = sleep;
         }
         else if(NaviKit.sys.sta == sleep)
         {
-          enter_runing_state();
+          NaviKit.sys.sta = runing;
         }
         
       }
 	  }
 	  if(NaviKit.sys.custom_btn == true )
 	  {//custom button has been pushed
-		  osDelay(2000);
+		  osDelay(1000);
 		  if(NaviKit.sys.custom_btn == true )
-		  {//custom button has been pushed over 2000 ms
+		  {//custom button has been pushed over 1000 ms
 			  if(NaviKit.sys.sta == runing)
 			  {
             // restart();
@@ -414,15 +414,18 @@ void StartStateSwitchTask(void *argument)
 	  switch(NaviKit.sys.sta)
 	  {
       case shutdown:
-      {
-        
+      {//only from runing state
+        if(NaviKit.sys.last_sta == runing)
+          enter_shutdown_state();
       }break;
       case runing:
-      {
-        
+      {//from sleep and shutdown state
+        enter_runing_state();
       }break;
       case sleep:
-      {
+      {//only form runing state
+        if(NaviKit.sys.last_sta == runing)
+          enter_sleep_state();
 
       }break;
 	  }
@@ -451,11 +454,8 @@ void StartSOMPowerManageTask(void *argument)
 
 /* Private application code --------------------------------------------------*/
 /* USER CODE BEGIN Application */
-void sys_start()
-{
-				  
-          
-}
+
+
 //power off by button pushed
 void force_sys_stop()
 {
@@ -516,12 +516,9 @@ void enter_shutdown_state()
 
     HAL_GPIO_WritePin(PMB_PS_ON_GPIO_Port ,PMB_PS_ON_Pin, GPIO_PIN_RESET);                    osDelay(100);
 
-	  NaviKit.sys.sta = shutdown;
 }
 void enter_sleep_state()
 {
-  
-    
     // HAL_GPIO_WritePin(SOC_U3_HUB_PWR_CTL_GPIO_Port,SOC_U3_HUB_PWR_CTL_Pin, GPIO_PIN_RESET);				  osDelay(100);
     HAL_GPIO_WritePin(SOC_U2_HUB_PWR_CTL_GPIO_Port,SOC_U2_HUB_PWR_CTL_Pin, GPIO_PIN_RESET);				  osDelay(100);
     HAL_GPIO_WritePin(SOC_U3_HOST_PWR_CTL_GPIO_Port,SOC_U3_HOST_PWR_CTL_Pin, GPIO_PIN_RESET);				osDelay(100);
@@ -547,14 +544,10 @@ void enter_sleep_state()
     HAL_GPIO_WritePin(SYS_FAN_CTL_2_GPIO_Port,SYS_FAN_CTL_2_Pin,GPIO_PIN_RESET);                 osDelay(100);
     HAL_GPIO_WritePin(SYS_FAN_CTL_3_GPIO_Port,SYS_FAN_CTL_3_Pin,GPIO_PIN_RESET);                 osDelay(100);
     
-	  NaviKit.sys.sta = sleep;
 
 }
 void enter_runing_state()
 {
-  NaviKit.sys.sta = runing;
-
-  Beep(40);
   HAL_GPIO_WritePin(PMB_PS_ON_GPIO_Port ,PMB_PS_ON_Pin, GPIO_PIN_SET);                osDelay(100);
 
   HAL_GPIO_WritePin(SYS_FAN_CTL_1_GPIO_Port,SYS_FAN_CTL_1_Pin,GPIO_PIN_SET);                 osDelay(100);
@@ -586,7 +579,7 @@ void enter_runing_state()
 }
 
 
-
+//printf redefine
 #ifdef __GNUC__
 #define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
 PUTCHAR_PROTOTYPE