diff --git a/README.md b/README.md
index e7471a3..aa64752 100644
--- a/README.md
+++ b/README.md
@@ -31,3 +31,9 @@
  `stm32f1xx_hal_pcd.c文件内`
  `void HAL_PCD_IRQHandler(PCD_HandleTypeDef *hpcd)函数内` 
  `HAL_PCD_SuspendCallback(hpcd) 代码段` 务必屏蔽，否则导致枚举失败，提示获取设备描述符失败。
+
+
+* 开关机
+ 开机：关机状态下，长按电源按钮1s，滴声后松开
+ 关机：开机/DFU状态下，长按电源按钮1s，滴声后松开
+ DFU：关机状态下，先按住重启按钮，然后按住电源按钮，滴声后松开两个按钮
diff --git a/power_state_machine.jpg b/power_state_machine.jpg
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