diff --git a/Day3/README.md b/Day3/README.md
index 50a90be..ab9a182 100644
--- a/Day3/README.md
+++ b/Day3/README.md
@@ -181,7 +181,16 @@ dist 的好处
 pkgs --update
 ```
 
-## 示例点灯
+## 示例灭灯
 ### 灭了怎么点都不亮
-在key线程循环中每次点亮？
-因为按键按灭就没再点亮
\ No newline at end of file
+因为按键按灭就没再点亮
+在key线程循环开始每次点亮？
+### 灯轻微闪烁，几乎看不出
+不能及时获取？用无等待获取信号量？
+### 还是一样……
+因为采用了延时防止误触，判断是否按下按键花了一点时间
+~~只要知道按键没有按下就亮灯就行~~
+在下次判断按键没按下之后再亮灯
+### 居然在按键的线程在控制led
+改为没摁才释放信号量，led线程获取到后设为亮灯
+并在获取信号量前将led设为灭灯
diff --git a/applications/main.c b/applications/main.c
index a8eac1d..f4b27b6 100644
--- a/applications/main.c
+++ b/applications/main.c
@@ -79,23 +79,22 @@ static void key_name_entry(void *parameter)
     rt_uint32_t count=0;
     while (1)
     {
-        
         if(rt_pin_read(PIN_KEY0) == PIN_LOW)
         {
             rt_thread_mdelay(100);
             if(rt_pin_read(PIN_KEY0) == PIN_LOW)
             {
-                rt_kprintf("key0 is pressed (%d)\r", count++);
-                    rt_sem_release(dynamic_sem);
+                rt_kprintf("key0 is pressed (%d) ", count++);
+                    // rt_sem_release(dynamic_sem);
             }
             else
             {
-                rt_pin_write(GPIO_LED_R, PIN_LOW);
+                rt_sem_release(dynamic_sem);
             }
         }
         else
         {
-            rt_pin_write(GPIO_LED_R, PIN_LOW);
+            rt_sem_release(dynamic_sem);
         }
         rt_thread_mdelay(10);
     }
@@ -108,15 +107,11 @@ static void led_name_entry(void *parameter)
     rt_uint32_t result=0;
     while (1)
     {
+        rt_pin_write(GPIO_LED_R, PIN_HIGH);
         result = rt_sem_take(dynamic_sem, RT_WAITING_FOREVER);
         if (result == RT_EOK)
-        {
-            rt_kprintf("LED HIGH\n");
-            rt_pin_write(GPIO_LED_R, PIN_HIGH);
-        }
-        else 
-        {
-            rt_kprintf("LED LOW");
+        {            
+            // rt_kprintf("LED LOW\n");
             rt_pin_write(GPIO_LED_R, PIN_LOW);
         }