diff --git a/bsp/stm32f0x/drivers/usart.c b/bsp/stm32f0x/drivers/usart.c
index 0c4aa15821c021c402ebbafbbc80e95438fdfb6a..56e39f1c94b81bc8aeb543dcdfd27cf600b1a4fc 100644
--- a/bsp/stm32f0x/drivers/usart.c
+++ b/bsp/stm32f0x/drivers/usart.c
@@ -97,8 +97,9 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
 
-    while (!(uart->uart_device->ISR & USART_FLAG_TXE));
+    USART_ClearFlag(uart->uart_device,USART_FLAG_TC);
     uart->uart_device->TDR = c;
+    while (!(uart->uart_device->ISR & USART_FLAG_TC));
 
     return 1;
 }
diff --git a/bsp/stm32f107/drivers/usart.c b/bsp/stm32f107/drivers/usart.c
index c1bdd1b9be053c19b504e9495f84840166718139..e6a7d59535cd738e06433868e7356064b3da7498 100644
--- a/bsp/stm32f107/drivers/usart.c
+++ b/bsp/stm32f107/drivers/usart.c
@@ -124,6 +124,7 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
 
+    USART_ClearFlag(uart->uart_device,USART_FLAG_TC);
     uart->uart_device->DR = c;
     while (!(uart->uart_device->SR & USART_FLAG_TC));
 
diff --git a/bsp/stm32f10x-HAL/drivers/drv_usart.c b/bsp/stm32f10x-HAL/drivers/drv_usart.c
index 265046992127efaa80103152181548af46721bfb..bd6b6cd984f45599889b76e1ace5e5dcf88fa58f 100644
--- a/bsp/stm32f10x-HAL/drivers/drv_usart.c
+++ b/bsp/stm32f10x-HAL/drivers/drv_usart.c
@@ -113,8 +113,9 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     struct stm32_uart *uart;
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
-    while (__HAL_UART_GET_FLAG(&uart->huart, UART_FLAG_TXE) == RESET);
+    __HAL_UART_CLEAR_FLAG(&(uart->huart), UART_FLAG_TC);
     uart->huart.Instance->DR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->huart), UART_FLAG_TC) == RESET);
     return 1;
 }
 
diff --git a/bsp/stm32f10x/drivers/usart.c b/bsp/stm32f10x/drivers/usart.c
index 18059bf1dc75f2fd29b88b67c43f4abf401dab35..b3960d749ace1bfc08b7a310ba8a38bc5fd56915 100644
--- a/bsp/stm32f10x/drivers/usart.c
+++ b/bsp/stm32f10x/drivers/usart.c
@@ -100,8 +100,6 @@ static rt_err_t stm32_configure(struct rt_serial_device *serial, struct serial_c
 
     /* Enable USART */
     USART_Cmd(uart->uart_device, ENABLE);
-    
-    USART_ClearFlag(uart->uart_device,USART_FLAG_TC);
 
     return RT_EOK;
 }
@@ -159,6 +157,7 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     }
     else
     {
+        USART_ClearFlag(uart->uart_device,USART_FLAG_TC);
         uart->uart_device->DR = c;
         while (!(uart->uart_device->SR & USART_FLAG_TC));
     }
diff --git a/bsp/stm32f40x/drivers/usart.c b/bsp/stm32f40x/drivers/usart.c
index 0633c82cdd8191767fb693a32d1332c28a84d36e..bd8ea3239b61f2a24455c8aa94f3fe83612030dc 100644
--- a/bsp/stm32f40x/drivers/usart.c
+++ b/bsp/stm32f40x/drivers/usart.c
@@ -166,8 +166,9 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
 
-    while (!(uart->uart_device->SR & USART_FLAG_TXE));
+    USART_ClearFlag(uart->uart_device,USART_FLAG_TC);
     uart->uart_device->DR = c;
+    while (!(uart->uart_device->SR & USART_FLAG_TC));
 
     return 1;
 }
diff --git a/bsp/stm32f411-nucleo/drivers/drv_usart.c b/bsp/stm32f411-nucleo/drivers/drv_usart.c
index a0a00886942828564564ef4c963e16a9ae3ac80a..dacd1490ebe119d2af1a77a4c951a5e3d5623706 100644
--- a/bsp/stm32f411-nucleo/drivers/drv_usart.c
+++ b/bsp/stm32f411-nucleo/drivers/drv_usart.c
@@ -155,8 +155,9 @@ static int drv_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct drv_uart *)serial->parent.user_data;
     
-    while((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_TXE) == RESET));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->DR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
     return 1;
 }
 
diff --git a/bsp/stm32f429-apollo/drivers/usart.c b/bsp/stm32f429-apollo/drivers/usart.c
index ecca8b7307244e22527d280eb472f51ca9b0de9b..5ed0100dc3e2344bee98e3aea6d943d971678876 100644
--- a/bsp/stm32f429-apollo/drivers/usart.c
+++ b/bsp/stm32f429-apollo/drivers/usart.c
@@ -185,8 +185,9 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
 
-    while((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_TXE) == RESET));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->DR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
     return 1;
 }
 
diff --git a/bsp/stm32f429-armfly/drivers/usart.c b/bsp/stm32f429-armfly/drivers/usart.c
index ecca8b7307244e22527d280eb472f51ca9b0de9b..5ed0100dc3e2344bee98e3aea6d943d971678876 100644
--- a/bsp/stm32f429-armfly/drivers/usart.c
+++ b/bsp/stm32f429-armfly/drivers/usart.c
@@ -185,8 +185,9 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
 
-    while((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_TXE) == RESET));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->DR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
     return 1;
 }
 
diff --git a/bsp/stm32f429-disco/drivers/usart.c b/bsp/stm32f429-disco/drivers/usart.c
index f7ba2ed277e7472682844a5ee41b88415505eec3..7509cbf64c34f4b0d87f9a1b93ca04732fd1c4e1 100644
--- a/bsp/stm32f429-disco/drivers/usart.c
+++ b/bsp/stm32f429-disco/drivers/usart.c
@@ -185,8 +185,9 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
 
-    while((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_TXE) == RESET));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->DR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
     return 1;
 }
 
diff --git a/bsp/stm32f4xx-HAL/drivers/drv_usart.c b/bsp/stm32f4xx-HAL/drivers/drv_usart.c
index db3321ab349239458ecf06f5489bd94d6dd29cb7..083cdfc39bc74a2d6ad5937662aaec05e4f208da 100644
--- a/bsp/stm32f4xx-HAL/drivers/drv_usart.c
+++ b/bsp/stm32f4xx-HAL/drivers/drv_usart.c
@@ -122,8 +122,9 @@ static int drv_putc(struct rt_serial_device *serial, char c)
     struct drv_uart *uart;
     RT_ASSERT(serial != RT_NULL);
     uart = (struct drv_uart *)serial->parent.user_data;
-    while ((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_TXE) == RESET));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->DR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
     return 1;
 }
 
diff --git a/bsp/stm32f7-disco/drivers/drv_usart.c b/bsp/stm32f7-disco/drivers/drv_usart.c
index 5d54d6903b6cc622a6edde3ed6bdde2e3b62fbc7..2c15fafc2988aa8f5f9fbdb25371c40ef2df26e7 100644
--- a/bsp/stm32f7-disco/drivers/drv_usart.c
+++ b/bsp/stm32f7-disco/drivers/drv_usart.c
@@ -106,7 +106,7 @@ static int drv_putc(struct rt_serial_device *serial, char c)
     struct drv_uart *uart;
     RT_ASSERT(serial != RT_NULL);
     uart = (struct drv_uart *)serial->parent.user_data;
-    while ((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_TXE) == RESET));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->TDR = c;
     return 1;
 }
diff --git a/bsp/stm32h743-nucleo/drivers/drv_usart.c b/bsp/stm32h743-nucleo/drivers/drv_usart.c
index e8620b65eee6c47c33d31ca909c636dea5f11da9..26b624130e7f2da7b0833392c0b7f3cdef3ad223 100644
--- a/bsp/stm32h743-nucleo/drivers/drv_usart.c
+++ b/bsp/stm32h743-nucleo/drivers/drv_usart.c
@@ -138,8 +138,9 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
 
-    while (!(uart->UartHandle.Instance->ISR & UART_FLAG_TXE));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->TDR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
 
     return 1;
 }
diff --git a/bsp/stm32l475-iot-disco/drivers/usart.c b/bsp/stm32l475-iot-disco/drivers/usart.c
index fa5a68e7cb7cca357920d8af91cd67d955ae1d19..15f52ecedb85e194cb86cbf3d62df96f6ba3f071 100644
--- a/bsp/stm32l475-iot-disco/drivers/usart.c
+++ b/bsp/stm32l475-iot-disco/drivers/usart.c
@@ -185,8 +185,9 @@ static int stm32_putc(struct rt_serial_device *serial, char c)
     RT_ASSERT(serial != RT_NULL);
     uart = (struct stm32_uart *)serial->parent.user_data;
 
-    while((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_TXE) == RESET));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->TDR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
     return 1;
 }
 
diff --git a/bsp/stm32l476-nucleo/drivers/drv_usart.c b/bsp/stm32l476-nucleo/drivers/drv_usart.c
index c5f5e728a3f66d82f12c4d881b6118d23f3cc10e..a4ec08db077feb6641d184381c4026c0b57bc2c9 100644
--- a/bsp/stm32l476-nucleo/drivers/drv_usart.c
+++ b/bsp/stm32l476-nucleo/drivers/drv_usart.c
@@ -141,8 +141,9 @@ static int drv_putc(struct rt_serial_device *serial, char c)
 
     uart = (struct drv_uart *)serial->parent.user_data;
 
-    while ((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_TXE) == RESET));
+    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
     uart->UartHandle.Instance->TDR = c;
+    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
 
     return 1;
 }