diff --git a/Core/Src/usart.c b/Core/Src/usart.c
index cb86f56..578df0b 100644
--- a/Core/Src/usart.c
+++ b/Core/Src/usart.c
@@ -6,7 +6,7 @@
   ******************************************************************************
   * @attention
   *
-  * <h2><center>&copy; Copyright (c) 2020 STMicroelectronics.
+  * <h2><center>&copy; Copyright (c) 2021 STMicroelectronics.
   * All rights reserved.</center></h2>
   *
   * This software component is licensed by ST under Ultimate Liberty license
@@ -32,7 +32,7 @@ void MX_UART4_Init(void)
 {
 
   huart4.Instance = UART4;
-  huart4.Init.BaudRate = 115200;
+  huart4.Init.BaudRate = 56000;
   huart4.Init.WordLength = UART_WORDLENGTH_8B;
   huart4.Init.StopBits = UART_STOPBITS_1;
   huart4.Init.Parity = UART_PARITY_NONE;
@@ -51,7 +51,7 @@ void MX_USART1_UART_Init(void)
 {
 
   huart1.Instance = USART1;
-  huart1.Init.BaudRate = 115200;
+  huart1.Init.BaudRate = 56000;
   huart1.Init.WordLength = UART_WORDLENGTH_8B;
   huart1.Init.StopBits = UART_STOPBITS_1;
   huart1.Init.Parity = UART_PARITY_NONE;
@@ -172,7 +172,23 @@ void HAL_UART_MspDeInit(UART_HandleTypeDef* uartHandle)
 
 /* USER CODE BEGIN 1 */
 
+//printf redirect
+#ifdef __GNUC__
+//#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
+#define PUTCHAR_PROTOTYPE int putchar(int ch)
+#else
+#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
+#endif
 
+PUTCHAR_PROTOTYPE
+{
+//	uint8_t time_out=3;
+//	while(!__HAL_UART_GET_FLAG(&huart1,UART_FLAG_TXE) && time_out--){
+//		HAL_Delay(1);
+//	}
+	HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,100);
+	return ch;
+}
 
 /* USER CODE END 1 */
 
diff --git a/README.md b/README.md
index 4eab4ef..1dde20d 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
  * @Author: CK.Zh
  * @Date: 2020-02-20 11:39:38
  * @LastEditors: CK.Zh
- * @LastEditTime: 2020-04-30 10:15:25
+ * @LastEditTime: 2021-01-05 16:21:59
  -->
 # NaviKit_stm32
  PM1导航套件中电源控制板源码，STM32F107VCT6，开发环境STM32CubeIDE
@@ -32,3 +32,4 @@
  `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。
 
+ > EC日志输出口波特率为56000bps
\ No newline at end of file