CUBEMAX生成的usart.c檔案修改如下,沒有效率強迫症的人可以參考

/**
  ******************************************************************************
  * File Name          : USART.c
  * Description        : This file provides code for the configuration
  *                      of the USART instances.
  ******************************************************************************
  * This notice applies to any and all portions of this file
  * that are not between comment pairs USER CODE BEGIN and
  * USER CODE END. Other portions of this file, whether 
  * inserted by the user or by software development tools
  * are owned by their respective copyright owners.
  *
  * Copyright (c) 2018 STMicroelectronics International N.V. 
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without 
  * modification, are permitted, provided that the following conditions are met:
  *
  * 1. Redistribution of source code must retain the above copyright notice, 
  *    this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright notice,
  *    this list of conditions and the following disclaimer in the documentation
  *    and/or other materials provided with the distribution.
  * 3. Neither the name of STMicroelectronics nor the names of other 
  *    contributors to this software may be used to endorse or promote products 
  *    derived from this software without specific written permission.
  * 4. This software, including modifications and/or derivative works of this 
  *    software, must execute solely and exclusively on microcontroller or
  *    microprocessor devices manufactured by or for STMicroelectronics.
  * 5. Redistribution and use of this software other than as permitted under 
  *    this license is void and will automatically terminate your rights under 
  *    this license. 
  *
  * THIS SOFTWARE IS PROVIDED BY STMICROELECTRONICS AND CONTRIBUTORS "AS IS" 
  * AND ANY EXPRESS, IMPLIED OR STATUTORY WARRANTIES, INCLUDING, BUT NOT 
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 
  * PARTICULAR PURPOSE AND NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY
  * RIGHTS ARE DISCLAIMED TO THE FULLEST EXTENT PERMITTED BY LAW. IN NO EVENT 
  * SHALL STMICROELECTRONICS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 
  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "usart.h"

#include "gpio.h"

/* USER CODE BEGIN 0 */
void (*UART1_Callback)(uint8_t)=NULL;
void (*UART2_Callback)(uint8_t)=NULL;
void (*UART3_Callback)(uint8_t)=NULL;
uint8_t a,b,c;
/* USER CODE END 0 */

UART_HandleTypeDef huart1;
UART_HandleTypeDef huart2;
UART_HandleTypeDef huart3;

/* USART1 init function */

void MX_USART1_UART_Init(void)
{

  huart1.Instance = USART1;
  huart1.Init.BaudRate = 115200;
  huart1.Init.WordLength = UART_WORDLENGTH_8B;
  huart1.Init.StopBits = UART_STOPBITS_1;
  huart1.Init.Parity = UART_PARITY_NONE;
  huart1.Init.Mode = UART_MODE_TX_RX;
  huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart1.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart1) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

}
/* USART2 init function */

void MX_USART2_UART_Init(void)
{

  huart2.Instance = USART2;
  huart2.Init.BaudRate = 9600;
  huart2.Init.WordLength = UART_WORDLENGTH_8B;
  huart2.Init.StopBits = UART_STOPBITS_1;
  huart2.Init.Parity = UART_PARITY_NONE;
  huart2.Init.Mode = UART_MODE_TX_RX;
  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart2.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart2) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

}
/* USART3 init function */

void MX_USART3_UART_Init(void)
{

  huart3.Instance = USART3;
  huart3.Init.BaudRate = 9600;
  huart3.Init.WordLength = UART_WORDLENGTH_8B;
  huart3.Init.StopBits = UART_STOPBITS_1;
  huart3.Init.Parity = UART_PARITY_NONE;
  huart3.Init.Mode = UART_MODE_TX_RX;
  huart3.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart3.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart3) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

}

void HAL_UART_MspInit(UART_HandleTypeDef* uartHandle)
{

  GPIO_InitTypeDef GPIO_InitStruct;
  if(uartHandle->Instance==USART1)
  {
  /* USER CODE BEGIN USART1_MspInit 0 */

  /* USER CODE END USART1_MspInit 0 */
    /* USART1 clock enable */
    __HAL_RCC_USART1_CLK_ENABLE();
  
    /**USART1 GPIO Configuration    
    PA9     ------> USART1_TX
    PA10     ------> USART1_RX 
    */
    GPIO_InitStruct.Pin = GPIO_PIN_9;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_10;
    GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    /* USART1 interrupt Init */
    HAL_NVIC_SetPriority(USART1_IRQn, 5, 0);
    HAL_NVIC_EnableIRQ(USART1_IRQn);
  /* USER CODE BEGIN USART1_MspInit 1 */

  /* USER CODE END USART1_MspInit 1 */
  }
  else if(uartHandle->Instance==USART2)
  {
  /* USER CODE BEGIN USART2_MspInit 0 */

  /* USER CODE END USART2_MspInit 0 */
    /* USART2 clock enable */
    __HAL_RCC_USART2_CLK_ENABLE();
  
    /**USART2 GPIO Configuration    
    PA2     ------> USART2_TX
    PA3     ------> USART2_RX 
    */
    GPIO_InitStruct.Pin = GPIO_PIN_2;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_3;
    GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    /* USART2 interrupt Init */
    HAL_NVIC_SetPriority(USART2_IRQn, 5, 0);
    HAL_NVIC_EnableIRQ(USART2_IRQn);
  /* USER CODE BEGIN USART2_MspInit 1 */

  /* USER CODE END USART2_MspInit 1 */
  }
  else if(uartHandle->Instance==USART3)
  {
  /* USER CODE BEGIN USART3_MspInit 0 */

  /* USER CODE END USART3_MspInit 0 */
    /* USART3 clock enable */
    __HAL_RCC_USART3_CLK_ENABLE();
  
    /**USART3 GPIO Configuration    
    PB10     ------> USART3_TX
    PB11     ------> USART3_RX 
    */
    GPIO_InitStruct.Pin = GPIO_PIN_10;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_11;
    GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

    /* USART3 interrupt Init */
    HAL_NVIC_SetPriority(USART3_IRQn, 5, 0);
    HAL_NVIC_EnableIRQ(USART3_IRQn);
  /* USER CODE BEGIN USART3_MspInit 1 */

  /* USER CODE END USART3_MspInit 1 */
  }
}

void HAL_UART_MspDeInit(UART_HandleTypeDef* uartHandle)
{

  if(uartHandle->Instance==USART1)
  {
  /* USER CODE BEGIN USART1_MspDeInit 0 */

  /* USER CODE END USART1_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_USART1_CLK_DISABLE();
  
    /**USART1 GPIO Configuration    
    PA9     ------> USART1_TX
    PA10     ------> USART1_RX 
    */
    HAL_GPIO_DeInit(GPIOA, GPIO_PIN_9|GPIO_PIN_10);

    /* USART1 interrupt Deinit */
    HAL_NVIC_DisableIRQ(USART1_IRQn);
  /* USER CODE BEGIN USART1_MspDeInit 1 */

  /* USER CODE END USART1_MspDeInit 1 */
  }
  else if(uartHandle->Instance==USART2)
  {
  /* USER CODE BEGIN USART2_MspDeInit 0 */

  /* USER CODE END USART2_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_USART2_CLK_DISABLE();
  
    /**USART2 GPIO Configuration    
    PA2     ------> USART2_TX
    PA3     ------> USART2_RX 
    */
    HAL_GPIO_DeInit(GPIOA, GPIO_PIN_2|GPIO_PIN_3);

    /* USART2 interrupt Deinit */
    HAL_NVIC_DisableIRQ(USART2_IRQn);
  /* USER CODE BEGIN USART2_MspDeInit 1 */

  /* USER CODE END USART2_MspDeInit 1 */
  }
  else if(uartHandle->Instance==USART3)
  {
  /* USER CODE BEGIN USART3_MspDeInit 0 */

  /* USER CODE END USART3_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_USART3_CLK_DISABLE();
  
    /**USART3 GPIO Configuration    
    PB10     ------> USART3_TX
    PB11     ------> USART3_RX 
    */
    HAL_GPIO_DeInit(GPIOB, GPIO_PIN_10|GPIO_PIN_11);

    /* USART3 interrupt Deinit */
    HAL_NVIC_DisableIRQ(USART3_IRQn);
  /* USER CODE BEGIN USART3_MspDeInit 1 */

  /* USER CODE END USART3_MspDeInit 1 */
  }
} 

/* USER CODE BEGIN 1 */
void StartUART_Rx(UART_HandleTypeDef *uartHandle)
{
	if(uartHandle->Instance==USART1)
	{
		HAL_UART_Receive_IT(uartHandle,&a,1);		
	}
	else if(uartHandle->Instance==USART2)
	{
		HAL_UART_Receive_IT(uartHandle,&b,1);
	}
	else if(uartHandle->Instance==USART3)
	{
		HAL_UART_Receive_IT(uartHandle,&c,1);
	}
}

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *uartHandle)
{	
	if(uartHandle->Instance==USART1)
	{
		if(UART1_Callback!=NULL)
		{
			UART1_Callback(a);
		}
		HAL_UART_Receive_IT(uartHandle,&a,1);					
	}
	else if(uartHandle->Instance==USART2)
	{
		if(UART2_Callback!=NULL)
		{
			UART2_Callback(b);
		}
		HAL_UART_Receive_IT(uartHandle,&b,1);
	}
	else if(uartHandle->Instance==USART3)
	{
		if(UART3_Callback!=NULL)
		{
			UART3_Callback(c);
		}
		HAL_UART_Receive_IT(uartHandle,&c,1);
	}
}
void HAL_UART_ErrorCallback(UART_HandleTypeDef *huart)
{
	if(huart->RxState==HAL_UART_STATE_BUSY_RX)
	{
      huart->RxState = HAL_UART_STATE_READY;
	}
	
	if(huart->Instance==USART1)
	{
		a = (uint16_t)(huart->Instance->DR & (uint16_t)0x00FF);
		HAL_UART_Receive_IT(huart,&a,1);
	}
	else if(huart->Instance==USART2)
	{
		b = (uint16_t)(huart->Instance->DR & (uint16_t)0x00FF);
		HAL_UART_Receive_IT(huart,&b,1);
	}
	else if(huart->Instance==USART3)
	{
		c = (uint16_t)(huart->Instance->DR & (uint16_t)0x00FF);
		HAL_UART_Receive_IT(huart,&c,1);
	}
}
/* USER CODE END 1 */

/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/