STM32F103单片机HAL库串口通信卡死问题解决方法

在上篇文章 STM32F103单片机使用STM32CubeMX创建IAR串口工程 中分享了使用cubeMX直接生成串口代码的方法，在测试的过程中无意间发现，串口会出现卡死的问题。

当串口一次性发送十几个数据的时候，串口感觉像卡死了一样，不再接收数据。通过对串口的监控可以看到，串口中ErrorCode的值变成了8。这时候只有对单片机断电重启，串口才能恢复。
在网上查资料发现造成这个原因主要是HAL的流程问题，当串口在发送数据的时候，如果又接收到了数据，程序中就会出现死锁的情况。
找了好多方法，都没有解决这个问题。大多数的方法是自己编写一个错误码回调函数，当出现错误的时候，在错误码回调函数中清除这个错误码计数值。

// 错误回调函数
void HAL_UART_ErrorCallback(UART_HandleTypeDef *huart)
{if (huart == &huart1){if (__HAL_UART_GET_FLAG(huart, UART_FLAG_ORE) != RESET){__HAL_UART_CLEAR_OREFLAG(huart);HAL_UART_Receive_IT(&huart1, &rx_buf, 1);     }}
}
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{if (huart->Instance == USART1){HAL_UART_Transmit(&huart1, &rx_buf, 1, 1000);   HAL_UART_Receive_IT(&huart1, &rx_buf, 1); }
}

通过上图中可以看出，接收的数据没有卡死，ErrorCode的值也一直是0，但是接收的数据总是少一个。也是没有彻底解决问题。

然后使用正点原子的串口例程测试的时候没出现串口卡死的情况，也没出现丢数据的情况。所以就将正点原子的串口接收方法移植过来。
为了方便分析这里直接贴代码。
usart.c

/* USER CODE BEGIN Header */
/********************************************************************************* @file    usart.c* @brief   This file provides code for the configuration*          of the USART instances.******************************************************************************* @attention** Copyright (c) 2024 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "usart.h"/* USER CODE BEGIN 0 *//* 接收缓冲, 最大USART_REC_LEN个字节. */
uint8_t g_usart_rx_buf[USART_REC_LEN];/*  接收状态*  bit15，      接收完成标志*  bit14，      接收到0x0d*  bit13~0，    接收到的有效字节数目
*/
uint16_t g_usart_rx_sta = 0;uint8_t g_rx_buffer[RXBUFFERSIZE]; 
/* USER CODE END 0 */UART_HandleTypeDef huart1;/* USART1 init function */void MX_USART1_UART_Init(void)
{/* USER CODE BEGIN USART1_Init 0 *//* USER CODE END USART1_Init 0 *//* USER CODE BEGIN USART1_Init 1 *//* USER CODE END USART1_Init 1 */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();}/* USER CODE BEGIN USART1_Init 2 */  HAL_UART_Receive_IT(&huart1, (uint8_t *)g_rx_buffer, RXBUFFERSIZE);  /* USER CODE END USART1_Init 2 */}void HAL_UART_MspInit(UART_HandleTypeDef* uartHandle)
{GPIO_InitTypeDef GPIO_InitStruct = {0};if(uartHandle->Instance==USART1){/* USER CODE BEGIN USART1_MspInit 0 *//* USER CODE END USART1_MspInit 0 *//* USART1 clock enable */__HAL_RCC_USART1_CLK_ENABLE();__HAL_RCC_GPIOA_CLK_ENABLE();/**USART1 GPIO ConfigurationPA9     ------> USART1_TXPA10     ------> 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, 0, 0);HAL_NVIC_EnableIRQ(USART1_IRQn);/* USER CODE BEGIN USART1_MspInit 1 *//* USER CODE END USART1_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 ConfigurationPA9     ------> USART1_TXPA10     ------> 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 */}
}/* USER CODE BEGIN 1 *///IAR 中重定向函数要使用putchar函数才行
int putchar(int ch)
{
HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,1000);
return ch;
}void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{if (huart->Instance == USART1){if ((g_usart_rx_sta & 0x8000) == 0)             /* 接收未完成 */{if (g_usart_rx_sta & 0x4000)                /* 接收到了0x0d（即回车键） */{if (g_rx_buffer[0] != 0x0a)             /* 接收到的不是0x0a（即不是换行键） */{g_usart_rx_sta = 0;                 /* 接收错误,重新开始 */}else                                    /* 接收到的是0x0a（即换行键） */{g_usart_rx_sta |= 0x8000;           /* 接收完成了 */}}else                                        /* 还没收到0X0d（即回车键） */{if (g_rx_buffer[0] == 0x0d)g_usart_rx_sta |= 0x4000;else{g_usart_rx_buf[g_usart_rx_sta & 0X3FFF] = g_rx_buffer[0];g_usart_rx_sta++;if (g_usart_rx_sta > (USART_REC_LEN - 1)){g_usart_rx_sta = 0;             /* 接收数据错误,重新开始接收 */}}}}HAL_UART_Receive_IT(&huart1, (uint8_t *)g_rx_buffer, RXBUFFERSIZE);}}/* USER CODE END 1 */

usart.h

/* USER CODE BEGIN Header */
/********************************************************************************* @file    usart.h* @brief   This file contains all the function prototypes for*          the usart.c file******************************************************************************* @attention** Copyright (c) 2024 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Define to prevent recursive inclusion -------------------------------------*/
#ifndef __USART_H__
#define __USART_H__#ifdef __cplusplus
extern "C" {
#endif/* Includes ------------------------------------------------------------------*/
#include "main.h"/* USER CODE BEGIN Includes */
#include "stdio.h"
/* USER CODE END Includes */extern UART_HandleTypeDef huart1;/* USER CODE BEGIN Private defines */#define USART_REC_LEN               200         /* 定义最大接收字节数 200 */
#define USART_EN_RX                 1           /* 使能（1）/禁止（0）串口1接收 */
#define RXBUFFERSIZE   1                        /* 缓存大小 */extern uint8_t  g_usart_rx_buf[USART_REC_LEN];  /* 接收缓冲,最大USART_REC_LEN个字节.末字节为换行符 */
extern uint16_t g_usart_rx_sta;                 /* 接收状态标记 */
extern uint8_t g_rx_buffer[RXBUFFERSIZE];       /* HAL库USART接收Buffer *//* USER CODE END Private defines */void MX_USART1_UART_Init(void);/* USER CODE BEGIN Prototypes *//* USER CODE END Prototypes */#ifdef __cplusplus
}
#endif#endif /* __USART_H__ */

main.c

/* USER CODE BEGIN Header */
/********************************************************************************* @file           : main.c* @brief          : Main program body******************************************************************************* @attention** Copyright (c) 2024 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usart.h"
#include "gpio.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes *//* USER CODE END Includes *//* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD *//* USER CODE END PTD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD *//* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM *//* USER CODE END PM *//* Private variables ---------------------------------------------------------*//* USER CODE BEGIN PV *//* USER CODE END PV *//* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP *//* USER CODE END PFP *//* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 *//* USER CODE END 0 *//*** @brief  The application entry point.* @retval int*/
int main(void)
{/* USER CODE BEGIN 1 */uint8_t len;/* USER CODE END 1 *//* MCU Configuration--------------------------------------------------------*//* Reset of all peripherals, Initializes the Flash interface and the Systick. */HAL_Init();/* USER CODE BEGIN Init *//* USER CODE END Init *//* Configure the system clock */SystemClock_Config();/* USER CODE BEGIN SysInit *//* USER CODE END SysInit *//* Initialize all configured peripherals */MX_GPIO_Init();MX_USART1_UART_Init();/* USER CODE BEGIN 2 *//* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){if (g_usart_rx_sta & 0x8000)        /* 接收到了数据? */{len = g_usart_rx_sta & 0x3fff;  /* 得到此次接收到的数据长度 */printf("\r\n");HAL_UART_Transmit(&huart1, (uint8_t*)g_usart_rx_buf, len, 1000);     /* 发送接收到的数据 */while(__HAL_UART_GET_FLAG(&huart1, UART_FLAG_TC) != SET);           /* 等待发送结束 */g_usart_rx_sta = 0;}/* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */
}/*** @brief System Clock Configuration* @retval None*/
void SystemClock_Config(void)
{RCC_OscInitTypeDef RCC_OscInitStruct = {0};RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};/** Initializes the RCC Oscillators according to the specified parameters* in the RCC_OscInitTypeDef structure.*/RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;RCC_OscInitStruct.HSEState = RCC_HSE_ON;RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;RCC_OscInitStruct.HSIState = RCC_HSI_ON;RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK){Error_Handler();}/** Initializes the CPU, AHB and APB buses clocks*/RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK){Error_Handler();}
}/* USER CODE BEGIN 4 *//* USER CODE END 4 *//*** @brief  This function is executed in case of error occurrence.* @retval None*/
void Error_Handler(void)
{/* USER CODE BEGIN Error_Handler_Debug *//* User can add his own implementation to report the HAL error return state */__disable_irq();while (1){}/* USER CODE END Error_Handler_Debug */
}#ifdef  USE_FULL_ASSERT
/*** @brief  Reports the name of the source file and the source line number*         where the assert_param error has occurred.* @param  file: pointer to the source file name* @param  line: assert_param error line source number* @retval None*/
void assert_failed(uint8_t *file, uint32_t line)
{/* USER CODE BEGIN 6 *//* User can add his own implementation to report the file name and line number,ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) *//* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

在接收回调函数中接收到数据之后先存放到数组之中，当收到回车换行符之后结束接收，然后在main函数中检测接收标志位，如果接收完成，再将接收的数据打印出来。这个代码中没添加错误回调函数，唯一改变的就是串口接收和发送的方式。
在这里要注意一个问题，就是printf()函数重映射的问题。由于使用的是IAR编译器，所以串口重映射的代码和Keil编译器中不一样。
IAR中使用的printf()重映射代码为

int putchar(int ch)
{
HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,1000);
return ch;
}

如果是keil编译器的话，printf()重映射代码为

int fputc(int ch, FILE *f)
{HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,1000);return ch;
}

这两个唯一的区别就是函数名不一样，函数中的代码都是一样的。下载代码测试

可以看到发送一千多个字节，串口没有卡死，也没有数据丢失的情况。

所以分析造成串口卡死或者数据丢失的原因主要原因应该是直接在接收中断中直接发送数据，由于是接收一个字节，立即发送一个字节，如果每次发送几十个字节的时候，每两个字节之间的时间是很短的。而HAL库的嵌套调用都比较多，效率比较低下，接收数据和发送数据冲突了。如果使用标准库的话，同样接收一个数据在发送一个数据，不会出现这个情况。

下面再使用标准库函数测试，代码如下

#include "uart1.h"
#include <stdio.h>static void NVIC_Configuration( void )
{NVIC_InitTypeDef NVIC_InitStructure;NVIC_PriorityGroupConfig( NVIC_PriorityGroup_2 );		 				// 嵌套向量中断控制器组选择NVIC_InitStructure.NVIC_IRQChannel = UART1_IRQ;		 					// 配置USART为中断源NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;		// 抢断优先级NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;		  		//子优先级NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;	 						//使能中断NVIC_Init( &NVIC_InitStructure );														//初始化配置NVIC
}
static void USART_Config( void )
{GPIO_InitTypeDef GPIO_InitStructure;USART_InitTypeDef USART_InitStructure;UART1_GPIO_APBxClkCmd( UART1_GPIO_CLK, ENABLE );						// 打开串口GPIO的时钟UART1_APBxClkCmd( UART1_CLK, ENABLE );											// 打开串口外设的时钟GPIO_InitStructure.GPIO_Pin = UART1_TX_GPIO_PIN;						// 将USART Tx的GPIO配置为推挽复用模式GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init( UART1_TX_GPIO_PORT, &GPIO_InitStructure );GPIO_InitStructure.GPIO_Pin = UART1_RX_GPIO_PIN;						// 将USART Rx的GPIO配置为浮空输入模式GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;GPIO_Init( UART1_RX_GPIO_PORT, &GPIO_InitStructure );// 配置串口的工作参数USART_InitStructure.USART_BaudRate = UART1_BAUDRATE;														// 配置波特率USART_InitStructure.USART_WordLength = USART_WordLength_8b;											// 配置 针数据字长USART_InitStructure.USART_StopBits = USART_StopBits_1;													// 配置停止位USART_InitStructure.USART_Parity = USART_Parity_No ;														// 配置校验位USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;	// 配置硬件流控制USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;									// 配置工作模式，收发一起USART_Init( UART1, &USART_InitStructure );																			// 完成串口的初始化配置NVIC_Configuration();																				// 串口中断优先级配置USART_ITConfig( UART1, USART_IT_RXNE, ENABLE );						  // 使能串口接收中断USART_Cmd( UART1, ENABLE );	   														  // 使能串口
}void  uart1_init( void )
{USART_Config();
}void USART1_IRQHandler( void )
{u16 tem = 0;if( USART_GetITStatus( UART1, USART_IT_RXNE ) != RESET ){tem = USART_ReceiveData( UART1 );USART_SendData( UART1, tem );}}

#ifndef __UART1_H
#define __UART1_H
#include "sys.h"// 串口1-USART1
#define  UART1                    USART1
#define  UART1_CLK                RCC_APB2Periph_USART1
#define  UART1_APBxClkCmd         RCC_APB2PeriphClockCmd
#define  UART1_BAUDRATE           115200// USART GPIO 引脚宏定义
#define  UART1_GPIO_CLK           (RCC_APB2Periph_GPIOA)
#define  UART1_GPIO_APBxClkCmd    RCC_APB2PeriphClockCmd#define  UART1_TX_GPIO_PORT       GPIOA   
#define  UART1_TX_GPIO_PIN        GPIO_Pin_9
#define  UART1_RX_GPIO_PORT       GPIOA
#define  UART1_RX_GPIO_PIN        GPIO_Pin_10#define  UART1_IRQ                USART1_IRQn
#define  UART1_IRQHandler         USART1_IRQHandlervoid  uart1_init(void);#endif

测试结果如下

通过对比可以看出，应该是HAL库的处理机制和标准库处理机制不一样了，所以同样的写法，串口测试结果却不一样。