在上篇文章 STM32F103單片機使用STM32CubeMX創建IAR串口工程 中分享了使用cubeMX直接生成串口代碼的方法,在測試的過程中無意間發現,串口會出現卡死的問題。
當串口一次性發送十幾個數據的時候,串口感覺像卡死了一樣,不再接收數據。通過對串口的監控可以看到,串口中ErrorCode的值變成了8。這時候只有對單片機斷電重啟,串口才能恢復。
在網上查資料發現造成這個原因主要是HAL的流程問題,當串口在發送數據的時候,如果又接收到了數據,程序中就會出現死鎖的情況。
找了好多方法,都沒有解決這個問題。大多數的方法是自己編寫一個錯誤碼回調函數,當出現錯誤的時候,在錯誤碼回調函數中清除這個錯誤碼計數值。
// 錯誤回調函數
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); }
}
通過上圖中可以看出,接收的數據沒有卡死,ErrorCode的值也一直是0,但是接收的數據總是少一個。也是沒有徹底解決問題。
然后使用正點原子的串口例程測試的時候沒出現串口卡死的情況,也沒出現丟數據的情況。所以就將正點原子的串口接收方法移植過來。
為了方便分析這里直接貼代碼。
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 *//* 接收緩沖, 最大USART_REC_LEN個字節. */
uint8_t g_usart_rx_buf[USART_REC_LEN];/* 接收狀態* bit15, 接收完成標志* bit14, 接收到0x0d* bit13~0, 接收到的有效字節數目
*/
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 中重定向函數要使用putchar函數才行
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(即回車鍵) */{if (g_rx_buffer[0] != 0x0a) /* 接收到的不是0x0a(即不是換行鍵) */{g_usart_rx_sta = 0; /* 接收錯誤,重新開始 */}else /* 接收到的是0x0a(即換行鍵) */{g_usart_rx_sta |= 0x8000; /* 接收完成了 */}}else /* 還沒收到0X0d(即回車鍵) */{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; /* 接收數據錯誤,重新開始接收 */}}}}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 /* 定義最大接收字節數 200 */
#define USART_EN_RX 1 /* 使能(1)/禁止(0)串口1接收 */
#define RXBUFFERSIZE 1 /* 緩存大小 */extern uint8_t g_usart_rx_buf[USART_REC_LEN]; /* 接收緩沖,最大USART_REC_LEN個字節.末字節為換行符 */
extern uint16_t g_usart_rx_sta; /* 接收狀態標記 */
extern uint8_t g_rx_buffer[RXBUFFERSIZE]; /* HAL庫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) /* 接收到了數據? */{len = g_usart_rx_sta & 0x3fff; /* 得到此次接收到的數據長度 */printf("\r\n");HAL_UART_Transmit(&huart1, (uint8_t*)g_usart_rx_buf, len, 1000); /* 發送接收到的數據 */while(__HAL_UART_GET_FLAG(&huart1, UART_FLAG_TC) != SET); /* 等待發送結束 */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 */
在接收回調函數中接收到數據之后先存放到數組之中,當收到回車換行符之后結束接收,然后在main函數中檢測接收標志位,如果接收完成,再將接收的數據打印出來。這個代碼中沒添加錯誤回調函數,唯一改變的就是串口接收和發送的方式。
在這里要注意一個問題,就是printf()函數重映射的問題。由于使用的是IAR編譯器,所以串口重映射的代碼和Keil編譯器中不一樣。
IAR中使用的printf()重映射代碼為
int putchar(int ch)
{
HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,1000);
return ch;
}
如果是keil編譯器的話,printf()重映射代碼為
int fputc(int ch, FILE *f)
{HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,1000);return ch;
}
這兩個唯一的區別就是函數名不一樣,函數中的代碼都是一樣的。下載代碼測試
可以看到發送一千多個字節,串口沒有卡死,也沒有數據丟失的情況。
所以分析造成串口卡死或者數據丟失的原因主要原因應該是直接在接收中斷中直接發送數據,由于是接收一個字節,立即發送一個字節,如果每次發送幾十個字節的時候,每兩個字節之間的時間是很短的。而HAL庫的嵌套調用都比較多,效率比較低下,接收數據和發送數據沖突了。如果使用標準庫的話,同樣接收一個數據在發送一個數據,不會出現這個情況。
下面再使用標準庫函數測試,代碼如下
#include "uart1.h"
#include <stdio.h>static void NVIC_Configuration( void )
{NVIC_InitTypeDef NVIC_InitStructure;NVIC_PriorityGroupConfig( NVIC_PriorityGroup_2 ); // 嵌套向量中斷控制器組選擇NVIC_InitStructure.NVIC_IRQChannel = UART1_IRQ; // 配置USART為中斷源NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1; // 搶斷優先級NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1; //子優先級NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //使能中斷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 ); // 打開串口GPIO的時鐘UART1_APBxClkCmd( UART1_CLK, ENABLE ); // 打開串口外設的時鐘GPIO_InitStructure.GPIO_Pin = UART1_TX_GPIO_PIN; // 將USART Tx的GPIO配置為推挽復用模式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; // 將USART Rx的GPIO配置為浮空輸入模式GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;GPIO_Init( UART1_RX_GPIO_PORT, &GPIO_InitStructure );// 配置串口的工作參數USART_InitStructure.USART_BaudRate = UART1_BAUDRATE; // 配置波特率USART_InitStructure.USART_WordLength = USART_WordLength_8b; // 配置 針數據字長USART_InitStructure.USART_StopBits = USART_StopBits_1; // 配置停止位USART_InitStructure.USART_Parity = USART_Parity_No ; // 配置校驗位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,收發一起USART_Init( UART1, &USART_InitStructure ); // 完成串口的初始化配置NVIC_Configuration(); // 串口中斷優先級配置USART_ITConfig( UART1, USART_IT_RXNE, ENABLE ); // 使能串口接收中斷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 引腳宏定義
#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
測試結果如下
通過對比可以看出,應該是HAL庫的處理機制和標準庫處理機制不一樣了,所以同樣的寫法,串口測試結果卻不一樣。