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基于STM32HAL库(窗口看门狗)-简述

news 来源：原创 2024/5/13 3:36:42

概述

一、开发环境

二、STM32CubeMx配置

三、编码

四、运行结果

五、总结

概述

一个成熟靠谱的项目，离不开“看门狗”的必选项，凡是人写的程序多少都会有出现bug的情况（或芯片外设受外界干扰导致故障程序卡死、跑飞的情况）。为了避免产品变成砖头，引入看门狗是很有必要，可以有效解决程序的跑飞（确保程序在大部分情况能正常运行）。

来自百度百科解释（看门狗）
看门狗定时器（WDT，Watch Dog Timer）是单片机的一个组成部分，它实际上是一个计数器，一般给看门狗一个数字，程序开始运行后看门狗开始计数。如果程序运行正常，过一段时间CPU应发出指令让看门狗置零，重新开始计数。如果看门狗增加到设定值就认为程序没有正常工作，强制整个系统复位。

STM32的内置看门狗-(详细请移步参阅-STM32F4xx中文参考手册.pdf文档)

STM32内置两个看门狗，提供了更高的安全性、时间的精确性和使用的灵活性。两个看门狗设备（独立看门狗、窗口看门狗）可以用来检测和解决由软件错误引起的故障。当计数器达到给定的超时值时，触发一个中断（仅适用窗口看门狗）或者产生系统复位。

1）、独立看门狗（IWDG)由专用的低速时钟（LSI）驱动（32kHz），即使主时钟发生故障它仍有效。独立看门狗适合应用于需要看门狗作为一个在主程序之外能够完全独立工作，并且对时间精度要求低的场合。
2）、窗口看门狗由从APB1时钟（84MHz）分频后得到时钟驱动（42MHz）。通过可配置的时间窗口来检测应用程序非正常的过迟或过早操作。窗口看门狗最适合那些要求看门狗在精确计时窗口起作用的程序。

一、开发环境

1、硬件平台
STM32F401CEU6
内部Flash : 512Kbytes，SARM : 96 Kbytes

二、STM32CubeMx配置

2.1、系统时钟配置

2.2、下载调试配置

2.3、TIM配置（1ms中断）

2.4、usart1配置

2.5、窗口看门狗（WWDG）

窗口看门狗的定义
窗口看门狗跟独立看门狗一样，也是一个递减计数器不断的往下递减计数，当减到一个固定值 0x3F 时还不喂狗的话，产生复位，这个值叫窗口的下限，是固定的值，不能改变。

窗口看门狗之所以称为窗口，就是因为其喂狗时间是在一个有上下限的范围内（计数器减到某个值~计数器减到0x3F），在这个范围内才可以喂狗，可以通过设定相关寄存器，设定其上限时间（但是下限是固定的0x3F）。

1）、计数器的初始值
2）、是我们设置的上窗口（W[6:0]值）
3）、是下窗口值(0x3F)
窗口看门狗计数器的值只有在2和3 之间(上窗口和下窗口之间)才可以喂狗。

窗口看门狗中断：

并且窗口看门狗还可以使能中断，如果使能了提前唤醒中断，系统出现问题，喂狗函数没有生效，那么在计数器由减到0x40 (0x3f+1) 的时候，便会先进入中断，之后才会复位，你也可以在中断里面喂狗。

A、第一种计算方法：

从上图得知
看门狗超时时间：Twwdg = Tpclk1 x 4096 x 2^wdgtb x (T[5:0]+ 1) ms；
当PCLK1 = 42MHZ 时，WDGTB 取不同的值时有最小和最大的超时时间；
当WDGTB=0时，递减计数器有7 位T[6:0] ，当位6 变为0 的时候就会产生复位，实际上有效的计数位是T[5:0]，而且T6 必须先设置为1。如果T[5:0]=0 时，递减计数器再减一次，就产生复位了，那这减一的时间就等于计数器的周期=1/CNT_CK = Tpclk1 * 4096 * (2 ^WDGTB) = 1/42 * 4096 *2^ 0 = 97.52us，这个就是最短的超时时间。

如果T[5:0] 全部装满为1，即63，当他减到0X40 变成0X3F 时，所需的时间就是最大的超时时间 = 97.52 *(2^6) = 6.241ms。

B、第二种计算方法：

看门狗超时时间：Twwdg = ( 4096 * 窗口值 ) / PCLK1，
当PCLK1 = 42MHZ 时，WDGTB 取不同的值时有最小和最大的超时时间；
计数器最大值取127，窗口下限值为63，
最小超时时间：窗口上限值为64，窗口值为1
最大超时时间：窗口上限值为127，窗口值为64
当WDGTB=0时，分频系数为1，（STM32Cube MX可以直接配置分频系数）
最小超时时间=1/CNT_CK = (( 4096 * 分频系数 ) / PCLK1) * 窗口值 = 1/42 * 4096 * 1 = 97.52us；
最大的超时时间=1/CNT_CK = (( 4096 * 分频系数 ) / PCLK1) * 窗口值= 1/42 * 4096 * 64 = 97.52 * 64 = 6.241ms。

当我们配置WWDG如下时：
        1）、配置分频系数为8，
        2）、窗口上限值为90，
        3）、窗口下限值为63=(0x3F)，
        4）、计数器的值为127，
        5）、窗口值为27，(90+(63+1) - 127 = 154 - 127 = 27)
        6）、PCLK1 = 42MHz，
窗口时间 = ((4096分频系数)/PCLK1) * 27 = ((4096 * 8) / 42MHz) * 27 = 21.065 ms
最早喂狗时间 = ((4096分频系数)/PCLK1) * (127 - 90) = ((4096 * 8) / 42MHz) * 37 = 28.867 ms
最迟喂狗时间 = ((4096*分频系数)/PCLK1) * (127 - 63) = ((4096 * 8) / 42MHz) * 64 = 49.932 ms

2.6、生成代码

三、编码

1、usart.c

/* USER CODE BEGIN Header */
/********************************************************************************* @file    usart.c* @brief   This file provides code for the configuration*          of the USART instances.******************************************************************************* @attention** Copyright (c) 2023 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 *//* 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 *//* 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_PIN_10;GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;GPIO_InitStruct.Pull = GPIO_NOPULL;GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;GPIO_InitStruct.Alternate = GPIO_AF7_USART1;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 */
#include "stdio.h"
#ifdef __GNUC__/* With GCC/RAISONANCE, small printf (option LD Linker->Libraries->Small printfset to 'Yes') calls __io_putchar() */#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#else#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#endif /* __GNUC__ */
/*** @brief  Retargets the C library printf function to the USART.* @param  None* @retval None*/
PUTCHAR_PROTOTYPE
{/* Place your implementation of fputc here *//* e.g. write a character to the EVAL_COM1 and Loop until the end of transmission */HAL_UART_Transmit(&huart1, (uint8_t *)&ch, 1, 0xFFFF);return ch;
}int fgetc(FILE * f)
{uint8_t ch = 0;HAL_UART_Receive(&huart1, (uint8_t *)&ch, 1, 0xffff);return ch;
}/* USER CODE END 1 */

2、 tim.c文件 (本示例使用“定时器”模拟任务来执行程序逻辑代码)

/* USER CODE BEGIN Header */
/********************************************************************************* @file    tim.c* @brief   This file provides code for the configuration*          of the TIM instances.******************************************************************************* @attention** Copyright (c) 2023 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 "tim.h"/* USER CODE BEGIN 0 *//* USER CODE END 0 */TIM_HandleTypeDef htim1;/* TIM1 init function */
void MX_TIM1_Init(void)
{/* USER CODE BEGIN TIM1_Init 0 *//* USER CODE END TIM1_Init 0 */TIM_ClockConfigTypeDef sClockSourceConfig = {0};TIM_MasterConfigTypeDef sMasterConfig = {0};/* USER CODE BEGIN TIM1_Init 1 *//* USER CODE END TIM1_Init 1 */htim1.Instance = TIM1;htim1.Init.Prescaler = 84-1;htim1.Init.CounterMode = TIM_COUNTERMODE_UP;htim1.Init.Period = 1000-1;htim1.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;htim1.Init.RepetitionCounter = 0;htim1.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;if (HAL_TIM_Base_Init(&htim1) != HAL_OK){Error_Handler();}sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;if (HAL_TIM_ConfigClockSource(&htim1, &sClockSourceConfig) != HAL_OK){Error_Handler();}sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;if (HAL_TIMEx_MasterConfigSynchronization(&htim1, &sMasterConfig) != HAL_OK){Error_Handler();}/* USER CODE BEGIN TIM1_Init 2 *//* USER CODE END TIM1_Init 2 */}void HAL_TIM_Base_MspInit(TIM_HandleTypeDef* tim_baseHandle)
{if(tim_baseHandle->Instance==TIM1){/* USER CODE BEGIN TIM1_MspInit 0 *//* USER CODE END TIM1_MspInit 0 *//* TIM1 clock enable */__HAL_RCC_TIM1_CLK_ENABLE();/* TIM1 interrupt Init */HAL_NVIC_SetPriority(TIM1_UP_TIM10_IRQn, 0, 0);HAL_NVIC_EnableIRQ(TIM1_UP_TIM10_IRQn);/* USER CODE BEGIN TIM1_MspInit 1 *//* USER CODE END TIM1_MspInit 1 */}
}void HAL_TIM_Base_MspDeInit(TIM_HandleTypeDef* tim_baseHandle)
{if(tim_baseHandle->Instance==TIM1){/* USER CODE BEGIN TIM1_MspDeInit 0 *//* USER CODE END TIM1_MspDeInit 0 *//* Peripheral clock disable */__HAL_RCC_TIM1_CLK_DISABLE();/* TIM1 interrupt Deinit */HAL_NVIC_DisableIRQ(TIM1_UP_TIM10_IRQn);/* USER CODE BEGIN TIM1_MspDeInit 1 *//* USER CODE END TIM1_MspDeInit 1 */}
}/* USER CODE BEGIN 1 */
#include "stdio.h"
#include "wwdg.h"
uint32_t timeCount_10ms = 0;
uint32_t timeCount_20ms = 0;
uint8_t times = 0;
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim){if(htim->Instance == TIM1) {	//任务计数1mstimeCount_10ms++;timeCount_20ms++;if(timeCount_10ms==10) {timeCount_10ms = 0;printf("time + 10ms\n");//通过得知早喂晚喂狗都不行,一定要在上窗口和下窗口之间喂狗才行//最早喂狗时间 = ((4096分频系数)/PCLK1) * (127 - 90) = ((4096 * 8) / 42MHz) * 37 = 28.867 ms//最迟喂狗时间 = ((4096*分频系数)/PCLK1) * (127 - 63) = ((4096 * 8) / 42MHz) * 64 = 49.932 mstimes++;if (times == 3) {printf("喂狗成功 \n");HAL_WWDG_Refresh(&hwwdg);      //喂狗} else if (times == 5) {times = 0;printf("超时喂狗!!! \n");}}}
}/* USER CODE END 1 */

3、wwdg.c文件
HAL库对应的API

HAL_WWDG_Init(WWDG_HandleTypeDef *hwwdg); 	//看门狗初始化
HAL_WWDG_Refresh(WWDG_HandleTypeDef *hwwdg);	//喂狗
HAL_WWDG_IRQHandler(WWDG_HandleTypeDef *hwwdg);		//看门狗中断处理函数//功能：  判断中断是否正常，并进入中断回调函数
__weak HAL_WWDG_EarlyWakeupCallback(hwwdg);		//看门狗中断回调函数

/* USER CODE BEGIN Header */
/********************************************************************************* @file    wwdg.c* @brief   This file provides code for the configuration*          of the WWDG instances.******************************************************************************* @attention** Copyright (c) 2023 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 "wwdg.h"/* USER CODE BEGIN 0 *//* USER CODE END 0 */WWDG_HandleTypeDef hwwdg;/* WWDG init function */
void MX_WWDG_Init(void)
{/* USER CODE BEGIN WWDG_Init 0 *//* USER CODE END WWDG_Init 0 *//* USER CODE BEGIN WWDG_Init 1 *//* USER CODE END WWDG_Init 1 */hwwdg.Instance = WWDG;hwwdg.Init.Prescaler = WWDG_PRESCALER_8;hwwdg.Init.Window = 95;hwwdg.Init.Counter = 127;hwwdg.Init.EWIMode = WWDG_EWI_ENABLE;if (HAL_WWDG_Init(&hwwdg) != HAL_OK){Error_Handler();}/* USER CODE BEGIN WWDG_Init 2 *//* USER CODE END WWDG_Init 2 */}void HAL_WWDG_MspInit(WWDG_HandleTypeDef* wwdgHandle)
{if(wwdgHandle->Instance==WWDG){/* USER CODE BEGIN WWDG_MspInit 0 *//* USER CODE END WWDG_MspInit 0 *//* WWDG clock enable */__HAL_RCC_WWDG_CLK_ENABLE();/* WWDG interrupt Init */HAL_NVIC_SetPriority(WWDG_IRQn, 0, 0);HAL_NVIC_EnableIRQ(WWDG_IRQn);/* USER CODE BEGIN WWDG_MspInit 1 *//* USER CODE END WWDG_MspInit 1 */}
}/* USER CODE BEGIN 1 */
#include "stdio.h"void HAL_WWDG_EarlyWakeupCallback(WWDG_HandleTypeDef *hwwdg)
{/* Prevent unused argument(s) compilation warning */UNUSED(hwwdg);printf("callback 超时喂狗 \r\n");	
}
/* USER CODE END 1 */

4、main.c文件

/* USER CODE BEGIN Header */
/********************************************************************************* @file           : main.c* @brief          : Main program body******************************************************************************* @attention** Copyright (c) 2023 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 "tim.h"
#include "usart.h"
#include "wwdg.h"
#include "gpio.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "stdio.h"
/* 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 *//* 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();MX_TIM1_Init();MX_WWDG_Init();/* USER CODE BEGIN 2 */HAL_TIM_Base_Start_IT(&htim1);printf("heihei wwdg \r\n");/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){/* 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};/** Configure the main internal regulator output voltage*/__HAL_RCC_PWR_CLK_ENABLE();__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE2);/** 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.PLL.PLLState = RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;RCC_OscInitStruct.PLL.PLLM = 25;RCC_OscInitStruct.PLL.PLLN = 168;RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;RCC_OscInitStruct.PLL.PLLQ = 4;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 */