1.打开STM32CubeMX选择好对应的芯片，打开IWDG

 2.打开串口1进行调试

 3.配置好时钟

 4.写好项目名称，选好开发环境，最后获取代码。 

5.打开工程，点击魔术棒，勾选Use Micro LIB

 6.修改main.c

#include "main.h"
#include "iwdg.h"
#include "usart.h"
#include "gpio.h"
#include <stdio.h>
#include <stm32_hal_legacy.h>void SystemClock_Config(void);extern	IWDG_HandleTypeDef hiwdg;void PWR_Enter_Standby(void)
{__HAL_RCC_PWR_CLK_ENABLE();if (__HAL_PWR_GET_FLAG(PWR_FLAG_SB) != RESET){__HAL_PWR_CLEAR_FLAG(PWR_FLAG_SB);if (__HAL_PWR_GET_FLAG(PWR_FLAG_WUF2) != RESET){__HAL_PWR_CLEAR_FLAG(PWR_FLAG_WUF2);}if (__HAL_PWR_GET_FLAG(PWR_FLAG_WUF4) != RESET){__HAL_PWR_CLEAR_FLAG(PWR_FLAG_WUF4);}}HAL_PWR_EnableWakeUpPin(PWR_WAKEUP_PIN2_HIGH);__HAL_PWR_CLEAR_FLAG(PWR_FLAG_WUF2);//HAL_PWR_EnableWakeUpPin(PWR_WAKEUP_PIN4_HIGH);HAL_PWR_EnterSTANDBYMode();
}void IWDG_OBProgram(void)
{/* 配置用户选项字节：在停止模式下冻结独立看门狗计数器 */FLASH_OBProgramInitTypeDef obprogram_init;/* 读取用户选项字节 */HAL_FLASHEx_OBGetConfig(&obprogram_init);printf("SYS USERConfig = 0x%x\r\n", obprogram_init.USERConfig);/* 判断FLASH_OPTR寄存器的IWDG_STDBY位是否置位（不判断也行） */if(obprogram_init.USERConfig & FLASH_OPTR_IWDG_STDBY){/* 置位则清零IWDG_STOP位 */obprogram_init.OptionType = OPTIONBYTE_USER;obprogram_init.USERType = OB_USER_IWDG_STDBY;obprogram_init.USERConfig = OB_IWDG_STDBY_FREEZE; obprogram_init.RDPLevel = OB_RDP_LEVEL_0;		/* 以下流程是根据手册上提供的 */HAL_FLASH_Unlock();HAL_FLASH_OB_Unlock();HAL_FLASHEx_OBProgram(&obprogram_init);HAL_FLASH_OB_Lock();HAL_FLASH_Lock();/* OBL_LAUNCH：选项字节重载位，用来生效上述更改(如果OPTLOCK为0，将此位置1，则会导致复位，如果 OPTLOCK为1，则此位无法写入,MCU复位后此位默认置1) */HAL_FLASH_OB_Launch();HAL_FLASHEx_OBGetConfig(&obprogram_init);printf("SET USERConfig = 0x%x\r\n", obprogram_init.USERConfig);}
}int main(void)
{HAL_Init();SystemClock_Config();HAL_Delay(1000);MX_GPIO_Init();MX_USART1_UART_Init();/* USER CODE BEGIN 2 */MX_IWDG_Init();IWDG_OBProgram();printf("code init \r\n");while (1){/* USER CODE END WHILE */HAL_IWDG_Refresh(&hiwdg); //HAL_Delay(500);printf("PWR_Enter_Standby\r\n");PWR_Enter_Standby();printf("code start\r\n");/* 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_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);/** Initializes the RCC Oscillators according to the specified parameters* in the RCC_OscInitTypeDef structure.*/RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI|RCC_OSCILLATORTYPE_LSI;RCC_OscInitStruct.HSIState = RCC_HSI_ON;RCC_OscInitStruct.HSIDiv = RCC_HSI_DIV1;RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;RCC_OscInitStruct.LSIState = RCC_LSI_ON;RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV1;RCC_OscInitStruct.PLL.PLLN = 8;RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;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_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;RCC_ClkInitStruct.APB1CLKDivider = 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 */

7.串口打印，修改了OB_USER_IWDG_STDBY，系统看门狗复位一次后就没有再复位了。

 源码链接：跳转链接