一、适用场景适用场景大电流/交流负载开关家电、灯光、风扇、隔离控制MCU 驱动高电压电路、定时/远程开关、自动化设备控制、样机/实验中的电源切换、继电器矩阵与驱动练习。二、器材清单继电器模块×1STM32 开发板3.3V MCU×1稳定电源5V/3.3V(最好是5v)三、工作原理要点继电器是电磁机械开关线圈通电产生磁场吸合触点实现触点的闭合/断开常开 NO / 常闭 NC / 公用 COM。驱动需求线圈电流通常较大几十 mA 到数百 mA不能直接由 MCU IO 驱动需晶体管 / 驱动阵列 / 模块自带驱动与反向吸收二极管flyback来保护 MCU。机械特性有机械响应延迟吸合/释放几十 ms寿命受负载和开关冲击影响直流开关会有弧光加速触点损耗需要吸收措施。四、接线示意DC-→GNDDC→5V/3.3V电源标准库IO→PA3HAL库IO→PA9(注意驱动io口不能被分压如c8t6模块的PC13被连上LED且为开漏输出驱动电压严重不足)五、示例代码标准库#include stm32f10x.h #include stdio.h #include bsp_SysTick.h #include bsp_usart.h void gpio_init() { GPIO_InitTypeDef PA; //使能时钟 RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE); PA.GPIO_Pin GPIO_Pin_3; PA.GPIO_Mode GPIO_Mode_Out_PP; PA.GPIO_Speed GPIO_Speed_50MHz; GPIO_Init(GPIOA,PA); } int main(void) { SysTick_Init(); //延时函数初始化 gpio_init(); //初始化与LED连接的硬件接口 USART_Config(); while(1) { GPIO_ResetBits(GPIOA,GPIO_Pin_3); Usart_SendString(USART1,open\n); Delay_us(1000000); GPIO_SetBits(GPIOA,GPIO_Pin_3); Usart_SendString(USART1,close\n); Delay_us(2000000); } }HAL库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(); /* USER CODE BEGIN 2 */ /* USER CODE END 2 */ /* Infinite loop */ /* USER CODE BEGIN WHILE */ while (1) { HAL_GPIO_WritePin(GPIOA,GPIO_PIN_9,GPIO_PIN_RESET); HAL_Delay(1000); HAL_GPIO_WritePin(GPIOA,GPIO_PIN_9,GPIO_PIN_SET); HAL_Delay(1000); /* USER CODE END WHILE */ /* USER CODE BEGIN 3 */ } /* USER CODE END 3 */ }六、讲解视频https://www.bilibili.com/video/BV1gVr9BBEMM/?spm_id_from333.1387.search.video_card.clickvd_sourcef7dfe1b14f260b9cc3a146d2dbfd0719https://www.bilibili.com/video/BV1hGr9BuEth/?spm_id_from333.1387.search.video_card.clickvd_sourcef7dfe1b14f260b9cc3a146d2dbfd0719https://www.bilibili.com/video/BV18Gr9BuEr7/?spm_id_from333.1387.search.video_card.clickvd_sourcef7dfe1b14f260b9cc3a146d2dbfd0719