实验原理：

　　通过STM32的三个GPIO口驱动三色LED的三个通道，设定GPIO为推挽输出，采用

灌电流的方式与LED连接，输出高电平LED灭，输出低电平LED亮，通过系统定时器实现

1s定时，每秒变换一次LED颜色。

核心代码：

int main(void){  /* USER CODE BEGIN 1 */    static int work_status = 0;  /* USER CODE END 1 */  /* MCU Configuration----------------------------------------------------------*/  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */  HAL_Init();                        //³õʼ»¯ËùÓÐÍâÉè  /* 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();             //GPIO ³õʼ»¯  /* USER CODE BEGIN 2 */  /* USER CODE END 2 */  /* Infinite loop */  /* USER CODE BEGIN WHILE */  while (1)  {    //ÿ¸ôÒ»ÃëÈýÉ«µÆ½øÐн»ÌæÑ­»·ÉÁ˸  /* USER CODE END WHILE */  /* USER CODE BEGIN 3 */                if(systick.second_flag == 1){            systick.second_flag = 0;            work_status += 1;            if(work_status > 2)work_status = 0;        }        switch (work_status){            case 0 :                LED_RED_ON;                LED_GREEN_OFF;                LED_BLUE_OFF;                break;                            case 1 :                LED_RED_OFF;                LED_GREEN_ON;                LED_BLUE_OFF;                break;                            case 2:                LED_RED_OFF;                LED_GREEN_OFF;                LED_BLUE_ON;                break;                            default:                                break;            }  }  /* USER CODE END 3 */}

void HAL_SYSTICK_Callback(void){    static int counter = 0;        if((counter ++ % 1000) == 0){        systick.second_flag = 1;    }}

源代码下载链接：

链接： 密码：70sj