用HAL库改写江科大的stm32入门-6-3 PWM驱动LED呼吸灯

1. 接线图：

2. 

2 :实验目的：

利用pwm实现呼吸灯。

关键PWM定时器设置：

代码部分：

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_TIM2_Init();/* USER CODE BEGIN 2 */// start timer2 pwmHAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_1); // start pwm on channel 1 of timer 2/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){// for breath led, change duty cycle of pwm, from 0 to 100% and back to 0for (int i = 0; i < 500; i++){__HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_1, i);  // set duty cycle of pwmHAL_Delay(10);}//delay 500msHAL_Delay(200);for (int i = 500; i > 0; i--){__HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_1, i);  // set duty cycle of pwmHAL_Delay(10);}//delay 200msHAL_Delay(200);/* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */
}

1. ps:pwm说明：

输出比较、CNT、CRR的概念：

pwm概念：