stm32 中写led定时4秒循环
时间: 2023-06-17 15:05:29 浏览: 57
可以使用定时器来实现定时功能,以下是使用STM32CubeIDE在STM32F407上实现LED定时4秒循环的示例代码:
1. 首先,在CubeMX中配置GPIO以及定时器
- 配置LED引脚为输出模式,例如PC13
- 配置定时器TIM2的时钟源为APB1,预分频系数为84-1,计数器自动重装载,重装载值为4199999(实现1秒中断),开启定时器中断
2. 在main函数中初始化GPIO和定时器,并开启定时器
```c
#include "main.h"
#include "stm32f4xx_hal.h"
TIM_HandleTypeDef htim2;
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM2_Init(void);
int main(void)
{
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_TIM2_Init();
HAL_TIM_Base_Start_IT(&htim2);
while (1)
{
}
}
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
if(htim->Instance == TIM2)
{
HAL_GPIO_TogglePin(GPIOC, GPIO_PIN_13);
}
}
static void MX_TIM2_Init(void)
{
htim2.Instance = TIM2;
htim2.Init.Prescaler = 84-1;
htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
htim2.Init.Period = 4199999;
htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
HAL_TIM_Base_Init(&htim2);
HAL_TIM_Base_Start_IT(&htim2);
}
static void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
__HAL_RCC_GPIOC_CLK_ENABLE();
GPIO_InitStruct.Pin = GPIO_PIN_13;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
}
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
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 = 8;
RCC_OscInitStruct.PLL.PLLN = 336;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = 7;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
RCC_ClkInitStruct.ClockType = 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_DIV4;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
{
Error_Handler();
}
}
```
在以上代码中,HAL_TIM_PeriodElapsedCallback()函数中的代码将在每次定时器中断发生时执行,即每隔1秒翻转一次LED。同时,由于定时器的重载值为4199999,所以当定时器累加到这个值时,会自动重载计数器,从而实现了每隔4秒循环一次。