本文展示了一个基于STM32F1和FreeRTOS的双LED控制程序。主要内容包括：
-
系统配置：使用HSI时钟源通过PLL倍频至64MHz，配置系统时钟和外设时钟
-
GPIO初始化：设置PA1-PA3为红色LED输出，PB0-PB2为绿色LED输出
-
FreeRTOS任务创建：
- TaskRedLED：以400ms周期切换红色LED组
- TaskGreenLED：以1000ms周期切换绿色LED组
-
辅助功能：
- 系统时钟配置
- 错误处理函数
- 数字转换工具函数
程序采用FreeRTOS实时操作系统管理两个独立LED控制任务，实现不同频率的LED闪烁效果，展示了基本的RTOS任务创建和调度方法。
main.c
cpp
/**
******************************************************************************
* File Name : main.c
* Description : Dual LED Toggle with FreeRTOS (native API)
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "stm32f1xx_hal.h"
#include "FreeRTOS.h"
#include "task.h"
/* Peripheral handles (required by other modules for linker resolution) */
DMA_HandleTypeDef hdma_spi1_tx;
DMA_HandleTypeDef hdma_usart1_tx;
SPI_HandleTypeDef hspi1;
UART_HandleTypeDef huart1;
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
void Error_Handler(void);
static void MX_GPIO_Init(void);
static void TaskRedLED(void *pvParameters);
static void TaskGreenLED(void *pvParameters);
int main(void)
{
/* MCU Configuration----------------------------------------------------------*/
HAL_Init();
/* Configure the system clock */
SystemClock_Config();
/* Initialize all configured peripherals */
MX_GPIO_Init();
/* Create the Red LED toggle task (PA1/PA2/PA3), period = 400ms */
xTaskCreate(TaskRedLED, "RedLED", configMINIMAL_STACK_SIZE, NULL,
tskIDLE_PRIORITY + 1, NULL);
/* Create the Green LED toggle task (PB0/PB1/PB2), period = 1000ms */
xTaskCreate(TaskGreenLED, "GreenLED", configMINIMAL_STACK_SIZE, NULL,
tskIDLE_PRIORITY + 1, NULL);
/* Start scheduler */
vTaskStartScheduler();
/* We should never get here as control is now taken by the scheduler */
while (1)
{
}
}
/** System Clock Configuration
* HSI -> PLL (x16) -> 64MHz SYSCLK, HCLK=32MHz, APB1=8MHz, APB2=16MHz
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = 16;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI_DIV2;
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL16;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK
| RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV2;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
{
Error_Handler();
}
HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq() / 1000);
HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
/* SysTick_IRQn interrupt configuration */
HAL_NVIC_SetPriority(SysTick_IRQn, 15, 0);
}
/** Configure GPIO pins for LED control
* PA1/PA2/PA3 -> Red LED (Output Push-Pull)
* PB0/PB1/PB2 -> Green LED (Output Push-Pull)
*/
static void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct;
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOA_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();
/* Configure PA1, PA2, PA3 as output push-pull for Red LED */
GPIO_InitStruct.Pin = GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/* Configure PB0, PB1, PB2 as output push-pull for Green LED */
GPIO_InitStruct.Pin = GPIO_PIN_0 | GPIO_PIN_1 | GPIO_PIN_2;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/* Set initial output level low (LEDs off) */
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3, GPIO_PIN_RESET);
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0 | GPIO_PIN_1 | GPIO_PIN_2, GPIO_PIN_RESET);
}
/* TaskRedLED: Toggle Red LED on PA1/PA2/PA3, period = 400ms */
static void TaskRedLED(void *pvParameters)
{
for(;;)
{
HAL_GPIO_TogglePin(GPIOA, GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3);
vTaskDelay(pdMS_TO_TICKS(200));
}
}
/* TaskGreenLED: Toggle Green LED on PB0/PB1/PB2, period = 1000ms */
static void TaskGreenLED(void *pvParameters)
{
for(;;)
{
HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_0 | GPIO_PIN_1 | GPIO_PIN_2);
vTaskDelay(pdMS_TO_TICKS(500));
}
}
/* TIM1 Period Elapsed Callback - provides HAL time base */
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
if (htim->Instance == TIM1)
{
HAL_IncTick();
}
}
/* itoa: convert n to characters in s (required by SSD1306 module) */
void itoa(int n, char s[])
{
int i, sign;
if ((sign = n) < 0)
n = -n;
i = 0;
do {
s[i++] = n % 10 + '0';
} while ((n /= 10) > 0);
if (sign < 0)
s[i++] = '-';
s[i] = '\0';
/* reverse the string */
int j, k;
char c;
for (j = 0, k = i - 1; j < k; j++, k--) {
c = s[j];
s[j] = s[k];
s[k] = c;
}
}
/**
* @brief This function is executed in case of error occurrence.
*/
void Error_Handler(void)
{
while(1)
{
}
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
*/
void assert_failed(uint8_t* file, uint32_t line)
{
/* 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) */
}
#endif
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/