为什么在stm103的freertos移植例子工程里看不到SysTick的初始化？？？

52mcu

用的  “02.配套例程\04.FreeRTOS操作系统（39个例子）\V4-300_FreeRTOS实验_任务创建和删除\V4-300_FreeRTOS实验_任务创建和删除\Project\MDK-ARM(uV4”

SysTick不是用于操作系统的时钟节拍吗？？为什么在例子代码里看不到SysTick的初始化代码呢？？


void bsp_Init(void)
{
/*
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*/

/* óÅÏ輶·Ö×ééèÖÃÎa4, óÅÏèÅäÖÃoÃNVIC */
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_4);
bsp_InitUart();  /* 3õê¼»ˉ′®¿ú */
bsp_InitLed();   /* 3õê¼LEDÖ¸ê¾μƶ˿ú */
bsp_InitKey();  /* 3õê¼»ˉ°′¼ü */

}

byccc

在port.c文件里面

52mcu

@byccc  嗯确实在port.c 里有 函数  void vPortSetupTimerInterrupt( void )就是初始化SysTick的吧
在  STM32Cube_FW_F1_V1.7.0 里也有freertos的例子  有下面的函数把  TIM2 给初始化了，这应该不是用作os的时钟节拍的吧？？


HAL_StatusTypeDef HAL_InitTick (uint32_t TickPriority)
{
  RCC_ClkInitTypeDef    clkconfig;
  uint32_t              uwTimclock, uwAPB1Prescaler = 0U;
  uint32_t              uwPrescalerValue = 0U;
  uint32_t              pFLatency;
  
    /*Configure the TIM2 IRQ priority */
  HAL_NVIC_SetPriority(TIM2_IRQn, TickPriority ,0U);
  
  /* Enable the TIM2 global Interrupt */
  HAL_NVIC_EnableIRQ(TIM2_IRQn);
  
  /* Enable TIM2 clock */
  __HAL_RCC_TIM2_CLK_ENABLE();
  
  /* Get clock configuration */
  HAL_RCC_GetClockConfig(&clkconfig, &pFLatency);
  
  /* Get APB1 prescaler */
  uwAPB1Prescaler = clkconfig.APB1CLKDivider;
  
  /* Compute TIM2 clock */
  if (uwAPB1Prescaler == RCC_HCLK_DIV1)
  {
    uwTimclock = HAL_RCC_GetPCLK1Freq();
  }
  else
  {
    uwTimclock = 2*HAL_RCC_GetPCLK1Freq();
  }
  
  /* Compute the prescaler value to have TIM2 counter clock equal to 1MHz */
  uwPrescalerValue = (uint32_t) ((uwTimclock / 1000000U) - 1U);
  
  /* Initialize TIM2 */
  TimHandle.Instance = TIM2;
  
  /* Initialize TIMx peripheral as follow:
  + Period = [(TIM2CLK/1000) - 1]. to have a (1/1000) s time base.
  + Prescaler = (uwTimclock/1000000 - 1) to have a 1MHz counter clock.
  + ClockDivision = 0
  + Counter direction = Up
  */
  TimHandle.Init.Period = (1000000U / 1000U) - 1U;
  TimHandle.Init.Prescaler = uwPrescalerValue;
  TimHandle.Init.ClockDivision = 0U;
  TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
  TimHandle.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  if(HAL_TIM_Base_Init(&TimHandle) == HAL_OK)
  {
    /* Start the TIM time Base generation in interrupt mode */
    return HAL_TIM_Base_Start_IT(&TimHandle);
  }
  
  /* Return function status */
  return HAL_ERROR;
}

byccc

52mcu 发表于 2018-12-22 22:42
@byccc  嗯确实在port.c 里有 函数  void vPortSetupTimerInterrupt( void )就是初始化SysTick的吧
在 ...

是的，这个是作为HAL库的时钟节拍，默认是用滴答，因为FreeRTOS要用，所以做了重定向。

52mcu

@byccc  谢谢 讲的很明白