STM32 NVIC中断优先级管理通过结构图快速理解

STM32 NVIC中断优先级管理通过结构图快速理解

---

抢占优先级和响应优先级基本常识

• 抢占优先级的级别高于响应优先级。
• 抢占优先级数值编号越小，所代表的优先级就越高；同理，响应优先级也是如此。
• HAL优先组函数：

/**
  * @brief  Sets the priority grouping field (preemption priority and subpriority)
  *         using the required unlock sequence.
  * @param  PriorityGroup: The priority grouping bits length. 
  *         This parameter can be one of the following values:
  *         @arg NVIC_PRIORITYGROUP_0: 0 bits for preemption priority
  *                                    4 bits for subpriority
  *         @arg NVIC_PRIORITYGROUP_1: 1 bits for preemption priority
  *                                    3 bits for subpriority
  *         @arg NVIC_PRIORITYGROUP_2: 2 bits for preemption priority
  *                                    2 bits for subpriority
  *         @arg NVIC_PRIORITYGROUP_3: 3 bits for preemption priority
  *                                    1 bits for subpriority
  *         @arg NVIC_PRIORITYGROUP_4: 4 bits for preemption priority
  *                                    0 bits for subpriority
  * @note   When the NVIC_PriorityGroup_0 is selected, IRQ preemption is no more possible. 
  *         The pending IRQ priority will be managed only by the subpriority. 
  * @retval None
  */
void HAL_NVIC_SetPriorityGrouping(uint32_t PriorityGroup)
{
  /* Check the parameters */
  assert_param(IS_NVIC_PRIORITY_GROUP(PriorityGroup));
  
  /* Set the PRIGROUP[10:8] bits according to the PriorityGroup parameter value */
  NVIC_SetPriorityGrouping(PriorityGroup);
}

• 对于STM32f1系列，可分配有4组：
  
• • NVIC_PRIORITYGROUP_0
    

HAL_NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_0);
HAL_NVIC_SetPriority(TIM5_IRQn, 0, 15);//中断号，抢占优先级(0),子优先级(0-15)

• • NVIC_PRIORITYGROUP_1
    

HAL_NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_1);
HAL_NVIC_SetPriority(TIM5_IRQn, 1, 7);//中断号，抢占优先级(0-1),子优先级(0-7)

• • NVIC_PRIORITYGROUP_2

HAL_NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_2);
HAL_NVIC_SetPriority(TIM5_IRQn, 3, 3);//中断号，抢占优先级(0-3),子优先级(0-3)

• • NVIC_PRIORITYGROUP_3

HAL_NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_3);
HAL_NVIC_SetPriority(TIM5_IRQn, 7, 1);//中断号，抢占优先级(0-7),子优先级(0-1)

• • NVIC_PRIORITYGROUP_4
    

HAL_NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_4);
HAL_NVIC_SetPriority(TIM5_IRQn, 15, 0);//中断号，抢占优先级(0-15),子优先级(0)