STM32 NVIC

在stm32中是要配置nvic的。何为nvic,对于我这样的初学者来说,直观感受就是在设置为中断后 还需要配置 中断的优先级nvic就是搞这个的、

那么具体的需要配置些什么那?

void NVIC_Configuration(void)
{

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); //设置NVIC中断分组2:2位抢占优先级,2位响应优先级

}

NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn; //使能按键WK_UP所在的外部中断通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02; //抢占优先级2,
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x03; //子优先级3
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //使能外部中断通道
NVIC_Init(&NVIC_InitStructure);

   

NVIC_InitStructure.NVIC_IRQChannel //  通道在头文件中 stm32f10x的定义
 
typedef enum IRQn
{
/******  Cortex-M3 Processor Exceptions Numbers ***************************************************/
  NonMaskableInt_IRQn         = -14,    /*!< 2 Non Maskable Interrupt                             */
  MemoryManagement_IRQn       = -12,    /*!< 4 Cortex-M3 Memory Management Interrupt              */
  BusFault_IRQn               = -11,    /*!< 5 Cortex-M3 Bus Fault Interrupt                      */
  UsageFault_IRQn             = -10,    /*!< 6 Cortex-M3 Usage Fault Interrupt                    */
  SVCall_IRQn                 = -5,     /*!< 11 Cortex-M3 SV Call Interrupt                       */
  DebugMonitor_IRQn           = -4,     /*!< 12 Cortex-M3 Debug Monitor Interrupt                 */
  PendSV_IRQn                 = -2,     /*!< 14 Cortex-M3 Pend SV Interrupt                       */
  SysTick_IRQn                = -1,     /*!< 15 Cortex-M3 System Tick Interrupt                   */
 
/******  STM32 specific Interrupt Numbers *********************************************************/
  WWDG_IRQn                   = 0,      /*!< Window WatchDog Interrupt                            */
  PVD_IRQn                    = 1,      /*!< PVD through EXTI Line detection Interrupt            */
  TAMPER_IRQn                 = 2,      /*!< Tamper Interrupt                                     */
  RTC_IRQn                    = 3,      /*!< RTC global Interrupt                                 */
  FLASH_IRQn                  = 4,      /*!< FLASH global Interrupt                               */
  RCC_IRQn                    = 5,      /*!< RCC global Interrupt                                 */
  EXTI0_IRQn                  = 6,      /*!< EXTI Line0 Interrupt                                 */
  EXTI1_IRQn                  = 7,      /*!< EXTI Line1 Interrupt                                 */
  EXTI2_IRQn                  = 8,      /*!< EXTI Line2 Interrupt                                 */
  EXTI3_IRQn                  = 9,      /*!< EXTI Line3 Interrupt                                 */
  EXTI4_IRQn                  = 10,     /*!< EXTI Line4 Interrupt                                 */
  DMA1_Channel1_IRQn          = 11,     /*!< DMA1 Channel 1 global Interrupt                      */
  DMA1_Channel2_IRQn          = 12,     /*!< DMA1 Channel 2 global Interrupt                      */
  DMA1_Channel3_IRQn          = 13,     /*!< DMA1 Channel 3 global Interrupt                      */
  DMA1_Channel4_IRQn          = 14,     /*!< DMA1 Channel 4 global Interrupt                      */
  DMA1_Channel5_IRQn          = 15,     /*!< DMA1 Channel 5 global Interrupt                      */
  DMA1_Channel6_IRQn          = 16,     /*!< DMA1 Channel 6 global Interrupt                      */
  DMA1_Channel7_IRQn          = 17,     /*!< DMA1 Channel 7 global Interrupt                      */
 
#ifdef STM32F10X_LD
  ADC1_2_IRQn                 = 18,     /*!< ADC1 and ADC2 global Interrupt                       */
  USB_HP_CAN1_TX_IRQn         = 19,     /*!< USB Device High Priority or CAN1 TX Interrupts       */
  USB_LP_CAN1_RX0_IRQn        = 20,     /*!< USB Device Low Priority or CAN1 RX0 Interrupts       */
  CAN1_RX1_IRQn               = 21,     /*!< CAN1 RX1 Interrupt                                   */
  CAN1_SCE_IRQn               = 22,     /*!< CAN1 SCE Interrupt                                   */
  EXTI9_5_IRQn                = 23,     /*!< External Line[9:5] Interrupts                        */
  TIM1_BRK_IRQn               = 24,     /*!< TIM1 Break Interrupt                                 */
  TIM1_UP_IRQn                = 25,     /*!< TIM1 Update Interrupt                                */
  TIM1_TRG_COM_IRQn           = 26,     /*!< TIM1 Trigger and Commutation Interrupt               */
  TIM1_CC_IRQn                = 27,     /*!< TIM1 Capture Compare Interrupt                       */
  TIM2_IRQn                   = 28,     /*!< TIM2 global Interrupt                                */
  TIM3_IRQn                   = 29,     /*!< TIM3 global Interrupt                                */
  I2C1_EV_IRQn                = 31,     /*!< I2C1 Event Interrupt                                 */
  I2C1_ER_IRQn                = 32,     /*!< I2C1 Error Interrupt                                 */
  SPI1_IRQn                   = 35,     /*!< SPI1 global Interrupt                                */
  USART1_IRQn                 = 37,     /*!< USART1 global Interrupt                              */
  USART2_IRQn                 = 38,     /*!< USART2 global Interrupt                              */
  EXTI15_10_IRQn              = 40,     /*!< External Line[15:10] Interrupts                      */
  RTCAlarm_IRQn               = 41,     /*!< RTC Alarm through EXTI Line Interrupt                */
  USBWakeUp_IRQn              = 42      /*!< USB Device WakeUp from suspend through EXTI Line Interrupt */    
#endif /* STM32F10X_LD */  

 

 

     

STM32有43个channel的settable的中断源;AIRC(Application Interrupt and Reset Register)寄存器中有用于指定优先级的4 bits。这4个bits用于分配preemption优先级和sub优先级,在STM32的固件库中定义如下
#define NVIC_PriorityGroup_0 ((u32)0x700)
#define NVIC_PriorityGroup_1 ((u32)0x600)
#define NVIC_PriorityGroup_2 ((u32)0x500)
#define NVIC_PriorityGroup_3 ((u32)0x400)
#define NVIC_PriorityGroup_4 ((u32)0x300) 

每个工程只能有一种分组方式:

按NVIC_PriorityGroup_0来分组:抢占优先级为1个,子优先级为16个;

按NVIC_PriorityGroup_1来分组:抢占优先级为2个,子优先级为8个;

按NVIC_PriorityGroup_2来分组:抢占优先级为4个,子优先级为4个;

按NVIC_PriorityGroup_3来分组:抢占优先级为8个,子优先级为2个;

按NVIC_PriorityGroup_0来分组:抢占优先级为16个,子优先级为1个;

抢占优先级高的中断可以打断抢占优先级低的中断;抢占优先级相同时比较响应优先级(子优先级)。

先设定分组方式

例:NVIC_PriorityGroupConfig(NVIC_PriorityGroup_4);    //按NVIC_PriorityGroup_4来分组

此时,有一中断EXTI0_IRQChannel,你指定他为抢占优先级8,则
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 8; // 指定抢占式优先级别,可取0-15

又有1中断SPI1_IRQChannel,设定如下
NVIC_InitStructure.NVIC_IRQChannel = SPI1_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; // 指定抢占式优先级别,可取0-15

则SPI1_IRQChannel的抢占优先级高,EXTI0_IRQChannel做事的时候可以打断(嵌套)

 

又:若分组方式为:NVIC_PriorityGroupConfig(NVIC_PriorityGroup_3);    //按NVIC_PriorityGroup_3来分组

此时就有8个抢占优先级,2个子优先级;

EXTI0_IRQChannel中断,你指定他为抢占优先级3,则:
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; // 指定抢占式优先级别,可取0-7
还需要指定他的阶层:
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; // 指定响应优先级别,可取0-1

又有TIM2_IRQn中断,设定如下:

NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn; 
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;// 指定抢占式优先级别,可取0-7

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; // 指定响应优先级别,可取0-1

由于抢占优先级相同,响应优先级EXTI0_IRQChannel中断高于TIM2_IRQn中断,所以EXTI0_IRQChannel可以打断TIM2_IRQn;

还有一USB_LP_CAN1_RX0_IRQn,设定如下:

NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn;   //CAN1 RX0中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  //抢占优先级0
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;   //响应优先级别0,可取0-1

USB_LP_CAN1_RX0_IRQn优先级最高,前两中断发生时,它都可以打断。

附:

void NVIC_Config(void)

{     

  

NVIC_InitTypeDef NVIC_InitStructure;

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_3);//一个工程中只能使用一种分组方式
NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn; //CAN1 RX0中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //抢占优先级0
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //子优先级为0
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;// 指定抢占式优先级别,可取0-7
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; // 指定响应优先级别,可取0-1
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; // 指定抢占式优先级别,可取0-7
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; // 指定响应优先级别,可取0-1
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);

}

 

posted @ 2016-07-12 15:12  张飞online  阅读(1602)  评论(0编辑  收藏  举报