中断概述
中断：打断CPU正常程序运行，转去执行中断服务函数的内容，然后再回来执行原来的程序
NVIC：嵌套向量中断控制器，属于内核外设，管理怎与中断相关的功能
bit7 |
bit6 |
bit5 |
bit4 |
bit3 |
bit2 |
bit1 |
bit0 |
用于表达优先级 |
没用，恒定为0 |
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typedef struct { uint8_t NVIC_IRQChannel; //中断源 uint8_t NVIC_IRQChannelPreemptionPriority; //抢占优先级 uint8_t NVIC_IRQChannelSubPriority; //子优先级 FunctionalState NVIC_IRQChannelCmd; //使能或失能 } NVIC_InitTypeDef;
1.NVIC_IRQChannel ：对于RCT6来说，它的中断源如上图所示，在stm32f103.h中已经配置好寄存器，直接调用即可，下图中，RCT6主要用的是STM32F103X_HD的中断源
M3内核中断源
/****** 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 */ 外设中断源 /****** 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_HD 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 */ TIM4_IRQn = 30, /*!< TIM4 global Interrupt */ I2C1_EV_IRQn = 31, /*!< I2C1 Event Interrupt */ I2C1_ER_IRQn = 32, /*!< I2C1 Error Interrupt */ I2C2_EV_IRQn = 33, /*!< I2C2 Event Interrupt */ I2C2_ER_IRQn = 34, /*!< I2C2 Error Interrupt */ SPI1_IRQn = 35, /*!< SPI1 global Interrupt */ SPI2_IRQn = 36, /*!< SPI2 global Interrupt */ USART1_IRQn = 37, /*!< USART1 global Interrupt */ USART2_IRQn = 38, /*!< USART2 global Interrupt */ USART3_IRQn = 39, /*!< USART3 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 */ TIM8_BRK_IRQn = 43, /*!< TIM8 Break Interrupt */ TIM8_UP_IRQn = 44, /*!< TIM8 Update Interrupt */ TIM8_TRG_COM_IRQn = 45, /*!< TIM8 Trigger and Commutation Interrupt */ TIM8_CC_IRQn = 46, /*!< TIM8 Capture Compare Interrupt */ ADC3_IRQn = 47, /*!< ADC3 global Interrupt */ FSMC_IRQn = 48, /*!< FSMC global Interrupt */ SDIO_IRQn = 49, /*!< SDIO global Interrupt */ TIM5_IRQn = 50, /*!< TIM5 global Interrupt */ SPI3_IRQn = 51, /*!< SPI3 global Interrupt */ UART4_IRQn = 52, /*!< UART4 global Interrupt */ UART5_IRQn = 53, /*!< UART5 global Interrupt */ TIM6_IRQn = 54, /*!< TIM6 global Interrupt */ TIM7_IRQn = 55, /*!< TIM7 global Interrupt */ DMA2_Channel1_IRQn = 56, /*!< DMA2 Channel 1 global Interrupt */ DMA2_Channel2_IRQn = 57, /*!< DMA2 Channel 2 global Interrupt */ DMA2_Channel3_IRQn = 58, /*!< DMA2 Channel 3 global Interrupt */ DMA2_Channel4_5_IRQn = 59 /*!< DMA2 Channel 4 and Channel 5 global Interrupt */ #endif /* STM32F10X_HD */
外部中断EXTI概述
输入线（以EXTI0为例）
PA0~PG0 EXTI0
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PA15~PG15 EXTI15
EXTI 16——PVD输出
EXTI 17——RTC闹钟事件
EXTI 18——USB唤醒事件
EXTI 19——以太网唤醒事件(只适用于互联型产品) Cotex-3无该项功能
注意是AFIO寄存器控制着外部中断
程序流程
1.初始化要连接到EXTI的GPIO
2.初始化EXTI用于产生的中断/事件
EXTI_TypeDef一个外部中断的结构体
（1）初始化输入线，选择输入线的时候要操作AFIO寄存器（外部中断配置寄存器），所以要先打开它的时钟，它的时钟线恰好挂载到RCCAPB2Per上
（2）选择输入线
//选择输入线，第一个参数是GPIO_PortSourceGPIOx（x=A~G）,第二个参数是GPIO_PinSourcex(x=0~15)
GPIO_EXTILineConfig(GPIO_PortSourceGPIOA,GPIO_PinSource0);
下面是关于这个函数的定义
/** * @brief Selects the GPIO pin used as EXTI Line. * @param GPIO_PortSource: selects the GPIO port to be used as source for EXTI lines. * This parameter can be GPIO_PortSourceGPIOx where x can be (A..G). * @param GPIO_PinSource: specifies the EXTI line to be configured. * This parameter can be GPIO_PinSourcex where x can be (0..15). * @retval None */ void GPIO_EXTILineConfig(uint8_t GPIO_PortSource, uint8_t GPIO_PinSource) { uint32_t tmp = 0x00; /* Check the parameters */ assert_param(IS_GPIO_EXTI_PORT_SOURCE(GPIO_PortSource)); assert_param(IS_GPIO_PIN_SOURCE(GPIO_PinSource)); tmp = ((uint32_t)0x0F) << (0x04 * (GPIO_PinSource & (uint8_t)0x03)); AFIO->EXTICR[GPIO_PinSource >> 0x02] &= ~tmp; AFIO->EXTICR[GPIO_PinSource >> 0x02] |= (((uint32_t)GPIO_PortSource) << (0x04 * (GPIO_PinSource & (uint8_t)0x03))); } /**
（2）然后，配置EXTI结构体的几个参数
1.配置EXTI_Line,可选参数如下
EXTI_InitStructure.EXTI_Line=EXTI_Line0; #define EXTI_Line0 ((uint32_t)0x00001) /*!< External interrupt line 0 */ #define EXTI_Line1 ((uint32_t)0x00002) /*!< External interrupt line 1 */ #define EXTI_Line2 ((uint32_t)0x00004) /*!< External interrupt line 2 */ #define EXTI_Line3 ((uint32_t)0x00008) /*!< External interrupt line 3 */ #define EXTI_Line4 ((uint32_t)0x00010) /*!< External interrupt line 4 */ #define EXTI_Line5 ((uint32_t)0x00020) /*!< External interrupt line 5 */ #define EXTI_Line6 ((uint32_t)0x00040) /*!< External interrupt line 6 */ #define EXTI_Line7 ((uint32_t)0x00080) /*!< External interrupt line 7 */ #define EXTI_Line8 ((uint32_t)0x00100) /*!< External interrupt line 8 */ #define EXTI_Line9 ((uint32_t)0x00200) /*!< External interrupt line 9 */ #define EXTI_Line10 ((uint32_t)0x00400) /*!< External interrupt line 10 */ #define EXTI_Line11 ((uint32_t)0x00800) /*!< External interrupt line 11 */ #define EXTI_Line12 ((uint32_t)0x01000) /*!< External interrupt line 12 */ #define EXTI_Line13 ((uint32_t)0x02000) /*!< External interrupt line 13 */ #define EXTI_Line14 ((uint32_t)0x04000) /*!< External interrupt line 14 */ #define EXTI_Line15 ((uint32_t)0x08000) /*!< External interrupt line 15 */ #define EXTI_Line16 ((uint32_t)0x10000) /*!< External interrupt line 16 Connected to the PVD Output */ #define EXTI_Line17 ((uint32_t)0x20000) /*!< External interrupt line 17 Connected to the RTC Alarm event */ #define EXTI_Line18 ((uint32_t)0x40000) /*!< External interrupt line 18 Connected to the USB Device/USB OTG FS Wakeup from suspend event */ #define EXTI_Line19 ((uint32_t)0x80000) /*!< External interrupt line 19 Connected to the Ethernet Wakeup event */
2.配置EXTI_Mode
typedef enum { EXTI_Mode_Interrupt = 0x00,//中断模式 EXTI_Mode_Event = 0x04 }EXTIMode_TypeDef;
3.配置中断发生的触发方式
typedef enum { EXTI_Trigger_Rising = 0x08, EXTI_Trigger_Falling = 0x0C, EXTI_Trigger_Rising_Falling = 0x10 }EXTITrigger_TypeDef;
4.配置使能ENABLE，DISABLE；
记得把配置好的结构体写到寄存器当中
综上，我们已经配置完黑圈1部分的寄存器；接下来我们要配置橙圈2部分的寄存器
3.初始化NVIC，用于处理中断
中断服务函数编程顺序
- 使能中断请求
- 配置中断优先级分组
- 配置NVIC寄存器，初始化NVIC_InitTypeDef
- 将配置好的结构体写到寄存器中
- 编写中断服务函数
（1）配置中断优先级分组
/** * @brief Configures the priority grouping: pre-emption priority and subpriority. * @param NVIC_PriorityGroup: specifies the priority grouping bits length. * This parameter can be one of the following values: * @arg NVIC_PriorityGroup_0: 0 bits for pre-emption priority * 4 bits for subpriority * @arg NVIC_PriorityGroup_1: 1 bits for pre-emption priority * 3 bits for subpriority * @arg NVIC_PriorityGroup_2: 2 bits for pre-emption priority * 2 bits for subpriority * @arg NVIC_PriorityGroup_3: 3 bits for pre-emption priority * 1 bits for subpriority * @arg NVIC_PriorityGroup_4: 4 bits for pre-emption priority * 0 bits for subpriority * @retval None */ void NVIC_PriorityGroupConfig(uint32_t NVIC_PriorityGroup) { /* Check the parameters */ assert_param(IS_NVIC_PRIORITY_GROUP(NVIC_PriorityGroup)); /* Set the PRIGROUP[10:8] bits according to NVIC_PriorityGroup value */ SCB->AIRCR = AIRCR_VECTKEY_MASK | NVIC_PriorityGroup; } 例如：NVIC_PriorityGroup_2: 2 bits for pre-emption priority * 2 bits for subpriority
主优先级有2个bit(4个级数,0~3)，子优先级也有2个bit；所以总共可以有16个中断先后顺序
（2）然后，配置NVIC结构体里面的参数
（3）配置中断源
中断源在上面M3内核中断源有讲到，注意RCT6对应的是HD
（4）把结构体写入中断寄存器中
//写入主优先级 NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1; //写入从优先级 NVIC_InitStructure.NVIC_IRQChannelSubPriority=1; //使能 NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE; //把配置好的结构体写入寄存器内 NVIC_Init(&NVIC_InitStructure);
4.编写中断服务函数
中断服务函数必须和启动文件中的中断服务函数名字是一样的，当然，你也可以改，但没必要
打开startup_stm32f10x hd_s文件，找到86行
定义好名字后，要调用ITStatus EXTI_GetITStatus(uint32_t EXTI_Line);来检测电平变化
然后，这个函数就会返回 (SET or RESET).
产生中断，SET
未产生中断，RESET
这时我们只需用该函数判断
if(EXTI_GetITStatus(KEY1_EXTI_Line)!=RESET)
对于这个函数
/** * @brief Checks whether the specified EXTI line is asserted or not. * @param EXTI_Line: specifies the EXTI line to check. * This parameter can be: * @arg EXTI_Linex: External interrupt line x where x(0..19) * @retval The new state of EXTI_Line (SET or RESET). */ ITStatus EXTI_GetITStatus(uint32_t EXTI_Line) { ITStatus bitstatus = RESET; uint32_t enablestatus = 0; /* Check the parameters */ assert_param(IS_GET_EXTI_LINE(EXTI_Line)); enablestatus = EXTI->IMR & EXTI_Line; if (((EXTI->PR & EXTI_Line) != (uint32_t)RESET) && (enablestatus != (uint32_t)RESET)) { bitstatus = SET; } else { bitstatus = RESET; } return bitstatus; }
输入的参数是挂载的中断线
EXTI_Linex: External interrupt line x where x(0..19)
最后，记得把SET/RESET中断标志位消除，该函数输入参数也是挂载的中断线
/** * @brief Clears the EXTI's line pending bits. * @param EXTI_Line: specifies the EXTI lines to clear. * This parameter can be any combination of EXTI_Linex where x can be (0..19). * @retval None */ void EXTI_ClearITPendingBit(uint32_t EXTI_Line) { /* Check the parameters */ assert_param(IS_EXTI_LINE(EXTI_Line)); EXTI->PR = EXTI_Line; }
5.main函数
代码示例：外部中断控制按键
代码就是简单的按一次，LED取反一次。以后有空的话就写一篇关于按键单击，双击，三击，短按，长按的博客
