目录
中断概述
M3内核中断源
外部中断EXTI概述
输入线(以EXTI0为例)
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
3.初始化NVIC,用于处理中断
4.编写中断服务函数
5.main函数
代码示例:外部中断控制按键
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 |
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;
- 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
.
.
.
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
- 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 */
- 配置EXTI_Mode
typedef enum
{
EXTI_Mode_Interrupt = 0x00,//中断模式
EXTI_Mode_Event = 0x04
}EXTIMode_TypeDef;
- 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;
- 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
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