STM32中断行为是怎样跳转到EXTI9_5_IRQHandler函数的？

1楼-- · 2019-07-21 07:39

在startup_stm32f10x_md.s中有如下汇编：
; Vector Table Mapped to Address 0 at Reset
            AREA RESET, DATA, READONLY
            EXPORT  __Vectors
            EXPORT  __Vectors_End
            EXPORT  __Vectors_Size

__Vectors    DCD    __initial_sp             ; Top of Stack
            DCD    Reset_Handler             ; Reset Handler
            DCD    NMI_Handler             ; NMI Handler
            DCD    HardFault_Handler       ; Hard Fault Handler
            DCD    MemManage_Handler       ; MPU Fault Handler
            DCD    BusFault_Handler          ; Bus Fault Handler
            DCD    UsageFault_Handler       ; Usage Fault Handler
            DCD    0                         ; Reserved
            DCD    0                         ; Reserved
            DCD    0                         ; Reserved
            DCD    0                         ; Reserved
            DCD    SVC_Handler             ; SVCall Handler
            DCD    DebugMon_Handler          ; Debug Monitor Handler
            DCD    0                         ; Reserved
            DCD    PendSV_Handler          ; PendSV Handler
            DCD    SysTick_Handler          ; SysTick Handler

            ; External Interrupts
            DCD    WWDG_IRQHandler          ; Window Watchdog
            DCD    PVD_IRQHandler          ; PVD through EXTI Line detect
            DCD    TAMPER_IRQHandler       ; Tamper
            DCD    RTC_IRQHandler          ; RTC
            DCD    FLASH_IRQHandler          ; Flash
            DCD    RCC_IRQHandler          ; RCC
            DCD    EXTI0_IRQHandler          ; EXTI Line 0
            DCD    EXTI1_IRQHandler          ; EXTI Line 1
            DCD    EXTI2_IRQHandler          ; EXTI Line 2
            DCD    EXTI3_IRQHandler          ; EXTI Line 3
            DCD    EXTI4_IRQHandler          ; EXTI Line 4
            DCD    DMA1_Channel1_IRQHandler ; DMA1 Channel 1
            DCD    DMA1_Channel2_IRQHandler ; DMA1 Channel 2
            DCD    DMA1_Channel3_IRQHandler ; DMA1 Channel 3
            DCD    DMA1_Channel4_IRQHandler ; DMA1 Channel 4
            DCD    DMA1_Channel5_IRQHandler ; DMA1 Channel 5
            DCD    DMA1_Channel6_IRQHandler ; DMA1 Channel 6
            DCD    DMA1_Channel7_IRQHandler ; DMA1 Channel 7
            DCD    ADC1_2_IRQHandler       ; ADC1_2
            DCD    USB_HP_CAN1_TX_IRQHandler  ; USB High Priority or CAN1 TX
            DCD    USB_LP_CAN1_RX0_IRQHandler ; USB Low  Priority or CAN1 RX0
            DCD    CAN1_RX1_IRQHandler       ; CAN1 RX1
            DCD    CAN1_SCE_IRQHandler       ; CAN1 SCE
            DCD    EXTI9_5_IRQHandler       ; EXTI Line 9..5
            DCD    TIM1_BRK_IRQHandler       ; TIM1 Break
            DCD    TIM1_UP_IRQHandler       ; TIM1 Update
            DCD    TIM1_TRG_COM_IRQHandler ; TIM1 Trigger and Commutation
            DCD    TIM1_CC_IRQHandler       ; TIM1 Capture Compare
            DCD    TIM2_IRQHandler          ; TIM2
            DCD    TIM3_IRQHandler          ; TIM3
            DCD    TIM4_IRQHandler          ; TIM4
            DCD    I2C1_EV_IRQHandler       ; I2C1 Event
            DCD    I2C1_ER_IRQHandler       ; I2C1 Error
            DCD    I2C2_EV_IRQHandler       ; I2C2 Event
            DCD    I2C2_ER_IRQHandler       ; I2C2 Error
            DCD    SPI1_IRQHandler          ; SPI1
            DCD    SPI2_IRQHandler          ; SPI2
            DCD    USART1_IRQHandler       ; USART1
            DCD    USART2_IRQHandler       ; USART2
            DCD    USART3_IRQHandler       ; USART3
            DCD    EXTI15_10_IRQHandler    ; EXTI Line 15..10
            DCD    RTCAlarm_IRQHandler       ; RTC Alarm through EXTI Line
            DCD    USBWakeUp_IRQHandler    ; USB Wakeup from suspend
__Vectors_End
这些都是定义中断向量表的。在我们的C语言里如果有定义EXTI9_5_IRQHandler函数，就会进入对应的中断，是因为EXTI9_5_IRQHandler在startup_stm32f10x_md.s中有声明。
对于汇编DCD的作用可以参考：http://blog.sina.com.cn/s/blog_5e0fa9860100u7tl.html
以上是我的理解，大家共同进步。