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在liteos中通过LOS_HwiCreate来注册一个中断，举例如下：UINT32 Example_Interrupt(VOID){    UINTPTR uvIntSave;    uvIntSave = LOS_IntLock();    Example_Exti0_Init();#核心是调用这个函数来新建中断，第一个形参是中断号    LOS_HwiCreate(6, 0, 0, User_IRQHandler, 0);//create interrupt    LOS_IntRestore(uvIntSave);    return LOS_OK;}继续看看LITE_OS_SEC_TEXT_INIT UINT32 LOS_HwiCreate( HWI_HANDLE_T  uwHwiNum,                                      HWI_PRIOR_T   usHwiPrio,                                      HWI_MODE_T    usMode,                                      HWI_PROC_FUNC pfnHandler,                                      HWI_ARG_T     uwArg ){    UINTPTR uvIntSave;#这个数组保存这个所有中断号对应的中断处理函数    if (m_pstHwiForm[uwHwiNum + OS_SYS_VECTOR_CNT] != (HWI_PROC_FUNC)osHwiDefaultHandler)    {        return OS_ERRNO_HWI_ALREADY_CREATED;    }    uvIntSave = LOS_IntLock();#根据中断号更新m_pstHwiForm数组中中断号对应的中断处理函数#if (OS_HWI_WITH_ARG == YES)    osSetVector(uwHwiNum, pfnHandler, uwArg);#else    osSetVector(uwHwiNum, pfnHandler);#endif#使能这个中断    NVIC_EnableIRQ((IRQn_Type)uwHwiNum);#设置这个中断的优先级    NVIC_SetPriority((IRQn_Type)uwHwiNum, usHwiPrio);    LOS_IntRestore(uvIntSave);    return LOS_OK;}可见osSetVector 中更新了两个数组，其中数组m_pstHwiForm 的中每个回调函数都是osInterrupt在osInterrupt;中会调用pfnVector#define osSetVector(uwNum, pfnVector)       \    m_pstHwiForm[uwNum + OS_SYS_VECTOR_CNT] = osInterrupt;\    m_pstHwiSlaveForm[uwNum + OS_SYS_VECTOR_CNT] = pfnVector;#endif为什么会在LOS_HwiCreate中会判断中断的默认处理函数是osHwiDefaultHandlerif (m_pstHwiForm[uwHwiNum + OS_SYS_VECTOR_CNT] != (HWI_PROC_FUNC)osHwiDefaultHandler)    {        return OS_ERRNO_HWI_ALREADY_CREATED;    }这个是因为在下面的函数中会默认对m_pstHwiForm中的所有中断号赋一个初值，所以这里增加一个判断是防止中断的重复注册LITE_OS_SEC_TEXT_INIT VOID osHwiInit(){    UINT32 uwIndex;    for(uwIndex = OS_SYS_VECTOR_CNT; uwIndex < OS_VECTOR_CNT; uwIndex++)    {        m_pstHwiForm[uwIndex] = (HWI_PROC_FUNC)osHwiDefaultHandler;    }    /* Interrupt vector table location */    SCB->VTOR = (UINT32)m_pstHwiForm;#if (__CORTEX_M >= 0x03U)  /* only for Cortex-M3 and above */    NVIC_SetPriorityGrouping(OS_NVIC_AIRCR_PRIGROUP);#endif    return;}

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