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NVIC_EnableIRQ : enables only one interrupt at a time?

Looking at the one of the implementations of NVIC_EnableIRQ, Im wondering how the ISER works

static __INLINE void NVIC_EnableIRQ(IRQn_Type IRQn)
{
  NVIC->ISER[((uint32_t)(IRQn) >> 5)] = (1 << ((uint32_t)(IRQn) & 0x1F)); /* enable interrupt */
}

Calling the above two consequitve times with a different IRQn, will erase the enable of the previous interrupt. Does it mean I can enable one interrupt at a time?

NVIC_EnableIRQ(8);   // enables IRQ8

NVIC_EnableIRQ(7);   // enables IRQ7 but disables IRQ8 ?!?

Correct, or do I miss something?

Further, can I set an IER of a peripheral device without enabling its interrupt ?!?

Thanks in advance !

Parents
  • Further, can I set an IER of a peripheral device without enabling its interrupt ?!?

    For example, can I set the IER below

    LPC_UART3->IER = 0x00000005UL;            // Enable UART3 interrupt RBR ans RLS

    without calling before it

    NVIC_EnableIRQ(UART3_IRQn);

    ?

    Where do I need to use 

    NVIC_EnableIRQ

    and/or where do I need to set the corresponding peripheral

     

    IER

    ?

Reply
  • Further, can I set an IER of a peripheral device without enabling its interrupt ?!?

    For example, can I set the IER below

    LPC_UART3->IER = 0x00000005UL;            // Enable UART3 interrupt RBR ans RLS

    without calling before it

    NVIC_EnableIRQ(UART3_IRQn);

    ?

    Where do I need to use 

    NVIC_EnableIRQ

    and/or where do I need to set the corresponding peripheral

     

    IER

    ?

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