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gerson74
gerson74
Associate II
October 26, 2023
Solved

Interrupt priority in STM32F429

  • October 26, 2023
  • 2 replies
  • 1452 views

Good morning, I have some problems with interrupt priority on the STM32F429.
I set up a serial communication on UART1 with this priority

// USART
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init ( &NVIC_InitStructure );


I also set a TIM1 timer with this priority.

// TIM1
NVIC_InitStructure.NVIC_IRQChannel = TIM1_UP_TIM10_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init (&NVIC_InitStructure);


Although the serial priority is greater than the timer priority, if I am executing the timer interrupt routine (lasting about 200usec), I have verified that when I receive data via serial at 57600,N,8,1 (and therefore a byte every 156us ) the data is lost because it does not enter the serial interrupt routine.

Why does this happen?

 

Thank you

This topic has been closed for replies.
Best answer by TDK

> NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;

The typical configuration has 4 bits for preemption and 0 bits for subpriority, which makes this setting invalid. Have you changed the defaults?

Perhaps show what NVIC_Init does. It's not a standard function as far as I can tell.

 

2 replies

TDK
TDKBest answer
October 26, 2023

> NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;

The typical configuration has 4 bits for preemption and 0 bits for subpriority, which makes this setting invalid. Have you changed the defaults?

Perhaps show what NVIC_Init does. It's not a standard function as far as I can tell.

 

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    gerson74
    gerson74Author
    Associate II
    October 27, 2023

    I solved it by calling the function

    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);

    before initialization!!

    Thank you

     

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