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Vikas Singh
Vikas Singh
Associate
November 7, 2017
Question

Problem in external interrupt on PORTB

  • November 7, 2017
  • 3 replies
  • 1695 views
Posted on November 07, 2017 at 06:31

I am using STM32F0308 Dicovery Board. I want to use external interrupt on PIN11 of PORTB. Problem is that I am not able to invoke the PORTB. Microcontroller is still uses PIN11 of PORTA. I know that pins of ports are clubbed together but I am specifying PORTB still micro is using PORTA.

I think there is some problem in this code line

SYSCFG->EXTICR[3] = SYSCFG_EXTICR3_EXTI11_PB;  

Here is code

#include'stm32f0xx.h'

volatile int portBPin10Counter;

void EXTI4_15_IRQHandler(void)

{

  if(EXTI->PR & EXTI_PR_PR11)

  {

     EXTI->PR |= EXTI_PR_PR11;

     portBPin10Counter++;

  }

  }

int main(void)

{

RCC->AHBENR |=RCC_AHBENR_GPIOBEN;

GPIOB->MODER &= ~GPIO_MODER_MODER11;

GPIOB->PUPDR &= ~GPIO_PUPDR_PUPDR11;

SYSCFG->EXTICR[3] =SYSCFG_EXTICR3_EXTI11_PB;

EXTI->RTSR |= EXTI_RTSR_TR11;

EXTI->IMR |= EXTI_IMR_MR11;

NVIC_EnableIRQ(EXTI4_15_IRQn);

NVIC_SetPriority(EXTI4_15_IRQn,1);

    while(1)

    {

    }

}

    This topic has been closed for replies.

    3 replies

    waclawek.jan
    waclawek.jan
    Super User
    November 9, 2017
    Posted on November 09, 2017 at 01:14

    Do you have SYSCFG clock enabled in RCC?

    JW

    Vikas Singh
    Vikas SinghAuthor
    Associate
    November 9, 2017
    Posted on November 09, 2017 at 05:16

    Yes this worked. Thanks. ST have not mentioned about this in code example of reference manual on page no732. Index of array EXTICR is also wrong. Final code is like this

    #include'stm32f0xx.h'

    volatile int portBPin11Counter;

    void EXTI4_15_IRQHandler(void)

    {

    if((EXTI->PR & EXTI_PR_PR11)&&(EXTI->IMR & EXTI_IMR_MR11))

    {

    EXTI->PR |= EXTI_PR_PR11;

    portBPin11Counter++;

    }

    }

    int main(void)

    {

    RCC->AHBENR |=RCC_AHBENR_GPIOCEN;

    RCC->APB2ENR |=RCC_APB2ENR_SYSCFGEN;

    SYSCFG->EXTICR[2] = (uint16_t)SYSCFG_EXTICR3_EXTI11_PC;

    EXTI ->FTSR |= EXTI_FTSR_TR11;

    EXTI->IMR |= EXTI_IMR_MR11;

    NVIC_EnableIRQ(EXTI4_15_IRQn);

    NVIC_SetPriority(EXTI4_15_IRQn,0);

    while(1)

    {

    }

    }
    waclawek.jan
    waclawek.jan
    Super User
    November 9, 2017
    Posted on November 09, 2017 at 12:24

    ST have not mentioned about this in code example of reference manual on page no732.

    Indeed. However, those code fragments are meant only as a rough guideline. It's better to use the

    http://www.st.com/en/embedded-software/stm32snippetsf0.html

    as a starting point, as they form a complete working example.

    JW

    Vikas Singh
    Vikas SinghAuthor
    Associate
    November 10, 2017
    Posted on November 10, 2017 at 08:32

    A lots of thanks for the link. I recently migrated from arduino to ST and this is really helpfull for people like me. But that refrence manual teach me how to code from data sheet. It is lengthy process but I am sure it will help in ling run. Keep up the good work.

    Pilous Droip
    Pilous Droip
    Senior
    November 9, 2017
    Posted on November 09, 2017 at 13:15

    Hi friend. I try this code on my STM32F407, and I have a problem. I have this code, but interrupt doesn't generate.

    My intterupt pin is PD4.

    int8_t PD4_init(void)

    {

    LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_GPIOD);

    LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_SYSCFG);

    SYSCFG->EXTICR[1] = (uint16_t)SYSCFG_EXTICR2_EXTI4_PD;

    LL_EXTI_EnableFallingTrig_0_31(EXTI_FTSR_TR4);

    LL_EXTI_EnableIT_0_31(EXTI_IMR_MR4);

    NVIC_EnableIRQ(EXTI4_IRQn);

    NVIC_SetPriority(EXTI4_IRQn,0);

    /* output pin with LED*/

    LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_GPIOD);

    LL_GPIO_SetPinMode(GPIOD,LL_GPIO_PIN_14,LL_GPIO_MODE_OUTPUT);

    return 0;

    }

    void EXTI4_IRQHandler (void)

    {

    if ( LL_EXTI_IsActiveFlag_0_31(EXTI_PR_PR4) && LL_EXTI_IsEnabledIT_0_31(EXTI_IMR_MR4) )

    {

    LL_EXTI_ClearFlag_0_31(EXTI_PR_PR4);

    LL_GPIO_TogglePin(GPIOD,LL_GPIO_PIN_14); //toggle with RED LED

    }

    }

    Any idea, what can be wrong?? Thank you

    waclawek.jan
    waclawek.jan
    Super User
    November 10, 2017
    Posted on November 10, 2017 at 09:57

    Can't see any obvious problem. Verify the input signal is present on pin, e.g. by toggling the LED in a trivial check in a loop in main(), with no interrupts and no other code.

    JW

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