STM32f407 MCU two interrupts at some time

ciel076 · ‎2015-07-24

Posted on July 25, 2015 at 02:13

I used TIMER 2. It's interrupt time is 1us.

I made one long pulse and short pulse using GPIO output pin and TIMER 2.

but sometimes, interrupts occurred two times.

First figure is the result I want to get.

Second figure is the result I can get now.

At second figure the red circle is an error I think.

It's shivering in trigger mode.

Here is my code

void TIM2_IRQHandler(void)

{

//TIM_ClearITPendingBit(TIM2, TIM_IT_Update);

assert_param(IS_TIM_ALL_PERIPH(TIM2));

TIM2->SR = (uint16_t)~0x0001;

//////Enable pin wait.(1us)

for(a=0;a<33;a++){

GPIOB->BSRRL = GPIO_Pin_0;

}

//wait(300ns)

for(a=0;a<10;a++){

GPIOB->BSRRH = GPIO_Pin_0;}

//one more short pulse(20ns)

GPIOB->BSRRL = GPIO_Pin_0;

GPIOB->BSRRH = GPIO_Pin_0;

}

Tesla DeLorean · ‎2015-07-24

Posted on July 25, 2015 at 03:13

Suggest you qualify the source of the interrupt, and consider if the problem is elsewhere in your code.

Tips, Buy me a coffee, or three.. PayPal Venmo
Up vote any posts that you find helpful, it shows what's working..

ciel076 · ‎2015-07-24

Posted on July 25, 2015 at 06:07

This is my Timer setting

void TIMER2_Init(void)

{

TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;

TIM_TimeBaseStructure.TIM_Period = 9;

TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;

TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

TIM_TimeBaseStructure.TIM_RepetitionCounter = 0x0000;

TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

TIM_PrescalerConfig(TIM2, 83, TIM_PSCReloadMode_Immediate);

TIM_ClearFlag(TIM2, TIM_FLAG_Update);

TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);

TIM_Cmd(TIM2, ENABLE);

}