STM32F4Discovery interrupt on PortD Pin0

[bjoernprecht]

Posted on March 30, 2013 at 15:09

Hello,

i used a STM32F4Discovery. My code is at the end of this text. The programm should release a interrupt by rising edge on PortD Pin0. Then the LED toggle on PortD Pin14. This does not work. Where is the mistake? Thank you. int main (void) {   SystemInit();   GPIO_InitTypeDef GPIO_InitStructure;   EXTI_InitTypeDef EXTI_InitStructure;   NVIC_InitTypeDef NVIC_InitStructure;   RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;   GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;   GPIO_Init(GPIOD, &GPIO_InitStructure);   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;   GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;   GPIO_Init(GPIOD, &GPIO_InitStructure);   SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOD, EXTI_PinSource0);   EXTI_InitStructure.EXTI_Line = EXTI_Line0;   EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;   EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;   EXTI_InitStructure.EXTI_LineCmd = ENABLE;   EXTI_Init(&EXTI_InitStructure);   NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);   NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;   NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F;   NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;   NVIC_Init(&NVIC_InitStructure);     while(1)   {         } } void EXTI0_IRQHandler(void){   if(GPIO_ReadOutputDataBit(GPIOD, GPIO_Pin_14)){     GPIO_WriteBit(GPIOD, GPIO_Pin_14, RESET);   }else{     GPIO_WriteBit(GPIOD, GPIO_Pin_14, SET);   }     EXTI_ClearITPendingBit(EXTI_Line0); }

[Tesla DeLorean]

Posted on March 30, 2013 at 16:00

In the CMSIS model SystemInit() is called prior to main(), not a good plan to call it again.

EXTI is on the SYSCFG unit, you must enable it's clock.   /* Enable SYSCFG clock */   RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE); Also you should check/clear the interrupt source on entry, so as not to cause the handler to re-enter via a tail-chaining hazard.

[bjoernprecht]

Posted on April 01, 2013 at 13:48

Thank you