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Solved: STM32F4Discovery EXTI Multiple Interrupts

Just Matt
Associate III
Posted on January 03, 2014 at 03:17

EDIT: Solved by clive1! See post below.

Hi (again), I'm tinkering with Interrupts this week. I'n the example code I have provided below, The Green light flashes (as expected) in the loop. The EXTI0 fires when I bring the PA0 pin high. However, when I bring the PC5 pin high nothing happens :( Not sure, what i'm doing wrong, or is there a special way of handeling multiple interrupts? Google and the (soso) search here didn't show much. As always any help is appreciated!

#include <stm32f4xx_gpio.h>
#include <stm32f4xx_rcc.h>
#include <stm32f4xx_exti.h>
#include <stm32f4xx_syscfg.h>
#include <stm32f4xx.h>
#include <misc.h>
void
InitGPIO(GPIO_TypeDef*, uint16_t, GPIOMode_TypeDef);
void
Attach_GPIO_Interrupt(uint8_t, uint8_t, uint32_t, EXTITrigger_TypeDef, uint8_t);
void
Delay();
int
main()
{
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
InitGPIO(GPIOA, GPIO_Pin_0, GPIO_Mode_IN); 
//initialise PA0 is input
InitGPIO(GPIOC, GPIO_Pin_5, GPIO_Mode_IN);
// PC5 as input
//Green
InitGPIO(GPIOD, GPIO_Pin_12, GPIO_Mode_OUT);
//Blue
InitGPIO(GPIOD, GPIO_Pin_15, GPIO_Mode_OUT);
//Orange
InitGPIO(GPIOD, GPIO_Pin_13, GPIO_Mode_OUT);
//attach interrupt to GPIO PA0
Attach_GPIO_Interrupt(EXTI_PortSourceGPIOA, EXTI_PinSource0, EXTI_Line0, EXTI_Trigger_Rising, 1);
//interrupt to PC5
Attach_GPIO_Interrupt(EXTI_PortSourceGPIOC, EXTI_PinSource5, EXTI_Line2, EXTI_Trigger_Rising_Falling, 1);
for
(;;)
{
GPIO_WriteBit(GPIOD, GPIO_Pin_12, Bit_SET);
Delay();
GPIO_WriteBit(GPIOD, GPIO_Pin_12, Bit_RESET);
Delay();
}
}
extern
''C''
void
EXTI0_IRQHandler(
void
) 
//EXTI0 ISR
{
if
(EXTI_GetITStatus(EXTI_Line0) != RESET) 
//check if EXTI line is asserted
{
EXTI_ClearFlag(EXTI_Line0); 
//clear interrupt
//Enter your code here
GPIO_WriteBit(GPIOD, GPIO_Pin_15, Bit_SET);
Delay();
GPIO_WriteBit(GPIOD, GPIO_Pin_15, Bit_RESET);
}
}
extern
''C''
void
EXTI2_IRQHandler(
void
) 
//EXTI2 ISR
{
if
(EXTI_GetITStatus(EXTI_Line2) != RESET) 
//check if EXTI line is asserted
{
EXTI_ClearFlag(EXTI_Line2); 
//clear interrupt
//Enter your code here
GPIO_WriteBit(GPIOD, GPIO_Pin_13, Bit_SET);
Delay();
GPIO_WriteBit(GPIOD, GPIO_Pin_13, Bit_RESET);
}
}
void
Delay()
{
int
i;
for
(i = 0; i < 1000000; i++)
asm(
''nop''
);
}
void
InitGPIO(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin, GPIOMode_TypeDef GPIO_Mode)
{
GPIOPuPd_TypeDef PuPdMode = GPIO_PuPd_NOPULL;
GPIO_InitTypeDef GPIO_InitStructure;
switch
(GPIO_Mode)
{
case
GPIO_Mode_OUT:
PuPdMode = GPIO_PuPd_NOPULL; 
//digital output. Not using open drain mode as I do not know how that operates
break
;
case
GPIO_Mode_IN:
PuPdMode = GPIO_PuPd_NOPULL; 
//digital read have Pin as input floating
break
;
case
GPIO_Mode_AN:
PuPdMode = GPIO_PuPd_NOPULL; 
//for analogue read have Pin as input floating
break
;
case
GPIO_Mode_AF: 
//need to do a remapping if using alternate functions
PuPdMode = GPIO_PuPd_UP; 
//for PWM have not looked at accounting for the various other alternate functions
break
;
}
GPIO_InitStructure.GPIO_Pin = GPIO_Pin;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode;
//GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //used for digital output and PWM output
//this setting does not matter for ADC and digital read
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_25MHz;
GPIO_InitStructure.GPIO_PuPd = PuPdMode;
GPIO_Init(GPIOx, &GPIO_InitStructure);
}
void
Attach_GPIO_Interrupt(uint8_t EXTI_PortSourceGPIOx, uint8_t EXTI_PinSourcex, uint32_t EXTI_Line,
EXTITrigger_TypeDef EXTI_Trigger, uint8_t Priority)
{
uint8_t EXTI_IRQn = 0;
switch
(EXTI_Line)
{
case
0x1:
EXTI_IRQn = EXTI0_IRQn;
break
;
case
0x2:
EXTI_IRQn = EXTI1_IRQn;
break
;
case
0x4:
EXTI_IRQn = EXTI2_IRQn;
break
;
case
0x8:
EXTI_IRQn = EXTI3_IRQn;
break
;
case
0x10:
EXTI_IRQn = EXTI4_IRQn;
break
;
case
0x20: 
case
0x40: 
case
0x80: 
case
0x100: 
case
0x200:
EXTI_IRQn = EXTI9_5_IRQn;
break
;
case
0x400: 
case
0x800: 
case
0x1000: 
case
0x2000: 
case
0x4000: 
case
0x8000:
EXTI_IRQn = EXTI15_10_IRQn;
break
;
}
/* Connect EXTI Line to appropriate GPIO Pin */
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOx, EXTI_PinSourcex);
NVIC_InitTypeDef NVIC_InitStructure;
EXTI_InitTypeDef EXTI_InitStructure;
/* Configure EXTI Line */
EXTI_InitStructure.EXTI_Line = EXTI_Line;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
/* Enable and set EXTI Line Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = EXTI_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = Priority;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}

2 REPLIES 2
Posted on January 03, 2014 at 03:57

Pin 5 would be Exti line 5, into EXTI9_5_IRQHandler

Tips, buy me a coffee, or three.. PayPal Venmo Up vote any posts that you find helpful, it shows what's working..
Just Matt
Associate III
Posted on January 03, 2014 at 04:26

Once again, Thanks Clive1! 

12.2.2 of the Reference Manual completely missed it >_<

-Matt