EXTI interference problem stm32f4

[haythem]

Posted on April 03, 2015 at 21:22

Hi,

I have a problem with my stm32f4 (I work with keil)…I was configured tow DC motos with PWM with TIM3 connected to PA7 PA6 , PB0 , and PB1 pins. To know the motors rotation I was use tow simple optical encoder that return numeric value 0V and 5V. I read the impulsion returned by encoder with EXTI (PA0 , PA1) . In the early when I turn the motors manually, everything works perfectly. But when they turn with PWM, one motor I that the tow encoder return values. I think there is some interference between PWM and EXT. Please so one could give me an idea to solve my problem. Thank you in advance.main file

1. EXTI_InitTypeDef   EXTI_InitStructure;
2. NVIC_InitTypeDef   NVIC_InitStructure;
3.  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
4.  GPIO_InitStructure.GPIO_Pin =GPIO_Pin_0|GPIO_Pin_1;
5.     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
6.     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
7.     GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
8.     GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN;
9.     GPIO_Init(GPIOA, &GPIO_InitStructure);
10. /*******EXTI INPUT PA0*********/
11. SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource0);
12. EXTI_InitStructure.EXTI_Line = EXTI_Line0;
13.   EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
14.   EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;  
15.   EXTI_InitStructure.EXTI_LineCmd = ENABLE;
16.   EXTI_Init(&EXTI_InitStructure);
17.   /* Enable and set EXTI Line0 Interrupt to the lowest priority */
18.   NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
19.   NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
20.   NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
21.   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
22.   NVIC_Init(&NVIC_InitStructure);
23. /*******EXTI INPUT PA1*********/
24. SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource1);
25.  EXTI_InitStructure.EXTI_Line = EXTI_Line1;
26.   EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
27.   EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;  
28.   EXTI_InitStructure.EXTI_LineCmd = ENABLE;
29.   EXTI_Init(&EXTI_InitStructure);
30.   /* Enable and set EXTI Line0 Interrupt to the lowest priority */
31.   NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;
32.   NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
33.   NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
34.   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
35.   NVIC_Init(&NVIC_InitStructure);

it file

1. void EXTI0_IRQHandler(void)
2. {
3. EXTI_ClearITPendingBit(EXTI_Line0);
4.   if(EXTI_GetITStatus(EXTI_Line0) != RESET) // If i have inpulse
5.   {
6. i++;
7. EXTI_ClearITPendingBit(EXTI_Line0);
8. }
9. void EXTI1_IRQHandler(void)
10. {
11. EXTI_ClearITPendingBit(EXTI_Line1);
12.   if(EXTI_GetITStatus(EXTI_Line1) != RESET) // If i have inpulse
13.   {
14. j++;
15. EXTI_ClearITPendingBit(EXTI_Line1);
16. }