Question
STM32L151 Interrupt Problem
Posted on April 10, 2013 at 13:57
Hi,
I am using the STM32L151VB on a custom board. The MCU is clocked by HSI. I have two rising edge interrupts on port E pin 9 and port E pin I capture the timer counter for timer 4 in both the interrupts. The problem is that for each rising edge I am getting multiple interrupts and hence wrong values of timer 4 are captured. If I can ensure that only one interrupt per rising edge is generated it will solve my problem. Also my pulses have varying widths so using delay is not possible. Please advise. I have pasted my code below:void WS_Init_Wind_Sensors_Input()
{
GPIO_InitTypeDef gpio_init_structure;
EXTI_InitTypeDef exti_init ;
/* Enable GPIO clocks */
RCC_AHBPeriphClockCmd(WIND_SPEED_SENSOR_RCC_AHBPeriph | WIND_DIRECTION_SENSOR_RCC_AHBPeriph, ENABLE);
gpio_init_structure.GPIO_Pin = WIND_SPEED_SENSOR_GPIO_PIN;
gpio_init_structure.GPIO_Mode = GPIO_Mode_IN;
gpio_init_structure.GPIO_PuPd = GPIO_PuPd_NOPULL;
gpio_init_structure.GPIO_Speed = GPIO_Speed_40MHz;
gpio_init_structure.GPIO_OType = GPIO_OType_PP;
/* Initialise the GPIO accordingly */
GPIO_Init(WIND_SPEED_SENSOR_GPIO_PORT, &gpio_init_structure);
gpio_init_structure.GPIO_Pin = WIND_DIRECTION_SENSOR_GPIO_PIN;
/* Initialise the GPIO accordingly */
GPIO_Init(WIND_DIRECTION_SENSOR_GPIO_PORT, &gpio_init_structure);
/* The syscfg module is clocked */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
/* The EXTI mux is on exti line RG_EXTI_PINSOURCE for this GPIO pin */
SYSCFG_EXTILineConfig(WIND_SPEED_SENSOR_EXTI_PortSource,WIND_SPEED_SENSOR_EXTI_PinSource);
/* The EXTI mux is on exti line RG_EXTI_PINSOURCE for this GPIO pin */
SYSCFG_EXTILineConfig(WIND_DIRECTION_SENSOR_EXTI_PortSource,WIND_DIRECTION_SENSOR_EXTI_PinSource);
EXTI_StructInit(&exti_init);
exti_init.EXTI_Line = WIND_SPEED_SENSOR_EXTI_LINEx;
exti_init.EXTI_LineCmd = ENABLE;
exti_init.EXTI_Trigger = EXTI_Trigger_Rising;
EXTI_Init(&exti_init);
/*Enable the interrupt in the NVIC */
INIT_NVIC_Enable_Peripheral_Interrupt(WIND_SPEED_SENSOR_EXTIx_IRQn,0,0);
exti_init.EXTI_Line = WIND_DIRECTION_SENSOR_EXTI_LINEx;
exti_init.EXTI_Trigger = EXTI_Trigger_Rising;
EXTI_Init(&exti_init);
/*Enable the interrupt in the NVIC */
INIT_NVIC_Enable_Peripheral_Interrupt(WIND_DIRECTION_SENSOR_EXTIx_IRQn,2,2);
}
int td1x, ts1x, ts2x ;
/*!
Interrupt handler for pulse 1
*/
void EXTI9_5_IRQHandler(void)
{
INIT_NVIC_Disable_Peripheral_Interrupt(WIND_DIRECTION_SENSOR_EXTIx_IRQn,0,0);
EXTI->PR = EXTI_Line9 ;
/* This is being set multiple times for each rising edge since the interrupt is being re-entrant */
td1x = TIM4->CNT;
INIT_NVIC_Enable_Peripheral_Interrupt(WIND_DIRECTION_SENSOR_EXTIx_IRQn,0,0);
}
/*!
Interrupt handler for pulse 2
*/
void EXTI15_10_IRQHandler()
{
static int x = 1;
INIT_NVIC_Disable_Peripheral_Interrupt(WIND_SPEED_SENSOR_EXTIx_IRQn,0,0);
EXTI->PR = EXTI_Line10;
/* This is being set multiple times for each rising edge since the interrupt is being re-entrant */
x ^= 1;
if(x)
{
ts2x = TIM4->CNT;
}
else
{
ts1x = TIM4->CNT;
}
INIT_NVIC_Enable_Peripheral_Interrupt(WIND_SPEED_SENSOR_EXTIx_IRQn,0,0);
}