Posted on August 14, 2015 at 11:17Hello,
Kindly guide me to resolve this.
I have a board having STM32F429 on it. while adding new requirements in the board, a situation has arised such that i am left with no option other than to use port pin PA15 for External Interrupt. PA15 default function is for JTAG.
I tried following code to init port PA15 to use as External Interrupt but i observed that after running the code, Voltage level on port pin remain high (3.3V).
I tested the circuit after disconnecting from the port pin, Found, that circuit works fine. It toggles between 3.3V and 0V, if the input to circuit toggles.
But as i connect it to port pin, it remains high and does not toggle as expected.
The init code is as follows. Please guide me where i have done mistake.
void EXTILine15_Config(void)
{
EXTI_InitTypeDef EXTI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable GPIOA clock */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
/* Enable SYSCFG clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_15;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Connect EXTI Line15 to PA15 pin */
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource15);
/* Configure EXTI Line15 */
EXTI_InitStructure.EXTI_Line = EXTI_Line15;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
/* Enable and set EXTI Line15 Interrupt to the lowest priority */
NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
I want port pin PA15 to work as External interrupt.
thanks.
#stm32f4 #external-interrupt #jtag
