Posted on January 27, 2014 at 17:31I've got the example working using the on board button and now I want to use an external button on CPIOC - 11. I've used this button with GPIO_ReadInputDataBit with PuPd_UP. I've converted over the sample code but I've not getting any interrupt. I thought that the EXTI_Line needs to also be 11 and the EXTILineConfig with GPIOC and PinSource11 but I'm confused with the EXTI Line number and NVIC IRQChannel as it seems there are 5 of them.
Thanks,
Jim.
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable GPIOA clock */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
/* Enable SYSCFG clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
/* Configure PA0 pin as input floating */
GPIO_StructInit(&GPIO_InitStructure); // Reset init structure
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_Init(GPIOC, &GPIO_InitStructure);
/* Connect EXTI Line0 to PA0 pin */
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOC, EXTI_PinSource11);
/* Configure EXTI Line0 */
EXTI_InitStructure.EXTI_Line = EXTI_Line11;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising_Falling;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
/* Enable and set EXTI Line0 Interrupt to the lowest priority */
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x01;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
#stm32f4discovery-exti-nvic-setup
