ST STM32F31xx User Manual

UM1581
How to use and customize the library
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2.6.4 main.c
The main.c file calls the library driver functions to configure the EXTI, GPIO and NIVC
peripherals.
Include the library and STM32303C-EVAL-EVAL board resources:
/* Includes -----------------------------------------------------*/
#include "stm32f30x.h" /* The Library entry point */
#include "stm32303C_eval" /* Needed when using STM32303C-EVAL
board*/
Declare three structure variables, used to initialize the EXTI, GPIO and NIVC peripherals:
/* Private typedef ----------------------------------------------*/
EXTI_InitTypeDef EXTI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
Declare prototype for a local function:
/* Private function prototypes ----------------------------------*/
void Delay(__IO uint32_t nCount);
The main program will be structured as follow:
/**
* @brief Main program.
* @param None
* @retval None
*/
int main(void)
{
1. System clock configuration:
/*!< At this stage the microcontroller clock setting is already
configured,
this is done through SystemInit() function which is called from
startup
file (startup_stm32f30x.s) before to branch to application
main.
To reconfigure the default setting of SystemInit() function,
refer to
system_stm32f30x.c file */
2. Enable the clock for the peripheral(s) to be used (EXTI interface clock is always
enabled):
/* Enable GPIOA's AHB interface clock */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
/* Enable SYSCFG's APB interface clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
3. Configure the peripheral GPIOs:
/* Connect EXTI6 Line to PE6 pin */
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOE, EXTI_PinSource6);
/* Configure PE6 pin in input mode */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;

ST STM32F31xx Specifications

General

Brand	ST
Model	STM32F31xx
Category	Microcontrollers
Language	English