#include <stdint.h> 
#include <stdlib.h> 
//Registradores RCC 
#define BASE_ADDRESS_RCC 0x40021000UL 
#define RCC_IOPENR_OFFSET 0x34UL 
#define RCC_IOPENR (*(volatile unsigned int *) (BASE_ADDRESS_RCC + RCC_IOPENR_OFFSET)) 
//Registradores GPIO 
#define BASE_ADDRESS_GPIOA 0x50000000UL 
#define GPIOA_MODER_OFFSET 0x00UL 
#define GPIOA_MODER (*(volatile unsigned int *) (BASE_ADDRESS_GPIOA + GPIOA_MODER_OFFSET)) 
#define GPIOA_ODR_OFFSET 0x14UL 
#define GPIOA_ODR (*(volatile unsigned int *) (BASE_ADDRESS_GPIOA + GPIOA_ODR_OFFSET)) 
//Mapeamento de Hardware 
#define enableGPIOA (1U<<0) 
#define pinoLed (1U<<5) 

int main() { 
uint32_t i; 
RCC_IOPENR |= enableGPIOA; //Habilitando o clock para o periférico 
GPIOA_MODER |= (1U<<10);  //PAS como saída 
GPIOA_MODER &= ~(1U<<11); //PAS como saída 
GPIOA_ODR |= pinoLed; //User led (LD4) inicià aceso 

while(1) { 

for(i=0;i<10000;i++) 
{ 

} 

GPIOA_ODR ^= pinoLed; 
} 
}