#include <stm32f407xx.h>

int main(void)
{

        RCC->AHB1ENR |= RCC_AHB1ENR_GPIODEN;
        GPIOD->MODER |= GPIO_MODER_MODE0_0;
        GPIOD->OSPEEDR |= (GPIO_OSPEEDR_OSPEED0);
        GPIOD->OTYPER &= ~(GPIO_OTYPER_OT0);
        GPIOD->PUPDR &= ~(GPIO_PUPDR_PUPD0);

        GPIOD->ODR = 1;
        while (1) {

        }
}