int main()
{
// 配置时钟GPIOF
*((volatile int *)(RCC_BASE + AHB1_OFFSET)) |= 0x00000020;
// 配置模式
*((volatile int *)(GPIOF_BASE + GPIOF_MODER_OFFSET)) |= 0x00040000;
*((volatile int *)(GPIOF_BASE + GPIOF_ODR_OFFSET)) |= 0x00000200;
while (1)
{
*((volatile int *)(GPIOF_BASE + GPIOF_ODR_OFFSET)) &= ~(0x00000200);
for (int i = 0; i < DELATY; i++)
;
*((volatile int *)(GPIOF_BASE + GPIOF_ODR_OFFSET)) |= 0x00000200;