chenmiaoyan的博客

#include <stdio.h>#include <stm32f4xx.h>void show(void){ int a,b; for(a=2000;a>0;a--) for(b=1200;b>0;b--);}int main(void){ GPIO_InitTypeDef GPIO_InitStructure; //使能GPIOF组引脚的时钟 RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOF,ENA