原理圖：

實現程式碼

light.h

#ifndef __LIGHT_H
#define __LIGHT_H 			   
#include <sys.h>	

#define LED1 PDout(0)
#define LED2 PDout(1)
#define LED3 PDout(3)




void LED_init(void);

#endif

light.c

#include "sys.h"
#include "light.h"

void LED_init()
{
	GPIO_InitTypeDef  GPIO_InitStructure;
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);//´ò¿ªÊ±ÖÓ
	
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_3;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;//Êä³ö¹¦ÄÜ
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//ÍÆÍìÊäÈë
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//ÉÏÀ­
	
	
  GPIO_Init(GPIOD, &GPIO_InitStructure);//³õʼ»¯D¶Ë¿Ú
}
 

main.c

#include "stm32f4xx.h"
#include "usart.h"
#include "delay.h"

#include "light.h"

int main(void)
{
	delay_init(168);
	LED_init();
	
	LED1 = 0;
	LED2 = 1;
	LED3 = 0;
	
	while(1)
	{
		LED1 = ~LED1;
		LED2 = ~LED2;
		LED3 = ~LED3;
		delay_ms(1000);
	}
	
	return 0;
}

效果LED1和LED3同步每個1秒閃爍，同時LED2交替閃爍（LED在液晶屏右下方）

github原始碼下載