51单片机学习笔记:写了个led宏,并尝试控制led灯的亮度
//#include "my51.h"#include <reg52.h>typedef unsigned char u8;typedef unsigned short int u16;#ifndef _51LED_#define _51LED_#define led P1 //P1总线连8个led灯,灯连573锁存器,P1置低电平点亮#define LED led#define ON(x) P1&(~(1<<(x))) //打开某个灯,开多个灯用 ON(m) & ON(n)#define OFF(x) P1|(1<<(x)) //关闭某个灯,关多个灯用 OFF(m)| OFF(n)#define on(x) ON(x) //包含大小写#define off(x) OFF(x)#define ledon 0 //某个灯,打开#define ledoff 1 //某个灯,关闭sbit led0=P1^0; sbit led1=P1^1;sbit led2=P1^2;sbit led3=P1^3;sbit led4=P1^4;sbit led5=P1^5;sbit led6=P1^6;sbit led7=P1^7;sbit ledLock=P2^5;//锁定当前8个led的状态,0锁定 ,1不锁定#endifvoid ledCtr(u8 ledX,u8 per)//参数1是某个灯,参数2是亮度{u8 i=1;for(i=1;i<=100;i++){if(i<per){led=on(ledX) ;//打开灯}else{led=off(ledX);//关闭灯}}}void delayms(u16 ms) //毫秒级软延时函数{u16 i,j;for(i=ms;i>0;i--){ for(j=113;j>0;j--) {}}}void main() //测试{led6=ledon; //打开6号灯,亮度100%led=on(0);//打开0号灯,亮度100%led=on(1) & on(5); //打开1号和5号灯,亮度100% delayms(2000);led0=ledoff; //关闭0号灯led=off(6)|off(1)|off(5);//关闭1,5,6号灯while(1){ ledCtr(2,5); //仅打开2号灯,亮度5%, 省电...}}
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