程序看不是很懂 求能懂的大神注释下 或者教下  感激不尽 感激不尽


#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char
sbit key1=P1^1;    //信号
sbit key2=P1^2;    //布防
sbit key4=P1^5;    //报警
sbit r_led=P1^3;
sbit g_led=P1^0;
sbit speak=P1^4;
void delay(uint i)
{
    uchar j,k;
    for(j=0;j<i;j++)
        for(k=0;k<120;k++);
}
void main()
{
    uint i;
    speak=1;
    r_led=1;
    g_led=1;
    while(1)
    {
        if(key2==0){  //布防
            delay(5);
            {if(key2==0){
                  i=0;
                  while(key2==0);
                            }}
                        }
        if(key4==0){    //停止
            delay(5);
            {if(key4==0){
                  i=1;
                  while(key4==0);
                        }}
                    }
        if(i==1){
               speak=1;
            r_led=1;
            g_led=0;
                }
        if(i==0){
            if(key1==0){
                delay(5);
                if(key1==0){
                        speak=1;
                        r_led=0;
                        g_led=1;
                        delay(50);
                        r_led=1;
                        speak=0;
                        delay(50);
                           }
                        }
                }
        }     
}