[嵌入式]51单片机入门（在1602上做个时钟）

#include <reg52.h>
#define uint unsigned int
#define uchar unsigned char
uchar code table[]="  2022-1-12 WED";
uchar code table1[]="    00:00:00";
sbit dula=P2^6;
sbit wela=P2^7;
sbit lcden=P3^4;  //液晶 LCDEN端
sbit lcdrs=P3^5;  //液晶 RS端
sbit s1=P3^0;    //定义按键-功能键
sbit s2=P3^1;    //定义按键-增大键
sbit s3=P3^2;    //定义按键-减小键
sbit rd=P3^7;    
uchar count,s1num;
char shi,fen,miao;
void delay (uint z)  //延时函数
{
		uint x,y;
		for(x=z;x>0;x--)
				for(y=110;y>0;y--);
}
void write_com(uchar com)  //液晶写命令函数
{
		lcdrs=0;
		P0=com;
		delay(5);
		lcden=1;
		delay(5);
		lcden=0;
}
void write_date(uchar date)  //液晶写数据函数
{
		lcdrs=1;
		P0=date;
		delay(5);
		lcden=1;
		delay(5);
		lcden=0;
}
void inti()   //初始化函数
{
		uchar sum;
//		shi=23;
//		fen=59;
//		miao=53;
	    dula=0;	
		wela=0;
		lcden=0;
		TMOD=0x01;
		TH0=(65536-50000)/256;
		TL0=(65536-50000)%256;
		EA=1;
		ET0=1;
		TR0=1;
		write_com(0x38);
		write_com(0x0c);
	    write_com(0x06);
		write_com(0x01);
		write_com(0x80);    //液晶第一行的地址
		for(sum=0;sum<15;sum++)
		{
				write_date(table[sum]);   //将字符写入液晶
				delay(5);
		}
		write_com(0x80+0x40);  //液晶第二行的地址
		for(sum=0;sum<12;sum++)  
		{
				write_date(table1[sum]);
				delay(5);
		}
		
}

void write_sfm(uchar add,uchar date)  //液晶扫描函数
{
		uchar shi,ge;
		shi=date/10;
		ge=date%10;
		write_com(0x80+0x40+add);  //地址
		write_date(0x30+shi);   //个位的数据
		write_date(0x30+ge); 
		
}
void key()   //键盘检测函数
{
		rd=0;
		if(s1==0)
		{
				delay(5);  //防抖
				if(s1==0)  //防误触
				{
						s1num++;
						while(!s1);
						switch(s1num)
						{
							case 1:        //第一次按下功能键
									TR0=0;  //定时器关闭
									write_com(0x80+0x40+11);  //光标指向秒的个位
									write_com(0x0f);    //打开光标
									break;
							case 2:
									TR0=0;
									write_com(0x80+0x40+8);
									write_com(0x0f);
									break;
							case 3:
									TR0=0;
									write_com(0x80+0x40+5);
									write_com(0x0f);
									break;
							case 4:
									s1num=0;								
									write_com(0x0c);  //关闭光标
									TR0=1;  //定时器开始
									break; 
						}
				}
				
		}
		if(s1num!=0)
		    {
						if(s2==0)
						{
								delay(5);
								if(s2==0)
								{
										while(!s2);
										switch(s1num)
										{
												case 1:
														miao++;
														if(miao==60)
														{
																miao=0;
														}
														write_sfm(10,miao); //秒写入液晶     
														write_com(0x80+0x40+11);
														break;
												case 2:
														fen++;
														if(fen==60)
														{
																fen=0;
														}
														write_sfm(7,fen);
														write_com(0x80+0x40+8);
														break;
												case 3:
														shi++;
														if(shi==24)
														{
																miao=0;
														}
														write_sfm(4,shi);
														write_com(0x80+0x40+5);
														break;
													
													
										}
								}
						}
						if(s3==0)
						{
								delay(5);
								if(s3==0)
								{
										while(!s3);
										switch(s1num)
										{
												case 1:
														miao--;
														if(miao==-1)
														{
																miao=59;
														}
														write_sfm(10,miao);
														write_com(0x80+0x40+11);
														break;
												case 2:
														fen--;
														if(fen==-1)
														{
																fen=59;
														}
														write_sfm(7,fen);
														write_com(0x80+0x40+8);
														break;
												case 3:
														shi--;
														if(shi==-1)
														{
																shi=23;
														}
														write_sfm(4,shi);
														write_com(0x80+0x40+5);
														break;
													
													
										}
								}
						}
		    }
		
		
}
void main()
{
		inti();
		while(1)
		{
				key();
				if(count==20)
				{
						count=0;
						miao++;
						if(miao==60)
						{
								miao=0;
								fen++;
								if(fen==60)
								{
										fen=0;
										shi++;
										if(shi==24)
										{
												shi=0;
										}write_sfm(4,shi);
								}write_sfm(7,fen);
						}write_sfm(10,miao);
				}
			}
}

void time_0() interrupt 1  //定时器中断函数
{
		TH0=(65536-50000)/256;
		TL0=(65536-50000)%256;
		count++;
}