89C51单片机实现1位整数的加法运算，结果只需显示整数。按等于号切换显示结果。

#include <reg51.h>
#include "intrins.h"
#define LBIT P0     
#define LNUM P2    
#define IO_KEY P1   
unsigned char code ledTab[]={0x3F,0x06,0x5B,0x4F,
	                           0x66,0X6D,0X7D,0X07,
	                           0X7F,0X6F,0X77,0X6d,
                             0x76,0x3f,0x79,0x71,
                             0x76,0x73,0x38,0x3e,0x00};
unsigned char code tabIndex[]={0xfe,0xFD,0xFB,0xF7,0xEF,0xDF,0xBF,0x7F};
unsigned char Num[8]={20,20,20,20,20,20,20,20};

void Delay_us(unsigned int time)
{
	while(time--);
}
void dynamicLed(unsigned char Counter,unsigned char Ligh)
{
	unsigned char i;
	for(i=0;i<Counter;i++)
	{
		LBIT=tabIndex[i%8];
		LNUM=ledTab[Num[i]%21];
		Delay_us(Ligh);
		LNUM=0x00;
	}
}
unsigned char scanKey()
{
unsigned char temp,tempCode,i=0;
unsigned char LastCode=0;
tempCode=0x00;
IO_KEY=0x0F;
temp=IO_KEY;
if((temp&0x0F)!=0x0F)
{
	Delay_us(200);
	
  temp=0xF7;
  while(i<4)
		{
			temp=_crol_(temp,1);
      IO_KEY=temp;
      tempCode=IO_KEY&0x0f;
			if(tempCode!=0x0F)
				{
					switch(tempCode)
						{
							case 0x0E:
			        LastCode=LastCode+0;
		          break;
		          case 0x0D:
			        LastCode=LastCode+1;
		          break;
		          case 0x0B:
			        LastCode=LastCode+2;
		          break;
		          case 0x07:
			        LastCode=LastCode+3;
		          break;
		          default:
			        LastCode=LastCode+0;
		          break;
						}
						IO_KEY=0x0F;
						temp=IO_KEY;
						while((temp&0x0F)!=0x0F)
							{
								IO_KEY=0x0F;
								temp=IO_KEY;
	            }
							break;
				}
				i++;
				LastCode+=4;
		}
}
else
	LastCode=16;
  return LastCode;         
}
void main(void)
{
	unsigned char tempkey,i;
	while(1)
	{
		tempkey=scanKey();
		if(tempkey!=16)      
		{
			for(i=7;i>0;i--)
			{
				Num[i]=Num[i-1];
			}
			Num[0]=tempkey;
		}
	
		dynamicLed(8,10);
	}
}

代码目前能实现的就是输入键值从右往左显示，然后不知道要怎么进行加法运算，我现在键盘可以输入0-9还有加减乘除的符号，想问问看后面加法要怎么改

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• 文章：89C51单片机按键控制数码管静态显示0~9 中也许有你想要的答案，请看下吧

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