一，用矩阵键盘操作原理图（仿真）

2.主程序（源代码）

#include<reg51.H>//#include<stdio.h>#define LEDS 8/***°´¼ü³ÌÐò***/char keyscan();/***ÏÔʾ³ÌÐò***/	void display();char dsp[9]={0,0,12,12,12,12,12,12,12};	//³õʼ»¯ÏÔʾÊý×é/***¼ÆËã³ÌÐò***/	void calculate(char k,char c1[8],char c2[8]);	/***Ƭѡ***/unsigned char code Select[]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80};/***ÂëÑ¡***/	unsigned char code LED_CODES[]=				{0xC0,0xF9,0xA4,0xB0,0x99,	//0-40x92,0x82,0xF8,0x80,0x90,	//5-90x86,0xAF,0xFF,0x7F,0xBF,};	//E,r,¿Õ¸ñ,.,-/***mainº¯Êý***/void main(void){char i,j,k,c;char a[8],b[8];/***¶¨Ê±1ms***/TMOD=0;TL0=-(1000/256);TH0=-(1000%256);EA = 1; //×ÜÖжϿª¹ØET0 = 1; //¿ªÖжÏTR0 = 1; //ÆôÓüÆÊýÆ÷0KSC:do	{	for(i=1;i<9;i++)	//Êý×Ö¼ÈëÑ­»·		{		dsp[0]=keyscan();		if(c==2&&dsp[0]<10)		//´Ë¶Î´úÂëÑéÖ¤ÊÇ·ñÓоɵļÆËã½á¹ûÔÚÏÔʾ£¬ÇÒ²»ÔÙ²ÎÓëмÆËã			{			dsp[1]=dsp[0];			for(j=2;j<9;j++)			dsp[j]=12;			c=0;			}		else if(c==2&&dsp[0]>9)		//¾ÉµÄ¼ÆËã½á¹û½«²ÎÓëеļÆË㣬×÷ΪµÚÒ»¸öÊý			{			c=0;			}						if(dsp[0]==0&&dsp[1]==0&&dsp[2]==12)	//¸öλΪ0ÇÒʮλΪ¿Õʱ°´ÏÂ0,°´¼üÎÞЧ£¬Ìø»ØKSCµÈ´ýÕýÈ·ÊäÈë			{			/***gotoÌøת±êÖ¾***/				goto KSC;			}		else if(dsp[0]>9) break;	//ÓвÙ×÷·û°´Ï£¬Ìø³öÊý×Ö¼ÈëÑ­»·					else			{for(j=i;j>0;j--)			dsp[j]=dsp[j-1];	//ÒÆ룬ÒÔÕýÈ·ÏÔʾÊý×Ö			}					}			if(i==9)	//ÅжÏÊÇ·ñÊäÈë8¸öÓÐЧÊý×Ö£¬ÊÇÔòµÈ´ý²Ù×÷·û£¬·ñÔòÖ±½ÓÅжϲÙ×÷·û		{		do	//ʹÓÃdo whileÎÞÂÛÊÇ·ñµÚÒ»¸öÊý¶¼È¡Ò»´Î²Ù×÷·û			{			dsp[0]=keyscan();	//»ñÈ¡²Ù×÷·ûºÅ			if(dsp[0]==14||dsp[0]<10)	//°´ÏÂC»òÕßµÚ9λÊý×ÖÇåÁã				{				dsp[1]=0;				for(i=2;i<9;i++)				dsp[i]=12;				c=0;				}			}while((dsp[0]==15)&&(c==0));		//µÈºÅ±»°´Ï£¬µÈ´ýеIJÙ×÷·û£¨½ö¶ÔµÚÒ»¸öÊý×ÖÓÐЧ£©		}	else if(dsp[0]==14)	//°´ÏÂCÇåÁã		{		dsp[1]=0;		for(i=2;i<9;i++)		dsp[i]=12;		c=0;		}		while(dsp[0]==15&&c==0)		//δÊäÂú8λÇÒÊǵÚÒ»¸öÊý×Ö¼´°´ÏµȺţ¬µÈ´ý·ÇµÈºÅ²Ù×÷·û		{		dsp[0]=keyscan();	//»ñÈ¡²Ù×÷·ûºÅ		if(dsp[0]==14||dsp[0]<10)	//°´ÏÂC»òÕßÊý×Ö¶¼½øÐÐÇåÁã,ÖØÐÂÊäÈëa			{			dsp[0]=14;	//½«dsp[0]ÖÃΪ14£¬·ÀÖ¹ÒòÊý×ÖÇåÁãδÄÜÀ¹½Ø			dsp[1]=0;			for(i=2;i<9;i++)			dsp[i]=12;			c=0;			}				}	}while(dsp[0]==14);		//Êý×ÖÊäÈëδÍê³É¼´°´ÏÂC£¬ÖØеȴýÊäÈë	do	{		if(c==0)	//ûÓÐÊý×ÖÊäÈë		{ 			k=dsp[0];	//´æ¼ÆËã·û£¨Ñ­»·ÄÚÒÑÅųýC¡¢£½¡¢Êý×Ö£©		for(i=0;i<8;i++)	//½«µÚÒ»¸öÊý´æÈëa[8]			{			a[i]=dsp[i+1];			}					dsp[1]=0;	//ÇåÁã		for(i=2;i<9;i++)		dsp[i]=12;				c=1;	//ÒÑÊäÈëa		/***gotoÌøת±êÖ¾***/		goto KSC;		}	else if(c==1)		{				for(i=0;i<8;i++)	//½«µÚ¶þ¸öÊý´æÈëb[8]			{			b[i]=dsp[i+1];			}			c=2;	//ÒÑÊäÈëb			if(dsp[0]!=15)	//bÊäÍêºó²Ù×÷·û²»ÊǵȺÅ			{			calculate(k,a,b);			for(i=0;i<8;i++)	//½«¼ÆËã½á¹û´æÈëa[8]£¬aÖµ¸üÐÂ				{				a[i]=dsp[i+1];				}			k=dsp[0];	//¸üмÆËã·û			c=1;			/***gotoÌøת±êÖ¾***/			goto KSC;			}		}	}while((dsp[0]==15)&&(c<2));	//Ö±µ½abÊäÈëÍê³ÉÇÒ°´ÏµȺÅcalculate(k,a,b);	//½øÐÐ×îºó¼ÆËã/***gotoÌøת±êÖ¾***/goto KSC;	//Ìø»ØKSC£¬µÈ´ýÐÂÒ»ÂÖ¼ÆËãwhile(1);	//·ÀÖ¹³ÌÐòÅÜ·É}char keyscan(){char KeyL;char KeyR;char j;do	{	do		{		P3=0xF0;		P3=P3|0xF0;//ÐÐɨÃè11110000				if(P3!=0xF0)			{			KeyL=P3;			P3=0x0F;			P3=P3|0x0F;//ÁÐɨÃè00001111			KeyR=P3;			}		}while(KeyL==0xF0||KeyR==0x0F);		for(j=0;j<12;j++)		//ÑÓʱ0.001s=1ms		{;}	}while(P3!=0x0F); switch(KeyL&KeyR)	{	case 0x28:{return 0;break;}	case 0x11:{return 1;break;}	case 0x21:{return 2;break;}	case 0x41:{return 3;break;}	case 0x12:{return 4;break;}	case 0x22:{return 5;break;}	case 0x42:{return 6;break;}	case 0x14:{return 7;break;}	case 0x24:{return 8;break;}	case 0x44:{return 9;break;}	case 0x81:{return 10;break;}//¼Ó·¨(µÚÒ»ÐУ¬µÚËÄÁÐ)	case 0x82:{return 11;break;}//¼õ·¨£¨µÚ¶þÐУ¬µÚËÄÁУ©	case 0x84:{return 12;break;}//³Ë·¨£¨µÚÈýÐУ¬µÚËÄÁУ©	case 0x88:{return 13;break;}//³ý·¨£¨µÚËÄÐУ¬µÚËÄÁУ©	case 0x18:{return 14;break;}//ÇåÁ㣨µÚËÄÐУ¬µÚÒ»ÁУ©	case 0x48:{return 15;break;}//¼ÆËã½á¹û£¨µÚËÄÐУ¬µÚÈýÁУ©	}}void display() interrupt 1 using 1	//ÀûÓö¨Ê±Æ÷ÖжÏʵÏÖ¼äʱÏÔʾ		{char i,j,h;ET0=0;for(j=8;j>0;j--)	//ɨÃè8´Î	{	for(i=7;i>=0;i--)	//´Ó¸ßλµ½µÍλɨÃèÏÔʾ		{		P2=0;		P1=LED_CODES[dsp[8-i]];		P2=Select[i];		for(h=0;h<8;h++)		{;}		}	}TL0=-(1000/256);TH0=-(1000%256);ET0=1;	}void calculate(char k,char a[8],char b[8]){char r[8];long i,x,y;i=0;x=0;y=0;for(i=7;i>0;i--)	//Êýֵת»¯£¬½«´ú±í¿Õ¸ñµÄ12ת»¯ÎªÊý×Ö0£¬ÒòΪ¸öλ²»ÏÔʾ¿Õ¸ñ£¬Ä¬ÈÏΪ0£¬ËùÒÔ²»×ª»¯	{	while(a[i]==12)a[i]=0;	while(b[i]==12)b[i]=0;	}x=a[4];x=10000*x;x=x+a[0]+a[1]*10+a[2]*100+a[3]*1000+a[5]*100000+a[6]*1000000+a[7]*10000000;y=b[4];y=10000*y;y=y+b[0]+b[1]*10+b[2]*100+b[3]*1000+b[5]*100000+b[6]*1000000+b[7]*10000000;if(k==10)//¼Ó·¨ÔËËã	{	x=x+y;	if(x>99999999)	//´óÓÚ8룬ÏÔʾ¡°Err¡±		{		r[0]=11;	//r		r[1]=11;	//r		r[2]=10;	//E		r[3]=12;	//¿Õ¸ñ		r[4]=12;		r[5]=12;		r[6]=12;		r[7]=12;		}	else		{		r[0]=x%10;		r[1]=(x%100)/10;		r[2]=(x%1000)/100;			r[3]=(x%10000)/1000;		r[4]=(x%100000)/10000;		r[5]=(x%1000000)/100000;		r[6]=(x%10000000)/1000000;		r[7]=x/10000000;		}	}if(k==11)//¼õ·¨ÔËËã	{			if(x<y)		{		x=y-x;		if(x>9999999)			{			r[0]=11;	//r			r[1]=11;	//r			r[2]=10;	//E			r[3]=12;	//¿Õ¸ñ			r[4]=12;			r[5]=12;			r[6]=12;			r[7]=12;			}		else			{			r[0]=x%10;			r[1]=(x%100)/10;			r[2]=(x%1000)/100;				r[3]=(x%10000)/1000;			r[4]=(x%100000)/10000;			r[5]=(x%1000000)/100000;			r[6]=(x%10000000)/1000000;			r[7]=x/10000000;						for(i=7;i>0;i--)	//½«ÓÐЧÊý×ֵĸßһλת»¯Îª£­ºÅ				{				if(r[i]==0&&r[i-1]!=0)					{					r[i]=14;					break;					}				}			}		}	else		{		x=x-y;		r[0]=x%10;		r[1]=(x%100)/10;		r[2]=(x%1000)/100;			r[3]=(x%10000)/1000;		r[4]=(x%100000)/10000;		r[5]=(x%1000000)/100000;		r[6]=(x%10000000)/1000000;		r[7]=x/10000000;		}		}if(k==12)//³Ë·¨ÔËËã	{	i=x;	x=x*y;	if(y==0)		{		x=0;		}	else if(x>99999999||x<i)	//»ý´óÓÚ99999999»òÕßСÓÚ³ËÊý¶¼ÈÏΪÊÇÒì³£,´æÔÚÆäËû¿ÉÄܵÄÒç³ö£¬Ðë×ÔÐбæ±ð		{		r[0]=11;	//r		r[1]=11;	//r		r[2]=10;	//E		r[3]=12;	//¿Õ¸ñ		r[4]=12;		r[5]=12;		r[6]=12;		r[7]=12;		}	else		{		r[0]=x%10;		r[1]=(x%100)/10;		r[2]=(x%1000)/100;			r[3]=(x%10000)/1000;		r[4]=(x%100000)/10000;		r[5]=(x%1000000)/100000;		r[6]=(x%10000000)/1000000;		r[7]=x/10000000;		}	}if(k==13)//³ý·¨ÔËËã	{		if(y==0)	//±»³ýÊý²»ÄÜΪ0		{		r[0]=11;	//r		r[1]=11;	//r		r[2]=10;	//E		r[3]=12;	//¿Õ¸ñ		r[4]=12;		r[5]=12;		r[6]=12;		r[7]=12;		}	else		{		x=x/y;		r[0]=x%10;		r[1]=(x%100)/10;		r[2]=(x%1000)/100;			r[3]=(x%10000)/1000;		r[4]=(x%100000)/10000;		r[5]=(x%1000000)/100000;		r[6]=(x%10000000)/1000000;		r[7]=x/10000000;		}	}for(i=7;i>0;i--)	//Êýֵת»¯,½«¸ßλµÄÎÞЧÊý×Ö0ת»¯Îª¿Õ¸ñ·û12	{	if(r[i]==0)		r[i]=12;		 else 		 	break;	}for(i=0;i<8;i++)	//½«¼ÆËã½á¹û´æÈëdsp[9]£¬ÏÔʾÊý¸üÐÂ	{	dsp[i+1]=r[i];	}}

输入2+3

输入2

输入3

结果