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《基于51单片机的计数器》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。
1、/*名称：外部计数+显示程序*//*功能：单片机外部输入脉冲信号，定时器参与计数*//*计数值由数码管显示出来。*//*****************************************************************/#include#defineucharunsignedcharsbitaddr0=P1^4;//系统片选地址线0sbitaddr1=P1^5;//系统片选地址线1sbitaddr2=P1^6;//系统片选地址线2sbitaddr3=P1^7;//系统片选地址线3/
2、/行扫描数组ucharcodescan[8]={0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f};//row0--row7//数码管显示的段码表ucharcodetable[18]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,//0,1,2,3,4,50x82,0xf8,0x80,0x90,0x88,0x83,//6,7,8,9,a,b0xc6,0xa1,0x86,0x8e,0xbf,0xff};//c,d,e,f,-,空格uchardispbuf[8];//显示缓冲区unsig
3、nedintcount;/*****************************延时函数**************************/voiddelay(unsignedintus){while(us--);}voidinitial(){ucharj;count=0;//秒清零for(j=0;j<6;j++)dispbuf[j]=0;//清数码管显示缓冲区TMOD=0x05;//T0T1工作于方式1TL0=0xff;TH0=0xff;//50ms定时初值ET0=1;//允许T1中断locatedintheTomb,D
4、ongShenJiabang,deferthenextdayfocusedontheassassination.Linping,Zhejiang,1ofwhichliquorwinemasters(WuzhensaidinformationisCarpenter),whogotAfewbayonets,duetomissedfatal,whennightcamePT0=1;//T1中断优先级高EA=1;//开中断TR0=1;//T1开始计时}/*************************************填充显示缓冲
5、区****************************/voidfeedbuffer(){unsignedinttemp;temp=count;dispbuf[5]=temp%10;//分个位temp=temp/10;dispbuf[4]=temp%10;//分十位temp=temp/10;dispbuf[3]=temp%10;//时百位temp=temp/10;dispbuf[2]=temp%10;//时千位temp=temp/10;dispbuf[1]=temp%10;//时万位temp=temp/10;dispbuf[
6、0]=temp%10;//时十万位}/******************************显示+读键*************************/voidvLedKey_Scan(){unsignedchari,value;for(i=0;i<8;i++){addr3=0;addr0=0;addr1=1;addr2=0;//开发板上U4（74HC574）的片选地址locatedintheTomb,DongShenJiabang,deferthenextdayfocusedontheassassination.Lin
7、ping,Zhejiang,1ofwhichliquorwinemasters(WuzhensaidinformationisCarpenter),whogotAfewbayonets,duetomissedfatal,whennightcamevalue=table[dispbuf[i]];//取一行显示数据P0=value;addr3=1;addr3=0;//在U4的11脚（锁存信号）产生上升沿P2=scan[i];//取row0--row7行扫描数据delay(50);//延时50usP2=0xff;//关显示}}/***
8、****************************主函数***********************/main(){initial();while(1){vLedKey_Scan();//显示，读键扫描}}//计数中断服务voidint50ms()int
