try1.c

我认为很经典的供初学者学习的数码管显示程序

#include<reg51.h>
#include<stdio.h>

sbit P20=0xA0;
sbit P21=0xA1;
sbit P22=0xA2;
sbit P23=0xA3;

bit Change_Flag;
void Updata_LED();
xdata int nCounter=0;
xdata int nIndex=0;
xdata int nDataToDisplay=0;
char Table[10]={0X3F,0X06,0X5B,0X4F,0X66,0X6D,0X7D,0X07,0X7F,0X6F};
main()
{
SCON=0x52;
TMOD=0x21;
TCON=0x69;
TH1=0xf3;
TH0=0x3C;
TL0=0xAF;
ET0=1;
EA=1;
TF0=0;
TR0=1;
P2=0xFF;
Change_Flag=0;
nCounter=0;
while(1)
{
if (Change_Flag==1)
{
Updata_LED();
if(nDataToDisplay>9999) nDataToDisplay=0;
}
}
}

void Timer0_Overflow() interrupt 1 using 0
{
TH0=0x3C;
TL0=0xAF;
if (nCounter==20)
{
nCounter=0;
nDataToDisplay++;
Change_Flag=1;
}
nCounter++;
}
void Updata_LED	()
{
int nTemp;
nTemp=nDataToDisplay;
P20=1;
nIndex=nTemp%10;
P0=Table[nIndex];
P20=0;
nTemp/=10;
P21=1;
nIndex=nTemp%10;
P0=Table[nIndex];
P21=0;
nTemp/=10;
P22=1;
nIndex=nTemp%10;
P0=Table[nIndex];
P22=0;
nTemp/=10;
P23=1;
nIndex=nTemp%10;
P0=Table[nIndex];
P23=0;
Change_Flag=0;
}