km2.c

刚才那个是个完整的综合设计单片机程序

//在P1口接一个共阴的数码管，要求在其上面循环显示“9~~0”的数字。
//P1.7为位选信号
#include<at89x52.h>
unsigned char disbuf[2];
displaybrush()
{unsigned char code seg7code[10]={0xbf,0xb0,0xdb,0xcf,0xe6,
                                  0xed,0xfd,0x87,0xff,0xef};
P1=seg7code[disbuf[0]];
P1_7=0;
}
display()
{static unsigned char k=9;
disbuf[0]=k;
k=k-1;
if(k==255)k=9;
return(k);}
void delay(unsigned char x)
{unsigned char i,j;
 for(i=0;i<x;i++)
 for(j=0;j<255;j++);}
main()
{while(1)
 {displaybrush();
  delay(1); 
  display();
 }
}