8255bu.txt

//下面是画圆的程序

#include<reg51.h>
#include<absacc.h>
#define mode8255 0x80
//#define com8255 XBYTE[0x8003]
//#define pa8255 XBYTE[0x8000]
 xdata unsigned char com8255 _at_ 0x8003;
xdata unsigned char pa8255 _at_ 0x8001;
void delay()
{
   unsigned char tt,cc;

   for(tt=50;tt>0;tt--)
      for(cc=124;cc>0;cc--);
}

void main()
{  unsigned char a;

   com8255= mode8255;
   while(1)
   {

      a=0x01;
      pa8255=a;
      delay();

      a=0x02;
      pa8255=a;
      delay();

      a=0x04;
      pa8255=a;
      delay();

      a=0x08;
      pa8255=a;
      delay();


   }

}