51

来自「计算机控制系统」· 代码 · 共 27 行

#include    <reg51.h>
#include    <absacc.h>
#define		con0	XBYTE[0xcfa0]
#define		con1	XBYTE[0xcfa1]
unsigned int addr;
void ext0(void) interrupt 0
  {
   EA = 0;
   addr = con0;
   addr = (con0-0x80)/4;
   if((P1>>addr)&1) P1 &= (~(1<<addr));
   else P1 |= (1<<addr);
   con0 = 0x20;
   EA = 1;
  }

void main(void)
  {
   con0 = 0x96;
   con1 = 0x40;
   P1 = 0xff;
   IT0 = 0;
   EX0 = 1;
   EA = 1;
   while(1);
  }