volatile unsigned int *P_IOA_Data=(unsigned int*)(0x7000); 	volatile unsigned int *P_IOA_Dir=(unsigned int*)(0x7002);volatile unsigned int *P_P_IOA_Attrib=(unsigned int*)(0x7003);unsigned int old,new,push,rel,temp,row;void key(void){	for(row=0x10;row<0x100;row=row<<1)	{		*P_IOA_Data=*P_IOA_Data&row;		new=(new<<4)| *P_IOA_Data&0x0f;	}	if((temp=new^old)>0)	{		push=temp&new;		rel=temp&old;		old=new;	}}///////////////////////////////////////main(){	*P_IOA_Dir=0x00f0;	*P_P_IOA_Attrib=0;	*P_IOA_Data=0x000f;	key();}