Controling digital circuit through computer..ltp port 4pins(C-h/w interaction)

#include
#include
#include
#include
#include
#include
#define port 0x0378

char ch;
void display(int,int,int,int);
void dispbutton(int);
void click(int,int,int,int);
void status(int,int,int,int);
void reset(int*,int*,int*,int*);

int x,y,button;
union REGS i,o;

initmouse()
{
i.x.ax=0;
int86(0x33,&i,&o);
return(o.x.ax);
}

void showmouseptr()
{
i.x.ax=1;
int86(0x33,&i,&o);
}

void getmousepos(int *button, int *x,int *y)
{
i.x.ax =3;
int86(0x33,&i,&o);
*button =o.x.bx;
*x=o.x.cx;
*y=o.x.dx;
}

void hidemouseptr()
{
i.x.ax=2;
int86(0x33,&i,&o);
}


void main()
{clrscr();
int s1=0,s2=0,s3=0,s4=0;
int gdriver=DETECT,gmode,ercode;
initgraph(&gdriver,&gmode,"");
ercode=graphresult();
if(ercode!=0){printf("error code:%s",grapherrormsg(ercode));
getch();}
display(s1,s2,s3,s4);
initmouse();showmouseptr();
while(ch!=27)
{getmousepos(&button,&x,&y);
if(button==1)
{if(x>80&&x<180&&y>100&&y<140)ch='1';
if(x>200&&x<300&&y>100&&y<140)ch='2';
if(x>320&&x<420&&y>100&&y<140)ch='3';
if(x>440&&x<540&&y>100&&y<140)ch='4';
if(x>440&&x<540&&y>300&&y<340)ch=32;
if(x>80&&x<180&&y>300&&y<340)ch=27;

}


if(kbhit())ch=getch();
switch(ch)
{case '1':{s1=!s1;
click(s1,s2,s3,s4);
outportb(port,1);delay(500);outport(port,0);
ch='0';break;
}
case '2':{s2=!s2;
click(s1,s2,s3,s4);
outportb(port,2);delay(500);outport(port,0);
ch='0';break;
}
case '3':{s3=!s3;
click(s1,s2,s3,s4);
outportb(port,4);delay(500);outport(port,0);
ch='0';break;
}
case '4':{s4=!s4;
click(s1,s2,s3,s4);
outportb(port,8);delay(500);outport(port,0);
ch='0';break;
}
case 32:{click(s1,s2,s3,s4);
reset(&s1,&s2,&s3,&s4);
ch='0';break;
}
case 27: {click(s1,s2,s3,s4);
reset(&s1,&s2,&s3,&s4);
closegraph();exit(0);}
}

}
}

void display(int s1,int s2,int s3,int s4)
{setbkcolor(9);setcolor(1);
rectangle(5,5,635,475);rectangle(10,10,630,470);
dispbutton(1);dispbutton(2);dispbutton(3);dispbutton(4);
dispbutton(5);dispbutton(6);
status(s1,s2,s3,s4);
setcolor(1);
outtextxy(100,115,"SWITCH 1");
outtextxy(220,115,"SWITCH 2");
outtextxy(340,115,"SWITCH 3");
outtextxy(460,115,"SWITCH 4");
outtextxy(115,315,"EXIT");
outtextxy(470,315,"RESET");
}

void dispbutton(int n)
{int x1,y1,x2,y2;
if(n==1){x1=80;y1=100;x2=180;y2=140;}
if(n==2){x1=200;y1=100;x2=300;y2=140;}
if(n==3){x1=320;y1=100;x2=420;y2=140;}
if(n==4){x1=440;y1=100;x2=540;y2=140;}
if(n==5){x1=80;y1=300;x2=180;y2=340;}
if(n==6){x1=440;y1=300;x2=540;y2=340;}
setfillstyle(SOLID_FILL,7);
bar(x1,y1,x2,y2);
setcolor(15);
line(x1,y1,x2,y1);line(x1,y1,x1,y2);
setcolor(8);
line(x2,y1,x2,y2);line(x1,y2,x2,y2);
}

void click(int s1,int s2,int s3,int s4)
{int x1,y1,x2,y2;
if(ch=='1'){x1=80;y1=100;x2=180;y2=140;}
if(ch=='2'){x1=200;y1=100;x2=300;y2=140;}
if(ch=='3'){x1=320;y1=100;x2=420;y2=140;}
if(ch=='4'){x1=440;y1=100;x2=540;y2=140;}
if(ch==27){x1=80;y1=300;x2=180;y2=340;}
if(ch==32){x1=440;y1=300;x2=540;y2=340;}
hidemouseptr();
setcolor(15);line(x2,y1,x2,y2);line(x1,y2,x2,y2);
setcolor(8);line(x1,y1,x2,y1);line(x1,y1,x1,y2);
sound(50);delay(75);nosound();
setcolor(15);line(x1,y1,x2,y1);line(x1,y1,x1,y2);
setcolor(8);line(x2,y1,x2,y2);line(x1,y2,x2,y2);
showmouseptr();
status(s1,s2,s3,s4);

}

void status(int s1,int s2,int s3,int s4)
{setcolor(4);setfillstyle(SOLID_FILL,4);
circle(130,200,10);
circle(250,200,10);
circle(370,200,10);
circle(490,200,10);
if(s1==1)floodfill(130,200,4);
else {setcolor(0);setfillstyle(SOLID_FILL,0);circle(130,200,10);
floodfill(130,200,0);
setcolor(4);circle(130,200,10);setfillstyle(SOLID_FILL,4);
}
if(s2==1)floodfill(250,200,4);
else {setcolor(0);setfillstyle(SOLID_FILL,0);circle(250,200,10);
floodfill(250,200,0);
setcolor(4);circle(250,200,10);setfillstyle(SOLID_FILL,4);
}
if(s3==1)floodfill(370,200,4);
else {setcolor(0);setfillstyle(SOLID_FILL,0);circle(370,200,10);
floodfill(370,200,0);
setcolor(4);circle(370,200,10);setfillstyle(SOLID_FILL,4);
}
if(s4==1)floodfill(490,200,4);
else {setcolor(0);setfillstyle(SOLID_FILL,0);circle(490,200,10);
floodfill(490,200,0);
setcolor(4);circle(490,200,10);
}
}

void reset(int *s1,int *s2,int *s3,int *s4)
{if(*s1==1)
{outportb(port,1);delay(500);outport(port,0);}
if(*s2==1)
{outportb(port,2);delay(500);outport(port,0);}
if(*s3==1)
{outportb(port,4);delay(500);outport(port,0);}
if(*s4==1)
{outportb(port,8);delay(500);outport(port,0);}
*s1=0;*s2=0;*s3=0;*s4=0;
status(*s1,*s2,*s3,*s4);
}