/*program to control devices using PC parallel port
The devices are controlled by pressing the keys 1-8
that corresponds to each of the 8 possible devices
*/

#include<dos.h>
#include<stdio.h>
#include<conio.h>
#define PORT 0x378 /* This is the parallel port address */

main()
{
char val=0,key=0;
char str1[]="ON ";
char str2[]="OFF";
char *str;
clrscr();
printf("Press the approriate number key to turn on/off devices:\n\n");
printf("Here Device1 is connected to D0 of parallel port and so on\n\n");
printf("Press \"x\" to quit\n\n");
gotoxy(1,8);
printf("Device1:OFF Device2:OFF Device3:OFF Device4:OFF\n");
printf("Device5:OFF Device6:OFF Device7:OFF Device8:OFF");

while(key!='x' && key!='X')
{
gotoxy(1,12);
printf("Value in hex sent to the port:");
key=getch();
switch(key){

case '1':

	gotoxy(9,8);
	val=(val&0x01)?(val&(~0x01)):val|0x01;
	str=(val&0x01)?str1:str2;
	printf("%s",str);
	outportb(PORT,val);
	gotoxy(1,13);
	printf("%x",val);
	break;

case '2':

	gotoxy(21,8);
	val=(val&0x02)?(val&(~0x02)):val|0x02;
	str=(val&0x02)?str1:str2;
	printf("%s",str);
	outportb(PORT,val);
	gotoxy(1,13);
	printf("%x",val);
	break;

case '3':

	gotoxy(33,8);
	val=(val&0x04)?(val&(~0x04)):val|0x04;
	str=(val&0x04)?str1:str2;
	printf("%s",str);
	outportb(PORT,val);
	gotoxy(1,13);
	printf("%x",val);
	break;

case '4':

	gotoxy(45,8);
	val=(val&0x08)?(val&(~0x08)):val|0x08;
	str=(val&0x08)?str1:str2;
	printf("%s",str);
	outportb(PORT,val);
	gotoxy(1,13);
	printf("%x",val);
	break;

case '5':

	gotoxy(9,9);
	val=(val&0x10)?(val&(~0x10)):val|0x10;
	str=(val&0x10)?str1:str2;
	printf("%s",str);
	outportb(PORT,val);
	gotoxy(1,13);
	printf("%x",val);
	break;

case '6':

	gotoxy(21,9);
	val=(val&0x20)?(val&(~0x20)):val|0x20;
	str=(val&0x20)?str1:str2;
	printf("%s",str);
	outportb(PORT,val);
	gotoxy(1,13);
	printf("%x",val);
	break;

case '7':

	gotoxy(33,9);
	val=(val&0x40)?(val&(~0x40)):val|0x40;
	str=(val&0x40)?str1:str2;
	printf("%s",str);
	outportb(PORT,val);
	gotoxy(1,13);
	printf("%x",val);
	break;

case '8':
	gotoxy(45,9);
	val=(val&0x80)?(val&(~0x80)):val|0x80;
	str=(val&0x80)?str1:str2;
	printf("%s",str);
	outportb(PORT,val);
	gotoxy(1,13);
	printf("%x",(unsigned char)val);
	break;

	}

}


}