/* Prog for PWM on the parallel port */

/****************************************
*Because the ouput pulse was originaly	*
*5.5 times what it should be, I divided	*
*the on time and off time by 5. This 	*
*means the final pulse period is	*
*slightly above the specified 0.8s	*
*(+4x10-2)				*
****************************************/

#include <stdio.h>
#include <conio.h>
#include <dos.h>		/*For struct time*/
int LPT = 0x378;		/* Assign a var name to parallel port*/


void main(void)
{
	int i = 0;
	struct time curTime;	/*Create a variable called curTime of type struct time*/
	struct time newTime;	/*Create a variable called newTime of type struct time*/
                
	while(1){
		gettime (&curTime);
		i = 0;
		outp(LPT, 0xFF);/*Turn the pins HIGH*/
		while (i < 9){	/*48 hundredths divided by 5.5, because inital pulse was out by a factor of 5.5*/
			
			gettime(&newTime);

			if(curTime.ti_hund != newTime.ti_hund){
				curTime.ti_hund = newTime.ti_hund;
				i++;
			}
                }
		i = 0;
		outp(LPT, 0x00);/*Turn the pins LOW*/
		while (i < 6){  /*32 hundredths divided by 5.5, because inital pulse was out by a factor of 5.5*/
			
			gettime(&newTime);

			if(curTime.ti_hund != newTime.ti_hund){
				curTime.ti_hund = newTime.ti_hund;
				i++;
			}	
		}
        }
}