/*
AUTHOR:Cagdas YILMAZ
FILE: DCmotor.C
DESC: Prompt user for decimal word. Returns associated analog voltage
*/
#include<stdio.h>
#include<stdlib.h>
#include<dos.h>
void main(void) {
int Volt, Choice, PORT;
int BASEADDR, PORTA, PORTB, PORTC, CNTRL;
gotoxy(1,1);
cprintf("Enter Base Address (decimal) e.g. 608\n");
gotoxy(1,2); scanf("%d", &BASEADDR);
PORTA = BASEADDR; PORTB = BASEADDR + 1; PORTC = BASEADDR + 2;
CNTRL = BASEADDR + 3;
outportb(CNTRL, 128); /* configure all ports for output */
do {
printf("Enter Port Choice\n");
printf("(1) Port A\n (2) Port B\n (3) Port C\n");
scanf("%d", &Choice);
if(Choice < 1 || Choice > 3)
{
printf("Enter 1, 2 or 3\n");
};
} while (Choice < 1 || Choice > 3);
switch (Choice) {
case 1 : PORT = PORTA; break;
case 2 : PORT = PORTB; break;
case 3 : PORT = PORTC; break;
};
printf("Enter 999 to quit\n");
printf("Input Decimal word (0 = -5V, 255 = +5V \n");
while(1) {
scanf("%d", &Volt);
if(Volt == 999) {
printf("Goodbye!\n");
outportb(PORT, 0); /* quitting */
exit(0);
};
outportb(PORT, Volt);
};
} /* end of main */