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To: Luiz de Barros <luiz@nlink.com.br>
cc: freebsd-hardware@FreeBSD.ORG
Subject: Re: talk to I/O Devices. 
In-reply-to: Your message of "Wed, 16 Apr 1997 10:18:14 -0300."
             <Pine.BSF.3.91.970416101425.14514I-100000@mirage.nlink.com.br> 
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Date: Wed, 16 Apr 1997 09:39:03 -0500
From: "Eric L. Hernes" <erich@lodgenet.com>
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Luiz de Barros writes:
>Dear FreeBSD Experts,
>
>I would like to know how i can talk to an input/output device attached to 
>some I/O ports in C. I want something equivalent to outportb and inportb 
>from DOS. The board we want to develop is a remote power controller to 
>reset our computers in case of a crash. The board will be controlled by 
>I/O ports.

#include <machine/cpufunc.h>
#include <fcntl.h>

int
main(int ac, char **av) {
  int fd;

  if((fd=open("/dev/io", O_RDWR))<0){
    perror("/dev/io");
    return 1;
  }
  outb(addr, val);
  inb(addr);
  outsw(addr, string);
  ...
  return 0;
}

should do it.

>
>Thanks in Advance,
>
>Luiz
>Nlink ISP.
>

eric.
-- 
erich@rrnet.com http://rrnet.com/~erich
erich@freebsd.org http://www.freebsd.org/~erich
erich@lodgenet.com