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Date: Tue, 19 Nov 1996 19:27:49 +0100 (MET)
Message-Id: <199611191827.TAA18620@chouette.inria.fr>
From: Emmanuel Duros <eduros@chouette.inria.fr>
To: freebsd-hackers@freebsd.org
Subject: Creating a device driv., Pb with outb, outw...
Reply-to: Emmanuel.Duros@sophia.inria.fr
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Hi,

I am going to write a device driver for a communication card which is
a receive-only interface for satellite links.

First, I would like to write a peace of code outside the kernel (in user
context) that would intialize the adapter with a sequence of outb
functions to the correct interface address.

With a very simple program such as:


#include<machine/cpufunc.h>

void main(void){
   
   outb( 0x300, 1 );
}

I always get a BUS ERROR. I also tried on the parallel port (0x378)
without success.

Any comments on this, why does this happen ?

I am using FreeBSD 2.2-961006-SNAP and I noticed there is no man on
these functions or on any low level functions, is this normal ?

Could you also reply to my personal Email ? Thanks...

Emmanuel