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From: riku@field.fi (Riku Kalinen / Systems)
Newsgroups: comp.sys.m68k
Subject: Re: How to access local I/O devices from a user process in SysV/68?
Message-ID: <1990Dec4.060937.6685@field.fi>
Date: 4 Dec 90 06:09:37 GMT
References: <1990Dec3.040634.1428@cs.UAlberta.CA>
Organization: Field Oy, Helsinki, Finland, Europe
Lines: 21

In article <1990Dec3.040634.1428@cs.UAlberta.CA> rasit@cs.UAlberta.CA
(M. Rasit Eskicioglu) writes:

>I want to write code that would access to Local I/O Devices directly. For
>example, I want to read LANCE registers. As they are not mapped into the
>user's space in SysV/68V3R6, I always get memory protection error (signal 11). 
As You should. It is not safe to access I/O hw from user task.

>Is there a way to accomplish this task. It is possible, in SunOS for example,
>to map those locations into the user space via system calls. 

This sounds, in general, bad idea to my ears. I am not sure, if it is
possible at all, but shmxxx calls might get something out for you.



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Riku "the bit" Kalinen                    E-Mail : riku@gandalf.Field.FI
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