NetBSD/share/man/man4/man4.pc532/mem.4
agc 075022b349 Move UCB-licensed code from 4-clause to 3-clause licence.
Patches provided by Joel Baker in PR 22309, verified by myself.
2003-08-07 10:30:41 +00:00

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.\" Copyright (c) 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
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.\" modification, are permitted provided that the following conditions
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.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" from: @(#)mem.4 5.3 (Berkeley) 5/2/91
.\" $NetBSD: mem.4,v 1.4 2003/08/07 10:31:08 agc Exp $
.\"
.Dd December 23, 1995
.Dt MEM 4 pc532
.Os
.Sh NAME
.Nm mem ,
.Nm kmem
.Nd memory files
.Sh DESCRIPTION
The special file
.Nm /dev/mem
is an interface to the physical memory of the computer.
Byte offsets in this file are interpreted as physical memory addresses.
Reading and writing this file is equivalent to reading and writing
memory itself.
Only offsets within the bounds of
.Nm /dev/mem
are allowed.
.Pp
Kernel virtual memory is accessed through the interface
.Nm /dev/kmem
in the same manner as
.Nm /dev/mem .
Only kernel virtual addresses that are currently mapped to memory are allowed.
.Pp
On the
.Tn pc532 ,
physical memory is contiguous starting at address 0x00000000, EPROM starts
at 0x10000000, and devices start at 0x28000000.
.Sh FILES
.Bl -tag -width Pa -compact
.It Pa /dev/mem
.It Pa /dev/kmem
.El
.Sh HISTORY
The
.Nm mem ,
.Nm kmem
files appeared in
.At v6 .