.\" Copyright (c) 2003 Hidetoshi Shimokawa
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 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.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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.\" DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
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.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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.\" $FreeBSD: src/share/man/man4/dcons.4,v 1.5 2004/06/17 19:51:17 ru Exp $
.\" $DragonFly: src/share/man/man4/dcons.4,v 1.3 2006/04/17 18:01:37 swildner Exp $
.\"
.Dd February 11, 2003
.Dt DCONS 4
.Os
.Sh NAME
.Nm dcons
.Nd dumb console device driver
.Sh SYNOPSIS
.Cd device dcons
.Pp
.Cd options DDB
.Cd options ALT_BREAK_TO_DEBUGGER
.Pp
.Cd device firewire
.Sh DESCRIPTION
The
.Nm
device is a simple console device which just reads from and writes to
an allocated buffer for input and output respectively.
It is of no use by itself and it is supposed that the buffer is accessed
via a bus like
.Xr firewire 4
or
.Xr kvm 3
for interaction.
.Pp
The buffer consists of 4 channels.
There are 2 ports, one for the console TTY and another is GDB port,
then each port has an input channel and an output channel.
.Sh FILES
.Bl -tag -width indent -compact
.It Pa /dev/dcons
.It Pa /etc/ttys
.El
.Sh EXAMPLES
If you want to run
.Xr getty 8
on
.Nm ,
insert the following line into
.Pa /etc/ttys
and send a
.Dv HUP
signal to
.Xr init 8
using
.Xr kill 1 .
.Bd -literal -offset indent
dcons	"/usr/libexec/getty std.9600"	vt100	on  secure
.Ed
.Pp
Once the
.Xr fwohci 4
device is initialized to allow physical access,
the buffer can be accessed from another host via a
.Xr firewire 4
bus using the
.Xr dconschat 8
application.
See
.Xr dconschat 8
for more details.
.Sh SEE ALSO
.Xr dcons_crom 4 ,
.Xr ddb 4 ,
.Xr firewire 4 ,
.Xr fwohci 4 ,
.Xr ttys 5 ,
.Xr dconschat 8 ,
.Xr fwcontrol 8
.Sh AUTHORS
.An Hidetoshi Shimokawa Aq simokawa@FreeBSD.org
.Sh BUGS
This driver is
.Ud .