xref: /freebsd/share/man/man4/dcons.4 (revision b7da444256a917b66463ccbee83f957d773badca)

.\" Copyright (c) 2003 Hidetoshi Shimokawa
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.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 respectivly.
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 other is GDB ports then each port
has an input channel and an output channel.
.Sh EXAMPLE
If you want to run
.Xr getty 8
on dcons, insert the following line into
.Xr /etc/ttys 5
and
send a 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 fwochi 4
device is initialized to allow physical access,
the buffer can be accessed from another host via a FireWire bus using the
.Xr dconschat 8
application. See
.Xr dconschat 8
for more details.
.Pp
.Sh FILES
.Bl -tag -width indent -compact
.It Pa /dev/dcons
.It Pa /etc/ttys
.El
.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 still under development.
.Pp