1.\" Copyright (c) 2003 Hidetoshi Shimokawa 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 14.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 15.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 16.\" DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 17.\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 18.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 19.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 21.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 22.\" ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 23.\" POSSIBILITY OF SUCH DAMAGE. 24.\" 25.\" $FreeBSD: src/share/man/man4/dcons.4,v 1.5 2004/06/17 19:51:17 ru Exp $ 26.\" 27.Dd February 11, 2003 28.Dt DCONS 4 29.Os 30.Sh NAME 31.Nm dcons 32.Nd dumb console device driver 33.Sh SYNOPSIS 34.Cd device dcons 35.Pp 36.Cd options DDB 37.Cd options ALT_BREAK_TO_DEBUGGER 38.Pp 39.Cd device firewire 40.Sh DESCRIPTION 41The 42.Nm 43device is a simple console device which just reads from and writes to 44an allocated buffer for input and output respectively. 45It is of no use by itself and it is supposed that the buffer is accessed 46via a bus like 47.Xr firewire 4 48or 49.Xr kvm 3 50for interaction. 51.Pp 52The buffer consists of 4 channels. 53There are 2 ports, one for the console TTY and another is GDB port, 54then each port has an input channel and an output channel. 55.Sh FILES 56.Bl -tag -width indent -compact 57.It Pa /dev/dcons 58.It Pa /etc/ttys 59.El 60.Sh EXAMPLES 61If you want to run 62.Xr getty 8 63on 64.Nm , 65insert the following line into 66.Pa /etc/ttys 67and send a 68.Dv HUP 69signal to 70.Xr init 8 71using 72.Xr kill 1 . 73.Bd -literal -offset indent 74dcons "/usr/libexec/getty std.9600" vt100 on secure 75.Ed 76.Pp 77Once the 78.Xr fwohci 4 79device is initialized to allow physical access, 80the buffer can be accessed from another host via a 81.Xr firewire 4 82bus using the 83.Xr dconschat 8 84application. 85See 86.Xr dconschat 8 87for more details. 88.Sh SEE ALSO 89.Xr dcons_crom 4 , 90.Xr ddb 4 , 91.Xr firewire 4 , 92.Xr fwohci 4 , 93.Xr ttys 5 , 94.Xr dconschat 8 , 95.Xr fwcontrol 8 96.Sh AUTHORS 97.An Hidetoshi Shimokawa Aq Mt simokawa@FreeBSD.org 98.Sh BUGS 99This driver is 100.Ud 101