xref: /dragonfly/share/man/man4/dcons.4 (revision c880cbaf)
1.\" Copyright (c) 2003 Hidetoshi Shimokawa
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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 currently under development.
100