xref: /dragonfly/share/man/man4/dcons.4 (revision 5153f92b)
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.\" $DragonFly: src/share/man/man4/dcons.4,v 1.1 2004/09/23 06:44:30 simokawa Exp $
27.\"
28.Dd February 11, 2003
29.Dt DCONS 4
30.Os
31.Sh NAME
32.Nm dcons
33.Nd dumb console device driver
34.Sh SYNOPSIS
35.Cd device dcons
36.Pp
37.Cd options DDB
38.Cd options ALT_BREAK_TO_DEBUGGER
39.Pp
40.Cd device firewire
41.Sh DESCRIPTION
42The
43.Nm
44device is a simple console device which just reads from and writes to
45an allocated buffer for input and output respectively.
46It is of no use by itself and it is supposed that the buffer is accessed
47via a bus like
48.Xr firewire 4
49or
50.Xr kvm 3
51for interaction.
52.Pp
53The buffer consists of 4 channels.
54There are 2 ports, one for the console TTY and another is GDB port,
55then each port has an input channel and an output channel.
56.Sh EXAMPLES
57If you want to run
58.Xr getty 8
59on
60.Nm ,
61insert the following line into
62.Xr /etc/ttys 5
63and send a
64.Dv HUP
65signal to
66.Xr init 8
67using
68.Xr kill 1 .
69.Bd -literal -offset indent
70dcons	"/usr/libexec/getty std.9600"	vt100	on  secure
71.Ed
72.Pp
73Once the
74.Xr fwochi 4
75device is initialized to allow physical access,
76the buffer can be accessed from another host via a
77.Xr firewire 4
78bus using the
79.Xr dconschat 8
80application.
81See
82.Xr dconschat 8
83for more details.
84.Sh FILES
85.Bl -tag -width indent -compact
86.It Pa /dev/dcons
87.It Pa /etc/ttys
88.El
89.Sh SEE ALSO
90.Xr dcons_crom 4 ,
91.Xr ddb 4 ,
92.Xr firewire 4 ,
93.Xr fwohci 4 ,
94.Xr ttys 5 ,
95.Xr dconschat 8 ,
96.Xr fwcontrol 8
97.Sh AUTHORS
98.An Hidetoshi Shimokawa Aq simokawa@FreeBSD.org
99.Sh BUGS
100This driver is
101.Ud .
102