xref: /freebsd/share/man/man4/dcons.4 (revision 6b3455a7665208c366849f0b2b3bc916fb97516e)
1.\" Copyright (c) 2003 Hidetoshi Shimokawa
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25.\" $FreeBSD$
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 EXAMPLES
56If you want to run
57.Xr getty 8
58on
59.Nm ,
60insert the following line into
61.Xr /etc/ttys 5
62and send a
63.Dv HUP
64signal to
65.Xr init 8
66using
67.Xr kill 1 .
68.Bd -literal -offset indent
69dcons	"/usr/libexec/getty std.9600"	vt100	on  secure
70.Ed
71.Pp
72Once the
73.Xr fwochi 4
74device is initialized to allow physical access,
75the buffer can be accessed from another host via a
76.Xr firewire 4
77bus using the
78.Xr dconschat 8
79application.
80See
81.Xr dconschat 8
82for more details.
83.Sh FILES
84.Bl -tag -width indent -compact
85.It Pa /dev/dcons
86.It Pa /etc/ttys
87.El
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 simokawa@FreeBSD.org
98.Sh BUGS
99This driver is
100.Ud .
101