xref: /netbsd-src/share/man/man4/man4.vax/dmf.4 (revision 721f013c3dccf382f4ff007505a6e4eeae891802)
1.\"	$NetBSD: dmf.4,v 1.15 2017/08/01 11:11:17 wiz Exp $
2.\"
3.\" Copyright (c) 1983, 1991, 1993
4.\"	The Regents of the University of California.  All rights reserved.
5.\"
6.\" Redistribution and use in source and binary forms, with or without
7.\" modification, are permitted provided that the following conditions
8.\" are met:
9.\" 1. Redistributions of source code must retain the above copyright
10.\"    notice, this list of conditions and the following disclaimer.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice, this list of conditions and the following disclaimer in the
13.\"    documentation and/or other materials provided with the distribution.
14.\" 3. Neither the name of the University nor the names of its contributors
15.\"    may be used to endorse or promote products derived from this software
16.\"    without specific prior written permission.
17.\"
18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28.\" SUCH DAMAGE.
29.\"
30.\"     from: @(#)dmf.4	8.1 (Berkeley) 6/5/93
31.\"
32.Dd February 17, 2017
33.Dt DMF 4 vax
34.Os
35.Sh NAME
36.Nm dmf
37.Nd
38.Tn DMF-32
39serial terminal multiplexor
40.Sh SYNOPSIS
41.Cd "dmf0 at uba? csr 0160340 vector dmfsrint dmfsxint dmfdaint dmfdbint dmfrint dmfxint dmflint"
42.Sh DESCRIPTION
43NOTE: This driver has not been ported from
44.Bx 4.4
45yet.
46.Pp
47The
48.Nm dmf
49device provides 8 lines of asynchronous serial line support.
50The first two of these have full modem control.
51The device also provides a line printer port
52similar to the
53.Tn LP-11 .
54Other features of the
55.Tn DMF-32
56are not supported.
57During autoconfiguration, the driver examines the configuration of each
58.Tn DMF-32
59and adjusts the interrupt vectors so that fewer vector locations are used
60if possible.
61.Pp
62An optional argument
63.Ar flags
64may be supplied with the device specification
65in the config file indicating
66that the line corresponding to
67bit number
68.Ar i
69is not properly
70connected, and should be treated as hard-wired with carrier
71always present.
72Thus specifying
73.Ql flags 0x04
74for
75.Li dmf0
76would cause line
77.Pa ttyA2
78to be treated in this way.
79Flags should be set for all lines without hardware support for modem control.
80.Pp
81Normal
82.Tn I/O
83control parameters for individual lines are managed by
84.Xr ioctl 2
85calls.
86Line speeds may be initiated via
87.Xr getty 8
88and
89.Xr stty 1
90or may be communicated by other programs which
91use
92.Xr ioctl 2
93such as
94.Xr ifconfig 8 ,
95see
96.Xr tty 4 .
97.Pp
98The serial line part of the
99.Nm dmf
100driver normally enables the input silos with a short timeout
101(30 milliseconds); this allows multiple characters to be received
102per interrupt during periods of high-speed input.
103.Pp
104A line printer port on a
105.Nm dmf
106is designated by
107a minor device number of the form
108.Pf 128+ Ns Ar n .
109See
110.Xr MAKEDEV 8 .
111Column and lines per page may be changed from the default
112132 columns and 66 lines by encoding the number of columns
113in bits 8-15 of flags and the number of lines in bits 16-23.
114This device does not provide the fancy output canonicalization
115features of the
116.Xr vax/lp 4
117driver.
118.Sh FILES
119.Bl -tag -width "/dev/tty[A-CE-I][0-7]" -compact
120.It Pa /dev/tty[A-CE-I][0-7]
121.It Pa /dev/ttyd[0-7]
122.It Pa /dev/lp
123.El
124.Sh DIAGNOSTICS
125.Bl -diag
126.It dmf%d: NXM line %d.
127No response from
128.Tn UNIBUS
129on a DMA transfer
130within a timeout period.
131This is often followed by a
132.Tn UNIBUS
133adapter
134error.
135This occurs most frequently when the
136.Tn UNIBUS
137is heavily loaded
138and when devices which hog the bus (such as
139.Tn RK07 Ns s )
140are present.
141It is not serious.
142.It dmf%d: silo overflow.
143The character input silo overflowed
144before it could be serviced.
145This can happen if a hard error occurs when the
146.Tn CPU
147is running with elevated priority, as the system will
148then print a message on the console with interrupts disabled.
149It is not serious.
150.It dmfsrint, dmfsxint, dmfdaint, dmfdbint.
151One of the unsupported parts of the dmf interrupted; something
152is amiss, check your interrupt vectors for a conflict with another
153device.
154.El
155.Sh SEE ALSO
156.Xr tty 4
157.Sh HISTORY
158The
159.Nm
160driver appeared in
161.Bx 4.2 .
162.Sh BUGS
163It should be possible to set the silo timeout with a configuration file option,
164as the value is a trade-off between efficiency and response time for flow
165control and character echo.
166