xref: /netbsd-src/share/man/man4/man4.vax/dmz.4 (revision ce0bb6e8d2e560ecacbe865a848624f94498063b)
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32.\"     from: @(#)dmz.4	6.4 (Berkeley) 3/27/91
33.\"	$Id: dmz.4,v 1.2 1993/08/01 07:36:26 mycroft Exp $
34.\"
35.Dd March 27, 1991
36.Dt DMZ 4 vax
37.Os BSD 4.2
38.Sh NAME
39.Nm dmz
40.Nd
41.Tn DMZ-32
42terminal multiplexor
43.Sh SYNOPSIS
44.Cd "device dmz0 at uba? csr 0160540" "vector dmzrinta dmzxinta dmzrintb dmzxintb dmzrintc dmzxintc"
45.Sh DESCRIPTION
46The
47.Nm dmz
48device provides 24 lines of asynchronous serial line support.
49Modem control on all ports is available
50as an option for the H3014 distribution panel.
51.Pp
52An optional argument
53.Ar flags
54may be supplied with the device specification for
55.Nm dmz
56in the config file indicating
57that the line corresponding to
58bit number
59.Ar i
60is not properly
61connected, and should be treated as hard-wired with carrier
62always present.  Thus specifying
63.Ql flags 0x000004
64for
65.Li dmz0
66would cause line
67.Pa ttya2
68to be treated in this way.
69.Pp
70Normal
71.Tn I/O
72control parameters for individual lines are managed by
73.Xr ioctl 2
74calls.
75Line speeds (there are 16 choices for the
76.Tn DMZ )
77may be initiated via
78.Xr getty 8
79and
80.Xr stty 1
81or may be communicated by other programs which
82utilize
83.Xr ioctl
84such as
85.Xr ifcongif 8 ,
86see
87.Xr tty 4  .
88.Pp
89The
90.Nm dmz
91driver normally enables the input silos with a short timeout
92(30 milliseconds); this allows multiple characters to be received
93per interrupt during periods of high-speed input.
94.Sh FILES
95.Bl -tag -width /dev/tty[abcefg][0-9a-n] -compact
96.It Pa /dev/tty[abcefg][0-9a-n]
97.El
98.Sh DIAGNOSTICS
99.Bl -diag
100.It dmz%d: NXM line %d.
101No response from the
102.Tn UNIBUS
103on a
104.Tn DMA
105transfer
106within a timeout period.  This is often followed by a
107.Tn UNIBUS
108adapter
109error.  This occurs most frequently when the
110.Tn UNIBUS
111is heavily loaded
112and when devices which hog the bus (such as
113.Tn RK07 Ns s )
114are present.
115It is not serious.
116.Pp
117.It dmz%d: silo overflow.
118The character input silo overflowed
119before it could be serviced.  This can happen if a hard error occurs
120when the
121.Tn CPU
122is running with elevated priority, as the system will
123then print a message on the console with interrupts disabled.
124It is not serious.
125.El
126.Sh SEE ALSO
127.Xr tty 4
128.Sh HISTORY
129The
130.Nm
131driver appeared in
132.Bx 4.3 .
133.Sh BUGS
134It should be possible to set the silo timeout with a configuration file option,
135as the value is a trade-off between efficiency and response time for flow
136control and character echo.
137