.\" Copyright (c) 1980 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"	@(#)dtab.5	2.3 (Berkeley) 1/22/87
.\"
.TH DTAB 5 "January 22, 1987"
.UC 2
.SH NAME
dtab \- automatic system configuration device table (2BSD)
.SH DESCRIPTION
The
.I dtab
file contains a list of the devices that the
.IR autoconfig (8)
program will attempt to attach to the system.
.PP
Each line describes one device which may be present on the system;
additional devices of the same type require additional lines.
The line contains at least six fields separated by white space.
Blank lines and comments can appear anywhere in the file except
between fields; comments
are delimited by `#' and new line.  The fields are (in order):
.TP "\w'handler(s)  'u"
dev
The device name, usually two characters
.TP
unit
Either a unit number or a `?' indicating automatic selection of unit numbers.
.TP
addr
The address of the device's first register, as a 16-bit octal number.
.TP
vector
The interrupt vector, in octal.
.TP
BR
The priority at which the device interrupts.
.TP
handler(s)
One or more routine names with which the interrupt vector is filled.
.SH EXAMPLE
.nf
.sp
.dt
.ta .5i +\w'dm  ?  'u +\w'160020  'u +\w'Vector  'u +\w'5  'u +\w'dhrint dhxint   'u
#               Device Configuration Table
#    Clock and console are pre-configured and should not be listed here
#
# Dev#	Addr	Vector	Br	Handler(s)	# Comment
lp	?	177514	200	4	lpio	# lp-11 line printer
ht	0	172440	224	5	htintr	# tu 16 massbus tape
xp	?	176700	254	5	xpio	# xp driver
dm	?	170500	310	4	dmin	# dm11 dh modem control
dh	?	160020	320	5	dhin dhou	# dh11 terminal mux
dz	?	160110	330	5	dzin dzdma	# dz11 terminal mux
.fi
.SH FILES
.ta 2i
/etc/dtab	device table
.SH SEE ALSO
autoconfig(8)
.SH BUGS
.I /Etc/dtab
is unique to the PDP-11 and 2BSD.