.\"	$OpenBSD: dart.4,v 1.3 2013/10/15 18:15:04 miod Exp $
.\"
.\" Copyright (c) 2013 Miodrag Vallat.
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
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.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate: October 15 2013 $
.Dt DART 4 mvme88k
.Os
.Sh NAME
.Nm dart
.Nd MC68681 or MC68692 dual UART
.Sh SYNOPSIS
.Cd "dart0 at angelfire0 offset 0x640000 ipl 5"
.Cd "dart0 at syscon0 offset 0x82000 ipl 3"
.Sh DESCRIPTION
The MC68681 and MC68692 dual asynchronous receiver/transmitter
.Pq Tn DUART
component provides two serial ports, as well as a 16-bit programmable
counter/timer.
.Pp
The
.Nm
driver provides support for the two serial ports found onboard
MVME180, MVME181 and MVME188 systems.
.Pp
The
.Nm
serial ports have a two character buffer on the transmit path, and a four
character buffer on the receive path.
.Pp
The following link speeds are supported by the
.Nm
driver:
50, 75, 110, 134.5, 150, 200, 300, 600, 1050, 1200, 1800, 200, 2400, 4800,
7200, 9600, 19200 and 38400 bps.
.Pp
On MVME180 and MVME181, the counter/timer is used to provide the
scheduling clock, while on MVME188, the counter/timer is used to provide
the statistics clock.
.Sh FILES
.Bl -tag -width Pa -compact
.It Pa /dev/ttya
.It Pa /dev/ttyb
.El
.Sh SEE ALSO
.Xr intro 4 ,
.Xr tty 4