.\"	$OpenBSD: zsc.4,v 1.3 2004/09/30 19:59:27 mickey Exp $
.\"	$NetBSD: zstty.4,v 1.7 2003/05/06 08:15:04 wiz Exp $
.\"
.\" Copyright (c) 1997 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Gordon W. Ross.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"        This product includes software developed by the NetBSD
.\"        Foundation, Inc. and its contributors.
.\" 4. Neither the name of The NetBSD Foundation nor the names of its
.\"    contributors may be used to endorse or promote products derived
.\"    from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.\" Copyright (c) 1990, 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the Systems Programming Group of the University of Utah Computer
.\" Science Department.
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     from: @(#)dca.4	5.2 (Berkeley) 3/27/91
.\"	$NetBSD: zsc.4,v 1.5 2003/08/07 10:31:07 agc Exp $
.\"
.Dd March 8, 2004
.Dt ZSC 4 mac68k
.Os
.Sh NAME
.Nm zsc
.Nd
.Tn Zilog
8530 (ZSCC) serial communications driver
.Sh SYNOPSIS
.Cd "zsc0 at obio?"
.Cd "zstty* at zsc?"
.Sh DESCRIPTION
The
.Nm
driver provides support for Z8530- and Z85230-compatible
.Tn EIA
.Tn RS-232C
.Pf ( Tn CCITT
.Tn V.28 )
Dual
.Tn UART
chips.
The Z8530 has a 3 character buffer, while the Z85230 has a 8 character buffer.
However, due to limitations in the design of the Z85230, the driver is unable
to distinguish it from the Z8530 and will not enable any enhanced features of
the device.
.Pp
Input and output for each line may be set to any baud rate in the
range from 50 to 115200 (though some machines will not support more than
38400 reliably).
.Pp
The
.Nm zstty
driver provides a terminal interface, supporting all the standard
.Xr tty 4
ioctl calls.
.Sh FILES
.Bl -tag -width /dev/ttya -compact
.It Pa /dev/ttya
.It Pa /dev/ttyb
.El
.Sh SEE ALSO
.Xr ioctl 2 ,
.Xr intro 4 ,
.Xr obio 4 ,
.Xr tty 4
.Sh BUGS
Due to the small character buffer on the
.Tn Zilog
8530 chip, the driver has very strict latency requirements for its interrupt
service routine.
As a result, data loss may occur when using high speeds, particularly on older
(68020 or 68030) Macintosh models and on busy systems.