NetBSD/share/man/man4/zstty.4

92 lines
3.2 KiB
Groff

.\" $NetBSD: zstty.4,v 1.1 1997/10/28 17:14:53 gwr 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.
.\"
.Dd October 23, 1997
.Dt ZSTTY 4
.Os NetBSD 1.3
.Sh NAME
.Nm zstty
.Nd
serial communications interface
.Sh SYNOPSIS
.Cd "zstty* at zs0" Pq sparc
.Cd "zstty* at zsc1" Pq others
.Sh DESCRIPTION
The
.Nm
driver provides TTY support for Zilog 8530 Dual UARTS.
.Pp
Input and output for each line may set to any baud rate in the
range 50 to 38400 (and higher on some machines).
.Sh FILES
.Bl -tag -width Pa
.It Pa /dev/ttya
.It Pa /dev/ttyb
.El
.Sh DIAGNOSTICS
.Bl -tag -width indent -compact
.It zs0*: fifo overflow
.br
The on-chip
.Dq fifo
has overflowed and incoming data has been lost.
This generally means the machine is not responding to
interrupts from the ZS chip fast enough, which can be
remedied only by using a lower baud rate.
.It zs0*: ring overflow
.br
The software input
.Dq ring
has overflowed. This usually means input flow-control
is not configured correctly (i.e. incorrect cable wiring).
.El
.Sh SEE ALSO
.Xr scc 4
.Xr tty 4
.Sh HISTORY
The
.Nm
driver was derived from the
.Nm sparc
.Nm zs
driver supplied with 4.4 BSD.
.Ud
.Sh BUGS
The old Zilog 8530 chip has a very small fifo (3 bytes?) and
therefore has very strict latency requirements for the
interrupt service routine. This limits the usable baud rates
on many machines.