.\"	$OpenBSD: zs.4,v 1.6 1999/07/09 13:35:42 aaron Exp $
.\"
.\" Copyright (c) 1998 The OpenBSD Project
.\" All rights reserved.
.\"
.\"
.Dd March 4, 1998
.Dt ZS 4 sparc
.Os
.Sh NAME
.Nm zs
.Nd Zilog 8530 (ZSCC) serial communications driver
.Sh SYNOPSIS
.Cd "zs0 at mainbus0                                  " Pq sun4c
.Cd "zs0 at obio0                                     " Pq sun4m
.Cd "zs0 at obio0 addr 0xf1000000 level 12 flags 0x103" Pq sun4/[23]00
.Cd "zs0 at obio0 addr 0x01000000 level 12 flags 0x103" Pq sun4/100
.Cd "zs1 at mainbus0                                  " Pq sun4c
.Cd "zs1 at obio0                                     " Pq sun4m
.Cd "zs1 at obio0 addr 0xf0000000 level 12 flags 0x103" Pq sun4/[23]00
.Cd "zs1 at obio0 addr 0x00000000 level 12 flags 0x103" Pq sun4/100
.Cd "zs2 at obio0 addr 0xe0000000 level 12 flags 0x103" Pq sun4/300
.Sh DESCRIPTION
The
.Nm
is a Zilog 8530 serial interface chip used in Sun workstations.
The Zilog 8530 provides two input/output channels per instance.
Most Sun workstations include two of these interfaces.  One of the
interfaces is hardwired for use by the keyboard and mouse attached to
the workstation console.
The remaining additional
.Nm
interfaces provide RS-423
and RS-232 serial ports for general purpose use.
.Pp
The
.Nm
driver supports all of the standard
.Xr tty 4
ioctl calls.
The status of the DTR, RTS, CTS, and DCD signals can be queried with
TIOCMGET command, but, due to limitations in the hardware,
only the DTR and RTS signals can be modified with TIOCMSET, TIOCMBIC,
and TIOCMBIS
.Xr ioctl 2
commands.
.Sh BUGS
The
.Nm
driver now supports cua minor devices, but with this known deficiency
in the simultaneous outgoing/incoming aspect of the driver:
The first outgoing connection succeeds, but second and subsequent
connections fail, apparently due to a getty hang. The hung getty apparently
prevents the cua device from being re-opened.
.Sh SEE ALSO
.Xr ioctl 2 ,
.Xr kbd 4 ,
.Xr ms 4 ,
.Xr tty 4
.Sh HISTORY
The
.Nm
driver first appeared in
.Bx 4.4 .
Support for the TIOCM* ioctl's appeared in
.Ox 2.3 .