freebsd-skq/share/man/man4/ucom.4
allanjude 97ffdc179c Add cross references betwen ttys(5) and related drivers
nmdm(4), ucom(4), and uart(4)

PR:		247638
Submitted by:	Pau Amma <pauamma@gundo.com>
Reported by:	0mp
MFC after:	4 weeks
Sponsored by:	Klara Inc.
Event:		July 2020 Bugathon
2020-07-11 20:56:57 +00:00

169 lines
4.3 KiB
Groff

.\" $NetBSD: ucom.4,v 1.9 2002/03/22 00:39:40 augustss Exp $
.\"
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Lennart Augustsson.
.\"
.\" 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.
.\"
.\" 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.
.\"
.\" $FreeBSD$
.\"
.Dd July 11, 2020
.Dt UCOM 4
.Os
.Sh NAME
.Nm ucom
.Nd USB tty support
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following line in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device ucom"
.Ed
.Pp
Alternatively, to load the driver as a
module at boot time, place the following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
ucom_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver attaches to USB modems, serial ports, and other devices that need
to look like a tty.
The
.Nm
driver shows a behavior like a
.Xr tty 4 .
This means that normal programs such as
.Xr tip 1
or
.Xr ppp 8
can be used to access the device.
.Sh SYSCTL VARIABLES
The following variables are available as both
.Xr sysctl 8
variables and
.Xr loader 8
tunables:
.Bl -tag -width indent
.It Va hw.usb.ucom.debug
Debug output level, where 0 is debugging disabled and larger values increase
debug message verbosity.
Default is 0.
.It Va hw.usb.ucom.device_mode_console
When set to 1, the
.Nm
driver will mark terminals as console devices when operating in device mode.
Default is 1.
.It Va hw.usb.ucom.pps_mode
Enables and configure PPS capture mode as described below.
.El
.Sh Pulse Per Second (PPS) Timing Interface
The
.Nm
driver can capture PPS timing information as defined in RFC 2783.
The API, accessed via
.Xr ioctl 2 ,
is available on the tty device.
To use the PPS capture feature with
.Xr ntpd 8 ,
symlink the tty device to
.Va /dev/pps0.
.Pp
The
.Va hw.usb.ucom.pps_mode
sysctl configures the PPS capture mode.
It can be set in
.Xr loader.conf 5
or
.Xr sysctl.conf 5 .
The following capture modes are available:
.Bl -tag -compact -offset "mmmm" -width "mmmm"
.It 0
Capture disabled (default).
.It 1
Capture pulses on the CTS line.
.It 2
Capture pulses on the DCD line.
.El
.Sh FILES
.Bl -tag -width "/dev/ttyU*.init" -compact
.It Pa /dev/ttyU*
for callin ports
.It Pa /dev/ttyU*.init
.It Pa /dev/ttyU*.lock
corresponding callin initial-state and lock-state devices
.Pp
.It Pa /dev/cuaU*
for callout ports
.It Pa /dev/cuaU*.init
.It Pa /dev/cuaU*.lock
corresponding callout initial-state and lock-state devices
.El
.Sh SEE ALSO
.Xr cu 1 ,
.Xr tty 4 ,
.Xr uark 4 ,
.Xr ubsa 4 ,
.Xr ubser 4 ,
.Xr uchcom 4 ,
.Xr ucycom 4 ,
.Xr ufoma 4 ,
.Xr uftdi 4 ,
.Xr uhso 4 ,
.\".Xr ugensa 4 ,
.Xr uipaq 4 ,
.Xr umcs 4 ,
.Xr umct 4 ,
.Xr umodem 4 ,
.Xr umoscom 4 ,
.Xr uplcom 4 ,
.Xr usb 4 ,
.Xr uslcom 4 ,
.Xr uvisor 4 ,
.Xr uvscom 4 ,
.Xr ttys 5
.Sh HISTORY
The
.Nm
driver was adopted from
.Nx
in March of 2002.
This manual page was adopted from
.Nx
by
.An Tom Rhodes Aq Mt trhodes@FreeBSD.org
in April 2002.
.Sh BUGS
Prior to
.Fx 6.0
.Nm
created
.Pa /dev/ucom?
rather than the uniform device names created today.
Old scripts must be adjusted accordingly.