.\" Copyright (c) 2018-2020 Robin Getz
.\" Copyright (c) 2018-2020 Analog Devices Inc.
.\"
.\" %%%LICENSE_START(GPLv2+_DOC_FULL)
.\" This is free documentation; you can redistribute it and/or
.\" modify it under the terms of the GNU General Public License as
.\" published by the Free Software Foundation; either version 2 of
.\" the License, or (at your option) any later version.
.\"
.\" The GNU General Public License's references to "object code"
.\" and "executables" are to be interpreted as the output of any
.\" document formatting or typesetting system, including
.\" intermediate and printed output.
.\"
.\" This manual is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public
.\" License along with this manual; if not, see
.\" <http://www.gnu.org/licenses/>.
.\" %%%LICENSE_END
.\"
.TH iio_writedev 1 "19 November 2020" "libiio-0.21" "LibIIO Utilities"
.IX iio_writedev_
.SH NAME
iio_writedev \- write buffers on an IIO device
.SH SYNOPSIS
.B iio_writedev
[
.I options
]
[-n <hostname>] [-t <trigger>] [-T <timeout-ms>] [-b <buffer-size>] [-s <samples>] <iio_device> [<channel> ...]
.SH DESCRIPTION
.B iio_reg
is a utility for writing buffers from connected IIO devices.

.SH OPTIONS
.TP
.B \-h, \-\-help
Tells
.I iio_readdev
to display some help, and then quit.
.B \-n, \-\-network
Use the network backend with the provided hostname
.TP
.B \-u, \-\-uri
The Uniform Resource Identifier
.I (uri)
for connecting to devices, can be one of:
.RS
.IP ip:[address]
network address, either numeric (192.168.0.1) or network hostname
.IP ip:
blank, if compiled with zeroconf support, will find an IIO device on network
.IP usb:[device:port:instance]
normally returned from
.B iio_info -s
.IP serial:[port]
.IP local
with no address part
.RE
.TP
.B \-t \-\-trigger
Use the specified trigger, if needed on the specified channel
.TP
.B \-b \-\-buffer-size
Size of the capture buffer. Default is 256.
.TP
.B \-s \-\-samples
Number of samples (not bytes) to capture, 0 = infinite. Default is 0.
.TP
.B \-T \-\-timeout
Buffer timeout in milliseconds. 0 = no timeout. Default is 0.
.TP
.B \-a, \-\-auto
Scan for available contexts and if only one is available use it.
.TP
.B \-c \-\-cyclic
Use cyclic buffer mode.

.SH RETURN VALUE
If the specified device is not found, a non-zero exit code is returned.

.SH "USAGE"
.PP 
You use iio_readdev in the same way you use many of the other libiio utilities.
You must specify a IIO device, and the specific channel to read. Since this is a write, channels must be output.
It is easy to use
.B iio_attr
to find out what the channels are called.
.PP
This identifies the device, and channel that can be used.
.RS
.B \f(CWiio_attr \-a \-o \-c .\fP
.br
\f(CWUsing auto-detected IIO context at URI "usb:3.10.5"\fP
.br
dev 'cf-ad9361-dds-core-lpc', channel 'voltage0' (output, index: 0, format: le:S16/16>>0)
.br
dev 'cf-ad9361-dds-core-lpc', channel 'voltage1' (output, index: 1, format: le:S16/16>>0)
.RE
.PP
This sends 1024 samples of I and Q data to the USB attached AD9361. data is taking from standard in, in a binary format.
.RS
.B \f(CWiio_writedev \-a \-s 1024 cf-ad9361-dds-core-lpc voltage0 voltage1 < ./samples.dat\fP
.RE

.SH "SEE ALSO"
.ad l
.BR iio_attr (1),
.BR iio_info (1),
.BR iio_readdev (1),
.BR iio_reg (1),
.BR iio_writedev (1),
.BR libiio (3)
.PP
libiio home page:
.BR \%https://wiki.analog.com/resources/tools-software/linux-software/libiio
.PP
libiio code:
.BR \%https://github.com/analogdevicesinc/libiio
.PP
Doxygen for libiio
.BR \%https://analogdevicesinc.github.io/libiio/
.SH BUGS
All bugs are tracked at:
.BR \%https://github.com/analogdevicesinc/libiio/issues