.\" Copyright (c) 2018-2020 Robin Getz
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.TH iio_readdev 1 "24 January 2023" "libiio-0.24" "LibIIO Utilities"
.IX iio_readdev_
.SH NAME
iio_readdev \- read buffers from an IIO device
.SH SYNOPSIS
.B iio_readdev
[
.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 reading buffers from connected IIO devices, and sending resutls to standard out.

.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 \-S, \-\-scan
Scan for available IIO contexts, optional arg of specific backend(s) 'ip', 'usb' or 'ip,usb'.
Specific options for USB include Vendor ID, Product ID to limit scanning to specific devices 'usb=0456:b673'.
vid,pid are hexadecimal numbers (no prefix needed), "*" (match any for pid only)
If no argument is given, it checks all that are available.
.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 read, channels must be input.
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 \-i \-c .\fP
.br
\f(CWUsing auto-detected IIO context at URI "usb:3.10.5"\fP
.br
dev 'cf-ad9361-lpc', channel 'voltage0' (input, index: 0, format: le:S12/16>>0)
.br
dev 'cf-ad9361-lpc', channel 'voltage1' (input, index: 1, format: le:S12/16>>0)
.RE
.PP
This captures 1024 samples of I and Q data from the USB attached AD9361, and
stores it (as raw binary) into the file samples.dat
.RS
.B \f(CWiio_readdev \-a \-s 1024 cf-ad9361-lpc voltage0 voltage1 > samples.dat\fP
.RE
.PP
And plots the data with gnuplot.
.RS
.B \f(WCgnuplot \-e \(dq\&set term png; set output 'sample.png'; plot 'sample.dat' binary format='%short%short' using 1 with lines, 'sample.dat' binary format='%short%short' using 2 with lines;\(dq\&\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