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.TH iio_readdev 1 "29 September 2024" "libiio-0.26" "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.
.TP
.B \-V, \-\-version
Prints the version information for this particular copy of
.I iio_readdev
and the version of the libiio library it is using. This is useful for knowing if the version of the library and
.I iio_readdev
on your system are up to date. This is also useful when reporting bugs.
.TP
.B \-S, \-\-scan [backends]
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.
.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 \-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_readdev -S
.IP serial:[port],[baud],[settings]
which are controlled, and need to match the iiod (or tinyiiod) on the other end of the serial port.
.RS
.IP [port]
is something like '/dev/ttyUSB0' on Linux, and 'COM4' on Windows.
.IP [baud]
is is normally one of 110, 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 38400, 57600, 115200 [default], 128000 or 256000, but can vary system to system.
.IP [settings]
would normally be configured as '8n1' this is controlled by:
.RS
.IP data_bits:
(5, 6, 7, 8 [default], or 9)
.IP parity_bits:
('n' none [default], 'o' odd, 'e' even, 'm' mark, or 's' space)
.IP stop_bits:
(1 [default, or 2)
.IP flow_control:
('0' none [default], 'x' Xon Xoff, 'r' RTSCTS, or 'd' DTRDSR)
.RE
.RE
.IP local:
with no address part.
.RE
.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 should specify a IIO device, and the specific channel to read. Since this is a read, channels must be input.
If no channel is provided, iio_readdev will read from all input channels.
If no device is provided, iio_readdev will print a few examples:
.RS
.B \f(CWiio_readdev -a\fP
.br
Using auto-detected IIO context at URI "usb:3.10.5"
.br
Example : iio_readdev -u usb:3.10.5 -b 256 -s 1024 cf-ad9361-lpc voltage0
.br
Example : iio_readdev -u usb:3.10.5 -b 256 -s 1024 cf-ad9361-lpc voltage1
.br
Example : iio_readdev -u usb:3.10.5 -b 256 -s 1024 cf-ad9361-lpc voltage2
.br
Example : iio_readdev -u usb:3.10.5 -b 256 -s 1024 cf-ad9361-lpc voltage3
.br
Example : iio_readdev -u usb:3.10.5 -b 256 -s 1024 cf-ad9361-lpc
.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