DOKK / manpages / debian 12 / libiio-utils / iio_readdev.1.en
iio_readdev(1) LibIIO Utilities iio_readdev(1)

iio_readdev - read buffers from an IIO device

iio_readdev [ options ] [-n <hostname>] [-t <trigger>] [-T <timeout-ms>] [-b <buffer-size>] [-s <samples>] <iio_device> [<channel> ...]

iio_reg is a utility for reading buffers from connected IIO devices, and sending resutls to standard out.

Tells iio_readdev to display some help, and then quit. -n, --network Use the network backend with the provided hostname
The Uniform Resource Identifier (uri) for connecting to devices, can be one of:
network address, either numeric (192.168.0.1) or network hostname
blank, if compiled with zeroconf support, will find an IIO device on network
normally returned from iio_info -s
with no address part
Use the specified trigger, if needed on the specified channel
Size of the capture buffer. Default is 256.
Number of samples (not bytes) to capture, 0 = infinite. Default is 0.
Buffer timeout in milliseconds. 0 = no timeout. Default is 0.
Scan for available contexts and if only one is available use it.
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.

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

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 iio_attr to find out what the channels are called.

This identifies the device, and channel that can be used.

iio_attr -a -i -c .
Using auto-detected IIO context at URI "usb:3.10.5"
dev 'cf-ad9361-lpc', channel 'voltage0' (input, index: 0, format: le:S12/16>>0)
dev 'cf-ad9361-lpc', channel 'voltage1' (input, index: 1, format: le:S12/16>>0)

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

iio_readdev -a -s 1024 cf-ad9361-lpc voltage0 voltage1 > samples.dat

And plots the data with gnuplot.

gnuplot -e "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;"

iio_attr(1), iio_info(1), iio_readdev(1), iio_reg(1), iio_writedev(1), libiio(3)

libiio home page: https://wiki.analog.com/resources/tools-software/linux-software/libiio

libiio code: https://github.com/analogdevicesinc/libiio

Doxygen for libiio https://analogdevicesinc.github.io/libiio/

All bugs are tracked at: https://github.com/analogdevicesinc/libiio/issues

24 January 2023 libiio-0.24