Draft-AN-445

Application Note Number

AN-445

Abstract

This Application Note provides a comprehensive guide for building and installing the open-source toolchain for the USRP (UHD and GNU Radio) from source code on a Linux platform. The Ubuntu distribution is specifically discussed.

UHD on Linux

UHD is fully supported on Linux, using the GCC compiler, and should work on most major Linux distributions.

Devices

This document applies only to the USRP X300, X310, B200, B210, B200mini, N200, and N210 devices. The E310 and E312 devices are embedded devices which are fundamentally different from the other non-embedded devices. They are not addressed in this document.

Install Linux

If you already have a recent version of Linux installed, then you may be able to skip this section. If you are starting from scratch, or simply want to start with a new installation of Linux, then please follow the instructions and recommendations in this section.

We suggest that you use either Ubuntu 22.04, Ubuntu 20.04, or Debian Bullseye with a 64-bit architecture. There are several variants of Ubuntu, such as Xubuntu, Lubuntu, Kubuntu, Linux Mint, all of which should work. For the purposes of this document, these variants can be considered equivalent.

Download and install Ubuntu or Debian from the links below. Download the appropriate ISO image, and write it to a USB flash drive. Be sure to verify that the ISO file was not corrupted during the download process by checking the MD5 and/or SHA1 hash.

• Ubuntu download page
• Xubuntu download page
• Debian download page

There are many tools for writing an ISO image to a USB flash drive. On most Ubuntu systems, there is the Startup Disk Creator utility. For other Linux OSs, MacOS, or Windows you can use Balena Etcher, UNetbootin, or many others. See 6 Best Bootable USB Creators for Linux for example.

• Balena Etcher github page
• UNetbootin github page

Be sure to use a USB flash drive with at least 8 GB capacity, and use a USB 3.0 flash drive, not a USB 2.0 flash drive. If you use a slower USB 2.0 flash drive, then the install process will take significantly longer.

Update and Install dependencies

Before building UHD and GNU Radio, you need to make sure that all the dependencies are first installed.

However, before installing any dependencies, you should first make sure that all the packages that are already installed on your system are up-to-date. You can do this from a GUI, or from the command-line, as shown below.

On Ubuntu systems, run:

   sudo apt-get update

On Fedora 21 systems, run:

   sudo yum update

On Fedora 22, 23, 24 and 25 systems, run:

   sudo dnf update

Once the system has been updated, then install the required dependencies for UHD and GNU Radio.

On Ubuntu 20.04 systems, run:

   sudo apt-get -y install autoconf automake build-essential ccache cmake cpufrequtils doxygen ethtool fort77 g++ gir1.2-gtk-3.0 git gobject-introspection gpsd gpsd-clients inetutils-tools libasound2-dev libboost-all-dev libcomedi-dev libcppunit-dev libfftw3-bin libfftw3-dev libfftw3-doc libfontconfig1-dev libgmp-dev libgps-dev libgsl-dev liblog4cpp5-dev libncurses5 libncurses5-dev libpulse-dev libqt5opengl5-dev libqwt-qt5-dev libsdl1.2-dev libtool libudev-dev libusb-1.0-0 libusb-1.0-0-dev libusb-dev libxi-dev libxrender-dev libzmq3-dev libzmq5 ncurses-bin python3-cheetah python3-click python3-click-plugins python3-click-threading python3-dev python3-docutils python3-gi python3-gi-cairo python3-gps python3-lxml python3-mako python3-numpy python3-numpy-dbg python3-opengl python3-pyqt5 python3-requests python3-scipy python3-setuptools python3-six python3-sphinx python3-yaml python3-zmq python3-ruamel.yaml swig wget

On Ubuntu 18.10 systems, run:

   sudo apt-get -y install git swig cmake doxygen build-essential libboost-all-dev libtool libusb-1.0-0 libusb-1.0-0-dev libudev-dev libncurses5-dev libfftw3-bin libfftw3-dev libfftw3-doc libcppunit-1.14-0 libcppunit-dev libcppunit-doc ncurses-bin cpufrequtils python-numpy python-numpy-doc python-numpy-dbg python-scipy python-docutils qt4-bin-dbg qt4-default qt4-doc libqt4-dev libqt4-dev-bin python-qt4 python-qt4-dbg python-qt4-dev python-qt4-doc python-qt4-doc libqwt6abi1 libfftw3-bin libfftw3-dev libfftw3-doc ncurses-bin libncurses5 libncurses5-dev libncurses6-dbg libfontconfig1-dev libxrender-dev libpulse-dev swig g++ automake autoconf libtool python-dev libfftw3-dev libcppunit-dev libboost-all-dev libusb-dev libusb-1.0-0-dev fort77 libsdl1.2-dev python-wxgtk3.0 git libqt4-dev python-numpy ccache python-opengl libgsl-dev python-cheetah python-mako python-lxml doxygen qt4-default qt4-dev-tools libusb-1.0-0-dev libqwtplot3d-qt5-dev pyqt4-dev-tools python-qwt5-qt4 cmake git wget libxi-dev gtk2-engines-pixbuf r-base-dev python-tk liborc-0.4-0 liborc-0.4-dev libasound2-dev python-gtk2 libzmq3-dev libzmq5 python-requests python-sphinx libcomedi-dev python-zmq libqwt-dev libqwt6abi1 python-six libgps-dev libgps23 gpsd gpsd-clients python-gps python-setuptools

On Ubuntu 18.04 systems, run:

   sudo apt-get -y install git swig cmake doxygen build-essential libboost-all-dev libtool libusb-1.0-0 libusb-1.0-0-dev libudev-dev libncurses5-dev libfftw3-bin libfftw3-dev libfftw3-doc libcppunit-1.14-0 libcppunit-dev libcppunit-doc ncurses-bin cpufrequtils python-numpy python-numpy-doc python-numpy-dbg python-scipy python-docutils qt4-bin-dbg qt4-default qt4-doc libqt4-dev libqt4-dev-bin python-qt4 python-qt4-dbg python-qt4-dev python-qt4-doc python-qt4-doc libqwt6abi1 libfftw3-bin libfftw3-dev libfftw3-doc ncurses-bin libncurses5 libncurses5-dev libncurses5-dbg libfontconfig1-dev libxrender-dev libpulse-dev swig g++ automake autoconf libtool python-dev libfftw3-dev libcppunit-dev libboost-all-dev libusb-dev libusb-1.0-0-dev fort77 libsdl1.2-dev python-wxgtk3.0 git libqt4-dev python-numpy ccache python-opengl libgsl-dev python-cheetah python-mako python-lxml doxygen qt4-default qt4-dev-tools libusb-1.0-0-dev libqwtplot3d-qt5-dev pyqt4-dev-tools python-qwt5-qt4 cmake git wget libxi-dev gtk2-engines-pixbuf r-base-dev python-tk liborc-0.4-0 liborc-0.4-dev libasound2-dev python-gtk2 libzmq3-dev libzmq5 python-requests python-sphinx libcomedi-dev python-zmq libqwt-dev libqwt6abi1 python-six libgps-dev libgps23 gpsd gpsd-clients python-gps python-setuptools

On Ubuntu 17.04 systems, run:

   sudo apt-get -y install git swig cmake doxygen build-essential libboost-all-dev libtool libusb-1.0-0 libusb-1.0-0-dev libudev-dev libncurses5-dev libfftw3-bin libfftw3-dev libfftw3-doc libcppunit-1.13-0v5 libcppunit-dev libcppunit-doc ncurses-bin cpufrequtils python-numpy python-numpy-doc python-numpy-dbg python-scipy python-docutils qt4-bin-dbg qt4-default qt4-doc libqt4-dev libqt4-dev-bin python-qt4 python-qt4-dbg python-qt4-dev python-qt4-doc python-qt4-doc libqwt6abi1 libfftw3-bin libfftw3-dev libfftw3-doc ncurses-bin libncurses5 libncurses5-dev libncurses5-dbg libfontconfig1-dev libxrender-dev libpulse-dev swig g++ automake autoconf libtool python-dev libfftw3-dev libcppunit-dev libboost-all-dev libusb-dev libusb-1.0-0-dev fort77 libsdl1.2-dev python-wxgtk3.0 git-core libqt4-dev python-numpy ccache python-opengl libgsl-dev python-cheetah python-mako python-lxml doxygen qt4-default qt4-dev-tools libusb-1.0-0-dev libqwt5-qt4-dev libqwtplot3d-qt4-dev pyqt4-dev-tools python-qwt5-qt4 cmake git-core wget libxi-dev gtk2-engines-pixbuf r-base-dev python-tk liborc-0.4-0 liborc-0.4-dev libasound2-dev python-gtk2 libzmq3-dev libzmq5 python-requests python-sphinx libcomedi-dev python-zmq python-setuptools

On Ubuntu 16.04 systems, run:

   sudo apt-get -y install git swig cmake doxygen build-essential libboost-all-dev libtool libusb-1.0-0 libusb-1.0-0-dev libudev-dev libncurses5-dev libfftw3-bin libfftw3-dev libfftw3-doc libcppunit-1.13-0v5 libcppunit-dev libcppunit-doc ncurses-bin cpufrequtils python-numpy python-numpy-doc python-numpy-dbg python-scipy python-docutils qt4-bin-dbg qt4-default qt4-doc libqt4-dev libqt4-dev-bin python-qt4 python-qt4-dbg python-qt4-dev python-qt4-doc python-qt4-doc libqwt6abi1 libfftw3-bin libfftw3-dev libfftw3-doc ncurses-bin libncurses5 libncurses5-dev libncurses5-dbg libfontconfig1-dev libxrender-dev libpulse-dev swig g++ automake autoconf libtool python-dev libfftw3-dev libcppunit-dev libboost-all-dev libusb-dev libusb-1.0-0-dev fort77 libsdl1.2-dev python-wxgtk3.0 git-core libqt4-dev python-numpy ccache python-opengl libgsl-dev python-cheetah python-mako python-lxml doxygen qt4-default qt4-dev-tools libusb-1.0-0-dev libqwt5-qt4-dev libqwtplot3d-qt4-dev pyqt4-dev-tools python-qwt5-qt4 cmake git-core wget libxi-dev gtk2-engines-pixbuf r-base-dev python-tk liborc-0.4-0 liborc-0.4-dev libasound2-dev python-gtk2 libzmq-dev libzmq1 python-requests python-sphinx libcomedi-dev python-zmq python-setuptools

On Ubuntu 15.04 and 15.10 systems, run:

   sudo apt-get -y install git swig cmake doxygen build-essential libboost-all-dev libtool libusb-1.0-0 libusb-1.0-0-dev libudev-dev libncurses5-dev libfftw3-bin libfftw3-dev libfftw3-doc libcppunit-dev libcppunit-doc ncurses-bin cpufrequtils python-numpy python-numpy-doc python-numpy-dbg python-scipy python-docutils qt4-bin-dbg qt4-default qt4-doc libqt4-dev libqt4-dev-bin python-qt4 python-qt4-dbg python-qt4-dev python-qt4-doc python-qt4-doc libqwt6 libfftw3-bin libfftw3-dev libfftw3-doc ncurses-bin libncurses5 libncurses5-dev  libncurses5-dbg libfontconfig1-dev libxrender-dev libpulse-dev swig g++ automake autoconf libtool python-dev libfftw3-dev libcppunit-1.13-0v5 libboost-all-dev libusb-dev libusb-1.0-0-dev fort77 libsdl1.2-dev python-wxgtk2.8 git-core libqt4-dev python-numpy ccache python-opengl libgsl0-dev python-cheetah python-mako python-lxml doxygen qt4-default qt4-dev-tools libusb-1.0-0-dev libqwt5-qt4-dev libqwtplot3d-qt4-dev pyqt4-dev-tools python-qwt5-qt4 cmake git-core wget libxi-dev gtk2-engines-pixbuf r-base-dev python-tk liborc-0.4-0 liborc-0.4-dev libasound2-dev python-gtk2 libzmq-dev libzmq1 python-requests python-sphinx libcomedi-dev python-zmq python-setuptools

On Ubuntu 14.04 and 14.10 systems, run:

   sudo apt-get -y install git swig cmake doxygen build-essential libboost-all-dev libtool libusb-1.0-0 libusb-1.0-0-dev libudev-dev libncurses5-dev libfftw3-bin libfftw3-dev libfftw3-doc libcppunit-1.13-0 libcppunit-dev libcppunit-doc ncurses-bin cpufrequtils python-numpy python-numpy-doc python-numpy-dbg python-scipy python-docutils qt4-bin-dbg qt4-default qt4-doc libqt4-dev libqt4-dev-bin python-qt4 python-qt4-dbg python-qt4-dev python-qt4-doc python-qt4-doc libfftw3-bin libfftw3-dev libfftw3-doc ncurses-bin libncurses5 libncurses5-dev libncurses5-dbg   libfontconfig1-dev libxrender-dev libpulse-dev swig g++ automake autoconf libtool python-dev libfftw3-dev libcppunit-dev libboost-all-dev libusb-dev libusb-1.0-0-dev fort77 libsdl1.2-dev python-wxgtk2.8 git-core libqt4-dev python-numpy ccache python-opengl libgsl0-dev python-cheetah python-mako python-lxml doxygen qt4-default qt4-dev-tools libusb-1.0-0-dev libqwt5-qt4-dev libqwtplot3d-qt4-dev pyqt4-dev-tools python-qwt5-qt4 cmake git-core wget libxi-dev gtk2-engines-pixbuf r-base-dev python-tk liborc-0.4-0 liborc-0.4-dev libasound2-dev python-gtk2 libzmq1 libzmq-dev python-requests python-sphinx libcomedi-dev python-setuptools

On Fedora 21 systems, run:

   sudo yum -y groupinstall "Engineering and Scientific" "Development Tools" "Software Development Tools" "C Development Tools and Libraries"
   
   sudo yum -y install fftw-devel cppunit-devel wxPython-devel boost-devel alsa-lib-devel numpy gsl-devel python-devel pygsl python-cheetah python-mako python-lxml PyOpenGL qt-devel qt qt4 qt4-devel PyQt4-devel qwt-devel qwtplot3d-qt4-devel libusbx-devel cmake git wget python-docutils cppzmq-devel PyQwt PyQwt-devel qwt-devel gtk2-engines xmlrpc-c-"*" tkinter orc orc-devel python-sphinx SDL-devel swig  zeromq2-devel python-zmq comedilib comedilib-devel thrift-devel python-thrift scipy zeromq zeromq-devel

On Fedora 22, 23, 24 and 25 systems, run:

   sudo dnf -y groupinstall "Engineering and Scientific" "Development Tools" "C Development Tools and Libraries"
       
   sudo dnf -y install fftw-devel cppunit-devel wxPython-devel boost-devel alsa-lib-devel numpy gsl-devel python-devel pygsl python-cheetah python-mako python-lxml PyOpenGL qt-devel PyQt4-devel qwt-devel qwtplot3d-qt4-devel libusbx-devel cmake python-docutils PyQwt PyQwt-devel gtk2-engines xmlrpc-c-"*" tkinter orc-devel python-sphinx SDL-devel swig perl-ZMQ-LibZMQ2 perl-ZMQ-LibZMQ2 zeromq zeromq-devel python-requests gcc-c++ doxygen zeromq-ada-devel cppzmq-devel perl-ZeroMQ amavisd-new-zeromq amavisd-new-snmp-zeromq php-zmq python-zmq czmq uwsgi-logger-zeromq comedilib comedilib-devel pygtk2 ncurses-"*" thrift-devel python-thrift scipy

After installing the dependencies, you should reboot the system.

If the installation of the dependencies completes without any errors, then you can proceed to build and install UHD and GNU Radio.

Building and installing UHD from source code

UHD is open-source, and is hosted on GitHub. You can browse the code online at the link below, which points to version 3.14.0.0, which is the the latest release at the time of this writing.

• UHD repository on GitHub

There are several good reasons to build GNU Radio from source code, especially for doing development and prototyping. It it enables an easy way to customize the location of the installation, and to install multiple UHD versions in parallel, and switch between them. It also provides much more flexibility in upgrading and downgrading versions, and allows the user to modify the code and create customized versions, which could possibly include a patch or other bug-fix.

To build UHD from source code, clone the GitHub repository, check out a branch or tagged release of the repository, and build and install. Please follow the steps below. Make sure that no USRP device is connected to the system at this point.

First, make a folder to hold the repository.

   cd $HOME
   mkdir workarea
   cd workarea

Next, clone the repository and change into the cloned directory.

   git clone https://github.com/EttusResearch/uhd
   cd uhd

Next, checkout the desired UHD version. You can get a full listing of tagged releases by running the command:

   git tag -l

Example truncated output of git tag -l:

$ git tag -l
...
release_003_009_004
release_003_009_005
release_003_010_000_000
...

Note: As of UHD Version 3.10.0.0, the versioning scheme has changed to be a quadruplet format. Each element and version will follow the format of: Major.API.ABI.Patch. Additional details on this versioning change can be found here.

After identifying the version and corresponding release tag you need, check it out:

   # Example: For UHD 3.9.5:
   git checkout release_003_009_005

   # Example: For UHD 3.14.0.0
   git checkout v3.14.0.0

Next, create a build folder within the repository.

   cd host
   mkdir build
   cd build

Next, invoke CMake.

   cmake ..

Note: if the shell PATH is set such that /bin comes before /usr/bin, then this step is likely to fail because cmake will set the FIND_ROOT_PATH to / and this setting will fail as a prefix for Boost headers or libraries. The cmake output will include messages such as

   --   Boost include directories: /include
   --   Boost library directories: /lib/x86_64-linux-gnu

and

   CMake Error in lib/CMakeLists.txt:
     Imported target "Boost::chrono" includes non-existent path
       "/include"
     in its INTERFACE_INCLUDE_DIRECTORIES.  Possible reasons include:
     * The path was deleted, renamed, or moved to another location.
     * An install or uninstall procedure did not complete successfully.
     * The installation package was faulty and references files it does not provide.

One of the following 3 options should fix this situation:

     1. /usr/bin/cmake ..
     2. PATH=/usr/bin:$PATH cmake ..
     3. cmake -DCMAKE_FIND_ROOT_PATH=/usr ..

Once the cmake command succeeds without errors, build UHD.

   make

Next, you can optionally run some basic tests to verify that the build process completed properly.

   make test

Next, install UHD, using the default install prefix, which will install UHD under the /usr/local/lib folder. You need to run this as root due to the permissions on that folder.

   sudo make install

Next, update the system's shared library cache.

   sudo ldconfig

Finally, make sure that the LD_LIBRARY_PATH environment variable is defined and includes the folder under which UHD was installed. Most commonly, you can add the line below to the end of your $HOME/.bashrc file:

   export LD_LIBRARY_PATH=/usr/local/lib

On Fedora 22/23/24/25 you will need to set the LD_LIBRARY_PATH to /usr/local/lib64.

   export LD_LIBRARY_PATH=/usr/local/lib64

If the LD_LIBRARY_PATH environment variable is already defined with other folders in your $HOME/.bashrc file, then add the line below to the end of your $HOME/.bashrc file to preserve the current settings.

   export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

For Fedora 21/22/23/24/25

   export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib64

For this change to take effect, you will need to close the current terminal window, and open a new terminal.

At this point, UHD should be installed and ready to use. You can quickly test this, with no USRP device attached, by running uhd_find_devices. You should see something similar to the following.

linux; GNU C++ version 4.8.4; Boost_105400; UHD_003.010.000.HEAD-0-g6e1ac3fc

No UHD Devices Found

Downloading the UHD FPGA Images

You can now download the UHD FPGA Images for this installation. This can be done by running the command uhd_images_downloader.

   $ sudo uhd_images_downloader

Note: Since this installation is being installed to a system level directory (e.g. /usr/local), the uhd_images_downloader command requires sudo privileges.

Example ouput for UHD 3.13.3.0:

$ sudo uhd_images_downloader 
Images destination:      /usr/local/share/uhd/images
Downloading images from: http://files.ettus.com/binaries/images/uhd-images_003.010.003.000-release.zip
Downloading images to:   /tmp/tmpm46JDg/uhd-images_003.010.003.000-release.zip
57009 kB / 57009 kB (100%)

Images successfully installed to: /usr/local/share/uhd/images

Example output for UHD 3.13:

$ sudo uhd_images_downloader
[INFO] Images destination: /usr/local/share/uhd/images
[INFO] No inventory file found at /usr/local/share/uhd/images/inventory.json. Creating an empty one.
00006 kB / 00006 kB (100%) usrp1_b100_fw_default-g6bea23d.zip
19484 kB / 19484 kB (100%) x3xx_x310_fpga_default-g494ae8bb.zip
02757 kB / 02757 kB (100%) usrp2_n210_fpga_default-g6bea23d.zip
02109 kB / 02109 kB (100%) n230_n230_fpga_default-g494ae8bb.zip
00522 kB / 00522 kB (100%) usrp1_b100_fpga_default-g6bea23d.zip
00474 kB / 00474 kB (100%) b2xx_b200_fpga_default-g494ae8bb.zip
02415 kB / 02415 kB (100%) usrp2_n200_fpga_default-g6bea23d.zip
05920 kB / 05920 kB (100%) e3xx_e320_fpga_default-g494ae8bb.zip
15883 kB / 15883 kB (100%) n3xx_n310_fpga_default-g494ae8bb.zip
00506 kB / 00506 kB (100%) b2xx_b205mini_fpga_default-g494ae8bb.zip
18676 kB / 18676 kB (100%) x3xx_x300_fpga_default-g494ae8bb.zip
00017 kB / 00017 kB (100%) octoclock_octoclock_fw_default-g14000041.zip
04839 kB / 04839 kB (100%) usb_common_windrv_default-g14000041.zip
00007 kB / 00007 kB (100%) usrp2_usrp2_fw_default-g6bea23d.zip
00009 kB / 00009 kB (100%) usrp2_n200_fw_default-g6bea23d.zip
00450 kB / 00450 kB (100%) usrp2_usrp2_fpga_default-g6bea23d.zip
00142 kB / 00142 kB (100%) b2xx_common_fw_default-g3ff4186b.zip
00460 kB / 00460 kB (100%) b2xx_b200mini_fpga_default-g494ae8bb.zip
00319 kB / 00319 kB (100%) usrp1_usrp1_fpga_default-g6bea23d.zip
00009 kB / 00009 kB (100%) usrp2_n210_fw_default-g6bea23d.zip
11537 kB / 11537 kB (100%) n3xx_n300_fpga_default-g494ae8bb.zip
05349 kB / 05349 kB (100%) e3xx_e310_fpga_default-g494ae8bb.zip
00866 kB / 00866 kB (100%) b2xx_b210_fpga_default-g494ae8bb.zip
[INFO] Images download complete.

Building and installing GNU Radio from source code

As with UHD, GNU Radio is open-source and is hosted on GitHub. You can browse the code online at the link below, which points to version v3.7.13.4, which is the the latest release at the time of this writing.

• GNU Radio repository on GitHub

Note: GNU Radio is currently transitioning from major branches of 3.7.x.x to 3.8.x.x. It is generally recommend at this time to use either the v3.7.13.4 or maint-3.7 branch of GNU Radio. The master branch includes many major changes such as converting to use Python 3 and may be unstable.

As with UHD, there are several good reasons to build GNU Radio from source code, especially for doing development and prototyping. It it enables an easy way to customize the location of the installation, and to install multiple GNU Radio versions in parallel, and switch between them. It also provides much more flexibility in upgrading and downgrading versions, and allows the user to modify the code and create customized versions, which could possibly include a patch or other bug-fix.

Similar to the process for UHD, to build GNU Radio from source code, clone the GitHub repository, check out a branch or tagged release of the repository, and build and install. Please follow the steps below. Make sure that no USRP device is connected to the system at this point.

First, make a folder to hold the repository.

   cd $HOME
   cd workarea

Next, clone the repository.

   git clone --recursive https://github.com/gnuradio/gnuradio

Next, go into the repository and check out the desired GNU Radio version.

   cd gnuradio

To checkout the v3.7.13.4 branch:

   git checkout v3.7.13.4

Or to checkout the maint-3.7 branch:

   git checkout maint-3.7

Next, update the submodules:

   git submodule update --init --recursive

Next, create a build folder within the repository, invoke CMake, and build GNU Radio:

   mkdir build
   cd build
   cmake ../
   make

Next, you can optionally run some basic tests to verify that the build process completed properly.

   make test

Next, install GNU Radio, using the default install prefix, which will install GNU Radio under the /usr/local/lib folder. You need to run this as root due to the permissions on that folder.

   sudo make install

Finally, update the system's shared library cache.

   sudo ldconfig

At this point, GNU Radio should be installed and ready to use. You can quickly test this, with no USRP device attached, by running the following quick tests.

   gnuradio-config-info --version
   gnuradio-config-info --prefix
   gnuradio-config-info --enabled-components

There is a simple flowgraph that you can run that does not require any USRP hardware. It's called the dialtone test, and it produces a PSTN dial tone on the computer's speakers. Running it verifies that all the libraries can be found, and that the GNU Radio run-time is working.

   python $HOME/workarea/gnuradio/gr-audio/examples/python/dial_tone.py

You can try launching the GNU Radio Companion (GRC) tool, a visual tool for building and running GNU Radio flowgraphs.

   gnuradio-companion

If "gnuradio-companion" does not start and complains about the PYTHONPATH environment variable, then you may have to set this in your $HOME/.bashrc file, as shown below.

   export PYTHONPATH=/usr/local/lib/python2.7/dist-packages

On Fedora 21/22/23/24, the PYTHONPATH environment variable will need to be set to:

   export PYTHONPATH=/usr/lib/python2.7/site-packages:/usr/local/lib64/python2.7/site-packages/

Configuring USB

On Linux, udev handles USB plug and unplug events. The following commands install a udev rule so that non-root users may access the device. This step is only necessary for devices that use USB to connect to the host computer, such as the B200, B210, and B200mini. This setting should take effect immediately and does not require a reboot or logout/login. Be sure that no USRP device is connected via USB when running these commands.

   cd $HOME/workarea/uhd/host/utils
   sudo cp uhd-usrp.rules /etc/udev/rules.d/
   sudo udevadm control --reload-rules
   sudo udevadm trigger

Configuring Ethernet

For USRP devices that use Ethernet to connect to the host computer, such as the N200, N210, X300, X310, set a static IP address for your system of 192.168.10.1, with a netmask of 255.255.255.0. The default IP address of the USRP is 192.168.10.2, with a netmask of 255.255.255.0. You should probably set the IP address using the graphical Network Manager. If you set the IP address from the command line with ifconfig, Network Manager will probably overwrite these settings.

Connect the USRP

The installation of UHD and GNU Radio should now be complete. At this point, connect the USRP to the host computer.

If the interface is Ethernet, then open a terminal window, and try to ping the USRP with "ping 192.168.10.2". The USRP should respond to the ping requests.

If the interface is USB, then open a terminal window, and run "lsusb". You should see the USRP listed on the USB bus with a VID of 2500 and PID of 0020, 0021, 0022, for B200, B210, B200mini, respectively.

Also try running "uhd_find_devices" and "uhd_usrp_probe".

Thread priority scheduling

When UHD spawns a new thread, it may try to boost the thread's scheduling priority. If setting the new priority fails, the UHD software prints a warning to the console, as shown below. This warning is harmless; it simply means that the thread will retain a normal or default scheduling priority.

UHD Warning:
    Unable to set the thread priority. Performance may be negatively affected.
    Please see the general application notes in the manual for instructions.
    EnvironmentError: OSError: error in pthread_setschedparam

To address this issue, non-privileged (non-root) users need to be given special permission to change the scheduling priority. This can be enabled by creating a group usrp, adding your user to it, and then appending the line @usrp - rtprio 99 to the file /etc/security/limits.conf.

   sudo groupadd usrp
   sudo usermod -aG usrp $USER

Then add the line below to end of the file /etc/security/limits.conf:

   @usrp - rtprio  99

You must log out and log back into the account for the settings to take effect. In most Linux distributions, a list of groups and group members can be found in the /etc/group file.

There is further documentation about this in the User Manual at the link below.

• Threading Notes section of the User Manual