Building Apps For PlutoSDR Standalone

PlutoSDR includes a single-core ARM® Cortex™-A9 MPCore™ running at 666.66 MHz for which ADI provides a BuildRoot based Linux distribution. This is part of the firmware provided with PlutoSDR. Many users of PlutoSDR run applications on a local PC and stream data to and from PlutoSDR in frameworks like GNU Radio or MATLAB. However, since PlutoSDR is running Linux users can also write C or C++ applications, among others, that can be cross-compiled on a host, and then run on PlutoSDR itself like any other Linux system. This page will discuss an example application, including the necessary tools, to build applications on a host machine and run them directly on the PlutoSDR.

Prerequisites:

  • A host machine to run a compiler on. This can be either Windows (x86) or Linux (x86 or ARM) (yes, you can build PlutoSDR Applications on Raspberry Pi). (it’s possible on macOS, but just more difficult, since you will need to build a toolchain from scratch, beyond the scope of what we’re willing to write - check google, you are on your own).

  • A compiler with the same version used to compile the PlutoSDR firmware. See the Pluto SDR mass storage device file index.html, or check the PlutoSDR firmware releases page for the relevant information.

  • System Root of the firmware used on PlutoSDR itself (this will be downloaded in the example). This includes the libraries (binaries, so you can statically link to things if you want), and headers for those libraries. It’s important that the compiler be told where things are, so it can find the headers and libraries for the Pluto. This can either be done on the command line, or by replacing the default sysroot that the compiler comes with. If you are only compiling things for Pluto - this is a convenient solution, but will eventually will cause problems when you forget, and try to compile something else with this same toolchain.

Once you have the necessary tools we can start to build an application. This example will be done using Linux since it is by far the simplest to set up. We will use v0.30 of the firmware, which is assumed running on the PlutoSDR. If you change the firmware you will likely have to recompile your applications since the compiler or libraries running on the Pluto can change over time.

Set up your Linux Host

  1. Make sure to use either the AMD Xilinx or the Linaro toolchain (you only need one)

    1. Assuming you have the AMD Xilinx SDK installed in /opt/Xilinx, add the necessary tools to your path:

      tcollins@winston: source /opt/Xilinx/Vivado/2018.2/settings64.sh

    2. Grab the Linaro toolchain, unpack it, and add it to the path:

      tcollins@winston: cd /usr/local/bin
tcollins@winston: sudo wget http://releases.linaro.org/components/toolchain/binaries/7.2-2017.11/arm-linux-gnueabihf/gcc-linaro-7.2.1-2017.11-i686_arm-linux-gnueabihf.tar.xz
tcollins@winston: sudo tar -xf gcc-linaro-7.2.1-2017.11-i686_arm-linux-gnueabihf.tar.xz
tcollins@winston: export PATH=$PATH:/usr/local/bin/gcc-linaro-7.2.1-2017.11-i686_arm-linux-gnueabihf/bin

  2. Make sure the compiler is in your path:

    tcollins@winston: arm-linux-gnueabihf-gcc --version

    arm-linux-gnueabihf-gcc (Linaro GCC 7.2-2017.11-rc1) 7.2.1 20171011

    Copyright (C) 2017 Free Software Foundation, Inc.

    This is free software; see the source for copying conditions.  There is NO

    warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

  3. Download the sysroot for your release of firmware, unpack it, and place it somewhere you will find it.

    tcollins@winston: wget https://github.com/analogdevicesinc/plutosdr-fw/releases/download/v0.30/sysroot-v0.30.tar.gz
tcollins@winston: tar zxvf sysroot-v0.30.tar.gz
tcollins@winston: mv staging $HOME/pluto-0.30.sysroot

  4. First create a new directory for this project and move to it.

    tcollins@winston: mkdir /tmp/plutoapp
tcollins@winston: cd /tmp/plutoapp

  5. Grab the example code here:

    tcollins@winston: wget https://raw.githubusercontent.com/analogdevicesinc/libiio/libiio-v0/examples/ad9361-iiostream.c

  6. Cross-compile the example by calling the compiler:

    tcollins@winston: arm-linux-gnueabihf-gcc -mfloat-abi=hard --sysroot=$HOME/pluto-0.30.sysroot -std=gnu99 -g -o pluto_stream ad9361-iiostream.c -lpthread -liio -lm -Wall -Wextra

Using the Linaro Toolchain on ARM hosts

This is a little easier, since the compiler is already for ARM. You can follow the instructions for the i686 devices, but do not install a different compiler. And when compiling, just call gcc:

tcollins@rasberian: gcc -mfloat-abi=hard --sysroot=$HOME/pluto-0.30.sysroot -std=gnu99 -g -o pluto_stream ad9361-iiostream.c -lpthread -liio -lm -Wall -Wextra

Running on Pluto

Copy the executable to PlutoSDR:

tcollins@winston: scp pluto_stream root@192.168.2.1:/tmp/

Run the app:

tcollins@winston:/tmp/plutoapp$ ssh -t root@192.168.2.1 /tmp/pluto_stream

root@192.168.2.1's password: analog

* Acquiring IIO context
* Acquiring AD9361 streaming devices
* Configuring AD9361 for streaming
* Acquiring AD9361 phy channel 0
* Acquiring AD9361 RX lo channel
* Acquiring AD9361 phy channel 0
* Acquiring AD9361 TX lo channel
* Initializing AD9361 IIO streaming channels
* Enabling IIO streaming channels
* Creating non-cyclic IIO buffers with 1 MiS
* Starting IO streaming (press CTRL+C to cancel)

    RX     1.05 MSmp, TX     1.05 MSmp
    RX     2.10 MSmp, TX     2.10 MSmp
    RX     3.15 MSmp, TX     3.15 MSmp
    RX     4.19 MSmp, TX     4.19 MSmp
    RX     5.24 MSmp, TX     5.24 MSmp
    RX     6.29 MSmp, TX     6.29 MSmp
    RX     7.34 MSmp, TX     7.34 MSmp
    RX     8.39 MSmp, TX     8.39 MSmp
    RX     9.44 MSmp, TX     9.44 MSmp

Other standard applications

Depending on the project you are doing - you may need to include something like this in a Makefile project (with the appropriate path changes):

SYSROOT = /home/rgetz/github/pluto/staging/
PKG_CONFIG_PATH=${SYSROOT}/usr/lib/pkgconfig
CC=arm-linux-gnueabihf-gcc
CFLAGS += --sysroot=${SYSROOT}
LIBS += --sysroot=${SYSROOT}