Buildroot-SDR

Buildroot modules used for SDR and ADSB, directed for use on RaspberryPi.

This is an external pack for Buildroot. It is intended to build a base image suitable for NetBooting. My current personal build (to be shared in a different repo later) runs aprox 16M (6.7 after gzip) including:

• busybox
• uclibc
• ntpd
• dropbear
• uchdpc
• nginx (might be replaced later with something smaller?)
• collectd
• strace (for debugging)
• rtl_sdr tools
• fr24feed (Flightradar24)
• bash (for fr24feed, see below)

16248832 May 18 13:49 rootfs.cpio
 6924676 May 18 13:49 rootfs.cpio.gz

Simple start

1. Clone/Install BuildRoot
2. Clone this repository in a seperate directory
3. Add this repo to buildroot by using external customization

Working

dump1090-mutability

This works with RTL devices, and provides json stat files to /usr/share/dump1090 - It also provides a symlink from /usr/share/dump1090 for use with nginx

This is specifically the mutability fork of dump1090

Optionals

• nginx

flightradar24

This will pull ADSB traffic from dump1090 and send to flightradar24 - note, the API key is hard coded and needs to be set.

Dependancies

• bash

Buggies

• Shells out to bash to run ping and hostname, this is stupid and bad. This also means bash is a requirement, and hostname will always fail since busybox hostname isn't the same as regular hostname

Not Working

RRD/Collectd for stats from dump1090

In order to collect stats from dump1090, the dump1090-tools uses python. In order to get these stats into collectd, the python bindings are compiled into collectd. Unfortunatly, this doesn't currently work in Buildroot.

Options

• Make python bindings work in build root -- This isn't trivial. Started down this rabbit hole and found a blocker -- This would require python and it's bindings increasing the size of the image
• Build a pure C plugin for collectd that can be added and compiled -- Non-trivial as it requires C programming -- This is a better option as it wouldn't require python adding to the size of the image

FlightAware / PiAware

PiAware is FlighAwares tools to send data to their systems. It is TCL based and would require TCL interpreter be added to the image. Secondly, they have a tcllauncher project that is used to launch the program. tcllauncher is currently the stumbling block for this project as it did not build cleanly.

Options

• Get tcllauncher building and continue down the rabbit hole -- Unknown requirements to make this work -- This requires the TCL packages be installed, adding to the size of the image
• Build a C or GO option -- This would require reverse engineering how to communicate with FlightAware -- C and GO are both cross-platform, this means a smaller binary would be made instead of interpreted languages

Future

Items to work on for the future include

• Make the build smaller: The goal is netboot, so smaller is better
• Fix the not-working items from above
• Make it easier to config

Configs

The goal here is to have a list of places that might store configs. The question becomes, where and how do you access them.

• SDCard - These go bad, so remote deployments become a pain if they go bad
• Network - This is a good option, but how do you identify where to get the configs -- HTTP -- TFTP