Welcome to Flarmradar

While the transmission protocol of the FLARM devices are proprietary (and unusable for our purpose), the ​Data Port Specification is public. The Flarm-Radar project uses the data available on the devices Data Port, just like any 3rd party product.

This wiki should become a source of knowledge for the Flarmradar-Project.

Server

... still needs some writing :-)

Client

The concept of the client software is quite simple. It reads the Data Port from a regular FLARM device (RS232 interface) and streams the data (via the HTTP protocol) to the server which does all computing. Since data streaming does not require much computing power, a mini-computer like the ​Raspberry PI is sufficient. This is a credit-card sized computer that is able to run a Debian-based operating system (Raspbian). The costs for a such a device are negligible (50$ or so).

Infrastructure & Assembly

We used the following components to build up our client infrastructure. Note that links provided are just proposals for your convenience, other components will also work.

• a FLARM device
• a ​Raspberry PI
• Power supply:
  • As Flarm is running on 12V and to ease use of a mobile flarmradar gound station powered by a 12V battery, we recommend a 12V power supply for the flarmradar ground station (FGS)
    • Use a standard power converter (e.g. ​RS-Online) if an electical outlet is available to power the FGS
    • For battery powered FGS, use a 12V battery as used in most gliders
    • To connect the FGS to external power supply or battery, use a connector, which is protected against polarity reversal (e.g. ​RS-Online)
    • To protect your Flarm against over current, a 500mA fuse should be installed in the power supply route to the Flarm (e.g. ​RS-Online)
    • To connect your Flarm to the FGS, we recommend installing a RJ45 connector on the FGS front panel and to use a short network cable to connect the FGS to the Flarm
    • For pin assignment of the RJ45 please consult ​Flarm Installation Manual
    • Wiring instructions: 12V DC In --> Flarm fuse --> RJ45 connector --> network cable --> Flarm
    • Alternative way of Flarm power supply: ​update cable
  • Raspberry is running on a 5V power supply therefore the 12V power supply must be converted to 5V for the Pi.
    • Power conversion can be performed using DC/DC converter. Make sure the DC/DC converter can deliver at least 1A.
    • To protect your Pi against over current, a 500mA fuse should be installed in the power supply route to the Pi (e.g. ​RS-Online)
    • Use a Micro-USB connector to feed the power into your pi
    • Wiring instructions: 12V DC IN --> Pi Fuse --> DC/DC converter --> Micro-USB connector --> Pi
    • Alternative way of Pi power supply: A USB charger to power the Raspberry, just make sure it can deliver at least 1000mA
• Flarm <--> Pi Data connection
  • Flarm delivers RS232 signal on its data port. To feed this signal into the Pi, there are presently two alternatives
  • RS232-USB-cable: Buy a RS232 to USB converter cable. Preferable one which uses the FTDI chipset (e.g TBD). If you use a different chipset, this may not be supported by default by the Pi operating system.

• optional, recommended for a stationary installation: we use currently an ​external antenna

Troubleshooting

• The raspberry-specific issues are collected on a separate page.

Client Software Installation

Download the client and follow the ​installation procedure to install the client software.

The client software is written in ​Perl and should run on any platform where Perl is supported.